Treatment of periodontitis permanent teeth in children. Choice of treatment. Features endodontic procedures in permanent teeth with immature root.
The most common cause of periodontitis permanent teeth have caries tooth. Microbes, their metabolic products resulting dozapalennya and death of the pulp and, as progression to periodontal tissue inflammation.
Unfortunately, periodontitis often occurs in sealed teeth (despite the treatment of pulpitis).
Periodontitis front teeth of the upper and lower jaws often develops as a result of injury (contusion tooth dislocation, fracture of the root or alveolar ridge).
Very rare, but there may be cases when permanent teeth periodontitis occurs because ortodontychnohovtruchannya therefore premature eruption of teeth and periodontium in the propagation of inflammation and destruction of the tooth is near the fire, etc.
The majority of chronic periodontitis in children develops as a primary hronichniprotsesy , so sign prior pulpitnoy pain is not mandatory. On examination, the tooth may have a significant destruction of the crown , a small cavity, while in the first and in the second case, the teeth can be opened and sealed . Color crowns in most cases modified it a dull, with gray or brown tint , especially in the neck of the tooth. The mucous membrane of the gums are often swollen, pastozna may have Svischevoyi course of purulent discharge or granulation exploding , bone alveolyarnohovid germ – bulges .
The clinical symptoms of gingival margin and alveolar bone are most pronounced when granulating periodontitis and minimally – with fibrous periodontitis.
Diagnosis contributes to the lack of response of dental pulp to thermal stimuli.
To determine the correct treatment strategy and to choose the most efficient method of treatment , diagnosis of periodontitis based on insufficient clinical data , as described symptoms do not allow you to set the state of the root ( the extent of its formation , the presence of pathological resorption, the size and shape of the apical foramen , etc. ), the nature and extent of destructive changes in the periodontium. In this regard, in all cases, the diagnosis of chronic periodontitis permanent tooth x-ray is necessary .
Other forms of periodontitis in children are less common. It should be emphasized that in the age of 9-10 years diagnosed chronic fibrous form of periodontitis is almost impossible because of the wide periodontal space is normal. In the same age game nulematoznyy periodontitis occurs very rarely. These forms are most commonly found after 11-12 years.
Periodontitis
Stages of periodontal treatment
Mechanical preparation, which includes the expansion of the canal and its purification from purulent or serous fluid;
Antiseptic treatment with antibiotics and sulfanilamide preparations. To remove the jaw inflammation inside the tooth root lay antibacterial toothpaste. Modern methods of treatment of periodontitis includes physiotherapy and rinse with warm mineral water. If these methods are not effective, a tooth removed.
Canal filling various modern filling materials. Thanks to modern filling materials and the latest methods of sealing the channels can avoid most complications of caries and periodontal origin . Modern dentistry uses canal filling with natural filling material called gutta-percha .
This material is of two types:
– Flexible percha pins that are used for curved and narrow canals ;
– Termafil – rod with plastic or titanium , which is covered with a layer of gutta-percha .
Manipulations in canal filling performed exclusively under the control renthenoapparatury .
Due to the sealing of the affected channels modern filling materials – gutta-percha, dentists manage optimally fill the micro channel cavity of the tooth , resulting in reduced opportunity periodontal lesions .
Treatment. Defining the indications for use of a method of treatment of periodontitis permanent teeth , it is recommended guided nature periodontitis , the degree distribution of the pathological process in bone and as root, the degree of its formation , the size of the apical foramen, root canal cross-country and others in the multi- teeth issues should be addressed individually regarding not only one tooth, but each one root of the tooth.
Due to the variety of symptoms, the treatment of periodontitis are currently using the following methods: Dial-up single treatment that involves removing decay from root canal , antiseptic and instrumental treatment of them and filling in one visit , sequential processing tool that uses biological antiseptic enzymes and various means of obturation of root canals , the combination of these methods .
Along with these methods, according to individual indications used antibiotics electrophoresis of novocaine , solutions and ointments containing enzymes , antibiotics , corticosteroids, herbs .
Treatment of periodontitis involves permanent teeth effect on com ¬ radicands channel microchannels and periapical inflammation, and in the case of incomplete root formation – the basal cell zone, able to provide closure emerging apical foramen dense tissue ( apexification ) on fibroblasts tsementoblasty , osteoblasts .
Make a quality tool and drug treated ¬ ing root canal with periodontitis in the permanent teeth of children in ¬ needs a precise knowledge of topographic and morphological characteristics of the system ¬ themes root canals of teeth.
Chart. Stages of periodontal treatment:
Choice of treatment of periodontitis permanent teeth in children
Methods of treatment of periodontal permanent teeth in children can be divided into three groups:
1. Conservative methods aimed at preserving the anatomist ¬ chnoyi and functional integrity of the tooth.
2. Conservative and surgical techniques, which include :
– Resection of the root apex – cutting off the tops and remove the affected root adjacent abnormal tissue ;
– Coronal – radicular separation – the lower section mole ¬ ra into two parts in the region of the bifurcation followed by curettage of the area and the tooth covering both segments fused to ¬ Ronco ;
– Root hemisection – removal of the affected root with in ¬ subordinate to him coronal part of the tooth;
– Amputation of the root – the removal of all diseased root to the place of his discharge without removing the crown of the tooth ;
– Replantation of teeth – the placement of the tooth is removed and sealed to the position of the jaw ;
– Kompaktoosteotomiyu followed curettage pryverhivkovyh tissues.
3. Surgical technique – removal of tooth Periodontal infection as a source .
Indications for surgical or conservative surgical techniques is inefficiency or impossibility of conservative treatment or the presence of contraindications to its pro conduct , namely:
– A situation where the tooth is causing acute septic hundred well, chronic infection and intoxication ;
– The complete destruction of the crown if its recovery impossibilitylyve ;
– Extensive root perforation of the wall or floor of the tooth.
The goal of conservative treatment of periodontal permanent tooth is to eliminate pockets of periodontal infection ( the root microflora ¬ Channel ) by careful mechanical and pharmacological treatment of root canal obturation and its creating conditions for regeneration radio ¬ periodontal and periapical bone. During the treatment of periodontitis permanent teeth with incomplete root formation is an important goal of ensuring closure of the apical foramen ( apexification ) to create opportunities for quality obturation of the canal.
The choice of treatment strategy of periodontitis in a child depends on the etiology and course of the process (acute , chronic , worsening of chronic ¬ tion ), the stage of formation of the root , the presence of cell periapical bone resorption , the general condition of the child.
Treatment of chronic periodontitis permanent teeth with incomplete root formation
Treatment of chronic periodontitis permanent teeth with incomplete root formation is of great complexity , even for an experienced doctor and often ends in failure. Root formed has different lengths in different age periods. The walls are parallel root , root canal wide and in the emerging elite overlooks delivery mouth . Periodontal gap is projected only in the region of the root formed along the sidewalls . Compact disc turns over the top , but at the level of the emerging kolbopodibno expanding, limiting sprout area that resembles the appearance of granules ( Fig. 5, 6.14) .
Chart. 5. Central incisor child 7 years
Area growth maintained, wide root canal.
When the root is of normal length , begins forming its apex. There immature stages and uncovered the top. Radiologically the stage immature apex root canal has a smaller width of the neck of the tooth and large in the apex of which is formed , which gives it a funnel-shaped appearance. Periodontal gap is the same width throughout the root and merges at the top of the sprout area. Treatment of chronic periodontitis permanent tooth at the stage of immature apex – a very time consuming process even with knowledge of the anatomical features of the period of the root. In these cases prevalent chronic granulating periodontitis.
Chronic granulating periodontitis develops in immature permanent incisors (usually in the upper jaw ) in children 6 – 8 years as a result of injury and first molars due to acute decompensated current decay. The frequency of each of these reasons is in chronic periodontitis about 30%.
During exacerbation of chronic periodontitis reveal the tooth cavity , gently remove decay from the channel and hold it antiseptic . Tooth leave open the complete elimination of inflammation.
During the treatment of chronic periodontitis permanent teeth with incomplete root formation of a full instrumental ¬ tion and drug treatment in the first visit is often difficult due to ingrowth of granulation tissue into the canal . It must be removed using pulpekstraktoriv under local anesthesia aplika ¬ tion (10% lidocaine ). Leave channel drug antiseptic and anti-inflammatory action . In subsequent visits ¬ tion filled channel drugs on the basis of calcium hydroxide .
In severe cases, prescribe antibiotics and sulfa drugs in doses appropriate age. Recommended drinking liquids , liquid calorie food.
In the etiology and pathogenesis of chronic periodontitis significant role played by the association of different types of microorganisms , as a positive clinical effect can be obtained by applying a set of drugs that act on the aerobic and anaerobic flora . In dental practice for the treatment of root canals using various antiseptics: 0.5-1 % solution of sodium hypochlorite , 3% hydrogen peroxide solution , 0.2 % chlorhexidine , 1% solution hinozola and enzymes.
Great difficulties in the treatment of chronic periodontitis with incomplete root formation also caused some morphological features : low strength walls, small thickness of the root canal , excess mineralized dentin on the root canal walls , hopper extension apical lumen of the root canal , and others. Some pathomorphological features also complicate the treatment of teeth: productive inflammation predominates , there is a great amount of affection because of weak mineralization and bone structure krupnopetlystoyi , granulating tissue tends to grow into the lumen of the root canal with foci of chronic inflammation in the periapical region.
In chronic periodontitis in immature teeth , unfortunately , the zone of growth almost always dies and ceases to root formation.
Method of endodontic treatment in chronic periodontitis teeth with incomplete root formation , aimed at stimulating the formation osteotsementu or similar hard tissue called apexification . The pulp of the tooth that is not viable , sprout area was lost, and the closure of the apical foramen may result in the formation of its lumen mineralizovannoho barrier.
For the treatment of teeth with incomplete root formation using a paste from calcium hydroxide. These medicinal paste is used temporarily. In gangrenous teeth with destructive forms of periodontitis calcium hydroxide change after 5-7 days, 1 month, 3 months, 6 months and 1 year.
X-ray control of apical barrier formation is carried out every 6 months after starting treatment. The final sealing of the root canal constant stopping material is carried out after the completion of the apical stop and completion of the root radiographically detected, the formation mineralizovannoho osteotsementnoho barrier.
Features of the root canals of permanent teeth in children with him Incomplete formation of roots
Given the anatomical and physiological features zubo – jaw apparatus in children and adolescents (wide lumen of the root canal , funnel-shaped extension in the root apex in teeth with immature roots , lack of secondary dentin and stonshenist root at the top ), new technologies endodontic treatment caot be fully transferred to nursery practice.
In permanent teeth with immature roots caot spend quality cleaning and root canal enlargement to form the apical stop, neutralize microflora concentrated solutions of sodium hypochlorite as their use leads to not only dissolve necrotic tissue , as well as the death zone sprout . Nor can obturuvaty quality three-dimensional root canal under pressure using sylleriv and gutta-percha pins due to the anatomical features of the root structure . Therefore, in pediatric endodontic practice in teeth with immature roots applies gentle method aimed at preserving the zone sprout in the living pulp (apeksohenez) and distinguishing infected root canal of periodontal through the creation of a natural (or artificial) mineralized barrier (apexification). Formation of dense natural , mineral barrier is achieved by applying well -known in the dental product – calcium hydroxide , which has unique properties :
bactericidal effect in respect of all types of pathogens due to the high alkalinity of the drug ( pH = 12.4 );
proteolytic action of protein structures relative tissue decay root canal that is virtually indistinguishable from that action of sodium hypochlorite ;
ability of dense mineralized barrier between root canals and periodontal ( granulation with periodontitis)
Algorithm for use of calcium hydroxide to form dense mineralized natural barrier , according A.M.Solovyovoyi , the following :
• diagnosis of the disease ;
• imposition kofferdama ;
• Access to the formation of the root canal;
• working length (in children apekslokatsiyi principle as a way to determine the working length in teeth with immature roots is not applicable );
• gentle cleansing and widening of root canal using neutral chemical substances with antibacterial properties (0.5 % -1% Mr. sodium hypochlorite , 0.05 % chlorhexidine district , yodynol );
• immediately before the introduction of calcium hydroxide root canal need to rinse with distilled water ;
• temporary filling of the root canal calcium hydroxide ;
• imposing a temporary seal.
If living pulp in the root canal calcium hydroxide is replaced every 3-4 weeks. In gangrenous teeth with destructive forms of periodontitis calcium hydroxide change after 5-7 days, 1 month, 3 months, 6 months and 1 year.
The first signs of mineralized apical barrier usually appear after 3 months. It can be seen on radiographs. However, it is still not tight, not fully formed , so it must change the final formation of calcium hydroxide in the root canal after 6 months , 1 year , and even after 1.5 years. The criterion for the formation of dense mineralized apical barrier is light sensing K- file ISO size 30-40 and X-rays.
Multiple entry of calcium hydroxide in the root canal is dictated by the requirements for material apeksohenezu apexification and he must have an active form of pasty consistency, freeze and not easily removed from the root canal. When using calcium hydroxide , depending on the clinical situation in 1-1,5 years formed a dense mineralized apical barrier in 70-100 % of cases ( A.M.Solovyova ).
However , natural apical barrier formed after repeated administration of calcium hydroxide has poroznuyu structure. Therefore, it does not guarantee complete endodontic treatment, and only creates favorable conditions for the completion of treatment endodontychyoho teeth with immature roots. In other words , the formation of apical , barrier using calcium hydroxide are provided for the action , allowing you to further complete the endodontic treatment of restoring the anatomical shape of the tooth.
It is comparatively simple and inexpensive method , but the main drawback of forming mineralized natural barrier between the lumen of the root canal and periodontal treatment is the length and porosity structure formed .
After the formation of mineralized natural barrier is made the traditional root-canal using new technologies ( sealing three-dimensional channel using sylleriv and gutta-percha pins or thermoplastic gutta-percha ). In restoring the shattered crown also applied new technology ( the use of traditional and hybrid cements skloyionomernyh , kompomeriv , chemical and composite curing light and flexible reinforcing structures if indicated ). Metal anchor pins and porcelain crowns to strengthen shattered in pediatric practice are not shown.
To address key deficiencies formation of dense mineralized natural barrier between the root and periodontal using calcium hydroxide (its porosity and duration of treatment ) was offered a new alternative method.
For quick formation of mineralized artificial barrier between root canals and periodontal company Dentsply offered a unique new drug MTA ( Mineral Trioxide Aggregate ) – ProRoot.
Method of application ProRoot for accelerated (artificial) method apexification.
After completion of the chemical and mechanical processing channel in the treatment of destructive forms of periodontitis in the permanent teeth with immature root apex of the root canal 5-7 days injected calcium hydroxide (to achieve sterility of the root canal ). In the second visit to completely remove calcium hydroxide , washed with distilled water and the apical portion of the root canal filled with distilled water mixed with MTA ProRoot. Wait 5-10 minutes. At the same visit after hardening cement fastened root canal using new technology of three-dimensional filling of the channel.
The advantage of using the MTA to create an artificial barrier between mineralized apical root canals and periodontal is to shorten treatment compared with calcium hydroxide. When creating an artificial apical barrier in the treatment of periodontitis due to the high biocompatibility of drug ITA ProRoot almost turns into a dense root structure and tsementoblasty complete the creation of a single set of tissues that performs its function. Application ProRoot also shown at the closing perforations, fractures of the crown and root of the tooth to the root of the extension shattered beneath the gum, followed by restoration of the tooth Thus, the use of calcium hydroxide and MTA ProRoot in endodontic treatment of permanent teeth with immature roots can achieve natural and artificial formation of dense mineralized barrier between the lumen of the root canal and periodontal and endodontic complete treatment using modern technologies used in adults.
Treatment of acute periodontitis permanent teeth in children
Conservative treatment of acute infectious periodontitis aimed at eliminating periodontal inflammation , relieving pain and preventing the spread ¬ inflammation in other parts of the maxillofacial area . The presence of serous or purulent exudate ¬ lyuye brings about the need to create its outflow from periodontal least May ¬ matic way – through the root canal , which is achieved r ¬ leniem necrotic masses of the channel. In the absence of selection eq ¬ sudatu of channel binding is the opening of the apical foramen . Face ¬ ing carried out several visits.
In the first visit should be taken :
– Pain ;
– Opening the cavity of the tooth using a high-speed handpiece ;
– Remove the channel putrydnyh mass submerged antiseptic solution by pulpekstraktora appropriate size , with a very wide channels sometimes have to apply this Me ¬ Meanwhile multiple pulpekstraktoriv ;
– In the absence of fluid outflow through the root canal and SFOR ¬ nating root apex – the opening of the apical foramen for my help file or ¬ rymera ;
– If pid’yasennoho or pidokisnoho abscess – its devel ¬ ting and drainage ;
– Appointment mouthparts baths with 1% sodium carbonate hydro ¬ ;
– Appointment sulfanilamides in case of severe intoxication – antibiotics, analgesic and desensitizing agents in the dosage according to their age ;
Destination of a large amount of liquid without irritating food that does not require heavy chewing , general strengthening therapy.
After the first visit the tooth remains open. A child is prescribed an appointment to come every day , allowing you to control its state ¬ wool , make correction treatment strategy according to the clinical course of the pathological process. Every checked for patency ¬ good drainage periodontal gap and carry antiseptic root canal.
Continued treatment is possible after decrease acute inflammatory ¬ phenomena : spontaneous pain, collateral edema , expressed as ash ¬ Integrity palpation in the region of the patient’s tooth bolisnosti during lane ¬ Kusiy tooth.
At the next visit is conducted:
– Full instrumental and antiseptic root ca ¬ duct using the most effective drugs;
– Input Channel medicinal antiseptic and anti- inflammatory actions in ¬ turundas or as a paste ( Krezofen , Krezodent );
– Insulation cavity of the tooth with a tight bandage temporarily ¬ nd filling material ( dentin – paste , etc.)
For prolonged exudation from the root canal to clean it can be used sorbents with immobilized them likars ¬ Kimi substances or paste from calcium hydroxide .
Last visit is assigned a certain time, which depends ¬ pends on the optimal duration of action of drugs on the root ¬ bundles (usually 1-6 days). In the absence of manifestations su ¬ sharpening process, smooth percussion carry out root canal ¬ it from the described methods (if formed top), X-ray quality control ¬ tion-filled root canal and restore tooth form permanent filling material or continue treatment calcium hydroxide (if not formed top).
Treatment of chronic periodontitis in acute no different from the treatment of acute periodontal infectionstion of origin.
The success of treatment of acute toxic periodontitis ensure rapid evacuation hear ¬ contents of the root canal, the abandonment of the use of potent drugs and the use of antidotes. Reducing exudative phenomena can be achieved by the use of drugs ¬ that work protyeksudatyvnu action (means nitrofuran, hydrocortisone).
In the first visit should be taken :
– Remove devitalizovanoyi pulp;
– Treatment of root canal preparation antidote : when arsenic Periodontitis – 5 % solution unitiola , ¬ thiosulfate to sodium , 5% iodine solution , 1 % solution yodynolu at Jenny tissue damage ¬ periodontal phenol – Castor oil or 10% emulsion in castor anestezina oil;
– Making an antidote to the root canal on turundas ;
– Hermetic closure of the cavity of the tooth for up to 24 hours.
Second visit to appoint the next day. When you gather ¬ tion of pain and bolisnosti percussion repeated handling antidote and restore root bandage another day. The final obturation of the root canal is possible after the disappearance of symptoms of acute periodontitis. Acute toxic periodontitis tooth caot be left open, as this can result in periodontal infection through root canal.
Acute periodontitis caused by combined mechanical and chemical damage output due to periodontal filling material (especially formalinvmisnyh paste ) with apical opening or hematomas associated with the formation of periodontal hysterectomy due to traumatic pulp is treated mainly Physiotherapeutic ¬ cal methods. Assign 5-6 sessions UHF or microwave therapy, pain syndrome – flyukturyzatsiyu momentary electrophoresis with 10 % calcium chloride. Recom ¬ yutsya mouth trays with 0.5-1 % sodium bicarbonate, inside – receiving analgesic drugs. In the case of state ¬ troto purulent periodontal infection due to hematoma sealing mass removed from the channel and the treatment is carried out according to the scheme of treatment of acute periodontal infection origin.
Treatment of chronic periodontitis permanent teeth in children
Treatment of chronic periodontitis permanent tooth with external check ¬ vanym root can be done in one or two visits.
Indications for treatment of periodontitis odnoseansnoho :
– Chronic granulating periodontitis in the presence of fistula on the gums and no relapses and gangrenous decay hnylis ¬ smell it in the channel ;
– Chronic fibrotic periodontitis in the absence of relapse and gangrenous disintegration of putrefactive odor in the channel ;
– Good pass channels;
– Somatically healthy children who are not currently receiving InAmong ¬ well, antibiotics, corticosteroids , or other means of immunosuppressive effect.
On one visit is made complete tool and pharmacological treatment of root canal obturation and its constant root seal with the restoration of coronal permanent filling materials.
With the difficulty of passing root canal treatment , inability to conduct a complete tool and drug treatment channel , reducing the protective functions of organism treatment is carried out in two visits.
In the first visit made:
– Nekrotomiya and forming cavity ;
– Opening cavity of the tooth;
– Remove the channel putrydnyh mass submerged antiseptic solution by pulpekstraktora appropriate size , for a very wide channels sometimes have to use multiple pulpekstraktoriv ;
– Full instrumental and antiseptic root canal by the above methods using the most effective ¬ medicines;
– Filling the root canal treatment or paste contribuSenna turundas a specific remedy ;
– Insulation cavity of the tooth with a tight bandage Volyn NGO temporary filling material ( dentin – paste , etc.).
Permanent obturation channel X-ray control and restoration of anatomic form permanent tooth filling materials perform in the next visit in the absence of complaints and fluid in the channel.
Marginal periodontitis treatment is to eliminate the etiological factor , the use of antiseptic and anti-inflammatory drugs .
In the case of marginal periodontitis infectious origin of the lead ¬ antiseptic agents and broad-spectrum anti-inflammatory therapy. If manure reveal pid’yasennyy abscess stupid by under local anesthesia. Traumatic injury If you want to audit periodontal remove foreign body, if it is detected and implement anti-inflammatory treatment . Poorly imposed seal to be removed . Toxic damage requires the use of appropriate antidotes.
Complications that may occur during treatment of periodontitis permanent teeth in children
|
reason |
Consequences |
Measures to prevent and eliminate complications |
|
Traumatic injury navkoloverhivkovyh tissue |
Exacerbation of inflammation, pain |
Graphed length of root, anti-inflammatory treatment |
|
The use of cytotoxic drugs |
Acute inflammation in the tooth |
Choosing the right medicines |
|
Vidlomlennya endodontic instrument channe |
Failure to seal the root canal |
Wreck removal tool, and if this is not possible, conduct vnutrishnokanalnoho electrophoresis and root-canal |
|
Perforation of the wall of the tooth root |
Acute inflammation, the withdrawal of filling material through the perforated hole |
Trying to pass a root canal and seal the main channel |
|
Excessive vyve-ing filling material at the root apex |
Exacerbation of inflammation, pain |
physical treatment – UHF, UHF-therapy |
|
Incomplete filling of the root canal |
|
Complete sealing of the root canal |
|
The use of non-physicianment effective means for antiseptic against the processing of the root canal |
Acute inflammation after dressing |
Analysis of clinical characteristics and replacement antiseptics |
Feature treating children with symptoms of odontogenic inflammation is that during an acute exacerbation of or when medical intervention is necessary, it should be as complete and painless.
Must all manipulations provodytybezbolisno without applying any forms of violence. This is due to the complex methods of anesthesia and sedatives. For this purpose, the children of primary school age should carry out all manipulation under anesthesia.
Among older patsiyentivzastosovuyut complex sedatives ( andaksyn , tryoksazyn , Seduxen etc.) and efficiently injecting lidocaine anesthesia , Ultrakayin etc.
Getting the treatment of acute exacerbation of chronic periodontitis or temporary tooth in the first visit ( especially if there is an indication for surgery) , you must decide on the feasibility and advisability of saving it temporarily . eshayuschimi thus should not be the child’s age and the timing of eruption of permanent teeth ( “deputy “), and inflammation , the extent and nature of root resorption , the spread of the germ to permanent tooth. It is therefore necessary X-rays .
The success of subsequent treatment of severe acute exacerbation and odontogenic inflammation, prognosis is largely dependent on the reactivity of the child and the effectiveness of selected treatments. In this regard, the attending physician must locate data oon-specific reactivity, which is the configuration parameters and morphology of white blood phagocytic activity of neutrophils, complement titer data electrophoretic study of serum proteins , etc. The shift in the blood picture changes monotsitohramm , phagocytic activity leukocyte activity and complementary serum breach of protective mechanisms in the child’s body , which may largely determine the prognosis.
Treatment of acute exacerbations of chronic periodontitis in children includes:
• Elimination of the reasons that the removal of the pulp , removal of tooth cavity or channel turundas with drugs , removing decay channel, tooth extraction. All this with indications conducted during the first visit.
• Determine the most efficient way outflow of fluid . If the fluid is within the periodontal space should be sent to him through the root canal. If he accumulated under the periosteum and , especially below the gumline , shown cut.
• Definition of rational physiotherapy.
• Assign resources to enhance the resilience of the child :
• antimicrobial treatment;
• hyposensybylyzyruyuschaya and protyvohystamynnaya therapy;
• stimulants .
treatment protocol
Call HIC K Acute apical periodontitis 4.4 permanent tooth
Clinical forms – acute suppurative periodontitis
Diagnostic criteria :
Clinical:
– A sharp pain in the tooth nakushuvanni ;
– Constant throbbing , growing pain in a tooth ;
– Feeling “grown tooth ” ( it is higher than the adjacent teeth ) and the first to come into contact with the antagonists
– Facial asymmetry due to swelling of soft tissue on the affected side ;
– Fever, lethargy , poor sleep
can raise the temperature to 38- 390S .
– The affected tooth may be intact , sealed or can be deep carious cavity which communicates with the cavity of the tooth;
– Sensing walls, floor cavity , place a combination of oral and mouth tooth root canal painless ;
– No response to thermal stimuli ;
– Painful response to percussion of the tooth ( vertical and horizontal ) , abnormal tooth mobility
– The mucous membrane of the gums and transitional folds in the area of the affected tooth apex , edematous , hyperemic, smoothed , painful on palpation ;
– Regional lymph nodes on the affected side are enlarged and painful on palpation ;
Ancillary diagnostic criteria
– Reduced (100 mA) or no response to an electric current at elektroodontodiahnostytsi ;
– No change in bone peri apical area with X-ray studies .
Treatment:
Conservative treatment is carried out in the absence of :
– Situations where tooth is causing acute septic condition, chronic infection and intoxication ;
– The complete destruction of the crown ;
– Perforation of the floor of the tooth;
Local treatment :
And visit the patient
– Antiseptic mouth ( rinse)
– Anesthesia : anesthetics (local ), with abrupt bolisnosti – conduction anesthesia
– Preparing a tooth cavity , taking into account topographic anatomical features of the affected tooth
– Opening the cavity of the tooth (using high turbine handpiece ) and root canals for the outflow of fluid
– Instrumental treatment of the root canal ( channel ) on the full working length using appropriate size endodontic instruments
– Opening of the apical foramen
– Drug treatment of root canal antiseptic preparations;
– Closing the cavity loose bandage ( cotton balls )
– Appointment of frequent rinsing of the mouth and staggered tooth antiseptic solutions
Second visit to the patient
– Antiseptic mouth ( gargle antiseptic )
– In the absence of pain: an instrumental treatment of the root canal ( channel ) on the full working length using appropriate size endodontic instruments
– Opening of the apical foramen
– Drug treatment of root canal antiseptic and anti-inflammatory drugs . Apply no irritant periodontium and speed of drugs : antiseptic solutions : halogens and oxidants (1% chlorhexidine district , 1% Mr. yodynolu 3% Mr. hydrogen peroxide , etc.) Quaternary ammonium compounds (0.5 % -1 etoniyu % solution , 1 % solution of benzalkonium chloride 0.15 % solution decametoxine ), phenolic compounds (5% phenol solution , 1% solution of camphor – paramonohlorfenolu and complex preparations ), nitrofurans , antibiotics , drugs and immobilized sorbents, anti-inflammatory drugs, etc.
– In the left channel turundas abundantly moistened selected medicinal drugs
– Closing the cavity or semi-hermetic airtight bandage (depending on whether or not a small amount of serous fluid in the channel )
Third patient visits
– Antiseptic mouth ( gargle antiseptic )
– In the absence of pain – removing the sealed ( semi-hermetic ) dressing
– Sealing of the root canal ( channel ) within the root apex hole materials for root fillings;
– Filling the cavity , and if necessary restore the crown cement, kompomeramy , composite, silver amalgam , etc. , depending on the topographic anatomical features of the affected tooth. Possible delayed filling , then close the carious cavity temporary seal with temporary filling material.
General treatment :
– Depending on the general condition of the patient is prescribed analgesics, antibacterial and hyposensitization preparations
Recommendations patients:
– For rational oral hygiene and tooth brushing technique
– By application of personal hygiene products ( toothbrushes medium hard flosses );
– By application of health care toothpastes containing fluoride , calcium and minerals
Prevention of relapse :
– Clinical supervision of a dentist ( at least once a year) in the case of decompensated current decay – often
Possible results :
1 .) If the effectiveness of the treatment – no complaints of pain in the tooth nakushuvanni painless response to percussion , the absence of pathological changes in the mucosa of the projection of the roots of the affected teeth , X-ray – filling in weight throughout the root canal , no pathological changes in the periodontium.
2). In case of failure of the treatment – of secondary caries progression of inflammation in periodontal and transition to chronic , worsening of the pathological process in periodontal origin of odontogenic inflammatory processes of the maxillofacial area ( abscess , abscess , etc.)
Performance measures of treatment:
The stabilization process: complete absence of pathological changes in periodontal saving seals for a long time , recovery of form, function and cosmetic qualities of tooth.
treatment protocol
Call HIC K 5.4 Chronic periodontitis permanent tooth
Clinical forms – chronic periodontitis, the period of acute
Diagnostic criteria :
Clinical:
– Constantly growing pain in a tooth ;
– A sharp pain in the tooth nakushuvanni ;
– Baby fever , lethargy , poor sleep ;
– Facial asymmetry due to swelling of soft tissue on the affected side ;
– Deep carious cavity in the tooth , which communicates with the cavity of the tooth;
– Probing the walls, floor and cavity space communication with the cavity of the tooth and is a painless root canal ;
– No reaction when exposed to thermal stimuli ;
– Sharply painful response to percussion of the tooth, tooth mobility
– The mucous membrane of the gums and transitional folds on the affected tooth hyperemic , edematous, sharply painful on palpation ;
– Regional lymph nodes on the affected side are enlarged and painful on palpation ;
Ancillary diagnostic criteria
– Reduced (100 mA) or no response to an electric current at elektroodontodiahnostytsi formed by the roots ;
– Thinning of bone tissue without clear boundaries at the top and root bifurcation at X-ray ( granulating periodontitis) , or the presence of limited dilution of bone at the root apex ( granulomatous periodontitis) .
Treatment:
Conservative treatment is carried out in the absence of :
– Situations where tooth is causing acute septic condition, chronic infection and intoxication ;
– The complete destruction of the crown without the possibility of recovery;
– Perforation of the floor of the tooth;
Treatment of exacerbations of chronic periodontitis in the permanent teeth of the formation of roots :
– Anesthetics ( local)
– Opening the cavity of the tooth using a high-speed handpiece for root canal and outflow of purulent exudate
– Instrumental treatment of the root canal ( channel ) on the full working length using endodontic files of appropriate size
– Drug treatment of root canal antiseptic preparations;
– Temporary obstruction of the channel ( channels) nepodraznyuyuchoyu paste or preparation for turundas that has a strong antimicrobial and anti-inflammatory effects ;
– Closing the cavity in a tooth with a temporary bandage filling material
– Sealing of the root canal ( channel ) within the root apex hole materials for root fillings;
– Restoration of tooth dental cements kompomernymy or composite materials , silver amalgam
Treatment of exacerbations of chronic periodontitis in the permanent teeth with immature root:
– Preparation of the cavity , opening the tooth cavity using a high-speed handpiece and creating access to the root canal
– Instrumental treatment of the root canal ( channel ) on the full working length using endodontic files of appropriate size
– Drug treatment of root canal antiseptic preparations;
– Temporary obstruction of the channel ( channels) paste based on calcium hydroxide , closing the cavity in a tooth with a temporary filling material
– Temporary root canal filling paste based on calcium hydroxide , clinical examination within 3 years – the closure of the apical foramen ;
– Sealing of the root canal ( channel ) within the root apex hole materials for root fillings after the formation of the apical foramen ;
– Restoration of tooth dental cements kompomernymy or composite materials , silver amalgam
Clinical examination within 3 years – the closure of the apical foramen :
General treatment
– Antibiotics – in the case of severe intoxication
– Painkillers
– Recommendations food ( plenty of fluids nepodraznyuyucha food).
Performance measures of treatment:
– The elimination of the clinical manifestations of the disease ;
– Restoration of the anatomical shape of the tooth.
Treatment phased in dentist ends sealing the tooth and its root. First, to eliminate the need to surgically inflammation wide departure date effusion ( serous or purulent ). Appointed physiotherapy , warm rinse warm mineral water, sulfa drugs , broad-spectrum antibiotics . When treatment failure , and if the tooth does not stand the tightness , it is subject to removal.
Treatment of chronic periodontitis involves three main stages:
• mechanical preparation ( expansion clearance)
• antiseptic treatment ( disinfection )
• canal filling
Machining is carried out to the complete removal of the root pulp and infected dentin layer of the walls of the channel. Disinfection channel often complete application vnutrikanalnoho physiotherapy ultrasound exposure.
Then carry out the procedure by reducing inflammation in the jaw and stimulating reparative processes in bone. At the root of the tooth buried absorbable anti-inflammatory and anti-bacterial toothpaste . zZastosovuyut physiotherapy .
After the relief of inflammation in periodontal channels carefully fastened . In 85 % of the combined treatment of periodontitis is effective and recovery occurs .
If you spent a combined therapeutic intervention caot eliminate granulomas resort to ektomiyi apex of the tooth root , followed by fixation of the tooth in the jaw alveoli. Sometimes all activities undertaken unsuccessful , in which case the affected tooth must be removed . After the relief of inflammation in bone decide on the prosthesis or implant tooth.
Treatment of acute and chronic periodontitis
Periodontal disease is common , being one of the more common causes of inflammatory diseases of the maxillofacial area and udaleniya teeth. Being a chronic inflammatory odontogenic fireplace, periodontitis is a source of sensitization of the patient , leading to significantly change the immune status , reducing nonspecific rezistentnosti , development and complications of various somatic diseases. Effectiveness of conservative treatment of periodontitis on average 85%, and that the figure varies depending on the clinical form of the disease , means and methods of treatment, the resistance of the patient and many other factors. Difficulty of treating periodontitis caused lasting regeneration processes Ochag destruction periapikalnoy area that is mostly observed in 6 – 12mes . or more after completion of endodontic treatment. Another problem zatrudnyayuschey or even exclude the possibility of direct endodontic treatment of exposure to periodontal feature is the anatomical structure of the root canals of teeth.
One of the most important causes of the possible complications of the treatment of periodontitis may serve as the severity of the mechanisms of nonspecific resistance of the organism and the activity of tissue regeneration processes . Due to this promising use of drugs and physical therapy factors okazyvayuschih immune- stimulating effect, correcting immune status, aktiviziruyuschih sanogenesis mechanisms and physiological processes of reparation.
The purpose of the treatment of periodontitis – the elimination of inflammation in periapikalnoy area, isklyuchenie pathogenic effects on the body odontogenic inflammatory foci , regeneration of periodontal tissue structure and function of the tooth restoration .
Endodonticheskoe treatment involves three main stages: mechanical preparation ( enlargement treatment) , antiseptic treatment ( disinfection) and sealing channels.
Mehanicheskaya processing is carried out to the complete removal of disintegrated pulp and root dentin layer infected with the channel walls . For successful implementation etogo stage must create a full access to the root canals with the calculation to the longitudinal axis of the working part of endodontic instrument maksimalno coincides with the direction of the move canal. Delete the contents of the channel sleduet phases, fractional portions , from the mouth of the channel under prikrytiem antiseptic solutions , constantly replacing it with fresh portions.
You can use 3% solution of hydrogen peroxide, Furacilinum 1: 5000 , 0,5 – I% solution of chlorine bleach , 0.02% chlorhexidine , 1% solution yodinola 1% solution yodopirona 40 % solution of dimethyl sulfoxide , 1% alcohol rastvor chlorophyllipt 0.01 % solution mefenaminata sodium salt , 0.5 % solution ekteritsida 1 – 3% solution metakrezolsulfonovoy acid ( gravity ) and other antiseptiki .
For antiseptic treatment of feed with periodontitis can be applied sleduyuschie drugs : Endoperox as a solution , Endotine, Rarsan (3 % solution of sodium hipohlorita firm Septodont), Histolith solution of sodium hypochlorite (LegeArtis).
To facilitate the machining of root canal helatiruyuschie widely used drugs can cause rapid local demineralization dentina kanalu.Demineralizovanoyi root dentin walls while significantly razmyahchaetsya and easily removed instrumentally. Drugs in this group include etilendiamintetrauksusnuyu acid ( EDTA ). Famous domestic product – Trilon- B, as well as imported – Largal Ultra ( company Septodont) as a solution , ‘Canalt’- Gel suitable for use , Calcinase (LegeArtis) as a solution . NEti drugs have also disinfectant action.
Drugs administered in feed no more than 5 minutes. Then , following mehanicheskuyu treatment should be abundantly rinsed with distilled water channels or saline to neutralize the environment , or ongoing violations will result in demineralization adhesion and inability hermetichnoy canal obturation with further sealing.
Mehanicheskuyu root canal treatment should begin with the extension uhlubleniya and forming the mouth of the channel with small diameter spherical hog ( bend the tip have to use extra long burs –
Prix the best match to the longitudinal axis of the tool used endodontic root canal and directions decreases the possibility of creating nerovnostey (‘ steps ‘) on the walls of the channel , which complicates its processing. The working part of the tool in this position more fully rooted facing walls of the channel across the length and tool efficiently performs its functions.
For the treatment of root canals using drilbory , drills , reamers and rasps kornevye different standard diameters and lengths. Endodontic instruments mogut have a length of
Poocheredno using different types of endodontic instruments, consistently increasing the diameter of the smallest rooms – 0.6 , 0.8 , and 10 for a possible large-diameter channels provide the desired shape and a smooth clean Surface , provides input filling material and its adhesion. NVse processing steps instrumental duty of medication exposure antiseptikom .
Disinfection channel effectively terminate use of ultrasound vnutrikanalno using endodontic needle waveguide radiator , Introduction to channel through the solution antyseptyka.Aktyvne injection solution in mikrokanaltsy dentin at the expense of its vibration and cavitation. NNahrevanie also increases the disinfectant ability rozchynu.Instrumentalna Processing canal apical end with otverstiya physiological and anatomical opening of the apical foramen of the tooth root .
Follows the stage of endodontic treatment – influence aimed at eliminating inflammation in periodontal tissues and stimulation of regenerative processes. NFor this purpose, medications and physiotherapy factors alone, together or in combination .
Proteoliticheskie enzymes provide nekroliticheskoe and mucolytic action facilitates the evacuation of content channels , increase the effectiveness of antimicrobial action of preparativ.Rozchyny trypsin, chymotrypsin, himopsin, terrilitina possess bacteriostatic action and help neutralize bacterial toxins. Prepare medications ex tempore, dissolving enzyme powder in isotonic or oil solution of vitamin E and other good effect daet enzyme lysozyme in a 1% isotonic . Lysozyme is a factor in the natural resistance of body tissues, improves fahotsitarnoy activity of leukocytes , which is beneficial to the current periodontitis . For prolonged enzyme preparations made profezim and immozimaza – enzymes immobilized on an organic matrix.
Treatment of acute periodontitis
Acute drug-induced periodontitis resulting from the toxic action of certain drugs (most often – arsenic .) First stage – intoxication . Toxic drugs irritate the periodontal tissue , which is accompanied by tenderness to nakusyvanii on zub.Spetsyfichni antidotes vstupayut reaction with toxins found in the blood and tissues and form a connection with them netoksichnye and removed .
Browser stage of intoxication , when the symptoms of acute inflammation of the periodontal no signs of severe exudation during anesthesia reveal the tooth cavity , prepared endodonticheskiy access and carry out machining channels. Expand Land physiological narrowing in the apical part of the channel and reveal verhushechnoe small diameter hole drilbora ( without the extension). Spend antisepticheskuyu processing and channel leave turundas one of the used drugs during temporary airtight bandage daily. Over a one day drugs in the channel leaving pointless, because by the time they lose UTB activity in specific environmental conditions of the root canal .
Hvozdichnoe most long oil retains the antiseptic qualities , but when it is used to consider the possibility of irritating effects on periodontal tissues . In this case, the channel can be filled daily pasta Fokalmin ( firm LegeArtis) and tooth cavity is closed temporary seal. Also effective drugs for the treatment of canals and Rarsan Endotine ( company Septodont).
Endodonticheskoe medication is held against the backdrop of laser or magnetic therapy on the first visit. When using IHNL set sleduyuschie parameters: capacity 150-170 mW/cm2 , exposure 2 min. was 3 sessions. Measurements of magnetic therapy: frequency 100 Hz modulation frequency of 0.8 Hz, the duration of one session to 20 minutes. , On treatment of 15 sessions , ezhednevno . On the next visit , repeat drug treatment channel and clinical well-being Prix – fastened to the level of the apical foramen roots. Root Canal Treatment alcohol, ether and air dried before plombirovaniem less effective compared to the effect of the drug Fokaldre (LegeArtis), rastvor which disinfects , cleans and dries very quickly channel. For plombirovaniya can use domestic materials: phosphate cement intradont , Biodent and import : ‘Cariosan’ ( Slovakia ), ‘Hermetic’ (LegeArtis), ‘Endomethasone’, ‘Endobtur’ (Septodont). Treatment of acute periodontal infection in stage exudation
Age of intoxication quickly turns into exudative , accompanied narastayuschim edema, accumulation of inflammatory exudate in periapikalnoy area and increased pain. This should provide a flow of fluid from periodontal . Under anesthesia reveal the tooth cavity and produce mechanical obrabotku channels combined with an active drug disinfection.
Anatomicheskoe hole apical root canal tooth reveal and expand to create a flow of inflammatory exudate and gain Medicamentous effects on periodontal tissues . With insufficient outflow through the channel at this stage of periodontitis for proper drainage of periodontal indications to produce periostotomiyu . Patients prescribed overall treatment: broad-spectrum antibiotics , sulfa drugs and desensitizing . The tooth is left open to the termination abundant exudation from the channel. NPri Recommend this patient mouth with antiseptic baths and soda rastvorami and possibly often be repeated drug obrabotku endodontic .
The browser shows this situation, especially the use of proteolytic enzymes in combination with antiseptics. Effective treatment of glucocorticoid channel and use them as applications for transitional fold in the causal tooth. Local ( endodontic ) use of antibiotics in the treatment of periodontitis are currently not widely used in ambulatory practice stomatolohicheskoy allergization due to significant population and complexity soblyudeniya principles of rational antibiotic therapy for local single double use of the drug. Continue treatment after the outflow of fluid carefully obrabatyvaya channels antiseptics.
It is known that when periodontal root canal is a mixed microflora, including anaerobic . Signs of anaerobic infections – dark color soderzhimoe root canals with putrid odor. Thus traditionally in the treatment of periodontitis ispolzuemye antiseptics are ineffective. For endodonticheskoy drug treatment should be used nitrofuranovye drugs dioxidin 1-0,5 % solution , suspension baktrima , as well as metronidazole and fuzidinnatriy (preferably inside).
Can be used for putting pasta in root canals – Grinazole, soderzhaschaya metronidazole and Septomixine forte – endodontic paste deksametazonom.Plombuvaty channels in the most appropriate root filling materials Endomethazone containing corticosteroids and metronidazole (Septodont).
As mentioned above, used laser and magnetic therapy . Parameters used IHNL Colour 180 – 200 mW/cm2 irradiated with 2 fields for 2 minutes . 2-3 sessions, schodnya.Parametry magnetic therapy : frequency 100 Hz modulation frequency 0, 8 Hz , the magnetic induction of 12 mT , exposure time 15 min . , A course of treatment is 10-15 procedures performed daily.
For the prevention of relapse after root canal can be done in’ektsiyu 0.2-0.5 ml emulsion of hydrocortisone in transition crease in lechennoho tooth.
Treatment of chronic periodontitis
Treatment of chronic periodontitis aimed at eliminating inflammation periodonte and creating conditions for the regeneration of the periapical tissues. Features of treatment of chronic periodontitis fibrous . In the first visit , after completion of the mechanical training channel and medicinal , antiseptic Processing , anatomical root apical hole open, but tselenapravlenno not expand. In the left channel turundas with antiseptic solution pod sealed in a temporary bandage tooth cavity . On the next visit , when clinically well-being, after repeated drug treatment plombiruyut channel . To enhance recovery of periodontal structures effectively primenenie IHNL and MT.
Prix laser in this case, a smaller capacity – 60-80 mW/cm2, but a larger number of radiation fields -4-6. Exposure – 2 min. for each field. NParametry magnetic therapy: frequency 50 – 60 Hz frequency modulation tion 0.6 Hz nappyazhennoct electromagnetic field – 8 – 10 mT, exposure time 10 min., On treatment of 10 sessions, one day.
Treatment of chronic granulomatous granulating periodontitis.
These clinical forms of periodontitis are characterized by the vyrazhennymi destructive periodontal changes , the growth of granulation tissue in okoloverhushechnyh foci of chronic inflammation. When machining channel produces gentle opening and expansion of the anatomical apex otverstiya root.
In the treatment of granulating and granulomatous periodontitis shown zaapikalnaya therapy – an introduction to periapikalnye fabric of drugs stimuliruyuschih regeneration of periodontal pockets of destruction . Pre spend tschatelnuyu antiseptic channel , which eliminates withdrawal by , the boundaries Root infected with content and microbial drugs. NLekarstvennye drugs as a solution or paste is injected into the apical portion Root turundas or kanalonapolnitelem . Can be used lizotsima 0.1 % solution for flushing channel and lysozyme -vitamin paste – for zaverhushechnoho vyvedeniya . Pasta contains lysozyme, an oil solution of vitamin A ( or E) and napolnitel.
Browser its composition may include calcitonin. In zaverhushechnoy therapy can be used such biologically active substances as honsurid , Methyluracilum, Heparin mixed with furazolidone and dimethyl sulfoxide , prepared as a paste . Effectively use embrioplasta ( allogeneic embryonic tissue of early development), which stimulates the reparative osteogenesis in Ochag destruction.
Given the resistance of the organism inhibiting factor in chronic inflammatory processes in periodontal should be used for output zaapikalnoho imunomodulyatory.Naybilsh often use levamisole (dekaris ) in the paste . Successfully used a combination thymogen, levamisole and hidrokortizona . Use pentoksil both locally and for general treatment. While assuring normal immune status improves regeneration in early period and in bolshej degrees positive dynamics klinikorenthenolohicheskih indicators , increased the percentage of favorable outcomes.
Izuchena efficiency of the plant for the purpose of preparation of multifunctional action erakonda , 10 to 40% aqueous solution which nativnyy or drug was administered periapikalnye cloth and leave in a channel per day. The product is non-toxic and has immunomodulatory effect and stimulates physiological processes of tissue repair , thus providing a good therapeutic effect in the treatment of periodontitis.
Widely used osteotropic calcium pastes zaverhushechnoho vyvedeniya . Good results are obtained by delayed filling of channels predpolahayuschee zaverhushechnoe output osteoinduktivnyh pastes and calcium channel vremennoe stopping for a few months (usually 3 – 6 months.) . In terms ukazannye observe the dynamics of the source of destruction in periodontal dental radiography osnovanii data and clinical and instrumental examination . NPri starting regeneration of periodontal root canal is sealed indifferentnym permanent filling materials. Often channel tverdeyuschim material fastened to the level of the apical foramen immediately after withdrawal of therapy zaverhushechnoho paste.
Prix chronic granulating periodontitis can be used in almost all known physical therapy techniques. This can be yodosoderzhaschih electrophoresis substances enzyme solution , phonophoresis, mahnitoforez , UHF , microwave – therapy , laser and magnetic therapy . IHNL Options : Power 90-100 mW/cm2 4-6 radiation fields in the mucosa of the causal tooth when exposed to techenie 2 min. for each field . Parameters MT NISMEMP : frequency 70 – 80 Hz, 0.6 Hz modulation , voltage of 10 mT , time – 15 min. , 10 sessions.
Conclusions
In the treatment of periodontitis should use the full range of available funds lechebnogo – medication and physical therapy . The most effective laser ( IHNL ) and magnetic ( NISMEMP ). Results of treatment of periodontitis determines the complete obturation of the root canal and the level of nonspecific rezistentnosti the patient. Clinical forms of periodontitis are less impact on treatment outcome. The question of the need for radical treatment focus periapikalnoy destruction (use one of the methods odontoplastiki or tooth extraction) should be resolved within 6 – 8 months. Dynamic observation of the periodontal tissues , according to X-rays, high-quality after root-canal.
canal treatment
- MAIN aim of endodontic Treatment javljaetsja vosstanovlenye function, characteristic for the main goal of endodontic treatment is to restore function, character-tion for healthy teeth. It is conducted in acute and chronic pulpitis and all forms of periodontitis. Endodontic treatment – this is, in fact, root canal treatment in the area of the pulp.
- It consists of:
- • access to the channel;
- • removing content from the channel;
- • canal filling material that promotes sealing.
The main stages of endodontic treatment
During root canal treatment necessary follow-up procedures.
After the procedure, anesthesia, dentist isolates the tooth from saliva around the teeth by putting a thin sheet of rubber, which is called koferdamom dentistry . This thin sheet of rubber is held in the mouth a little clip, Attach attitude to tooth. This complete isolation of the tooth from saliva is needed in order to prevent the ingress of bacteria from saliva in the root canal during a very important procedure – clean feed.
Access to the channel is ensured proper cavity preparation , removing the pulp chamber roof , creating easy access to channels for endodontic instruments.
Cleaning the root canal involves mechanical and chemical disinfection. At the stage of cleaning the root canal is the removal of important bacteria, the pulp tissue, which can be nekratizirovana and infected.
File processing is carried out along the entire length of the root canal up to the top of the root , but not beyond.
It is therefore necessary to determine the length of the root canal . To do this , the dentist inserts the first channel files and X-ray , and determined by which etsya – length of root canals.
The Chemical disinfection carried dentist is th irrigation canals special disposable needles.
After thorough cleaning of the root canal , the dentist starts canal filling .
Filling of the channel – the final stage of treatment. The success of the root canal is largely determined by the quality of performance of previous endodontic procedures.
The basic requirement of this stage is a reliability -ness sealing root canals. Prior to seal -tion canals dried with paper pins.
For filling root canals using gutta-percha and paste. Percha – a rubber material that is made in the form of cones. The size and shape of the gutta-percha the form and size of the files , in which clean out the root canals . Gutta-percha cones covered with paste and put into the root canals of the tooth. For good sealing of the root canals introduced several cones.
Huttaperchevyy pin and special paste
After the root canal, the dentist places a temporary seal. The channel must be sealed to the top without voids and defects.
After that appointed the next visit, during which the dentist puts a permanent seal.
Restoration of teeth after endodontic treatment
Upon completion of root canal treatment, the dentist decides restore the tooth. Restoration of teeth after endodontic therapy is performed in several ways: filling composite materials ( that match the tooth color ) fillings with composite materials by means of pins , use of crowns.
The fact is that in many cases during endodontic therapy tooth loses quite significant amounts of dental tissues. This is due to large old fillings, because of the large cavities or breakage of the crowns , etc. The teeth in this state are fragile, and the dentist to decide the issue of adequate restoration of teeth.
The question of the restoration of teeth that have lost a significant amount of hard tissue , is solved by means of root pins.
Root pins
Root pins ( in dentistry are known as anchor pins ) – a rod , usually made of metal , which are set and fixed at the root of the tooth.
To install the pins dentist removes a bit of gutta-percha (which was filled root canal ) for space facilities pin. Then pin is fixed with cement in the root canal , and then on top of it overlaps the filling material to restore the anatomical shape of the tooth. Thus, the use of pins strengthens tooth devoid of large amounts of hard tissue . Sometimes there are situations in which the pin and the sealing material caot achieve adequate strength. In such cases , to achieve a good strength to put on artificial tooth crown.
Root canal curvature
Most root canals are curved instead of straight. In addi- tion, curved root canals are relatively narrow when c ompared to their straight counterparts. Root canals typi- cally accelerate in curvature and exhibit their greatest anatomical complexity towards their apical terminus. Root canal curvature can be described by level (coronal, middle or apical), angle and radius. Most curvatures are multiplanar and are thus expressed in both the mesiodistal and buccolingual (or buccopalatal) plane. The fact that root canals are curved and narrow in mature teeth makes it difficult to clean them of tissue and infectious elements as well as to shape. The risk of canal straightening and the creation of errors are related to the level and severity of the curvature. Abrupt apical curvatures and double curvatures (the S-shape) can beespecially difficult to negotiate and shape. In addition, canals that join or diverge always deviate from their initial path. It is important to realize that the resulting angle is often different for the canals involved. Besides complicating the process of instrumentation, root canal curvature results in several other procedural challenges. For example, needle placement and irrigant exchange for the removal of debris are more difficult beyond the curve. Related to visual aids, inspection with the operating microscope is restricted to the straight part of the root canal (above the curve). The creation of straight-line access, the use of flexible endodontic instru- ments and proper file bending and use are essential measures to prepare curved canals (see further below).
Cross-sectional shape and diameter
Root canals are round, oval or irregular (ribbon-shaped) on cross-sectional view. Oval and irregular shapes are common in the coronal two-thirds of root canals, whereas the round variant is often restricted to the apical part. Oval cross-sectional shapes are often found in the distal root canals of mandibular molar teeth and in mandibular premolar and incisor teeth. In an investiga- tion of 180 teeth representing all tooth types, Wu and co-workers detected oval root canal shapes in 25% of the specimens investigated. When two or more canals are present in the same root, anastomoses and fins (lateral extensions) are frequently observed. Some root canals may present with extreme cross-sectional shapes. This applies especially to the C-shaped canal, which is more prevalent in certain ethnic groups. Oval and irregular cross-sectional shapes certainly do challenge root canal cleaning and shaping. Parts of the lateral anatomy are often out of reach because most end- odontic instruments are designed to stay centered. Root canal diameter is related to the concept of conicity or “taper”. When looking at the root canal diameter at consecutive levels along the root, an idea of the overall conical shape is obtained. The exact value for diameter and taper will, however, vary for each point along the central axis. Usually root canals are wide in the coronal part and relatively narrow apically. Immature teeth and roots that are liable to some type of resorption may appear different. Also, deposition of reparative dentin may alter root canal diameter generally or locally (i.e. at sites of prior pulpal irritation).
Apical configuration
In their apical one-third, root canals are often narrow and more or less curved. Their “portals of exit” can have the typical appearance of a foramen apicale (with or without accessory canals) or the sporadic appearance of an apical delta. Classical work carried out by Kuttler demonstrated that, on average, the nar- rowest point of the canal (i.e. the apical constriction) is situated
Physiologically and pathologically induced changes
Throughout the life of a tooth with a vital pulp, oblitera- tion and narrowing of parts of the root canal system can occur owing to physiological aging and reparative pro- cesses. Low-grade irritation, such as slowly advancing dental caries, root surface exposure due to periodontal disease and acute or chronic trauma (e.g. accidents involving teeth, cavity and crown-related restorative procedures, traumatic occlusion and bruxism) may evoke such pulpal responses. In teeth with a loaded history (e.g. in elderly individuals) the deposition of reparative dentin can be particularly substantial. The mineralization process usually begins in the coronal part of the root canal system and proceeds apically. Thus, there may eventually be generalized accumulations of hard tissue on the wall of the root canal, narrowing the lumen to such an extent that the canal appears obliterated. Mineralizations may also take the form of pulp stones that are free within the root canal system or attached to the root canal wall. In the pulp chamber of molars the hard tissue tends to form on the roof to shorten the chamber size in a vertical dimen- sion making it difficult to localize root canal orifices upon access preparation. Besides hampering exploration of root canals, canal negotiation is a real challenge in these cases and the creation of a ledge, and subsequent root perforation constitutes a distinct risk.
Procedural steps
Preassessment
After clinical examination and diagnosis, preassessment of the case is imperative, including the construction of a mental image of the tooth to be treated. The preopera- tive radiographs are carefully examined and the external root surface is palpated or probed. Special attention is paid to: • a possible inclination of the tooth; • the cervical contour of the (residual) tooth crown; • the size of the pulp chamber; • the amount of obliteration and narrowing of the root canal system; • the integrity and course of the periodontal ligament; • the number of roots (and root canals); • length and diameter of the root(s); • the degree of root canal curvature (as far as possible).
Field isolation
Asepsis is a strict requirement for non-surgical e ndodontic treatment. Bacterial contamination of the operation field (the tooth crown and root canal system) is avoided by using rubber dam isolation and disinfection techniques, sterilized instruments and decontaminated materials. Every experienced clinician will confirm the view that the use of rubber dam facilitates rather than complicates endodontic treatment. Well-informed patients will accept the use of rubber dam and will appreciate the effort for quality and comfort.
Access opening
Proper access is the key to successful cleaning and shap- ing of root canals. While the entire roof of the pulp chamber often has to be removed, the outline of the access cavity is dictated by the number and position of the root canal orifice. Initial penetration into the pulp chamber should be undertaken using a bur in a water-cooled high-speed handpiece. Normally a safe direction to avoid misalign- ment and excessive damage to the crown is towards the widest root canal (e.g. palatal root in upper molars and distal root in lower molars). Once into the pulp chamber, overhanging margins must be removed. One may then shift preparation technique to a slow-speed handpiece without water coolant in order to enhance visualization. Useful burs in this phase of the access preparation are long-shanked round burs. In cases where localization of the pulp chamber appears challenging, rubber dam placement may be delayed until an opening has been found. The advantage of this measure is to get indica- tions on root inclinations and furcation grooves by prob- ing the external root surface. Root surface probing can be especially useful in cases of premolars with multiple
canals in the buccal root, and in cases of preparation through a metal crown. Complete removal of the existing coronal restoration is advised in most cases because it: allows better radiographic interpretation of the anat- omy of the coronal part of the root canal system; allows complete inspection of the residual crown (e.g. for the detection of possible fractures); solves marginal leakage; detects hidden caries; provides a better view of the pulp chamber in the presence of more refracted light; prevents inconsistent readings when using electronic apex locators; prevents metal filings from entering the canal. Once uncovered, the floor of the pulp chamber can be examined like a map in order to explore the root canal system anatomy. Care should be taken to avoid damag- ing the floor of the pulp chamber as the root canal orifices are to be sought along the groove system. A straight sharp-tipped explorer is handy here. In cases of gross depositions of mineralized tissue, exploration of the con- necting grooves can be done using ultrasonically pow- ered instruments (used at low power settings and with a light touch) or with long-shanked round burs in a slow- speed (800–1000 rpm) handpiece. Slight differences in color between the walls of the pulp chamber and the floor assist in finding the root canal entrances Cavity walls are adjusted to reflect the operating light and to allow straight-line entry to the root canal(s). For example, in order to locate the MB2 (second canal in the mesiobuccal root) in maxillary molars, the access cavity should be created with a clear extension towards the mesial side. All cavity walls are then smoothed and connected with the orifice(s) of the respective canal(s). The latter simplifies re-entry into the canal, especially when irrigants are present, without buckling the tip of small files. Of course, access cavity preparation should be performed after careful examination of the undistorted preoperative radiograph(s) and with respect for the integrity of the crown.
Initial root canal preparation (coronal preflaring)
As a general rule, the removal of root dentin should be centered, i.e. with respect to the initial root canal anato- my. In the coronal one-third of a curved root canal, how- ever, this concept is intentionally ignored. Indeed, by carefully relocating the root canal orifice (using for instance Gates–Glidden burs), the degree of mid-root curvature is decreased without weakening the tooth.
The creation of a “straight-line access” is mandatory to avoid obstruction of the intracanal view, root canal straightening and instrument separation. Regarding the adopted technique for instrumentation, one makes a distinction between file movement and shaping approach. The latter is related to the instrument sequence and file insertion depth. In general, a coronal- to-apical approach is advised because: • coronal preflaring allows more control during subse- quent preparation of the middle and apical one-thirds; the risk of canal blockage, ledge formation and instru- ment fracture is reduced; working length determination is more precise after coronal preflaring.
In the modified double flared approach, for instance, the coronal portion of the root canal is flared first (from orifice to curvature). In cases of curved and narrow canals, the root canal is gradually explored and flared first, and care is takeot to over- load any specific instrument as it may create a ledge. An error that is commonly made during this initial proce- dure is to overuse files, especially the smaller sizes. Instead of wasting one file after the other, sizes 06–10 K-files should be used in combination with flexible K-files sizes 15–30 to cut more coronal shape in big increments (i.e. the “serial step-back negotiation”). The smaller-sized K-file, which was resisting further advance- ment, may then advance deeper into the root canal because the shank portions are released from binding. In all situations, the act of recapitulation represents a safe and effective strategy for root canal negotiation.
Methods to establish working length
Determination of the apical limit for preparation of root canals (working length) is a most critical procedural step; canals should be instrumented neither too short nor too long. Instrumentation short of the canal exit risks leaving inflamed tissue and infectious elements in the root canal space, while instrumentation beyond the apical foramen may force infectious debris into the periapical tissue compartment and cause an endodontic flare-up. Overpreparation may also pave the way for overfilling with lingering foreign body reaction and incomplete regeneration of the supporting tissues as a result Generally, it is believed that the apical termi- nation of the intervention should be at the apical con- striction because this location indicates the junction between the periodontal and pulpal tissues. The working length may be determined in a number of ways but, whatever method is used, it must be accurate, repeatable and carried out easily.
Measuring working length by radiography
Undistorted periapical radiographs taken with a film- holder and the paralleling technique prior to treatment allow only for an approximate estimation of the length of canal preparation to be taken. For more exact measure- ments a precurved instrument with a silicone stop on the shaft is placed into the root canal short of the inspected length. If coronal preflaring of the root canal has been done prior to working length measurement then tactile sensation can be used to feel for the apical constriction. However, there will be no proper tactile feedback if the apical constriction has been destroyed (e.g. root resorp- tion), if there is immature development of the root end, or if the root canal is narrow along most of its length. The root canal under exploratioeeds to be widened to a size 10–15 for the instrument tip to be seen clearly on the working length radiograph. If the radiographic image shows the tip of the instru- ment to be more than
Measuring working length by electronic apex locators
Suzuki discovered in dog experiments in 1942 that the electrical resistance between the periodontal l igament and the oral mucosa was a consistent value of 6.5 kΩ. The same observation was made in humans by Sunada in 1962, thus leading to the introduction of the resistance- type apex locators. Unfortunately these early devices often yielded inaccurate results when electrolytes, exces- sive moisture, vital pulp tissue, exudates or excessive bleeding were present in the root canal. With the introduction of the impedance-type EALs in the late 1980s and especially the frequency-dependent EALs in the early 1990s, a more accurate canal length measurement was obtained in these various canal conditions. Frequency-dependent EALs use more advanced tech- nology and measure the impedance difference between two frequencies or the ratio of two (or more) electrical impedances. Using EALs, one side of the electrical circuit is connected to the root canal instrument and the other electrode to a lip clip that connects with the oral mucosa.
As the instrument moves towards the apex, the impedance difference (or ratio) becomes greater and shows the greatest value at the apical constriction, allow- ing for a measurement at this location. Some devices need to be calibrated when the instrument is inserted into the coronal portion of the canal. The accuracy of contemporary EALs is very high (approximately 90%) with a tolerance level of
Paper point evaluation
A paper point placed into a dried canal and extended beyond the working length will absorb tissue fluid at the apex and, if withdrawn immediately, will allow measure- ment of the dry portion of the point, thereby providing some indication of the working length.
Final canal preparation
As outlined in Chapters 4 and
The amount of preparation to be carried out in the apical one-third of root canals is the subject of controversy. Some people believe that it is unnecessary to widen the apical preparation because coronal preflaring and apical patency confirmation will allow the irrigant to reach and clean the apical part of the root canal. Most clinical experts, however, advocate rather large (size 35 or h igher) but centered preparations in order to remove infected dentin in the apical few millimeters of the root canal. Certainly the widening of the apical part of the root canal to a reasonable size and taper after prepa- ration of the coronal and middle sections allows easier placement of the needle for irrigation and also of the gutta-percha cone for obturation. Various techniques may be applied. In the modified double flared approach the second flare is obtained with a step-back sequence. This step-back means the smallest instrument is used to the working length first, and then instruments with increasing tip diameters are used more coronally in fixed increments. Instead of this step-back sequence with 2% tapered instruments, GT hand files can be selected for a crown-down sequence to flare the apical portion more easily. In Ni–Ti rotary instrumentations, stainless steel 10–20/.02 K-files (hand-held, flexible) are first used to cre- ate a glide path to the working length to minimize the stress on the subsequent Ni–Ti rotary files. These files can then be used safely in a crown-down sequence (see further below). For the final file selection, apical gauging is advised since the initial diameter of the apical constriction varies for different canals. This procedural step means the insertion of an instrument to the working length after coronal and apical flaring (to avoid interference of the upper part). The gauging file is then fitted to the apical constriction (without rotation) to note any resistance. If so, the diameter for the final preparation is thought to have been defined. In most cases, one selects a few sizes larger because the cross-sectional shape of the root canal can be oval with the smallest diameter measured.
Endodontic instruments
Traditional systems
For decades, instrumentation of root canals was solely performed using stainless steel (and nickel–titanium) hand files in various forms. All these files have cutting flutes
in shape. Flexible K-files are essentially similar to K-files except that the cross-sectional design is such that the instrument is able to flex more than the conventional K-file. They may be made from stainless steel alloys or nickel–titanium. Hedstr?m files are manufac- tured by grinding a tapered blank that has a round cross- section. Machining produces a spirally tapered series of cones with cutting edges at the base of each cone. The instrument is designed for a filing motion and cuts only when being withdrawn from the root canal. If used in rotation it may break relatively easily because of the small core diameter. The use of Hedstr?m files is mainly for flaring root canals, especially oval- shaped canals. They can also be used for removal of f ractured instruments and gutta-percha in retreatment cases. Hedstr?m files in larger sizes are more rigid and may cause ledges or strip perforations within curved root canals and should therefore be used with great caution. Gates–Glidden burs are, in effect, engine-driven r eamers. These burs come in various sizes from ISO 050 (size 1) to ISO 150 (size 6) and are available in
Nickel–titanium rotary systems
Nickel–titanium: a super-elastic alloy
The super-elasticity of Ni–Ti is based on stress-induced martensitic transformation. The application of outer stress causes martensite to form at temperatures higher than the transition temperature . When the outer stress is released, the martensite transforms back into austenite and the specimen returns back to its original shape. As a result, super-elastic Ni–Ti can be strained several times more than ordinary metal alloys without being plastically deformed, and with relatively light force (low elastic modulus).
File design: the concept of greater taper
Because the super-elasticity of nickel–titanium diminish- es the connection between instrument diameter and stiffness, the use of rotary files with a two- to six-fold taper (and large diameter) has become possible. These Ni–Ti rotary files are mainly manufactured for use in a torque-controlled handpiece at constant speed (rpm). Besides variation in taper, the existing Ni–Ti rotary files have various designs for instrument shaft (including blades and grooves). The shaft design is adapted to be used in continuous rotation. Most systems flatten, modify or shorten the cutting edges and vary the depth of the groove, helical angle, pitch or taper to prevent the instru- ment from screwing and binding in the canal wall. The original ProFile instruments were some of the first Ni–Ti rotary instruments on the market. Their cross- sectional shape is made by machining three equally spaced U-shaped grooves around the shaft of a tapered Ni–Ti wire. For this “classical” design, a space remains without being ground between each groove, providing a “radial land area”. Without a blade projecting outwards from the middle of the shaft, this flat area prevents the file from locking in the dentin, while cutting occurs through a planing (acting passively) action. By contrast, some of the latest systems show sharp cutting edges (act- ing actively) resulting from a triangular cross-sectional design. Such an instrument, the so-called ProTaper, also combines multiple progressive tapers within the same shaft. The existing rake angle can be verified in accordance with shaft design. The rake angle can be seen as the angle between the leading edge of a cutting tool and a perpendicular to the surface being cut. A rake angle can be negative, neutral or positive. In general, conventional endodontic instruments have a slightly negative rake angle and most Ni–Ti rotary files have a slightly negative or neutral rake angle.
Regarding the instrument tip, one could summarize that most contemporary files, both hand-held and engine- driven, have an acceptable non-aggressive tip design and there should be little concern over tip geometry in the selection of files (ISO/ANSI guidelines). Most Ni–Ti rotary files have rounded non-cutting tips that serve as a guide within the canal. Unlike the tip, the instrument shaft retains its cutting action; only the transition angle at D1 is modified. Concerning size of the tip, most manu- facturers of Ni–Ti rotary instruments make use of real increments (in 50 μm), equal to the standard guidelines used for the production of stainless steel hand files. The file design of the Lightspeed system deserves attention. These instruments are modified so that a short cutting zone remains apically, the so-called apical action design. The files are used for apical prep- aration and do not cut over most of the canal length because of the existence of a smooth small-diameter shaft that also enhances instrument’s flexibility. Apical action designed instruments prepare the apical portion with less transportation and less dentin removal than other instruments. Nevertheless, as with other Ni–Ti instruments there are risks for instrument fracture and special training is needed.
Instrumentation techniques
Hand instrumentation
The modified double flared approach
As a result of the 2% taper standardization for hand files, a final shaping objective with greater (4% or higher) taper can only be achieved using a series of files with different tip diameter at various levels in the root canal. Besides the shap- ing approach, how the selected instruments are moved is also critical to the result. Well-known file movements include the filing (or push–pull) motion and the reaming motion (rotation).
File manipulation: the filing and reaming motions
The filing motion is especially suitable to the Hedstr?m file. It removes dentin from the root canal wall when the instrument is inserted to a given length and then pressed against the canal walls at the same time as it is drawn coronally. This action is performed and resumed with certain amplitude. There are difficulties with this method, including the tendency to grooving into the dentinal canal wall, without a conscious effort being made to move the file circumferentially, and packing of debris ahead of the instrument tip, which may block the root canal. The push–pull motion is also possible with K- files but should be restricted to size 15 (or less) as rasping with larger instruments may cause iatrogenic damage. The reaming motion denotes a clockwise or counter- clockwise rotation of the instrument in the root canal. It is the preferred method for reamers and (flexible) K-files. Watch-winding is a clockwise/counter-clockwise rota- tion of the instrument through an arc of 30–90° while advancing the instrument into the canal. The reciprocat- ing back and forth rotational movement alternately pulls the instrument into the canal (clockwise), and then (counter-clockwise) cuts the engaged dentin. At a certain point watch-winding will not advance the instrument further into the canal. In many cases, three to five push– pull filing strokes will loosen the shaft and allow watch- winding to advance the instrument further apically. The watch-winding method is less aggressive than the origi- nal “quarter turn–pull” and should be used with light apical pressure. With precurved stainless steel instru- ments this technique is extremely useful for initial nego- tiation of root canals, especially those that are severely curved or narrow. The balanced force motion was devised by Roane and co- workers and endorsed by Charles and Charles on the basis of a mathematical model. This technique is essentially a reaming action using clockwise movement to insert the file and counter-clockwise movement to remove dentin. The file is placed into the root canal until it binds against the wall. The file is then rotated through 60–90° with light apical pressure. This creates threads within the dentin. The instrument is moved counter- clockwise through 120–360° with mild apical pressure, which crushes and breaks off the dentin threads and enlarges the root canal. A final clockwise rotation allows
flutes to be loaded with debris and removed from the root canal. This technique has been shown to be efficient and less prone to cause iatrogenic damage. The technique must be used with flexible K-files that are not precurved. A technique of reverse balanced force instru- mentation has been developed for use with GT hand files where the flutes of the shaft are machined in an opposite thread to normal files.
Nickel–titanium rotary instrumentation
The crown-down sequence
In general, Ni–Ti rotary systems advocate preflaring of the coronal portion of the root canal and relocation of the canal orifices with Gates–Glidden burs prior to deeper instrumentation. Preflaring can also be carried out with Ni–Ti rotary files such as orifice openers or accessory files from the system. These instruments for initial shap- ing tend to produce centered preparations, however; anti-curvature relocation of the canal orifice is more dif- ficult to obtain. Some of the newest systems (e.g. ProTaper) seem to behave differently. Their active cut- ting design, lacking radial land areas, removes dentin more selectively and allows coronal relocation.
Meticulous manipulation of this file is, however, essential to get the particular effect and to avoid strip perforations. After coronal preflaring, Ni–Ti rotary files are used in a crown-down sequence (coronal to apical) up to 3–4 mm from the working length as estimated on well- angulated radiographs (NB: do not forget to create and confirm glide path first). A first concept therefore adopts the use of a constant taper (typically .06) while reducing tip size throughout the sequence, whereas the variably tapered file concept changes this taper in the sequence of canal instrumentation with or without changing tip size. The latter maximizes cut- ting efficiency by increasing the force per unit area of the file against the canal wall, whereas the former runs the risk of a taper-lock. Proceeding further on this idea, the ProTaper was i ntroduced, a Ni–Ti file design that combines multiple progressive tapers within the same shaft. Once the working length determination is complete and a glide path established, the delicate preparation of the apical portion is continued with Ni–Ti rotary files at the working length. Some systems promote the use of tapers up to 8% or 10%, while confining tip size (e.g. size 20 for small canals). Most concepts, however, begin with 4% tapered files, while gradually increasing tip size up to the final apical preparation diameter. Next, the body of the preparation is finished with 6% tapered files at the working length. In general, all Ni–Ti rotary systems follow a compara- ble approach. As important differences do exist it is advisable to follow the specific instructions given by the manufacturer. The Lightspeed system, however, needs further consideration. As men- tioned before, this system incorporates a smooth flexible shaft with a short cutting head. As a result of the no-taper design, flare can be achieved only using a step-back sequence with numerous instrument sizes or another file with increased taper to refine the root canal walls before obturation.
Continuous reaming motion
The advantageous qualities of the Ni–Ti alloy are maxi- mally exploited if the instruments are continuously rotating over 360°. As mentioned before, Ni–Ti rotary files exist in an austenitic phase that transforms to a mar- tensitic structure on stressing at a constant temperature. In this stress-induced martensitic phase only a light force is required for bending. Limited and constant stress is needed for optimal performance. This is accom- plished by using constant speed (rpm) and light apical pressure. In this way, the Ni–Ti rotary file will operate in the horizontal part of the stress/strain curve, showing little restoring forces and no plastic deformation. Ni–Ti rotary systems have a speed range (rpm) and torque lim- its (N/cm?) for optimal performance that are specified by the manufacturer for each file separately. Above the allowed torque, plastic deformation and instrument fracture may occur. If the torque-limit value is set too low, the file will stop cutting even when safe. Increased speed (higher rpm) seems to increase shaft stiffness. For that reason, a lower rpm may be required to instru- ment small curved canals. The use of automated handpiece systems for root canal preparation has accelerated since the introduction of Ni–Ti rotary files. In the past, some stainless steel files were used in engine-driven (reciprocal) rotation, but the incidence of canal aberrations is high. Although variations exist, Ni–Ti rotary files are generally used in a high-quality air reduction handpiece (with or without torque control) or, better (as the flow of air can hardly be controlled and the reported wear for air reduction handpieces is high), an electric motor whereby a feed- back c ircuitry compensates for torque to maintain a con- stant speed, and a suitable speed-reducing handpiece with a small head. The settings of the manufacturer are preprogrammed, and can be regularly updated or changed. The use of all-in-one systems (i.e. an electric motor with an integrated apex locator) should be dis- couraged because such devices operate on batteries and do not allow coupling with hand files. In addition to the continuous reaming motion, the operator should follow the specific method of use (e.g. brushing motion, “pecking” movement, smooth steady pressure, etc.) and observe the recommended sequenc- ing of files. All file types must be used with a light touch and minimal apical pressure. In addition, one must not rotate the file for too long in the canal and during this period of time, the instrument must not stop rotating. The use of an irrigating solution while cleaning and shaping the root canal system is an accepted practice. Irrigation plays an important role in lubricating the canal and in facilitating chip and debris removal. Some irrig- ants also serve the very important purpose of root canal disinfection.
Limitations of root canal instrumentation
Nickel–titanium rotary versus stainless steel hand files
The use of nickel–titanium under continuous rotation enables innovative design features, and it may eliminate some traditional difficulties that are associated with c onventional root canal instrumentation. Certainly, Ni–Ti rotary instruments, if used properly, can achieve a final root canal preparation that conforms to the general shape and direction of the original canal. Because of the reduced restoring forces developed by Ni–Ti rotary instruments, it has been reported that more centered root canal preparations are created than with hand instrumentation. The magnitude of trans- portation caused by Ni–Ti rotary files is small with a simi- lar direction at the end-point of the preparation to that found with stainless steel hand files (i.e. the outer aspect of the curve). At the mid-curvature level, transportation has been reported towards the inner and outer aspect. In general, root canals with more severe curvature are wider after instrumentation with the main difference being a greater amount of dentin removal at the outer (convex) aspect of the curve. The differences between Ni–Ti rotary and stainless steel hand preparation are more pronounced if the apical preparation diameter is larger than size 30. There are only small discrep- ancies among the various Ni–Ti rotary systems at different horizontal levels. Using stainless steel hand files iarrow and curved canals, a size 30 preparation reflects what most clinicians regard as an instrumentation end-point. Using Ni–Ti rotary instruments, the more desired size 40 preparation has become common, since the super-elasticity of Ni–Ti diminishes the connection between instrument diameter and stiffness. The instrumentation of the apical matrix to a larger size incorporates more anatomical irregularities and provides more irrigant exchange in the apical one- third. Ni–Ti rotary instrumentation is faster (shorter prepa- ration times) than stainless steel hand instrumentation and operator’s fatigue is reduced. Differences between various Ni–Ti rotary systems are more likely the result of variations in preparation technique than any differences between instrument performances. Greater taper systems that are used by moving up and down the numerical sequence in a crown-down manner to flare the canal until the smaller files reach working length have the widest percentage variation in time. The anato- my of some root canals requires moving up and down the sequence several times while in other canals working length is reached very quickly. In addition, the f requency of irrigation also influences preparation time. Occasionally, Ni–Ti rotary systems speed up the treat- ment considerably, so that the effective time for the irrigant is strongly reduced. If unnoticed, this fact may undermine the extent of chemical cleaning and disinfec- tion. Regarding the direct efficacy in removal of bacteria it is important to notice that no difference was found between hand and rotary instruments. With the launch of Ni–Ti rotary systems, too much credit was given to these systems as being a solution for root canal preparation on their own. Since then, a com- bined approach of Ni–Ti and stainless steel preparation has been advocated. The combined approach is especially needed in difficult cases and in most retreatment cases. In this way only, procedural errors can be avoided and the aberrations that are present can be corrected. More than ever, mental awareness is needed. Much of the result will depend on the clinician’s experience (the “feel”), visualization facilities (radiography as well as direct, magnified and illuminated vision), and sound concepts, rather than on ready-for-use recipes. Indeed, the “one magical sequence” does not seem to exist. Those who have gained some experience in the use of Ni–Ti rotary files will confirm that each file system has its own special advantages and disadvantages, and that particu- lar rules for its usage need to be followed. Eventually, instruments of different file systems can be combined using different instrumentation sequences to manage individual clinical situations according to a hybrid concept. Besides its biocompatibility and excellent corrosion resistance, Ni–Ti is, however, an expensive alloy that is difficult to manufacture and mill. Machining the original Ni–Ti wire should be conducted with carbide burs or silicone carbide wheels under active highly c hlorinated cutting oil involving light feeds and slow speeds. The surface of early Ni–Ti files was rough with grooves and irregularities, which could lead to a ccelerated wear, fatigue and breakage. Nowadays, most manufacturers have overcome this problem, and they perform metal treatment such as cryogenics or electropolishing. Given the high price per instrument, the incorporation of Ni–Ti as used in modern endodontics has increased the proce- dure costs dramatically. Therefore, patients should be informed and the highest possible level of care should be provided.
Limited reach versus unwanted dentin removal
Root canals following Ni–Ti rotary instrumentation for the most part show an oval or round preparation with most of the contours prepared. Nevertheless, specimens can present with unprepared areas in all thirds of their root canal system when a round preparation is produced in the center or at one side, leaving the remaining root canal walls uninstrumented. Especially flexible and passively cutting Ni–Ti rotary systems have deficiencies in the preparation of oval root canals because their super- elasticity and planing action do not allow controlled preparation of the buccal and lingual extensions. For these systems, canal preparation characteristics may be dictated more by anatomy (i.e. cross-sectional shape and curvature) than by the difference in instrumentation method. For the ProTaper system, which is more actively cutting, a special instrument motion called brushing has been recommended to deal with oval canals and to relo- cate the root canal orifice. In the middle and a pical one-thirds of the root canal, the use of this triangular design does not seem to negatively affect centering abili- ties. However, care should be takeot to instrument the apical foramen with more actively cutting blades to avoid zipping. Furthermore, the finish- ing files of the ProTaper system should not be used with an extended pecking movement to avoid root canal transportation.
Risk of instrument fracture
Instruments may fracture as a result of misuse or over- use. Before and during treatment, files should be checked carefully to ensure that the cutting flutes are not dam- aged. Regarding Ni–Ti rotary instruments, fracture can occur without any visible signs of previous permanent deformation, apparently within the elastic limit of the instrument. Visible inspection of the file, therefore, is not always a reliable method for evaluating used Ni–Ti instruments. Theoretically, the phenomenon of repeated cyclic (metal) fatigue may be the most important factor in sepa- ration of Ni–Ti rotary files. When instruments are placed in curved canals, they deform and stress occurs within the instrument. The half of the instrument shaft on the outside of the curve is in tension and the half on the inside is in compression. Consequently, each rotation causes the file to undergo one complete tension– c ompression cycle. Obviously, stress levels are the great- est in the area of curvature. A more severe bend (i.e. a smaller radius with an abrupt curve) creates greater stress and larger instruments will experience greater stress than smaller instruments when confined to the same curved root canal shape. Considering cycle fatigue as a contributor to instrument fracture, larger instruments (size, taper or core) should not be considered safer or stronger in practice. Preflaring and relocating the root canal orifice, thus creating straight-line access, can decrease the severity of curvature. Torsional loading during rotational use is another variable to consider. The amount of torque applied to the instrument mainly depends on the manipulation of the file (e.g. the amount of apical pressure) and its shaft design. The crown-down sequence generates lower torque and lower vertical forces, although these elements also depend on the shape of the individual canals. In this regard, radius of root canal curvature is the most impor- tant factor in determining the torque value. If two canals have the same angle of curvature but have a different radius, then the one with smaller radius has the more abrupt canal deviation and results in higher torque on the file. Shaft design itself has an influence on torsional loading because cutting blades could act as stress con- centrators, potentially resulting in more rapid crack initi- ation. On the contrary, radial land areas contribute to the strength of the instrument by the relatively large periph- eral mass. The same remark can be made on the diameter of the central core. Adequate resistance to torque failure is also obtained by increasing instrument taper and size. The introduction of the operating microscope and ultrasonically powered tips allows dentin to be removed precisely so that in many cases fractured instruments may be freed and subsequently removed. Unfortunately the canal is often overprepared during this procedure. If an instrument fractures during root canal treatment, the patient must be informed and the progress notes suitably annotated.
