Filling materials for temporary and permanent root canal obturation. Technique root canals in temporary teeth. Root seal. Technique root canals in permanent teeth with immature roots. The concept apeksohenez and apexification.

Endodontic Obturation

Although periapical healing starts after Root canal cleaning, shaping and disinfection is done, it is an accepted scientific fact that good obturation is needed for it to stay healed over the years. An Obturation should :

• Prevent recolonization of the root canal system with microorganisms that can produce destructive functions by the host tissues

• Prevent Periapical disease in teeth with vital pulps.

• Prevent Periapical Disease in teeth with

necrotic pulps and no radiolucency

• Heal Periapical disease in teeth with obvious clinical and radiographic symptoms

Proper root canal filling should achieve three dimensional obturation of the endodontics space to prevent micro organisms from entering and reinfecting the root canal system and to prevent tissue fluids from percolating back into the root canal system to provide a culture medium for any residual bacteria. It should seal all “portals of exit” to impede any sort of communication or exchan- ge between the endodontium and periodontium.

It is clear from the objectives that the most critical area is the apical terminus of the root canal. While attempting to provide a hermetic seal in this region, we have to keep in mind that when heated gutta percha cools, always there is contraction. Even though thermo plasticized gutta percha techniques are fast and good enough for obturating the body of the root canal, it cannot give a hermetic seal in the apical third.

Another important consideration is that if a post space is to be prepared or in the event of a re- root canal treatment, we should be able to remove the obturation without jeopardizing the integrity of the remaining tooth structure. So it is preferable to use a technique that doesn’t leave a ‘difficult to remove’ carrier in the root canal.

Obturation Techniques:

-The most commonly used techniques are lateral condensation and vertical compaction using gutta percha.
-Warm gutta percha techniques:

·  Thermocompaction technique (McSpadden)

·  Ultrasonic Compaction technique

·  Thermoplasticized injection techniques (Obtura and Ultrafil)

·  Gutta percha carrier systems (Thermafill and SimpliFill)

Lateral condensation :

Lateral condensation is a good technique where it is indicated, and it has withstood the test of time. 
Root canal spreaders for lateral condensation:

Vertical condensation:

Advocated by Herbert Schilder, vertical condensation requires a set of variable diameter pluggers.

Warm gutta percha techniques:

1.JS Quick-Fill 
Alpha phase gutta -percha, on special design titanium carrier, JS Quick-Fill gives you a control, smooth obturation all in a single step.

• No heating units or open flame.

• Works with friction heat.

• Fit in your low speed handpiece.

• Chairside efficiency.

Disadvantages:
The operator cannot control extrusion of obturating material

• The instruments can break

• If the file is turning in reverse, it can screw itself into the canal and periapical tissues

 

2. Thermoplasticized injection techniques (Obtura and Ultrafil) 
Length control is a disadvantage

• Canal preparation must be sufficient to permit placement of the needle to within 4-6 mm of the apical preparation

The Obtura II Warm Gutta Percha System 
This warm gutta percha-delivery system can be quickly and efficiently incorp-orated with all down-packing techniques. It is helpful in cases of internal resorption. 

3. System B – The Continuos Wave of Condensation (L. S. Buchanan, 1987) The System B heat source can monitor the temperature at the tip of its heat carrier device, delivering a precise amount of heat for an indefinite time without overheating the gutta-percha. These heat carriers are designed to soften the gutta-percha and at the same time condense it. The Continous Wave Technique requires only one plugger versus four or five when utilizing the Vertical Condensation Technique as described by Dr. Schilder.

Sybron has just come out with the New Cordless System B, see the pic below
SimpiFill obturation :-

SimpliFill is the only carrier system where the carrier is not left in the canal. We all know that removal of carrier is not a pleasant job if we have to go for a post or a retreatment has to be done. It is the best hermetic seal you can obtain for your well prepared canal. When you push a 5mm of .02 tapered gutta percha into a 4mm of parallel apical preparation, you can understand that we are providing a cork like tight seal for the apical third.
To me the best advantage of SimpliFill is the opportunity to finish the post cementation in the same sitting. Because of the tight apical seal, I don’t have to worry that the vibration during the post space preparation may dislodge the gutta percha or compromise the apical seal. Equally important are cases with severely curved root canals and canals with curvatures in two planes. LightSpeed LSX system makes possible cleaning and enlarging the canal and it is only SimpliFill that can make sure the gutta percha reaches to the apical extent and a hermetic seal is provided. We can’t push a gutta percha point into such canals because they will buckle and won’t reach till the full working length 
HotShot Cordless Obturation device

• Completely cordless

• Multiple Uses on Single charge

• Easy to Clean

• Minimal heat tranmittance

• Wide range of temperature settings

GuttaFlow

GuttaFlow is a completely novel filling system for root canals that combines two products in one: gutta-percha in powder form with a particle size of less than 30 µm, and sealer. This new filling system works with cold free-flow gutta-percha, and uses an application system developed to enable an absolutely simple, safe and hygienic procedure. 
Gutta flow is by Coltene, same company also sells another injectable guttapercha obturation system name Ultrafil 3 D

Resilon

Resilon is a thermoplastic synthetic polymer based root canal filling material. Based on polymers of polyester, Resilon Material contains bioactive glass and radiopaque fillers. It performs like gutta-percha, has the same handling properties, and for retreatment purposes may be softened with heat, or dissolved with solvents like chloroform. Similar to gutta-percha, there are master cones in all ISO sizes and accessory cones in different sizes available. It can be bonded with tooth. There is still not enough evidence that Resilon performs better than Guttapercha. GP with lateral condensation continues to be GOLD standard for Endo obturation.

The Thermafil System- some call it Thermafilth, So Now it is called Guttacore

The Thermafil obturator consists of two parts, the carrier and the gutta-percha. The carrier is similar to a manual endodontic instrument without the blades, made from a special radio-opaque plastic. Carrier is coated with GP. Thermafil obturators have a taper of .04 and are available in various tip sizes starting from size 20 to 140. The chosen size is placed in a special oven and this warm cone is then pushed into canal giving a 3D filling. However cooling does lead to some shrinkage.

Disadvantages of Thermafil

This technique leaves a plastic carrier in the canal which poses a problem should you have to place post or retreat the case.
Special oven (therma prep plus oven) is required to heat thermafil cones.
In curved canals carrier usually gets stripped of GP in curvature.
You needs special technique and time to remove nasty carrier in cases which need post core or retreatment. 
Many companies have copied this product, “Stay away from Thermafil and its likes”
Thermaflo is similar to Thermafil

SmartSeal- Obturation system with claim that on contact with canal fluids the obturation point will expand and seal the canal. 

Calamus 3 D obturation System by Dentsply

Calamus offers downpack and backfill obturation techniques. With the Pack and Flow positioned side-by-side, dentists can move smoothly from one step to the next. Use the Pack to create an effective and dense apical plug, then use the Flow to deliver the gutta-percha backfill at the perfect temperature and flow rate. Each ergonomically-designed handpiece features a 360-degree activation cuff providing ultimate control whether delivering a smooth, continuous expression of gutta-percha or successfully placing an apical plug.

Elements Obturation Unit by Sybronendo

The Elements Obturation Unit combines our System B™ technology with a motor-driven extruder handpiece to make obturation efficient, predictable, and accurate. From downpack to backfill, the Elements Obturation Unit puts the Continuous Wave of Condensation Technique into one simple-to-operate device that takes up only 1/3 the space of two separate machines. 
Ultrasonic lateral condensation:

Example technique (use common sense)Insert ultrasonic spreader (F 88 009 –S04, Satelec by Acteon Group, Mйrignac Cedex, France)alongside the master cone and activated with an ultrasonic unit (P-MAX, Satelec) for 3 seconds, push apically, and activate again for 3 seconds. Repeat until the spreader reaches 3mm short of the working length. Briefly activate (setting 3-5) and remove spreder and put a size 35 standardized gutta-percha cone, coated with sealer.Continue condensation until the canal is filled. Excess gutta-percha is seared off and the heated gutta-percha vertically condensed with an ultrasonic plugger (F 00 250-5, Satelec). 

Endodontic sealers

Sealers play an important role in the obturation (filling) of a root canal. The sealer coats the walls of the canals and fills the space between the root canal filling material and the root. Their antimicrobial activity likely plays an important role in the overall documented success of endodontic therapy.

There are many kinds of endodontics sealers. They can be grouped into these categories:

1. Zinc Oxide-Eugenol

2. Calcium Hydroxide (Sealapex, CRCS, Apexit) 
3. Resin modified sealer (AH26, AHPlus, Diaket, Endofill, Resilon)

Sealers may contain different medicaments for antibacterial activity etc. KeyPOINT: Canal has to be cleaned well, dirty apex caot be healed by sealer.

Step 1: Check for Canal Patency

Recall the last file used used at the working length. In this case, the last file used at 24.5 mm was the 50 K-file. Place this file in the canal and check for canal patency one last time. The properly placed tip should elicit tugback in the apical region when an attempt to remove the file is made.

Step 2: Prepare Root Canal Cement

Prepare a mix of root canal cement using the cement powder mixture provided and a few drops of eugenol. Mix a small amount of eugenol with a small amount of powder using the spatula until the mixture is loose and tacky. When pulled with a spatula, the cement should stretch about an inch above the work surface. Continue to add small amounts of powder or eugenol until the desired consistency is attained. When fully mixed, the cement should be smooth and

homogenous in texture, not grainy.

Step 3: Prepare to Fit Master Cone

When fitting the master gutta percha cone you must judge two parameters:

• approximate diameter at the apical constriction, (evidenced by tugback, or resistance at

the apex), and

• length at the apex of the root canal that you just cleaned or, working length.

 Both the tugback and working length must be correct. When tugback is evident, there will be resistance to removal and the cone will be engaging in the apical constricture.

• If the taper of the canal is too narrow for the gutta percha cone, the cone will not reach the apex.

• If the apex is blocked no tugback will be evident.

• If the apex is over-instrumented the gutta percha will extend beyond the apex.

• If the taper of the canal is large enough it will engage at the apical constricture.

Step 4: Select Master Cone

Place the last file to the working length and the last file that you shaped with on the bench top. Select a gutta percha master cone that reasonably approximates the shape of the prepared canal by estimating a size that lies between these two files.

Step 5: Measure Cone to Working Length

Using cotton pliers, remove a single gutta percha cone from the package and measure the cone to the working length.

Step 6: Place Master Cone in Canal

Place the gutta percha cone in the prepared canal up to the measured working length. If the point binds before reaching the measured length, select a thinner point. If the tip goes to measurement but does not elicit tugback, cut away 1 mm from the tip of the cone and try again. Continue to cut away the tip and try the cone again until tugback is achieved at the working length. Remember how much you cut away at the tip; you will have to cut this amount away for each subsequent cone that you use in filling the canal. After cutting away the tip, if tugback is achieved but the length is too short, the cone must be discarded and a new cone must be measured and adjusted to fit the canal.

When the tip of the cone binds exactly at the working length and offers resistance to withdrawal or, tugback, check the working length once more to verify that themeasurement is correct.

Remember, both the tugback and working length must be correct.

Step 7: Take Radiograph of Master Cone

With the gutta percha cone fitted in the canal, take a radiograph to confirm fit of the master cone. Develop your radiograph: in the lab, develop your radiograph using the automatic developing unit.

 Step 8: Lateral Condensation

Once the master gutta percha cone is fit, the canal is ready to be filled using the lateral condensation technique. Begin by placing the cement into the canal using the last working length file. Cover the file with cement and place it into the canal. Use the file to line the walls of the canal circumferentially, distributing the cement on the walls of the canal evenly, two or three times.

Step 9: Coat Cone with Cement

Using the cotton pliers, remove a gutta percha cone from the package and cover it with an even coat of cement. Place the cone in the canal it to the working length, until tugback is elicited. Extrusional cement may be witnessed with the unmounted teeth; this does not cause a problem. While no cement is irritation-free, once it sets the body accepts it and no long-term irritation persists.

Step 10: Spread Side-to-side

Place a D-11 spreader in the canal along side the cone. Apply pressure apically to push the spreader in as far as possible, and spread from side to side. This side-to-side or, lateral, spreading motion is the basis for the technique name, lateral condensation.

The D-11 spreader is available in both titanium and stainless steel. The stainless steel spreader may be used for straight canals; for curved canals the more flexible titanium spreader should be used. Stainless steel finger spreaders may also be used.

Step 11: Remove Protruding Gutta Percha

Remove the spreader and heat the long end Glick #1 instrument in the Bunsen burner flame. Place the heated Glick #1 in the canal to the floor of the pulp chamber and move the instrument from side to side, heating off the protruding gutta percha.

If the instrument is not hot enough, some of the gutta percha may be left behind. The instrument should be re-heated and the rest of the gutta percha removed.

Step 12: Compress Gutta Percha

Place the spreader into the canal as far as possible apically and spread from side to side, compressing the gutta percha and cement against the walls.

Step 13: Use Accessory Cones to Fill Canal

Repeat steps 13 through 17 using accessory gutta percha cones, until there is no more room in the canal for additional gutta percha

Step 14: Have No Gutta Percha on Floor

When the process is completed there should be no gutta percha on the floor of the chamber.Gutta percha should be placed in the canal only, and should not extend into the pulp chamber.

Step 15: Remove Remaining Cement

Use cotton to remove any remaining cement from the inside of the chamber.

Step 16: Take Final Radiograph

A final x-ray should be taken when the condensation is completed. In the clinic a final x-ray is taken without the rubber dam in place and with a final or temporary restoration in place on the tooth. Clinically it is possible to take a radiograph only in a bucco-lingual direction; however, in the preclinic, x-rays should be taken in both the bucco-lingual and mesio-distal direction. This will enable complete visualization of the root canal fill.

Develop your radiograph: in the lab, develop your radiograph using the automatic developing unit.

Indications:

• For indirect pulp capping and pulpotomy

• Apexifications and hard tissue formations

• Temporary or permanent filling material for infected root canals

• Treatment of root resorption

• Perfect cavity liner under all filling material

• Acid protection when applying etch technique

 Usage Instructions:

After root canal preparation, clean and dry the canal.

Insert the tip into the canal.

Fill the canal completely by pushing the syringe plunger while slowly withdrawing the tip.

Remove excess paste with a sterilized cotton pellet. Seal the canal using chosen Root Canal Sealant

 

Product Benefits
Improved radiopacity and increased antimicrobial effect	Non hardening paste with oil base
Prolonged release of calcium hydroxide helps create secondary dentine	Excellent bio-compatibility with no toxic effects on cells
Easy handling and easy direct application	Ideal for infected root canals and vital pulpotomies in deciduous teeth
Can be used in conjunction with gutta percha points and regular root canal sealants

 

Product usage instructions are included with the product. Packaging: 1 x 2g syringe 10 special endo capillary tips

Composition Calcium hydroxide   Iodoform Silicon oil and inert excipients

 Sealers

Regardless of the obturation technique employed, sealers are an essential component of the process. Sealers fill the space between the canal wall and core obturation material and may fill lateral and accessory canals, isthmuses, and irregularities in the root canal system.

The ideal properties of endodontic sealer are as follows:

1.   It should be viscous when mixed to provide good adhesion between it and the canal wall when set.

2. It should produce a watertight seal

3.  It should be radiopaque so that it can be visualized on X-ray.

4.   The particles of powder should be very fine so they can mix easily with the liquid.

5.  It should not shrink on setting.

6.  It should not stain tooth structure.

7.  It should be bacteriostatic or at least not encourage bacterial growth.

8. It should set slowly.

9. It should be insoluble in tissue fluids.

10.  It should be tissue-tolerant, that is nonirritating to periradicular tissue.

11.   It should be soluble in a common solvent in case removal of the root canal filling becomes necessary.

The most popular sealers are grouped by type:

1.  Zinc oxide-eugenol formulations(“Dexodent”,”Tubbli Seal”);

2.  Calcium hydroxide sealers(“Calasept”, “Apexit”, “Sealapex”);

3.  Glass- ionomers(“Ketac-Endo Aplicar” – ESPE);

4.  Resins (AH – Plus, AH 26).

Calcium Hydroxide Root Canal Therapy is the safe and effective way of maximizing the success of root canal procedure. CALASEPT can be delivered to the root apex in seconds. Calasept is pure calcium hydroxide powder mixed with sterile iso-tonic saline and packed in self contain Syringe. The Calasept System eliminates mixing and clean-up, provides a homogeneous pre-mixed paste consistency and ensures accurate placement, total sterility and full potency with every treatment.

The Calasept can be easily removed from the root canal by simple irrigation.CALASEPT stimulates formation of dentine bridges and hard tissue barrier in roots. It also used for stepwise excavation as the antibacterial effect on soft carious dentine provide this option.

CALASEPT has a very high content of calcium hydroxide (> 41%) giving a high concentration of hydroxyl ions. These generate the high pH value of 12.4 which has a pronounced bactericidal effect, i.e killing of bacteria.
High concentration of calcium hydroxide means long-lasting because the paste can release calcium ions for a long time.
CALASEPT is a ready-to-use paste in air tight syringes for direct application through the sterilized needles.

 

 

 

A wide variety are available. The calcium hydroxide materials (e.g. Sealapex)  or the eugenol-based sealers (e.g. Tubliseal) are perhaps the safest choice. Some would advocate the routine use of non-setting calcium hydroxide paste (Hypocal) as an inter-appointment medicament.

 

 Calcium hydroxide This is considered separately, because it has a wide range of applications in endodontics due to its antibacterial properties and an ability to promote the formation of a calcific barrier. The former is thought to be due to a high pH and also to the absorption of carbon dioxide, upon which the metabolic activities of many root-canal pathogens depend. It is also proteolytic.

Non-setting calcium hydroxide paste

Non-setting calcium hydroxide has a very high pH (of the order of 11) and has a potent antimicrobial action as a consequence. It is also a mild tissue irritant and has been shown to promote closure of root apex (apexification) in teeth where loss of vitality has occurred before normal growth and development of the tooth is complete. The rationale for its routine use as a medicament between visits during endodontics is unclear but it can be left within the tooth for long periods of time when trying to induce apex closure or arrest root resorption.

 Direct  pulp capping, partial  and  complete  pulpotomy  are  important  treatment  options  for  the immature  permanent  tooth.  Whether  the  coronal pulp  tissue  is  preserved in  total,  partially  removed, or removed to the  base of the pulpal floor,  the  preservation of the radicular pulp tissue allows continuing  development and apical  maturation (apexogenesis)  of teeth with open apices. Moreover, in cases of trauma,  in  which tooth development  may  be  interrupted,  induction  of  apexogenesis  should  be  theclinician’s  primary  goal,  with  the  pulp  protection and  encouragement of the remain vitality.

 In  teeth  that  have  suffered trauma,  with  necrotic  pulps and  periapical  pathosis, teeth  are treated to stimulate apical  barrier formation (apexification).  The  time  required  to barrier  formation  can  be  variable,  with  times  from  5  to  20 months. Materials based on Ca(OH)₂  is  suitable  in  pulpotomy  as direct  pulp  capping  treatment; they can  be expected  to provide apical  maturation at comparable time  periods. The  human  pulp  and  surrounding tissue  have  extraordinary regenerative  capacity when a  microbe-free environment  is  provided.

Indications of calcium hydroxide usage include:

a) To promote apical closure in immature teeth.

b) In the management of perforations.

c)  In the treatment of resorption.

d)  As a temporary dressing for canals where filling has to be delayed. In the management of recurrent infections during RCT.

 

Regardless of the sealer selected, all are toxic until they set. For this reason, extrusion of sealers into the periradicular tissues should be avoided.

1.  Zinc oxide-eugenol and resin sealers have a history of successful use over an extended period. Zinc oxide-eugenol sealers have the advantage of being resorbed if extruded into the periradicular tissues. Also this group of materials provides an anti-inflammatory action to the periradicular tissues, because they contain steroid anti-inflammatory medicine in their composition.

2.  Calcium hydroxide sealers were recently introduced for their potential therapeutic benefits. In theory these sealers exhibit an antimicrobial effect and haveosteogenic potential. Unfortunately these actions have not been demonstrated, and the solubility required for release of calcium hydroxide is a distinct disadvantage.

3.   Glass ionomers have been advocated for use in sealing the radicular space because of their dentin bonding properties. A disadvantage is their difficult removal if retreatment is required.

4.  Sealers containing paraformaldehyde (e.g. “FOREDENT”) are contraindicated in endodontic treatment. Although the lead and mercury components have beenremoved from the formulations over time, the paraformaldehyde content has remained constant and toxic. These sealers are not approved by the U. S. Food and Drug Administration. These materials can be used in the case of sclerosed and obliterated root canals, when instrumental treatment can’t be hold; as a result the paste on the basis of paraformaldehyde is applied only at the root canal orifices. In this case the mummifying of the pulp is conducted.

Controversy surrounds removal of the smear layer before obturation. The smear layer is created on the canal walls by manipulation of the files during cleaning and shaping procedures. It is composed of inorganic and organic components that may contain bacteria and their by-products. In theory remnants left on the canal wall may serve as irritants or substrates for bacterial growth or interfere with the development of a seal during obturation. Although fluid movement may occur in obturated canals, bacterial movement does not appear to take place. Recent evidence suggests that removal of the smear layer can enhance penetration of the sealer into the dentinal tubules.

Mummification method. In sclerosed, obliterated, curved root canals, when it is hard to do a proper instrumental endodontic treatment, it is allowed to use pastes that are based on paraformaldehyde for root canal sealing. Depending on clinical situation such pastes are applied either at root canal orifices (sclerosed canal), or the root canal is filled only in the straight part of its (in highly curved canals). Impregnation method envisages usage of AgNO₃ sol. in instrumental not available root canals, for antiseptic treatment (disadvantage- during non-careful handling, tooth crown can be stained in black color).

Removal of the smear layer can be accomplished after cleaning and shaping by irrigation with 17% ethylenediaminetetraacetic acid (EDTA) for 1 minute. Irrigation should be followed with a final rinse of sodium hypochlorite.

Acceptable methods of placing the sealer in the canal include the following:

1. Placing the sealer on the master cone and pumping the cone up and down in the canal

2. Placing the sealer on a file and spinning it counter clockwise

3. Placing the sealer with a lentulo spiral

4. Using a syringe

5. Activating an ultrasonic instrument

The clinician should use care when placing sealer in a canal with an open apex to avoid extrusion.

Solid materials

Silver cones met many of the criteria for filling materials but suffered from several deficiencies. The rigidity that made them easy to introduce into the canal also made them impossible to adapt to the inevitably irregular canal preparation, encouraging leakage. When leakage occurred and the points contacted tissue fluids, they corroded, further increasing leakage.

Semisolid material

Gutta-percha, a semisolid material, is the most widely used and accepted obturating material. Gutta-percha is a natural product that consists of the purified coagulated exudate of mazer wood trees (Isonandra percha) from the Malay archipelago or from South America.

 

 

Gutta-percha does not adhere to the canal walls, regardless of the filling technique applied, resulting in the potential for marked leakage. Therefore, it is generally recommended that gutta-percha (used cold or heated) is used together with a sealer. For an optimal seal the sealer layer should generally be as thin as possible.

Root filling techniques

 

Root canal filling techniques.

Solid core technique

Single cone The single-cone technique consists of matching a cone to the prepared canal. For this technique a type of canal preparation is advocated so that the size of the cone and the shape of the preparation are closely matched. When a gutta-percha cone fits the apical portion of the canal snugly, it is cemented in place with a root canal sealer. Although the technique is simple, it has several disadvantages and cannot be considered as one that seals canals completely. After preparation, root canals are seldom round throughout their length, except possibly for the apical 2 or 3 mm. Therefore, the single-cone technique, at best, only seals this portion.

Cold lateral condensation  

This is a commonly taught method of obturation and is the gold standard by which others are judged. The technique involvesplacement of a master point chosen to fit the apical section of the canal. Obturation of the remainder is achieved by condensation of smaller  accessory points. The steps involvedare:

1.  Select GP master point to correspond with the master apical file instrument. This should fit the  apical region snugly at the working length so that on removal a degree ofresistance or ‘tugback’ is  felt. If there is no tugback select a larger point or cut 1 mm at a time off the tip of the point until a good fit is obtained. The point should be notched atthe correct working length to guide its placement to the apical constriction.

 2 . Take a radiograph to confirm that the point is in correct position if you are in any doubt.

 3.  Coat walls of canal with sealer using a small file.

 4.  Insert the master point, covered in cement.

 5 . Condense the GP laterally with a finger spreader to provide space into which accessory points can be inserted until the canal is full.

 6.  Excess GP is cut off with a hot instrument and the remainder packed vertically into the canal with a cold plugger.

 

 

Softened core techniques

 

Warm lateral condensation As above, but uses a warm spreader after the initial cold lateral condensation. Finger spreaders can be heated in a flame or a specialelectronically heated device (Touch of heat) can be used.

 

Vertical condensation

In this technique  the GP is warmed using a heated instrument and then packed vertically good apical stop is necessary to prevent apical extrusion of the filling, butwith practice a very dense root filling can result. Time consuming.

 

 

 

Coated carriers (e.g. Thermafil) These are cores of metal or plastic coated withGP. They are heated in an oven and then simply pushed into the root canal to thecorrect length. The core is then severed with a bur. A dense filling results, but again apical control is poor and extrusions common.  They are expensive and difficult to remove.

 Once the filling is in place the tooth will need to be permanently restored, provided the followup radiograph is satisfactory. Fillings that appear inadequate radiographicallymay be reviewed regularly, or replaced, depending upon the clinical circumstances.

Endodontic therapy is a sequence of treatment for the pulp of a tooth which results in the elimination of infection and protection of the decontaminated tooth from future microbial invasion. This set of procedures is commonly referred to as a “root canal.” Root canals and their associated pulp chamber are the physical hollows within a tooth that are naturally inhabited by nerve tissue, blood vessels and other cellular entities. Endodontic therapy involves the removal of these structures, the subsequent shaping, cleaning, and decontamination of the hollows with tiny files and irrigating solutions, and the obturation (filling) of the decontaminated canals with an inert filling such as gutta percha and typically a eugenol-based cement. Epoxy resin, which may or may not contain Bisphenol A is employed to bind gutta percha in some root canal procedures. 

After endodontic surgery the tooth will be “dead,” and if an infection is spread at the apex, root end surgery is required.

Although the procedure is relatively painless when done properly, the root canal remains a stereotypically fearsome dental operation.

Root canal procedure: unhealthy or injured tooth, drilling and cleaning, filing with endofile, rubber filling and crown

Root canal treatment

Tooth #13, the upper left second premolar, after excavation of DO decay. There was a carious exposure into the pulp chamber (red oval), and the photo was taken after endodontic access was initiated and the roof of the chamber was removed.

Tooth 5, the upper right first premolar, after extraction. The two single-headed arrows point to the CEJ, which is the line separating the crown(in this case, heavily decayed) and the roots. The double headed arrow (bottom right) shows the extent of the abscess that surrounds the apex of the palatalroot.

In the situation that a tooth is considered so threatened (because of decay, cracking, etc.) that future infection is considered likely or inevitable, a pulpectomy, removal of the pulp tissue, is advisable to prevent such infection. Usually, some inflammation and/or infection is already present within or below the tooth. To cure the infection and save the tooth, the dentist drills into the pulp chamber and removes the infected pulp and then drills the nerve out of the root canal(s) with long needle-shaped drills. After this is done, the dentist fills each of the root canals and the chamber with an inert material and seals up the opening. This procedure is known as root canal therapy. With the removal of nerves and blood supply from the tooth, it is best that the tooth be fitted with a crown.

The standard filling material is gutta-percha, a natural polymer prepared from latex from the percha (Palaquium gutta) tree. The standard endodontic technique involves inserting a gutta-percha cone (a “point”) into the cleaned-out root canal along with cement and a sealer. Another technique uses melted or heat-softened gutta-percha which is then injected or pressed into the root canal passage(s). However, as gutta-percha shrinks as it cools, thermal techniques can be unreliable and sometimes a combination of techniques is used. Gutta-percha is radiopaque, allowing verification afterwards that the root canal passages have been completely filled in, without voids.

An alternative filling material was invented in the early 1950s by Angelo Sargenti. It has undergone several formulations over the years (N2, N2 Universal, RC-2B, RC-2B White), but all contain paraformaldehyde. The paraformaldehyde, when placed into the root canal, forms formaldehyde, which penetrates and sterilizes the passage. The formaldehyde is then theoretically transformed to harmless water and carbon dioxide. The outcome is better than a root canal done with gutta percha according to some investigations. There is however a lack of indisputable, scientifically made studies according to the Swedish Council on Health Technology Assessment.

In rare cases, the paste like any other material can be forced past the root tip into the surrounding bone. If this happens, the formaldehyde will immediately be transformed into a harmless substance. The blood normally contains 2 mg formaldehyde per liter and the body regulates this in seconds. The rest of an overfill will be gradually absorbed and the end result is normally good. In 1991 the ADA Council on Dental Therapeutics resolved that the treatment was “not recommended”, and it is not taught in any American dental school. Scientific evidence in endodontic therapy was, and still is lacking.The Sargenti technique has its advocates, however, who believe N2 to be less expensive and at least as safe as gutta-percha.

For some patients, root canal therapy is one of the most feared dental procedures, perhaps because of a painful abscess that necessitated the root canal procedure. However, dental professionals assert that modern root canal treatment is relatively painless because the pain can be controlled with a local anesthetic during the procedure and pain control medication can be used before and/or after treatment assuming that the dentist takes the time to administer one. However, in some cases it may be very difficult to achieve pain control before performing a root canal. For example, if a patient has anabscessed tooth, with a swollen area or “fluid-filled gum blister” next to the tooth, the pus in the abscess may contain acids that inactivate any anesthetic injected around the tooth. In this case, the dentist may drain the abscess by cutting it to let the pus drain out. Releasing the pus releases pressure built up around the tooth; this pressure causes the pain. The dentist then prescribes a week of antibiotics such as penicillin, which will reduce the infection and pus, making it easier to anesthetize the tooth when the patient returns one week later. The dentist could also open up the tooth and let the pus drain through the tooth, and could leave the tooth open for a few days to help relieve pressure.

At this first visit, the dentist must ensure that the patient is not biting into the tooth, which could also trigger pain. Sometimes the dentist performs preliminary treatment of the tooth by removing all of the infected pulp of the tooth and applying a dressing and temporary filling to the tooth. This is called a pulpectomy. The dentist may also remove just the coronal portion of the dental pulp, which contains 90% of the nerve tissue, and leave intact the pulp in the canals. This procedure, called a “pulpotomy”, tends to essentially eliminate all the pain. A pulpotomy may be a relatively definitive treatment for infectedprimary teeth. The pulpectomy and pulpotomy procedures eliminate almost all pain until the follow-up visit for finishing the root canal. But if the pain returns, it means any of three things: the patient is biting into the tooth, there is still a significant amount of sensitive nerve material left in the tooth, or there is still more pus building up inside and around the infected tooth; all of these cause pain.

After removing as much of the internal pulp as possible, the root canals can be temporarily filled with calcium hydroxide paste. This strong alkaline base is left in for a week or more to disinfect and reduce inflammation in surrounding tissue. Ibuprofen taken orally is commonly used before and/or after these procedures to reduce inflammation. The following substances are used as root canal irrigants during the root canal procedure:

·       5.25% sodium hypochlorite (NaOCl)

·       6% sodium hypochlorite with surface modifiers for better flow into nooks and crannies

·       2% chlorhexidine gluconate (Perioxidina Plus-2)

·       0.2% chlorhexidine gluconate plus 0.2% cetrimide (Cetrexidin)

·       17% ethylenediaminetetraacetic acid (EDTA)

·        Framycetin sulfate (Septomixine)

·        Biopure MTAD Mixture of citric acid, Docycline, and Tween-80 (detergent) by Dentsply USA (MTAD)

After receiving a root canal, the tooth should be protected with a crown that covers the cusps of the tooth. Otherwise, over the years the tooth will almost certainly fracture, since root canals remove tooth structure from the tooth and undermine the tooth’s structural integrity. Also, root canal teeth tend to be more brittle than teeth not treated with a root canal. This is commonly because the blood supply to the tooth, which hydrates and nourishes the tooth structure, is removed during the root canal procedure, leaving the tooth without a source of moisture replenishment. Placement of a crown or cusp-protecting cast gold covering is recommended also because these have the best ability to seal the root canaled tooth. If the tooth is not perfectly sealed, the root canal may leak, causing eventual failure of the root canal. Also, many people believe once a tooth has had a root canal treatment it cannot get decay. This is not true. A tooth with a root canal treatment still has the ability to decay, and without proper home care and an adequate fluoride source the tooth structure can become severely decayed (often without the patient’s knowledge since the nerve has been removed, leaving the tooth without any pain perception). Thus, non-restorable carious destruction is the main reason for extraction of teeth after root canal therapy, with up to two-thirds of these extractions. Therefore it is very important to have regular X-rays taken of the root canal to ensure that the tooth is not having any problems that the patient would not be aware of.

Pulp tissue removed during endodontic therapy by a size 20 broach file.

The procedure is often complicated, depending on circumstances, and may involve multiple visits over a period of weeks. The cost is typically high.

Alternatives

The alternatives to root canal therapy include no treatment, tooth extraction, or 3Mix-MP procedure. Following tooth extraction, a single missing tooth can be replaced with a dental implant, fixed partial denture (commonly known as a bridge), or by a removable partial denture. There are risks to no treatment, such as pain, infection, and the possibility of worsening dental infection such that the tooth will be no longer restorable (root canal treatment will not be successful, often due to excessive loss of tooth structure). If extensive loss of tooth structure occurs, extraction will be the only treatment option.

In December 2010, a study was published demonstrating a new alternative to root canal therapy in treating infected tooth pulps, 3Mix-MP procedure, through the local application of an antibacterial drug mixture.  While previous studies had failed in similar experiments, this study succeeded by utilizing a unique vehicle for the antibiotics, propylene glycol, which has been shown to successfully penetrate and spread through dentinal tubules. This is an important finding which seems to offer an alternative to root canal therapy other than tooth extraction.

Innovation

In the last ten to twenty years, there have been great innovations in the art and science of root canal therapy. Dentists now must be educated on the current concepts in order to optimally perform a root canal. Root canal therapy has become more automated and can be performed faster, thanks to advances in automated mechanical instrumentation of teeth and more advanced root canal filling methods. Most root canal procedures are done in one dental visit, lasting around 1–2 hours. Dentists also possess newer technologies that allow more efficient, scientific measurements to be taken of the dimensions of the root canal that must be filled. Many dentists use dental loupes to perform root canals, and the consensus is that root canals performed using loupes or other forms of magnification are more likely to succeed than those performed without them. Although general dentists are becoming versed in these advanced technologies, they are still more likely to be used by specialist root canal doctors (known as endodontists).

Laser root canal procedures are a controversial innovation. Lasers may be fast but have not been shown to thoroughly disinfect the whole tooth, and may cause damage.

Procedural accidents

Instruments may separate (break) during root canal treatment, meaning a small portion of the metal file used during the procedure is separated inside the tooth. The file segment may be left behind if an acceptable level of cleaning and shaping has already been completed and attempting to remove the segment would risk damage to the tooth. While potentially disconcerting to the patient, having metal inside of a tooth is relatively common, such as with metal posts, amalgam fillings, gold crowns, and porcelain fused to metal crowns. The occurrence of file separation is proportional to the narrowness, curvature, length, calcification and number of roots on the tooth being treated. Complications resulting from incompletely cleaned canals, due to blockage from the separated file, can be addressed with surgical root canal treatment. The occurrence of instrument separation is well documented.

Success and prognosis

Root canal treated teeth may fail to heal, for example if the dentist does not find, clean and fill all of the root canals within a tooth. On a maxillary molar, there is a more than 50% chance that the tooth has four canals instead of just three. But the fourth canal, often called a “mesio-buccal 2”, tends to be very difficult to see and often requires special instruments and magnification in order to see it (most commonly found in first maxillary molars; studies have shown an average of 76% up to 96% of such teeth with the presence of an MB2 canal). This infected canal may cause a continued infection or “flare up” of the tooth. Any tooth may have more canals than expected, and these canals may be missed when the root canal is performed. Sometimes canals may be unusually shaped, making them impossible to clean and fill completely; some infected material may remain in the canal. Sometimes the canal filling does not fully extend to the apex of the tooth, or it does not fill the canal as densely as it should. Sometimes a tooth root may be perforated while the root canal is being treated, making it difficult to fill the tooth. The perforation may be filled with a root repair material, such as one derived from natural cement called MTA. A specialist can often re-treat failing root canals, and these teeth will then heal, often years after the initial root canal procedure.

However, the survival or functionality of the endodontically-treated tooth is often the most important aspect of endodontic treatment outcomes, rather than apical healing alone. Recent studies indicate that substances commonly used to clean the root canal space incompletely sterilize the canal. A properly restored tooth following root canal therapy yields long-term success rates near 97%. In a large scale Delta Dental Study of over 1.6 million patients who had root canal therapy, 97% had retained their teeth 8 years following the procedure, with most untoward events, such as re-treatment, apical surgery or extraction, occurring during the first 3 years after the initial endodontic treatment. Endodontically treated teeth are prone to extraction mainly due to non-restorable carious destruction and to a lesser extent to endodontic-related reasons such as endodontic failure, vertical root fracture, or perforation (procedural error).

Systemic issues

An infected tooth may endanger other parts of the body. People with special vulnerabilities, such as prosthetic joint replacement or mitral valve prolapse, may need to take antibiotics to protect from infection spreading during dental procedures. Both endodontic therapy and tooth extraction can lead to subsequent jaw bone infection. The American Dental Association (ADA) asserts that any risks can be adequately controlled.

In the early 1900s, several researchers theorized that bacteria from teeth which had necrotic pulps or which had received endodontic treatment could cause chronic or local infection in areas distant from the tooth through the transfer of bacteria through the bloodstream. This was called the “focal infection theory”, and it led some dentists to advocate dental extraction. In the 1930s, this theory was discredited, but the theory was recently revived by a book entitled Root Canal Cover-Up Exposed which used the early discredited research, and further complicated by epidemiological studies which found correlations between periodontal disease and heart disease, strokes, and preterm births. Bacteremia (bacteria in the bloodstream) can be caused by dental procedures, particularly after dental extractions, but endodontically treated teeth alone do not cause bacteremia or systemic disease.

Root canals are a part of dentistry called endodontics, which is concerned with the pathology of dental pulp and the area surrounding the root. A root canal is a procedure to allow a tooth that is painful or no longer viable because of nerve damage or death to remain in the mouth. Most dentists consider root canals an advance in dentistry–superior alternative to removal of a seriously compromised tooth. However a growing number of physicians, including dentists, believe that root canals can be the cause of, or at least contribute to, a long list of illnesses and degenerative diseases.

A “root canal” allows a patient to keep a dead tooth in his or her mouth. The fallacy with this concept is that the body doesn’t like dead things in it and will try, sometimes desperately, to get rid of the dead thing. Notwithstanding, the fact that it may be “handy” to save a tooth for “dental convenience”, it does not change the fact that root canal treatments can devastate the human immune system.Twenty million root canals are performed in the U.S. annually, and this number is estimated to double within the next few years.

There are many presumptions about root canal therapy which are based in myth rather than science. The philosophy underlying the teaching of dentistry limits its practice to mechanics, pain control and aesthetics. The systemic effects of dental treatment are rarely considered.Conventional root canals have been controversial since the turn of the century, when formaldehyde was used to treat the nerve which inevitably killed it, and the bone around the tooth, as well. This treatment is still used by 20% of American dentists and is called the Sargenti method, but it is denounced by the ADA because it contains formaldehyde compounds and lead. The current formulas are said to have removed the lead, but tens of millions of root-canal treatments using the old formulas are still in people’s mouths. While the normal dental profession has been striving to improve the technique, much research has shown that even modern root canals pose health hazards to the body. This is due to the delitirious effects of residual infections; from the seepage of toxic substances still used in the process; and from the interference of the flow of bioelectrical energy through acupuncture meridians associated with all the organs of the body.

All conventional root canals still employ toxic substances to sterilize the interior of the tooth, such as eugenol (oil of clove) and formocresol(formaldehyde-creosote). Most dentists also use gutta-percha to fill the canal.

The toxicity of root canals was disclosed by Mayo’s Clinic and Dr. Weston Price jointly back in about 1910. Close to a century ago. Weston Price’s textbook on root canals, published in 1922, upset the dental associations at that time, and still does today. The American Dental Association (ADA), denies his findings and claims that they have proven root canals to be safe; however, no published data from the ADA is available to confirm this statement. Statements, but no actual research.

Dr. Hal Huggins attention was drawn to the increase in autoimmune disease after the high-copper amalgams of 1975 were initiated as “state of the art” fillings, which the ADA claimed released no mercury. On the contrary, studies from Europe found that the high-copper amalgams released fifty times more mercury than previous amalgam! In watching these changes regarding the onset of autoimmune disease, he noticed a blip in the statistics—an increase in amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease) in 1976. The actual number of cases of multiple sclerosis increased tremendously, from an average of 8800 per year during the period 1970 to 1975, to an increase of up to 123,000 in one year. That year being 1976, the birth date of high-copper amalgams.

 Objectives of Root canal preparation

·       Remove remaining pulp tissue

·       Eliminate microorganism

·       Remove debris

·       Shape the root canal

·       So that root canal system can be cleaned and filled

 

Requirements of Root canal preparation

·       Prepared canal should include the original canal

·       Apical constriction should be maintained

·       Canal should end in an apical narrowing

·       Canal should be tapered from crown to apex

·       Preparation should be undertaken with copious irrigation

·       The final length of the preparation should not be reduce by treatment

Root canal preparation techniques
Apical to coronal	Coronal to  apical
1.Standardized technique 2. Step back technique 3. Balanced forces technique Apical to coronal	1 Step down technique 2.Double flared technique 3. Crown down pressure less technique Coronal to  apical

 

·       Can be use for straight tiny canal

·       Unsuitable for curve canals

·       Common problems

§  Ledging

§  Zipping

§  Elbow formation

§  Perforation

§  Loss of working length

 

·       Overcomes procedural errors of ST

·       Suitable for Slight to moderate curve canals

·       Not suitable for severely curve canals

·       Can be improve by

§  Specific filing technique

§  Non-cutting tip

§  Flexible files

 Note an increase in 1976 and another increase in slope in 1991. In 1990, the dental association “suggested” that dentists perform thirty million root canals per year by the year 2000. Dentists accomplished that goal by 1999. The bar has now been raised to sixty million per year. The unexplained increase in MS (8800 to 123,000) coincided with the advent of high copper amalgams. The increase in ALS in the same year is suggestive of the same cause. ALS also increased in 1991 as more root canals were performed. Statistical coincidence?

 

There are bacteria in root canals that favor destruction of the nervous system and many other systems, resulting in the creation of autoimmune reactions. The common denominator is the formation of a hapten. A hapten is a small molecule that can elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself. In general, only large molecules, infectious agents, or insoluble foreign matter can elicit an immune response in the body.

 Healthy cells have a code imprinted on them. It is called the Major Histo-compatibility Complex (MHC). This is your personal code called “self.” Your body considers other code or alteration of this code to be “non-self.” The immune system is trained to kill and eliminate any “non-self” invaders. If an atom of mercury attaches to a normal healthy cell, a hapten is formed and the immune system immediately identifies that cell as “nonself.” The immune system then proceeds to kill the contaminated cell. If mercury attaches to a nerve cell, the result is a neurological disease, such as multiple sclerosis, Lou Gehrig’s disease, seizures or lupus. If mercury attaches to a binding site on a hormone, that endocrine function is altered. Mercury can attach to almost any cell in the body and create autoimmune diseases in those tissues.

 Lately, it has become evident that toxins from anaerobic bacteria have the same ability to create non-self autoimmune diseases by interfering with the MHC. This is the project that Dr. Price began to study a century ago. Resistance from organized dentistry was the same then as it is today. Price wondered why dentistry was considered a “health” profession. Price was concerned about the pathological bacteria found iearly all root canal teeth of that time. He was able to transfer diseases harbored by humans from their extracted root canal teeth into rabbits by inserting a fragment of a root canal root under the skin in the belly area of a test rabbit. He found that root canal fragments from a person who had suffered a heart attack, when implanted into a rabbit, would cause a heart attack in the rabbit within a few weeks. Transference of heart disease could be accomplished 100 percent of the time. Some diseases transferred only 88 percent of the time, but the handwriting was on the wall.

 Dr. Price discovered that root canals have within them bacteria capable of producing many diseases. They have no place in the body. Which is more important? The life of the tooth or the life of the patient? This is still the primary argument facing us today.

 ROOT CANALS AND NEUROLOGICAL DISEASE

Considering the difficulty of culturing anaerobic bacteria, it was hard to identify them with 1920s technology. Most of the bacteria reported by organized dentistry at that time were aerobes of unknown significance. Today, with DNA analysis available, anaerobic bacteria (the dangerous kind) can be identified whether dead or alive by the presence of their tell tale DNA signatures.

 The goal of dentistry is to save teeth. Root canals allow dentists to maintain many teeth for years instead of extracting them. But is this goal appropriate considering the biological expense exposed with DNA research? What is more important? To save the life of the tooth or that of the patient?

 HAVENS FOR BACTERIA

Dr. Price, while head of research for the nowdefunct National Dental Association, took one thousand extracted teeth and reamed them out as dentists normally do, prior to filling the canals with wax. Price sterilized the canals with forty different chemicals far too toxic to be used in a live human situation; he wanted to see whether the canals could be permanently sterilized. After forty-eight hours, each tooth was broken apart, and cultured for the presence of bacteria. Nine hundred ninety out of one thousand cultured toxic bacteria just two days after treatment with chemicals designed to make the tooth sterile. Where did these bacteria come from?

 An overview of the structure of a tooth shows the outer layer, known as enamel, the second layer, known as dentin, and the inner portion, known as the pulp chamber, where the nerve lives. On the outside of the tooth is what is called the periodontal ligament. Teeth are not attached directly to bone. Fibers come out of the tooth and intertwine with fibers coming out of the bone, and they unite to form what is called the periodontal ligament.

The second layer of the tooth, the dentin, is not really solid but composed of tiny dentinal tubules. In a front tooth, if all these tubules were attached end to end, they would reach over three miles. The tubules have adequate space to house many thousands of bacteria. This is where the bacteria were hiding in the thousand teeth Price tested. From the dentin tubules, bacteria can migrate either into the pulp chamber, where space is left as the gutta percha—a natural form of rubber used to fill the space inside the cleaned-out root—shrinks upon cooling, rebounding from the force applied to push the wax down the canal, and losing the liquid portion, or

A tooth has one to four major canals. This fact is taught in dental school, but never mentioned are the additional “accessory canals.” Price identified as many as seventy-five separate accessory canals in a single central incisor (the front tooth). There is no way that any dental procedure can reach into these accessory canals and clean out the dead tissue. This necrotic tissue creates a home for multiple bacterial infections outside the tooth in the periodontal ligament. With added food supply from this area, the anaerobic bacteria can multiply and their toxins can contribute to the onset of disease.

 The root apex (terminal end) is the primary area of concentration of infection. Even though this may be the last area to show infection, dentistry generally considers a tooth sterile unless areas of bone resorption show up on X-ray. Upon cooling and shrinking of the gutta percha, space is left at the apex in which bacteria can thrive, where neither white blood cells of the immune system, nor antibiotics can reach them.

 TOXIC MICROORGANISMS

Hal Huggins’ first DNA studies examined bacteria retrieved from crushed root tips. Science can identify eighty-three different anaerobic bacterial species with DNA testing. Root canals contain fifty three different species out of these eighty-three samples. Some are more dangerous than others, and some occur frequently, some occasionally. Selecting those that occur more than 5 percent of the time, he found:

·       Capnocytophaga ochracea 

·       Fusobacterium nucleatum 

·       Gemella morbillorum

·       Leptotrichia buccalis 

·       Porphyromonas gingivalis

 Four affect the heart, three the nerves, two the kidneys, two the brain and one the sinus cavities. Let’s look at five major bacterial species lurking in root canals more closely, keeping in mind that these are only five of the fifty-three that are routinely found in root canal teeth.

Capnocytophaga ochracea: Found in brain abscesses associated with dental source of infection. Causes human disease in the central nervous system. Also related to septicemia and meningitis.

Fusobacterium nucleatum: Produces toxins that inhibit fibroblast cell division and wound healing processes. Causes infection in the heart, joints, liver and spleen.

Gemella morbillorum: Linked to acute invasive endocarditis, septic arthritis and meningitis.

Leptotrichia buccalis: Reduces the number of neutrophils (a critically important white blood cell), thus lowering immune competence.

Porphyromonas gingivalis: Destroys red blood cells by drilling holes (porins) in them, causing the cell to “bleed to death.” Low red cell counts that do not recover after dental revision are frequently responding to the porin activity of this microbe. P. gingivalis also alters the integrity of the endothelial lining of blood vessels, which leads to inflammation and bleeding in the inner lining of blood vessels. This is the key step in formation of atherogenesis that leads to heart attacks. P. gingivalis can change friendly bacteria into pathogens.

 Shouldn’t we question the wisdom of supplying a haven for these microbes so close to our brain and circulatory system? Does this information validate the claims of “sterile” root canals? Dentists claim they can “sterilize” the tooth before forcing the gutta percha wax down into the canal. Perhaps they can sterilize a column of air in the center of the tooth, but is that really where the problem is? Bacteria wandering out of the dentinal tubules is what Price was finding, and what we were finding in the crushed tooth samples. But the problem doesn’t end there.

 Huggins tested blood samples adjacent to the removed teeth and analyzed them for the presence of anaerobic bacteria. Approximately 400 percent more bacteria were found in the blood surrounding the root canal tooth than were in the tooth itself. It seems that the tooth is the incubator. The periodontal ligament supplies more food, therefore higher concentration of bacteria. But the highest pathological growth was in the bone surrounding the dead tooth. Looking at bacterial needs, there is a smorgasbord of bacterial nutrients present in the bone. This explains the tremendous increase in bacterial concentration in the blood surrounding the root canal tooth. Try sterilizing that volume of bone.

 Just the presence of dead tissue will cause the immune system to launch an attack. Infection, plus the autoimmune rejection reaction, causes more bacteria to collect around the dead tissue. Every time a person with a root canal bites down, these bacteria are flushed into the blood stream, and they start looking for a new home. Chemotaxis, or the chemical attraction of a specific bacteria for a specific tissue, assists the anaerobes in finding new quarters in the heart, nervous system, kidney, brain, etc., where they will perform their primary damage.

 Many of the bacteria in the surrounding bone are present in far more than 50 percent of the samples tested. Streptococcus mutans was found in 92 percent of the blood samples. It can cause pneumonia, sinusitis, otitis media, meningitis and tooth decay. 

Streptococcus mitis was found 92 percent of the time. This microbe attacks the heart and red blood cells. It is a hearty bacteria, for it went to the moon (hiding in a camera) on an unmanned expedition, stayed there over two years in an environment without atmosphere, exposed to temperatures of 250 degrees Fahrenheit during the day, minus 250 in the shadow. Upon returning to Earth with the astronauts of Apollo 12, over two years later, this microbe was still alive. In humans, S. mitis binds to platelets and is involved in the pathogenesis of infective endocarditis. You don’t want this guy living in your dead root canal tooth.

 Of the top eight bacteria in the blood adjacent to root canal teeth, five affect the heart, five the nervous system, two the kidney, two the liver, and one attacks the brain sinus, where they kill red blood cells. Of these, Prevotella intermedia (present in 76 percent of the samples) attacks heart, kidney and sinus; Strep intermedius (present in 69 percent of the samples) attacks heart, nerves, lungs, liver and brain.

 DNA examination of extracted root canals has shown bacterial contamination in 100 percent of the samples tested. This is quite the opposite of official claims that root canals are 97 percent successful. They need a new definition of success.

 

CAVITATIONS

Cavitations are the next big problem that result from dental procedures. Cavitations are areas of unhealed bone left over after a tooth extraction. Dentists are generally taught to remove a tooth and leave the periodontal ligament in the socket, a procedure which would be like delivering a baby and leaving the placenta in the uterus. These socket areas with the ligament left in place rarely heal. After tooth removal, a cap of about 2 millimeters (one sixteenth of an inch) covers the extraction site, leaving a hole the size of the root of the tooth behind. In records of five thousand surgical debridements (cleaning) of cavitations, only two were found to be healed. When the periodontal ligament is left in the bone, the body senses that the tooth is still there, and the order for healing is canceled. These holes are lined with many of the same bacteria found in root canal sockets, but actually more different species. Whereas root canal teeth contain up to fifty-three different species of bacteria, cavitations yield up to eighty-two of the eighty-three test for.

 Of the five most frequently present bacteria found in cavitations, three affect the heart, two the nervous system and one the kidneys and lungs. They are as follows:

Streptococcus mutans (occurrence 63 percent of the samples), affects the nervous system, can cause pneumonia, sinusitis, otitis media and meningitis. It has also been blamed for causing dental decay in teeth, but this may be more the result of the fluid flow pulling bacteria into the tooth than actual active invasion by the bacteria.

Porphyromonas gingivalis (occurring in 51 percent of the samples), damages the kidney, alters integrity of endothelial lining of blood vessels, and induces foam cells from macrophages, contributing to atherogenesis. It contains proteases that lyse red blood cells and extract nutrients (primarily iron) from the red blood cells. This action is called porin forming, which can destroy red blood cells rapidly. (By the way, P. gingivaliscan both up and down regulate about five hundred different proteins critical to maintaining our normal biochemical actions.)

Candida albicans (present in 44 percent of the samples), in its yeast form is beneficial in the process of demethylation of methyl-mercury as well as its ability to destroy pathogenic bacteria in the intestinal tract. When converted into the fungal form by a shift in pH in the digestive system, candida can penetrate the intestinal wall, leaving microscopic holes that allow toxins, undigested food particles, bacteria and other yeasts to enter the blood stream. This condition is sometimes referred to as Leaky Gut Syndrome, which can lead to environmental intolerances.

Prevotella intermedia (occurrence rate of 44 percent) has as its primary concern coronary heart disease (CHD). P. intermedia invades human coronary artery endothelial cells and smooth muscle cells. It is generally located in atheromatous plaques. Cellular invasion of cardiac muscle is central to the infective process.

 ANTIBIOTICS

Antibiotics cannot be used in infections of this nature. Most antibiotics are “bactericidal”—think suicidal, or homicidal. When bactericidal antibiotics kill a bacterium, the bacterium explodes. The fragments are not eliminated immediately, for each piece is a lipopolysaccharide calledendotoxin. By way of contrast, exotoxins are the toxic chemicals that are released by pathogenic bacteria, and endotoxins are toxic entities (fragments of the original bacteria) that are the result of the bacterial explosion caused by the antibiotic. Endotoxins present a huge challenge to the immune system, for now, instead of facing one bacterium, it has to process and eliminate perhaps one hundred endotoxins. With dozens of bacteria to confront from each single root canal or cavitation, no one antibiotic can kill all of them, and if there were one, the resulting dead bacterial corpses would overwhelm the body and produce either greater disease or death.

 

Broad spectrum antibiotics cannot be used for this reason. Sometimes even one capsule of antibiotic produces more problems than the immune system can tolerate. Plus, it takes only two or three capsules to completely sterilize the gut of its four or more pounds of friendly bacteria. Antibiotics are far more powerful and potentially devastating than anyone ever thought they were. Antibiotics should be used with ultra caution,not routinely given for ten days or so after oral surgery, “just in case.”

 There are other ways to get these microbes under control, and several are being tested at this time. It is advantageous to have intravenous vitamin C and occasionally a non-killing antibiotic is added to this solution. This combination does reduce the challenge to the immune system, but, overall, root canals represent a rock-and-hard place situation.

 Leave the root canal or cavitation in the body, and there is the potential of creating an unwanted autoimmune or degenerative disease that could be life threatening. Toxins and bacteria can both leak from these contamination sites wreaking havoc with a person’s cardiovascular, endocrine, nervous and immune systems. The public needs to be informed, so they can make educated choices in the trade-off between toxic convenience and health.

 Removing the offending tooth presents problems that must be confronted, or other problems can be induced—problems not as dangerous as the continuous bacterial spill, but ones that need to be avoided if possible. In order to allow the immune system to focus on healing, all other offending dental materials should be removed (mercury, copper, implants, tattoos and nickel crowns) so that the immune system can deal with the bacterial challenge instead of the bacteria plus toxic metals. Nutrition should be calculated from the aspect of the blood chemistries commensurate with one’s ancestral diet and in line with the dietary principles formulated by Dr. Price. Recovery from a root canal is complicated, but your life is worth salvaging.

 

These studies in DNA analysis of bacteria in root canals and cavitations confirm the fact that Dr. Weston Price, despite being one century ahead of his colleagues, was absolutely correct in determining that bacteria-laden root canals have no place in the body of people interested in their health. This toxic waste spill can be stopped, but not with the assistance of dental associations, which continue to insist that the procedure of root canals is perfectly safe. The recent increase in suggested quota up to sixty million root canals per year is not in the best interest of their patients, nor can that action do anything but increase health costs for the innocent patient.

 Root canals are not worth the price.

 In the 1950s. Reinhold Voll, a German M.D., using an electro-acupuncture biofeedback system he had developed, discovered that each tooth in the mouth relates to a specific acupuncture meridian. He found that if a tooth became infected or diseased, the organ on the same meridian would also become unhealthy. Conversely, he found that a diseased organ could cause a problem with its corresponding tooth.

When you have a root canal, or even a big filling, or crown or anything that is not compatible with the body, it sets up an interference field,blocking or altering the energy meridian passing through it. It will affect different parts along that meridian, different organ systems in the body. And usually will cause it to have a problem as well.

If the tooth is removed, the energy does tend to pass through it. However, without the tooth in the bone, it is still altered. Without stimulation from a tooth, blood circulation and lymphatic drainage will be impaired, and the bone and tissue surrounding the extraction site can become diseased and die. Infections in the teeth, and toxins, have no place to go but down; down into the jaw bone and into the rest of the body, creating systemic pathologies.

 Of equal interest is the relationship of root filled teeth to traditional Chinese medicine and body energies. All teeth are linked to the body via acupuncture meridians and having a root filled tooth, a large amalgam filling, a crown, or anything that is not compatible with the body, on a meridian may set up an interference field, blocking or altering the energy flow ( the chi ‘) passing through this meridian and cause a disease in an organ or body function remote from the tooth. For example a front upper incisor is on the Kidney/ Bladder meridians and having a root treated tooth here may cause gynecological problems, kidney problems, impotence, and sterility if you follow a Chinese medicine theme. These teeth also relate to spinal segments and joints, the front incisor relates to the coccyx and posterior knee and to L2, 3, S 3, and 6.

If the tooth is removed, the energy does tend to pass through it; however, without the tooth in the bone, it is still altered. Without stimulation from a tooth, blood circulation and lymphatic drainage will be impaired, and the bone and tissue surrounding the extraction site can become diseased (cavitations) and die. Infections in the teeth and toxins have no place to go but down; down into the jawbone and into the rest of the body, creating systemic pathologies. Some dentists are trained to look for these areas on X-rays and Cavitat procedures and when these areas are treated they can also bring considerable improvements in patients health. This energetic relationship between teeth and the rest of the body is opening whole new avenues of dental care and the chance for dentists to work with other complementary health workers.

It is assumed in dentistry that the extent of bone loss is a direct indication of the amount of infection present. This is a false assumption because the bone loss may take time to develop. The extent of the bone loss about the end of the root is also a function of the body’s immune system being able to isolate the infection process. It has little to do with the degree of infection. Sometimes there is no bone loss, but instead, a condensation of bone about the end of a dead tooth. Dentists are taught that this indicates a lack of infection. The reality is that teeth showing aCondensing Osteitis are demonstrating that the body’s immune system is incapable of quarantining the infection locally. These are often the teeth which cause the greatest systemic effects.

The toxins generated by the root canal can combine with the mercury leaching from the amalgams and create new chemicals of a much higher toxicity. Some combinations can be more potent than Clostridiumbotulinum (responsible for botulism). Any time you bite down, you are potentially squirting a few molecules of dental poisons into the bloodstream-and often it only takes a few molecules to create a serious problem.

 “Root canals” cause:

Suppression of the immune system

The creation of an “interference field” on the meridian that the particular tooth is on (meridian – a channel of energy that flows between different tissues, organs and structures).

The production of the most toxic organic substance known to man.

Root-canal fillings can cause serious side effects. Dr. Weston price is recognized as the greatest researcher that the dental profession has ever produced. Dr. Price, after observing many patients with crippling degenerative diseases not responding to treatment, suspected infected root canal-filled teeth to be the cause. He then embarked on a 25-year-long study to see if his suspicions were correct. This study was done during the first 3 decades of the 20th century! However this information was not shared with us when we were dental students so we had a big void in our dental education where root canals are concerned.

The Procedure

After numbing the tooth, a hole is then drilled in the top of the tooth, just as if a filling were being placed. The hole is deepened until the internal canal (pulp chamber), containing the nerve, blood and lymph vessels, is reached. Then, little tiny files are used to remove the contents of the chamber (live, dead, or dying pieces of nerves and blood vessels). The dentist now has access to the whole length of the root-canal. Front teeth are supposed to have one, but may have an additional one splitting off of the main canal about one-third of the way up from the apex. These will not show up on X-ray. Multi-rooted teeth, such as some bicuspids and most molars, have two or three roots. Each root has a primarycanal and may have a secondary one as well. Lower molars frequently have two canals in one root that sort of blend into each other, forming what is called a ribbon canal. Curved canals present a problem, as the files used to cut out infected dentin are straight.

Sometimes a file will penetrate the tooth at the curve, and cut its way out of the tooth, missing the curve entirely. Toward the bottom 10 millimeters of the tooth, accessory canals may exit the tooth. Removing the dead tissue and bacteria from each of the canals presents the problem of not being able to see whether all the contents are removed. It’s a dark tiny hole, down a long skinny root, and bacteria and debris are smaller. Knowing when to stop at the apex is another trick. X-ray films are shadows, and show an approximation of how long the root is, but they don’t provide detail about the end of the root. Filling the canal to the x-ray end would actually overfill the canal. Overfilling is a condition most often apt to create infection, thus the presence of unwanted bacteria.

 The now empty canal is widened. Next, a series of treatments is begun which clean and shape the root-canal, which kills the tooth. It is then flushed, treated with chemicals to kill bacteria, and eventually filled with one of a variety of materials, the most popular (93% in U.S.), is a substance called gutta-percha. Gutta-percha is a rubbery, wax petroleum-based, latex material, to which some people are allergic. First, the wax is mixed with chloroform to make it soft. Since gutta-percha does not show up on x-rays, heavy metals, including mercury and lead, are added, to make it radiopaque–sometimes up to 20% of its content. Other chemicals it may contain include formocreasol or para­chlorophenol. These substances can cause inflammation and infection, allergic reactions, and compromise the immune system.

 Eugenol-based cements are used to cement the gutta percha cones into the enlarged canals. Eugenol has an acid pH, whereas the living tissues that surround the root have an alkaline pH. To kill the bacteria, caustic solutions are flushed into them, but the surface tension of the solutions is too high to allow it into the narrow dentin tubules. Sodium hypochlorite (Clorox) and hydrogen peroxide mixtures are used to “sterilize” the inside of the main canals. Sodium hypochlorite and hydrogen peroxide both will injure tissue. These cause inflammation and infection, allergic reactions, and compromised immunity.

 Dr. Weston Price found that teeth retain their sterility at best for only about two days. Most lost sterility within less than twenty four hours.Studies on thousands of teeth have demonstrated the presence of bacteria in 80% to 90% of the canals after they have been “sterilized.“ The primary bacteria found in root canals by Dr. Price included streptococcus, staphylococcus, and spirochetes. He found 90% of the bacteria in the teeth that produced the patients’ acute diseases were streptococcus and 65.5% of the time they belonged to the fecalis family. Bacteriologists today have confirmed that Price’s discoveries were accurate.

Once the root-canal treatment is completed, the top of the tooth in which the hole was drilled is restored with either a filling or crown, depending upon the amount of tooth that remains. A patient is routinely told that a crown will be needed for strength because root-canal treated teeth become brittle and weak because of the inside, including the blood vessels and nerves, having been drilled out to do the treatment. It is quite possible that there will be little of the original tooth left above the gum line and that which is left will be weak. In many cases, a post is placed into the root-canal itself to hold the crown.

Compatibility

Conventional dental procedures do not take into account biocompatibility of the filling materials, potential injury to surrounding tissues due to the caustic nature of substances used and a high percentage of residual bacterial contamination. According to research by Dr. Boyd Haley of the University of Kentucky, at least 75% of root canal teeth have residual bacterial infections remaining in the dentinal tubules, of which there are 3-5 miles in length in each tooth. There is no drug, homeopathic remedy, vitamin or mineral that can effectively kill these tiny bacteria that live in the small tubules in the tooth. Only the use of bio-frequencies (Rife technology) has the capability of pentrating the surrounding bone and root without any damage to tissues. Even then, there is no way to stop new bacteria from entering these tubules from the oral cavity again.These lingering infections produce the most toxic substances known to biochemistry and toxicology, that enter the blood stream and can affect any part of the body.

A dentist, Weston A. Price, brought this information to light in the 1940s. Unfortunately for patients and the dental profession, his scientific documentation and views were pushed aside. To date there is no acceptable conventional therapy to resolve this issue.

Focal Site of Infection

A tooth is an organ, just as any other organ or bone in the body. An abscessed or gangrenous tooth is not only a dead tooth, it is a dead organ. The problem arises because these teeth are dead and prone to infection can threaten to infect surrounding tissue, including the jawbone, possibly triggering cavitations.

 

Today we know that the toxins made by the bacteria that live by the billions in root-canal teeth contain the most toxic organic substance known to man—thio-ethers. Thio-ethers are 1000 times more toxic than botulism toxin, which used to be considered the most toxic organic substance.

So, from a practical standpoint, one would be well-advised to worry less about anthrax and smallpox, and instead, focus on root canals which are much more likely to cause you personal harm. In addition to thio-ethers, other severe toxins from these root-canal bacteria include thio-ethanols and mercaptans which have been found in the tumors of women who have breast cancer, draining through the lymphatic system down the cervical chain of lymph nodes and ultimately in to the breast tissue. Besides being harbored in root canals, these dangerous bacteria also take up residence in cavitations which result from most extracted teeth. Thus one can get a “double-whammy” from the root canals and the cavitations.

Dr. Weston Price

Based on a 25 year extensive study by respected researcher, Dr. Weston Price, scientific data suggests that root canal therapy is the cause of many systemic diseases and illnesses.Dr. Price devised a testing method which disclosed the presence of infection in a tooth which otherwise seemed to be healthy–that is, the implanting of the root canal filled tooth under the skin of a laboratory animal. He found that when the root-filled tooth of a patient with a degenerative disease was extracted and imbedded in an animal, that animal would develop the patient’s disease. He did this in over 5000 animal studies and the results were consistent. In the beginning, Dr. Price did not know just where the infection was hiding in the tooth, only that a patient’s illness was rapidly transferred from his root-filled tooth to laboratory animals in case after case.

Dr. Price was able to culture the bacteria in root-filled teeth and trap their toxins, reproducing a disease in a rabbit by implanting the extracted root-filled teeth and injecting the cultured material into the animal. Dr. Price discovered a wide variety of degenerative diseases to be transferable to rabbits.This involved diseases or conditions such as endocarditis and other heart diseases, kidney and bladder diseases, arthritis, rheumatism, mental diseases, lung problems, stomach ulcers, ovarian diseases, phlebitis, osteomyelitis, and pregnancy complications. Those infections proved so devastating that most animals died with 3-12 days. When these same teeth were sterilized with steam heat and embedded in animals, no adverse health effects were experienced. Furthermore, a large percentage of people recovered from their illnesses after extraction of the root canal filled teeth used in the experiments. When sound, uninfected natural teeth were implanted in animals, no adverse health effects were experienced. This vitally important research was forced underground, and has remained virtually unknown since its 1923 publication.

Although root canal therapy is usually successful in eliminating pain and swelling associated with dead teeth, and in allowing those dead teeth to remain in the mouth to function, the side effects can be hazardous to overall health. It is estimated that only about 30% of the population has a healthy enough immune system to ward off the side effects. The problem is that root canal therapy cannot sterilize the inside of the tooth. As a result, the trapped bacteria mutate and migrate to infect the heart, kidneys, eyes, stomach, and countless other body tissues. This theory, called the focal infection theory, states that a person can have an infection someplace and that the bacteria involved can be transferred by way of the bloodstream to another gland or tissue and therein start a whole new infection. Modern experiences also support this theory. Dr. Issels, a German physician, recommends extraction of root canal teeth as part of his protocol for terminal cancer patients.

Over the last 40 years with 16,000 patients, he has observed a 24% total remission rate. Some transplant surgeons require root canal filled teeth be extracted before performing transplant surgery, because of the risk of focal infection to the new organ from the teeth. If a person has chronic health problems, existing root canal filled teeth or dead teeth should be suspected as a possible cause or influence. Estimates for 1996 ran as high as thirty-five million recipients of root canal therapy; however, most cannot describe the procedure beyond the basics. Root canal or endodontic therapy is performed primarily because of bacterial infection. Frequently pain is the motivating factor. Bacteria infiltrating through the dentin tubules under decay can set up housekeeping in the pulp chamber. This is an ideal environment, being warm, with a constant supply of nutrients, and a waste removal system. Bacteria can wiggle into the dentin tubules (miles-long passageways that traverse the dentin of each tooth) and multiply in accordance with the available oxygen supply.

 Since there are varying degrees of oxygen deprivation, each level of oxygen stimulates the bacteria to mutate into a slightly different bacterium; a whole plethora of critters can develop from just one bacterium. Over 150 different bacterial strains have been identified at the apex or within the pulp chamber of dead or dying teeth. All but five are classified as anaerobic, or those that thrive in the absence of oxygen. These bacteria produce toxic waste products. The toxins can either be picked up by the drainage system at the apex of the tooth, or flow down the dentin tubules into theperiodontal ligament. At the ligament, they can slip into the fluids around the tooth and flow into the bloodstream. They may also be forced up the ligament space into the mouth when the person bites down or chews. Regardless of which direction the toxins go, they will be introduced to the innermost parts of the body.

 The root canal treated tooth is a tooth that is typically still being used iormal chewing. While much of the nerve and blood supply has been removed or damaged by the procedure itself, the tooth still has its original attachment to the jawbone. The high pressures generated in chewing can be expected to physically push toxins out of the socket where they can eventually be picked up by the blood circulation.

 

Dentinal Tubules

A tooth is basically comprised of 3 layers. The enamel (what we see when we look at another person’s teeth, the hard, white attractive outer layer of the tooth), the pulp (a tiny island of soft tissue at the center of the tooth – the same place in a tooth that a core would be in an apple – the so-called “nerve”), and the dentin. Dentin accounts for about 90% of the tooth. When looked at under a microscope, dentin has a very specific structure. It is made up of “millions” of incredibly tiny tubules that radiate outward from the pulp to the outer edge of the tooth.

 If one could some how take each of one of these “millions” of tubules in a front tooth and lay them end to end, they would stretch for 3 miles. Although microscopic in size, these tubules are adequate to house billions of bacteria and even yeast and fungi. The tubules are wide enough to occomodate eight streptococci abreast. These dentinal tubules are like tiny pipes that radiate outward from the pulp to the outer surface of the tooth–kind of like spokes of a wheel (if you think of a cross-section of a tooth). The centers of these tubules are filled with living protoplasm. The protoplasm in these tubules has no blood supply so it depends on the blood vessels in the pulp for it’s nourishment or sustenance.

 Dentin tubules within the root of the tooth can harbor millions of bacteria. These tubules extend from the pulp chamber to the outer bounds of the tooth called the cementum. The periodontal ligament and the apex of the tooth still contain bacteria from the original infection. It is impossible to sterilize the tubules, the ligament, or the apex. Since 93% of root canal treated teeth in the U.S. are filled with gutta percha, and the purpose of filling the canal is to seal the canal from access by bacteria, several basic principles must be ignored to pronounce the canal “sealed.” First, the wax is mixed with chloroform to make it soft. The chloroform evaporates, creating 6.6% space that was occupied by the chloroform. Instruments used to condense the gutta percha are heated in order to soften the wax. When heated wax cools, it shrinks–up to 30% in the first week after placement. This allows a half-micron-sized bacterium to easily make it through the apex, up the root, and into the dentin tubules.

 The relatively huge white blood cells cannot get into a dentin tubule. Antibiotics can’t gain access either. And the periodontal ligament access is difficult if not impossible. Debris from filling the canal spills out the end of the root, forming a good culture medium for bacteria, while providing a barrier for entrance into the canal. Anaerobic bacteria (those living without oxygen), can inhibit phagocytosis of the white blood cells. Root canal bacterial waste products are the real problem. No white blood cell or antibiotic can destroy the chemicals that are produced by bacteria around the root canal treated tooth.

These chemicals kill the most important enzymes in our bodies at lower concentrations than the most toxic of known organic poisons. Disease can result when these are present at little more than the molecular level of concentration. Mercury at 1 to 5 micromolar concentrations will totally abolish the activity of tubulin without any noticeable effect on other brain proteins. Even one-half part per billion can destroy the most resistant enzymes. Inactivating these essential enzymes can lead to many hormonal neurological, autoimmune, and emotional diseases.

In the presence of these root canal poisons, tubulin and creatine kinase, two critical proteins involved in brain function, are inactivated within a few minutes. In a healthy person, the immune system will form pus, soreness, tenderness, and pain–to tell us dead teeth do not belong there. The dentist, anxious to protect his investment in the root canal, will usually prescribe broad-spectrum antibiotics in an effort to calm the situation. Antibiotics will eventually halt the inflammatory process around the root canal tooth, and the pain will subside, but there is no repair.

 

The doctor and patient are now lulled into the illusion that the root canal is successful, but the body undergoes further protective activities; if it cannot loosen up the tooth and exfoliate it, the body builds a wall around it and set up a quarantine, a dense layer of calcium, called condensing osteitis is laid down around the root, giving the x-ray appearance of healed bone. The bacteria cannot invade the body, nor can the white cells invade the tooth. Even though cells cannot cross the calcium barrier, nutrients can get through to nourish the isolated bacteria, and the toxins can flow into the body unimpeded, to set up disease. There is intense resistance from the dental profession to admit to the potential of root canal teeth being a primary source of “incurable” diseases today. The legal profession and insurance carriers aren’t anxious to confront these problems. The root canal tooth can then start the usually silent process of ischemic osteonecrosis (cavitations) in the bone marrow, that can then spread and destroy the blood vessels and nerves supplying adjacent teeth.

 Millions of people are ill, suffering from degenerative diseases for which the medical profession is at a loss regarding cause and treatment; the degenerative disease problem continues to bankrupt our people and country. Once a “root-canal” is done to a tooth, the pulp is gone (sacrificed) – which makes a root canal tooth a dead tooth–an expensive, dead tooth. Now the protoplasm in these miles and miles of dentinal tubules dies, and these tubules become a “dandy” place for bacteria to hang out. They have “free eats” on the dead, decaying protoplasm in the tubules.

 These tubules are 1 to 1.3 microns in diameter–big enough to accommodate bacteria, but too small to allow entry of white blood cells (which are the body’s principal way of controlling excessive bacterial populations). Now your root-canal tooth becomes a bacteria factory. The bacteria now are cloistered away from the body’s defenses and thus have free reign to proliferate. Existing inside the tooth, these bacteria have no access to air so they mutate into the anaerobic form–the kind that can live in the absence of air. When the bacteria mutate, their metabolism changes so that they give off waste products that are incredibly toxic. These toxins include thio-ethers, thio-ethanols, and mercaptans 

 Preparation techniques

In essence, it is possible to differentiate between techniques based on instrument rotation from those based on filing. In general, for curved root canals, a rotating/scraping use of root canal instruments (reaming action) leads to better preparation results than filing. 
Furthermore it is possible to differentiate generally between techniques that widen the root canal using a coronal to apical approach and those that use an apical to coronal approach to instrumentation. 

Preparation techniques using the apical to coronal approach	Preparation techniques using the coronal to apical approach
Standardised technique	Crown down pressureless technique
Step back technique	Step down technique
Circumferential filing technique	Double flare technique
Anti-curvature filing technique
Balanced force technique

In the apical to coronal approach techniques, it is first the apical segment and then the coronal segment that is instrumented.
Coronal to apical approaches envisage a step by step widening of the root canal from the crown down to the apical segment. 
Such techniques are intended to prevent the contents of the infected root canal being compressed during instrumentation into the apical canal segment or even into the peri-apical tissue. 
In essence, there is less danger of unintentionally transferring the infected contents of the root canal into the peri-apical tissue during root canal preparation when using a rotational/scraping method than when filing.

Preparation techniques using an apical to coronal approach

The step back technique

The step back technique is considered to be the standard when executing a manual canal preparation.

Initially, the apical canal cross section is widened by 3 to 4 ISO sizes with K-files. Then the length of the working section is reduced step by step by 0.5 to 1 mm and, by alternating a reduction and the master file, the preparation is completed up to the crown. The last root canal instrument that can be inserted the full length of the working section is referred to as the apical master file.  If correctly executed, this modus operandi will result in a conical canal shape with a conicity of 5%. Pronounced curvature (> 20°) and tight radii make the instrumentation more difficult. Pre-bending the instruments or the use of stainless steel files with higher elasticity, which are intended to centralise themselves automatically along the length of the canal, reduce preparatory problems. Because of canal cleansing problems, the step back technique is nowadays increasingly viewed unfavourably.

The balanced force technique

The balanced force technique caowadays be considered to be the standard method for the manual preparation of curved root canals. 
This technique takes as its starting point the advantage of rotational preparation using instruments based on the K-file principle fitted with non-cutting instrument tips.  The flexible K-files are inserted into the root canal with light apical pressure while being rotated through 90° to 180° in a clockwise direction. During the final rotation through 120 to 180°, which, while maintaining the apical pressure, is executed in an anti-clockwise direction, dental hard substance is cut away. Then the file is extracted while being rotated in a clockwise direction. This working method is continued until the apical preparation cross section has been widened by 3 to 4 ISO sizes.

Circumferential filing and anti-curvature filing technique

Circumferential filing aims to achieve a peripherally even treatment of the canal wall by means of a filing working method in the case of irregularly shaped root canals (e.g. the C-shaped root canal found in the distal root of the lower molars).
This procedure is contra-indicated in a decentralised canal position. In that case the anti-curvature filing technique is to be recommended, so as to protect the inner curve which is nearer to the surface of the root and prevent a (so-called stripping) perforation.

Preparation techniques using a coronal to apical approach

The step down technique

The step down technique is to be recommended especially in the case of narrow and/or severely curved root canals. 

The first step, once the preparation length has been determined, is to widen the coronal part of the root canal (a) and then to prepare the apical canal segment (b). The straight canal section is widened using Hedstroem files and smoothened with a Gates-Glidden’s drill. Then the curved section is instrumented by means of a rotating/scraping working method using flexible instruments with a non-cutting tip.

The crown down technique

As in the step down technique, the crown down technique prescribes the use of preparatory instruments (ISO 30 to 35) and Gates-Glidden’s drills to widen the canal in the coronal segment. Should the instrument begin to stick, narrower instruments are used to continue the preparation through the apical segment until the apex is reached. Once the working length has been reached, preparation is continued until completion using the step back technique. 
This preparation technique should be the method of choice in the case of mechanical root canal preparation.