Pathological abrasion of hard
tooth tissues. Etiology, pathogenesis, clinic forms diagnostics. Orthopedic
treatments pathological abrasion. Complications pathological abrasion of hard
tooth tissues.
Tooth abrasion can be defined as the permanent loss of tooth
structure that can occur on various tooth surfaces including the cutting
surface outer enamel layer and even exposed root surfaces.
Tooth abrasion is not caused by one method alone but by numerous
different activities. The main cause however can be due to brushing your teeth
incorrectly. Brushing your teeth to hard to fast or even using the wrong
toothpaste can lead to serious tooth abrasion. Other causes of tooth abrasion
include grinding your teeth using your teeth as a cutting tool and chewing on
hard objects.
Tooth abrasion can affect all types of people although the risk of
tooth abrasion is higher amongst people who suffer with gum disease. Gum
disease causes the teeth to pull away from the gum exposing the root of the
tooth. This leaves the root area beneath the teeth exposed to water and other
agents that the tooth enamel normally protects it against.
Definitions sometimes assume that all
dental abrasion is pathological. For example, Imfeld defined abrasion as ‘the
pathological wearing away of dental
hard tissue through abnormal mechanical processes involving foreign objects or substances
repeatedly introduced in the mouth and contacting the teeth’. However, it has
been suggested that many dental health problems are caused or exacerbated
by almost the complete lack of abrasive wear from the diet in modern Western
populations and it is accepted that even normal tooth-cleaning
practices produce some abrasion of dentine over a lifetime.
Given
that tooth-cleaning habits are highly beneficial at the same time as being the most common cause
of abrasion, it would seem reasonable to remove the words pathological and
abnormal from the above definition. This is not to deny that abusive use of
toothbrushes and toothpaste can produce pathological levels of abrasion, as
parafunction can with attrition. In
Western populations, the major abrasive agent is toothpaste, which affects dentine much
more than enamel. The evidence identifying toothbrushing with toothpaste as the
main agent in dentine abrasion is drawn from clinical data and studies in
vitro. In toothbrushing abrasion, the toothbrush itself is merely the delivery
vehicle, since brushing without paste has no effect on enamel and clinically
minuscule effects on dentine. Nevertheless,
features of the toothbrush, notably filament arrangement, density and texture, can
modulate the abrasivity of toothpaste . Toothbrushing wear is time-dependent
and appears to be influenced by many factors, including the frequency, duration
and force of brushing . The sites of predilection for dentine wear seem
to be correlated with toothbrushing habits; the sides, teeth and sites at most
risk are those known to receive most attention during brushing. The major factor in
dentine wear appears to be the relative dentine abrasivity (RDA) of the
toothpaste, which is its abrasivity relative to a standard paste, which has an RDA set at
100, determined using an International Standards Organisation (ISO)
laboratory test. ISO stipulates that the RDA of toothpastes should not exceed 250
but most toothpastes in developed countries have RDA _100. Difficulties
arise in extrapolating RDA to clinical outcome. Only
dentifrices with high relative enamel abrasivities (REA) cause appreciable
rates of enamel wear, usually because they use non-hydrated alumina, which is harder than
enamel. Dentifrices with relative enamel abrasivities _10 produce very little
wear of enamel in vitro or in situ. It has been concluded that normal
toothbrushing habits with toothpastes that conform with the ISO standard will,
in a lifetime’s use, cause virtually no wear of enamel and
clinically insignificant abrasion of dentine (a figure of 1 mm in around 100
years is often cited.
Abrasion,
derived from the Latin verb abradere, nhrasi, ahrasum (to scrape off,),
describes the wearing away of a
substance or structure through mechanical processes, such as
grinding, rubbing or scraping. The clinical term dental
abrasion or abrasio dentium is used to
describe the pathological wearing away of dental hard tissue through abnormal
mechanical processes involving foreign objects or substances repeatedly
introduced in the mouth and contacting the teeth. Depending
on the etiology, the pattern of wear can be diffuse or localized. Based on the clinical observation of the
frequent coincidence of smooth-surface and/or
cervical abrasion and extensive oral hygiene, the latter has been incriminated to be a
main etiological factor in dental
abrasion . Both patient factors and material factors have been found
to influence the prevalence of abrasion.
Patient factors include brushing technique, frequency of
brushing, time spent on brushing,
force applied during brushing, where on
the dental arch brushing is
started, etc. Material factors refer to type of material, stiffness and end-rounding of toothbrush
bristles, tufted sign of the
brush, flexibility and
length of the toothbrush grip,
as well as abrasiveness, pH and amount
of dentifrice used. Abrasion on proximal tooth surfaces may be
caused by extensive use of interdental cleaning devices such as tooth
picks or interdental brushes, especially
when they are inserted along with toothpaste or toothpowder.
Occupational abrasion, i.e. excessive tooth wear due to any professional cause
such as abrasive dust at the work place, holding nails between the teeth biting thread, etc. are
only rarely seen today.
CLASSIFICATION
pathological abrasion of teeth
Classification
of pathological abrasion of teeth. This classification includes various
clinical aspects of functional and morphological character stage of
development, depth, length, area damage and functional impairment.
Depending
on the stage of development are distinguished:
1)
physiological abrasion - within the enamel;
2)
a transitional stage of development - within the enamel, partially dentin:
3)
pathological stage of development - within the dentin (with reduced occlusal
height and without reduction).
Depending
on the severity and depth:
First
degree- to the 1/3 height of the crown;
Second
degree - from 1/3 to 2/3 the height of the crown:
Third
degree -from 2/3 the height of the crown to the gums.
Depending
on the duration of lesions:
1)
limited pathological abrasion;
2)general
pathological abrasion.
Depending
on changes in dentin sensitivity:
1)
in the normal range;
2)
with hyperesthesia.
Interaction
of Dental Abrasion with Erosion
Exposure of enamel to acid renders it
more vulnerable to abrasion. Rats drinking
an acidic drink instead of water showed occlusal and lingual wear of the molars, whether
they were consuming soft or hard food . In vitro, softened enamel is more
susceptible to abrasion, not only by toothbrush and paste , but even by such mild
challenges as toothbrushing without paste or friction from the
tongue . Thus, whereas enamel is scarcely abraded by normal toothbrushing,
it becomes vulnerable to toothbrush abrasion after erosive challenge. There is a gradient of
mineral loss in softened enamel and the outer extremities of
the crystals are thinned and would be extremely vulnerable to mechanical forces. A
physical challenge probably removes only the outer, more
demineralised part of the softened enamel to leave the inner, less demineralised part . It
can be conjectured that abraded softened enamel surfaces would be more
susceptible to fresh acid challenges, but this has yet to be tested experimentally.
It was found that brushing simultaneously with exposure to citric acid enhanced
wear by about 50% compared with brushing after acid exposure . The increase
is probably due to a primarily increased rate of mineral dissolution because of
increased fluid movement , which will result in more rapid creation
and breakage of thinned crystal extremities. Several studies have
shown that acid-softened dentine is also vulnerable to toothbrush abrasion.
Occlusal Wear
Several
studies have found that occlusal wear may be related to a variety of factors, including
occlusal variations, dusty environments, salivary variables and intake of acidic
foods and drinks. These observations suggest that erosion, abrasion or
both probably contribute to occlusal wear. From detailed observation of tooth
surfaces it was concluded that erosion was a major factor in heavy occlusal wear
in one Australian sample, except in anterior teeth of positively-identified
bruxers .The limited in vitro data suggest that erosive softening of dental
tissues is likely to increase abrasive wear but not attritional wear. This is
consistent with the finding that the total amount of wear on molars of rats drinking
an erosive liquid did not depend on the hardness of the food. Persons
subsisting on a raw-food diet, which was both fibrous and with a high acid content,
developed marked occlusal wear, with cupping of the exposed dentine . The
similarity of the pattern of wear to that in a mediaeval population with an
abrasive diet suggested that an erosive diet softens the occlusal surfaces and
makes them vulnerable to wear even by weakly abrasive materials, such as raw vegetables,
which would not affect sound dentine. An index for assessing clinical wear and
for predicting the future rate of wear
would be useful. Information on tooth wear in relation to age exists for various populations,
mostly historical . Richards et al. used
such data to
develop a mathematical model of the normal progression of wear with age. While this approach has
great potential, its successful application in a particular population requires
that the wear data on which it is based are derived from the same population or
one very like it.
Cervical Wear
The
most common sites for abnormal tooth wear are the buccal cervical regions and there has
been considerable interest in the aetiology of this wear process, thoroughly
reviewed by Levitch et al. . Obviously, a direct role for attrition in creation
of these lesions can be ruled out. Recognition of the synergy between erosion
and mechanical wear has led most researchers to consider these to be
erosion/abrasion lesions rather than the often-described cervicalAddy/Shellis
26 abrasion
lesions. Erosion must be a factor in any lesion involving enamel since, as discussed above,
most modern dentifrices produce very little wear of enamel. The abfraction
hypothesis has drawn attention to the possibility that unusual occlusal loads,
resulting from tooth misalignment or heavy muscular force, may be associated with
non-carious cervical lesions, but the evidence for this is not conclusive. Studies
which considered cervical lesion characteristics in relation to occlusal wear or
malocclusion suggest that the proportion
of lesions possibly
due to abfraction was 15–38%. Khan et al.
found saucer-shaped lesions
to be associated strongly with occlusal erosion, while wedge-shaped lesions were associated
equally with occlusal erosion and attrition.
Cervical lesions of all kinds
were much more prevalent in persons eating an erosive rawfood diet than in
controls, but were absent in a sample of mediaeval dentitions with heavy occlusal
wear . However, the latter could be due to reduced eccentric loading or
other causes . In a case-control study , only variables considered to be
related to abrasion were significant risk factors for cervical lesions in a
subject-level model, while variables related to tooth flexure and erosion were also
significant risk factors in a tooth-level model. In summary, the evidence suggests that
non-carious cervical lesions have a multifactorial aetiology, with combined
erosion and abrasion probably playing the dominant role.
Saliva and Tooth
Wear
The
importance of saliva as a lubricant has been alluded to above. Saliva is also the
source of the acquired pellicle, which reduces the amount of mineral loss in
short-term erosion. However, during acid exposure, the pellicle is removed except for the
dense basal layer and its protective effect is lost.
Thus,
to determine whether pellicle protects against repeated erosive and abrasive
challenges it is important to determine how quickly the protective effect is re-established. In
vitro tests indicate that a significant protective effect is achieved after exposure
to saliva for 2 min for dentine and 1 h for enamel. The pellicle seems to
show some resistance to brushing, since the basal pellicle layer survives
10 s brushing with saliva alone . Brushing with hydrated alumina or
saliva/silica slurry was reported to leave a thin pellicle layer on enamel and
Hannig suggested that this layer could modify wear. However, brushing with
these abrasives would cause no significant wear of sound enamel
and this hypothesis needs to be tested using softened enamel. Moreover, the
finding that brushing removes the outer pellicle substantiates the suggestion
that brushing immediately before eating or drinking might reduce
the protective effect of the pellicle against erosion. Softened enamel exposed
to a remineralising solution or to saliva for an adequate time can
regain mineral and thus re-acquire mechanical strength.
In
vivo saliva could thus reduce the vulnerability of softened dentalhard tissues
to mechanical wear. In vitro, resistance to toothbrush abrasion or to
ultrasonication was restored after exposure to artificial saliva for 4and 6 h,
respectively. In vivo results over times that would be useful in terms of
reducing abrasion of softened enamel have been less encouraging. In one in situ
experiment, only partial resistance to brushing abrasion was acquired after 60
min exposure to saliva while in another the decrease in abrasion after the same
time was not significant The discrepancy between the in vitro and in situ
results might be due to the presence in saliva of proteins (e.g. statherins)
known to inhibit hydroxyapatite crystal growth, and their absence from the
artificial salivas used in in vitro experiments. As regards dentine, exposure
to saliva seems to be ineffective in restoring abrasion resistance within a
useful time. In vitro exposure to artificial saliva for up to 2 h or for 24 h
produced no improvement in resistance to subsequent mechanical
challenge. One in situ study showed no effect on abrasion resistance after
exposure to saliva for 1 h . In another there was a numerical decrease in
abrasion resistance after 30 and 60 min remineralisation but in neither case was the tissue loss significantly
different from that in specimens brushed immediately after erosion. While
artificial caries lesions of dentine can be remineralised in vitro , it is not
complete even after 20 weeks, and remineralisation of such lesions seems to
take place by re-growth of residual mineral crystals. In erosive dentine
lesions, the superficial layer seems to be completely demineralised and
Clarkson et al. showed that dentine demineralised by organic acids does not
remineralise because it retains phosphoproteins which may act as inhibitors.
Longevity
of Restorative Materials and Acidic Conditions
The
longevity of dental restorations depends on the durability of the material per
se and its wear resistance , the durability of the interface between tooth
substance and restoration, the level of tooth destruction, its location and
load.
In
a study, three glass-ionomer restorative materials used for cervical
erosion/abrasion lesions were evaluated clinically after 10 years. The authors
concluded that when a noninvasive approach is desired, glass-ionomer materials
are the restorative material of choice for this kind of lesion because of their
longterm retention values . It has to be kept in mind that at the time of this
study total-etch dentinal adhesive systems were still improving and hardly any
system showed, clinically, restoration margins free of microleakage for an
extended time Gaengler et al. evaluated
the longevity of posterior glass-ionomer
cement/composite
restorations after an examination period of 10 years. They found that the early
risk of failure was attributed to bulk fractures and partial loss of filling
material. The maximum longevity was a maximum of 74% over 10 years. It was
concluded that this form of posterior restoration was clinically appropriate
because a high percentage of restorations had correct anatomical form and
demonstrated a low secondary caries rate. Future treatment regimes have been
made possible by the development of sophisticated preparation techniques,
improved adhesive systems and restorative materials that will result in the
therapy of more small-sized lesions rather than large restorations. Indirect
inlay techniques will shift towards direct restorative techniques. As the
cavities become smaller, it is to be expected that the use of improved direct
restorative materials will provide excellent longevity even in load-bearing
situation.
In
patients with severe tooth surface loss on more than two surfaces per tooth and
extended loss of vertical dimension, a complex reconstruction with indirect
restorations (ceramic crowns, bridges) is often inevitable. This measure should
be restricted to very advanced erosion cases .As in other patients with erosive
tooth wear adequate preventive measures and recall intervals must be executed.
Dental
occlusion is the manner in which the top and
bottom teeth come into contact with one another, whether at rest or while
chewing. That is, whether you're resting or chewing, dental occlusion has to do
with how your teeth touch and whether or not they are in a healthy alignment
with one another.
Static occlusion
refers to the relationship between the bottom and top teeth when the jaw is
still and stationary. Static occlusion is observed and measured when the mouth
is at rest.
Centric
occlusion is the way the teeth fit together when the jaw is closed; it's the
way the teeth align during normal and comfortable biting. Centric occlusion in
which all the teeth are correctly aligned is desired, with no overbite,
cross-bite or underbite.
Malocclusion is
characterized by teeth that are misaligned and do not fit together properly.
This can result in an over bite, underbite or an incorrect bite, which can
cause numerous health problems that extend beyond the dental realm.
Malocclusion can
cause problems involving the teeth and gums. Fillings and crowns can break or
wear out quicker than normal, or teeth are generally sore and gums recede.
Temporomandibular joint or TMJ problems can also result, causing clicking,
grinding and pain in the jaw joint. Some people experience buzzing in the ear.
When undue strain is placed on the jaw muscles, people with malocclusion can
experience fatigue in their muscles. This can translate into headaches, sinus
problems, neck and shoulder pain and muscle spasms.
When poor dental
occlusion or malocclusion is experienced, occlusal trauma can result. This
trauma is made apparent in several ways including pain, the movement of teeth
including crowding, the feeling that the teeth are always mobile and the
wearing down of the facets of the teeth on inappropriate areas.
HARD TISSUE OF TEETH
We know that throughout life there is
abrasion of enamel and dentin. Under normal conditions, this process is
physiological in nature and begins immediately upon the teeth in contact with
each other physiological abrasion of hard tooth tissue occurs in two planes -
horizontal and vertical. Clearing in the horizontal plane is observed on the
cutting edge of incisors and canines as well tubercles molars and premolars.
This reduction bite can be explained as adaptive reaction. In the case of
vertical abrasion abrasion of hard tissue occurs on the contact surfaces, which
eventually leads to the formation of contact points to the pads. Physiological
wear off expressed in different people in different ways. Some patients younger
than 50 years of clinical wearing off identify difficult-pathological abrasion
of hard tooth tissues characterized by rapid and progressive decrease in size
of natural teeth. This process, once begun, practically stops. and constantly
progressing.
Pathological wearing off teeth observed
in the case of bruxism . Bruxism - the unconscious (often nightly) compression
or conventional automatic movements lower jaw, accompanied by grinding teeth.
Bruxism refers to parafunction of the group distorted features. With one of the
reasons for the emergence and development of a generalized pathological
abrasion of teeth. Treatment developed enough. Patients require a comprehensive
examination of the dentist, a neurologist and psychiatrist. With the use of
orthopedic occlusive caps for the entire dental series of hard or soft plastic
base plate .
One of the causes of abnormal abrasion
of teeth is their acid necrosis. It is observed in the chemical industry
workers who have contact with hydrochloric, nitric and other acids. If spilled
acid on the teeth with the flow of air as vapor and subsequent dissolution in
saliva is decalcification of enamel especially front teeth. Immediate action
devastating acid on the tooth appears primarily on organic substances.
In the case of vertical abrasion
abrasion of hard tooth tissues occurs at the contact surfaces that eventually
leads to the formation of contact points to the pads. Physiological stertist
expressed in different people in different ways. Some patients younger than 50
years of clinical stertist difficult to determine.
Pathological abrasion of hard tooth
tissues characterized by rapid and progressive decrease in size of natural
teeth. This process, once started, almost stops, and continually progresses.
Pathological wearing off teeth has
polyetiological form of the disease. The occurrence of this disease involves
both endogenous and exogenous factors. Not exclude the role of disturbances of
mineral metabolism, which is basically concomitant somatic disease. Of great
importance are also factors such as the effect of chemical agents, particularly
extended time. Pathological abrasion fo tooth develops from mechanical
overload, which is usually the result of loss of teeth.
Another clinical picture observed by a
generalized form of pathological abrasion of teeth. Patients with this form of
abrasion are divided into two groups. The first group includes patients with
generalized abrasion whoch covers all teeth, but reduce the height of the lower
third of the face is not happening due to a compensatory increase in alveolar
ridge and collar pieces that are massive and increasing in volume. Do not
change position of the head and lower jaw in articular hollow.
The second group includes patients with
generalized form of pathological abrasion which is not compensated by the growth
and increase in the amount of alveolar bone and, as a result there is a marked
reduction of the lower third of the face. Reducing the distal face is
characterized by shortening of the upper lip, nasolabial folds and under chin
pronounced, corners of his mouth dropped, his face in such patients become
senile specific look.
Due to the fact that this pathology is
changing the position of the mandible relative to the top and head position of
the mandible to the articular hollow, they are shifted backwards and down. This
placement heads mandible leads to redistribution and functional overload joint,
which may be the cause of deforming arthritis and related pathological symptoms
(tinnitus, hearing loss, nasal tinnitus, dry mouth, etc.).
Due to the decrease in the height of the
lower third of the face and reduces the distance between the points of
attachment of the masticatory muscles, which negatively affects their work and
eventually leads to a decrease in chewing efficiency.
Pathological abrasion teeth often
combined with partial loss of teeth, secondary deformities, distal displacement
of the mandible, manifested complex clinical picture.
Orthopedic treatment in case of
pathological abrasion of hard tissue teeth
Before drawing up a plan of orthopedic treatment of the patient with abnormal
abrasion of teeth should be examined in detail. In a study to determine the
most likely causative factor in abnormal abrasion, shape and degree of
(localized, generalized, compensated, decompensated), clinical and radiological
status crowns and periodontal tissues of the teeth, pulp condition they may
change the appearance of the patient, the condition of temporomandibular joint.
In the process of collecting medical
history to find out whether there was a similar disease in close relatives.
Older people interpret, whether this disease in their children. Particular
attention should be paid to the interpretation of conditions.
Clinical and radiological examination of
oral tissues facilitates treatment plan and the optimal method.
Preparing patients for orthopedic
treatment must include rehabilitation of the mouth. Tooth extraction is carried
out after a thorough examination of bone and periodontal tissues of the
inclusion complex survey electro excitability of pulp, which in this disease is usually
reduced. Removing teeth be amended near the apex tissues, impassable canals,
teeth that have no functional value, which can not produce stump tab.
During the compilation of the previous
treatment plan should be carried out differential diagnosis occlusal
disturbances caused by tooth-collar extending from strains with different
pathogenesis. In case of loss of chewing teeth front group performs a mixed
function, which leads to a shortening of their clinical crowns due to abrasion
of enamel and dentin.
Orthopaedic treatment in the event of
abnormal abrasion of teeth has both therapeutic and prophylactic purpose. At
first realize improved chewing function and appearance of the patient, in the
second - to prevent abrasion of hard tooth tissue and disease prevention TMJ.
Specific tasks in the orthopedic treatment of a particular patient depends on
clinical features.
Before drawing up a plan of orthopedic
treatment of the patient with abnormal abrasion teeth necessary to analyze the
clinical situation to determine how to restore intercoronal height, taking into
account data study of height in the lower third of the face of a state of
physiological rest and the central value of the jaws.
You
must pay attention to the X-ray data TMJ.
In
the case of localized and generalized forms of abrasion without changing the
height of the lower third of the face can be used such methods are the most
common orthopedic care. If abnormal abrasion caused changes in the aesthetic
sense, then you need to plan measures include orthopedic prosthesis hard tooth
tissue cores inset piece and structures with facing modern materials depending
on the prosthesis.
In
severe cases, when the process started, except to prevent further progression
of the patient return appearance by restoring anatomical shape of crowns. In
this case it is necessary to increase coronal height in the anterior or
throughout the dentition. In the first clinical case to the front group of
teeth made removable plate or metal caps, parting bite in lateral parts, which
leads to regression of alveolar bone and parts in the front. This approach is
effective in younger patients, in elderly restructuring collar bone and part of
it may not happen, then you need to increase the height coronal if it can make
a fortune TMJ. Increasing coronal height
necessary to carry out the restructuring miostatic reflexes in several stages.
In the extreme case, when all the applied methods are ineffective, it is
necessary to remove the front of the teeth if they are cult at gingival margin.
If
abnormal abrasion, accompanied by a decrease in the lower third of the face,
the task is much more complicated prosthesis. In this case, it is necessary not
only to improve the function of mastication, but also to prevent further tooth
wear. At the same time we have to increase the height coronal that will change
the appearance of the patient and to normalize the position of the head of the
mandible in the articular fossa.
Increasing
coronal height achieved restoration of form and height erased crowns of natural
teeth, which requires use piece design, since all the others on this disease
are ineffective and short-lived.
Partial
loss of teeth can occur against the backdrop of an existing pathological
abrasion of teeth. On the other hand, the loss of molars and premolars can
cause abnormal wear of the front group of teeth from a mixed function that they
have to perform. The clinical picture in this case is complicated, because the
abnormal abrasion attached clinic partial loss of teeth. The tasks that need to
be addressed during the prosthesis when abnormal abrasion of teeth, added more
problems and partial replacement of defects of teeth. Orthopedic design dentures,
which are used to solve the latter problem, conditioned by the particular
clinical picture. If included defects without reducing distal face can be used
fixed-piece prostheses. If reduction of distal face prosthetics provides
restoration of dentition defects and mandatory in coronal height in all
surviving teeth. This can be achieved fully if used piece prosthetic
appliances.
In the presence
of end defects as unilateral and bilateral, shows the use of different designs
of removable dentures.
Tooth
abrasion can occur gradually over a period of time or very quickly. Gradual
tooth abrasion allows the body to reduce the severity of tooth abrasion as the
body has sufficient time to repair itself. The body does this by allowing a new
layer of dentin (the layer immediately under the outer tooth enamel layer) to
be deposited over the damaged areas of the tooth. This new layer of dentin
prevents the nerves blood vessels and connective tissue inside the tooth known
as the pulp from being damaged further and therefore enables the tooth to heal.
Quick
tooth abrasion on the other hand can cause irreversible damage to the pulp and
lead to the consequences of tooth abrasion which not only include crocked teeth
but also increased tooth sensitivity infection and ultimately loss of the
tooth.
CLASSIFICATION:
class 0 - no abrasion,
class 1 - abrasion of enamel,
class 2 - abrasion with revealed
dentine,
class 3 - abrasion of dental
occlusion,
class 4 - abrasion of a tooth’s
crown to the point of
revealed tooth’s neck,
class
5 - abrasion with the tooth’s chamber opened.
One of the most
common types of damage that occurs in the mouth is called Toothbrush Abrasion.
I see it in about 8 out of 10 people. Toothbrush abrasion is an innocuous
problem stemming from a bad habit that can lead to receded gums, sensitive
teeth, holes cut into teeth, strange esthetics and tooth loss.
Introduction
For starters,
take your toothbrush and move it back and forth along your skin. If you rub it
like this enough times in the same area and with enough pressure, you will
cause your skin to turn red and it may hurt. If you kept up this pace, your
brush may eventually cause damage to your skin, cause a little bleeding, and
hurt a lot. Now, please don’t try this for real, but you get the idea.
Fortunately,
brushing the skin is not something most of us do, even though the outer skin is
a tough layer of protection and will stand up pretty well against a toothbrush.
However,
brushing the teeth is a daily exercise that all of us must do. When you take
your toothbrush and carry it to the mouth, it is going to meet two things:
something very hard (your teeth) and other things very soft (your gums, your
tongue, etc.).
The enamel of
teeth is the hardest substance in the human body, almost like rock, and very
hard to break or otherwise do damage to. Enamel in adult teeth has years to
form, which partly explains where this strength comes from. Enamel makes up the
outermost layer of teeth when you look in the mirror.
Teeth are
encircled by a fragile, thin, easy to damage layer of skin called the gums.
Their most fragile spot than at that junction where the teeth meet the pink of
the gums (called the gumline). It is at this point that toothbrush abrasion
comes into the picture, because this is precisely the area in your mouth that
is most vulnerable to damage from brushing one’s teeth too hard, leading to
what is called toothbrush abrasion.
The
Cause of Toothbrush Abrasion
We all brush our
teeth every day. The goal of brushing is to remove food particles from around
the teeth to render them clean and our breath feeling fresh. Food usually
collects in the form of “plaque”, which is that whitish material that likes to
hang around the gumline. So when you take your toothbrush, you are carrying it
around the teeth, but often also against the gumline and maybe a little bit
higher onto the gums themselves. So you brush and you brush and you brush and
you’re done, great.
However, if you
put too much force on the toothbrush as you go around, your gums don’t like it
(remember the skin example). Keeping in mind that the gums are very fragile and
weak, they really can’t stand up to this excessive force for too long. What
happens over time is that the gums will actually recede- (in protest?) and you
will have given yourself a receded gumline.
Gum
Recession from Toothbrush Abrasion
Gum recession
caused by toothbrushing is not the same thing gum disease, which is caused by
bacteria and infection. This recession is caused by you. You have brushed too
hard, too frequently, with too much force, too much on the gums, for too long,
and now it is too late, your gum has disappeared. Maybe you pushed too hard
because you were stressed or not paying attention. No matter what the reason,
once the gum is gone, it is gone and it “‘aint ever gonna grow back”. You have
receded gums and- you’re (gasp!) only 25, or 30 or 35 or whatever and you
thought all your life that gum recession was only a problem for “old people”.
As you can see, if the cause of the recession is toothbrushing, it can occur at
any age, young and old.
One of the most common
types of damage that occurs in the mouth is called Toothbrush Abrasion. I see
it in about 8 out of 10 people. Toothbrush abrasion is an innocuous problem
stemming from a bad habit that can lead to receded gums, sensitive teeth, holes
cut into teeth, strange esthetics and tooth loss.
Introduction
For starters, take your
toothbrush and move it back and forth along your skin. If you rub it like this
enough times in the same area and with enough pressure, you will cause your
skin to turn red and it may hurt. If you kept up this pace, your brush may
eventually cause damage to your skin, cause a little bleeding, and hurt a lot.
Now, please don’t try this for real, but you get the idea.
Fortunately, brushing the
skin is not something most of us do, even though the outer skin is a tough
layer of protection and will stand up pretty well against a toothbrush.
However, brushing the
teeth is a daily exercise that all of us must do. When you take your toothbrush
and carry it to the mouth, it is going to meet two things: something very hard
(your teeth) and other things very soft (your gums, your tongue, etc.).
The enamel of teeth is the
hardest substance in the human body, almost like rock, and very hard to break
or otherwise do damage to. Enamel in adult teeth has years to form, which
partly explains where this strength comes from. Enamel makes up the outermost
layer of teeth when you look in the mirror.
Teeth are encircled by a
fragile, thin, easy to damage layer of skin called the gums. Their most fragile
spot than at that junction where the teeth meet the pink of the gums (called
the gumline). It is at this point that toothbrush abrasion comes into the
picture, because this is precisely the area in your mouth that is most
vulnerable to damage from brushing one’s teeth too hard, leading to what is
called toothbrush abrasion.
The Cause of Toothbrush
Abrasion
We all brush our teeth
every day. The goal of brushing is to remove food particles from around the
teeth to render them clean and our breath feeling fresh. Food usually collects
in the form of “plaque”, which is that whitish material that likes to hang
around the gumline. So when you take your toothbrush, you are carrying it
around the teeth, but often also against the gumline and maybe a little bit
higher onto the gums themselves. So you brush and you brush and you brush and
you’re done, great.
However, if you put too
much force on the toothbrush as you go around, your gums don’t like it
(remember the skin example). Keeping in mind that the gums are very fragile and
weak, they really can’t stand up to this excessive force for too long. What
happens over time is that the gums will actually recede- (in protest?) and you
will have given yourself a receded gumline.
Gum Recession from
Toothbrush Abrasion
Gum recession caused by
toothbrushing is not the same thing gum disease, which is caused by bacteria
and infection. This recession is caused by you. You have brushed too hard, too
frequently, with too much force, too much on the gums, for too long, and now it
is too late, your gum has disappeared. Maybe you pushed too hard because you
were stressed or not paying attention. No matter what the reason, once the gum
is gone, it is gone and it “‘aint ever gonna grow back”. You have receded gums
and- you’re (gasp!) only 25, or 30 or 35 or whatever and you thought all your
life that gum recession was only a problem for “old people”. As you can see, if
the cause of the recession is toothbrushing, it can occur at any age, young and
old.
Sensitivity in The Teeth
If a recession of the
gumline has occurred, most people will first take notice of a sensitivity when
something cold or sweet touches the side of the affected tooth while eating,
drinking or breathing air. Sometimes also a pain occurs during toothbrushing as
the bristles move across the side of the tooth. Why is this related?
As the gumline recedes due
to excessive toothbrushing forces, it begins to expose a part of the tooth
which is normally kept covered up by the gums. This part of the tooth is called
the dentin, which is where the nerve endings are. As a result of the dentin
being exposed, the nerve endings contained within also become exposed and the
result is the sensitivity to cold, sweet or touching of the area.
The dentin is a layer
underneath the enamel, but as you go down into the root of the tooth, the
enamel slowly gets thinner and thinner until it stops about 1/3 of the way
down. This is where the underlying dentin starts to show through and takes it
the rest of the way down the root to the tip of the tooth. Where the enamel has
stopped and the dentin takes over is called the dentin-enamel junction, which
usually happens to be just below the gumline. If the gumline has receded,
however, this junction becomes exposed and the dentin sensitivity becomes
apparent.
If the gumline recession
is minor, de-sensitizing materials can be placed over the exposed dentin to
seal the nerve endings and make the patient comfortable. One popular material
is potassium nitrate, contained in “sensitivity” toothpastes. Upon using a
toothpaste containing it, it blocks the nerve endings, but it takes two weeks
for enough to build up to give a noticeable result. Indeed if the person stops
using the product, the material goes away and they are sensitive again. The
other downside is that the toothpaste itself may not be what is needed in the
rest of the mouth (maybe the person needs a tartar control toothpaste, or an
anti-gingivitis formula), so it means a lot of toothpaste in the house.
Finally, the overzealous person will attempt to brush the sensitivity
toothpaste into the tooth vigorously, causing further gumline recession and
worsening the problem.
A better solution is a
desensitizing solution that is applied in the dental office directly to exposed
sensitive dentin areas only. The chemical is then sealed into place, completely
blocking the nerve endings. It is invisible, works instantly, offers
long-lasting protection and is cheaper than buying tube after tube of special
toothpaste.
Holes cut into teeth
As the gumline recedes and
the dentin is exposed, not only does sensitivity become a problem, but the
dentin itself can be literally cut away by the toothbrush if a bad forceful
brushing technique is continued to be used.
The dentin is softer
compared to enamel. While toothbrushing cannot easily cause harm to enamel, the
dentin however, is quite easily damaged. Once a receded gumline has exposed
enough dentin, the toothbrush can easily start to cut a hole into the tooth at
this point. After a months of abuse, the hole will have grown to resemble a
notch.
A smaller notch, if caught
early, may not need any treatment other than desensitizer to keep the patient
comfortable from the exposed dentin. However, a deeper notch will always
require treatment to fill in the notch.
If the notch is left
exposed, food and bacteria become trapped in hidden corners and this will lead
to tooth decay (a cavity). Decay that occurs in the dentin notch will quickly
eat away and destroy the tooth, resulting in pain and more complicated
treatment like a root canal becoming necessary.
To treat a deeper notch,
the treatment consists of a filling, usually of tooth-colored filling material
applied directly to the notch to fill it in. This not only gives the tooth its
correct contour back, but it covers up all exposed dentin, shutting off any
sensitivity. This is a very common treatment.
Tooth Loss
A
deeper notch, sometimes cutting as much as halfway into the tooth like a
lumberjack saws a tree before it is about to be felled, will eventually weaken
the tooth so much that just like the tree, the tooth will break, cracking out
of the mouth when the person bites hard.
Yet
even continued brushing too hard, with continuing recession of the gumline
without necessarily any notching, will cause more and more of the tooth to be
exposed. As the gum shrinks towards the tip of the root, the tooth loses
support from the gums. Eventually the tooth may get loose and fall out due to
simply not having enough gum around it to hold it up.
Esthetics due to Toothbrush Abrasion
Patients
often ask why there is a yellow part of the tooth at the gumline. That is the
dentin, it is always yellow. If the patient has brushed too hard and gumline
has receded due to toothbrush abrasion, more of the dentin will be exposed,
causing a “yellow teeth” esthetic problem. Sometimes tooth-colored filling
material can be placed as a “patch” to cover up the yellow areas.
Treatment for Toothbrush abrasion
First
and foremost is to stop the bad brushing habit. Keep brushing, but do so with a
soft toothbrush, a light touch and with an up and down motion against the teeth
to minimize destruction. It doesn’t matter if the toothbrush is manual or
electric, both types can cause the same problem.
Since
the gum doesn’t grow back, as long as the patient is comfortable, without
sensitivity or deep notches, it can be left like that.
Some
patients with high esthetic requirements opt to have plastic surgery on the
gums to reposition the gums back into place or to cut out gum from another part
of the mouth in order to cover up the teeth where the gumline has receded.
Information
contained is generalized. Sensitivity of any kind may be an indicator of more a
serious dental and/or overall health condition. This advice is not intended to
be self-diagnostic nor may it be relevant to your particular condition and
cannot be used to replace a dental examination.
Treatment of dental
erosion depends on the severity of the damage. If the loss of tooth enamel is
moderate without affecting the patient’s appearance, there is no need of
restorative treatment. The dentist may recommend certain fluoride
treatments and de-sensitizing toothpastes to control the tooth
sensitivity symptoms caused by teeth erosion. Enhancing the re-mineralization
process by providing minerals such as fluoride may be enough for natural tooth enamel
restoration. The dentist may also apply a fluoride varnish on the affected
teeth for further protection and repair of tooth enamel.
Restorative cosmetic
treatments
become necessary if the tooth enamel damage is extensive. Depending on the
degree of tooth wear, restorative treatment can range from placement of bonded
composites (tooth bonding) in a few isolated areas
of teeth erosion, to crowns, dental porcelain veneers, bridges or even full
mouth reconstruction in the case of severe tooth enamel damage. A cosmetic
dentist has to evaluate the situation and recommend the best cosmetic treatment
to restore teeth function and appearance.
Treatment of beginning form of pathological abrasion
without TMJ disorders:
Production of metal
inlays, or cast metal crowns on the molars & premolars and their
antagonists on both sides.
Treatment of gyperesthesia
( desensitizing substances, pastes with fluoride, electrophoresis of 10%
solution of CaCl, calcium gluconate)
Forms of pathological abrasion of the teeth:
Vertical
Horizontal
Mixed
Types of
pathological abrasion of the teeth:
Local
Generalized
² group – patients with the whole
teeth row abrasion, but without decreasing of the lower third of the face. It
is compensated with alveolar bone growing.
²² group – decompensated form.
Sensitivity
in The Teeth
If a recession
of the gumline has occurred, most people will first take notice of a
sensitivity when something cold or sweet touches the side of the affected tooth
while eating, drinking or breathing air. Sometimes also a pain occurs during
toothbrushing as the bristles move across the side of the tooth. Why is this
related?
As the gumline
recedes due to excessive toothbrushing forces, it begins to expose a part of
the tooth which is normally kept covered up by the gums. This part of the tooth
is called the dentin, which is where the nerve endings are. As a result of the
dentin being exposed, the nerve endings contained within also become exposed
and the result is the sensitivity to cold, sweet or touching of the area.
The dentin is a
layer underneath the enamel, but as you go down into the root of the tooth, the
enamel slowly gets thinner and thinner until it stops about 1/3 of the way
down. This is where the underlying dentin starts to show through and takes it
the rest of the way down the root to the tip of the tooth. Where the enamel has
stopped and the dentin takes over is called the dentin-enamel junction, which
usually happens to be just below the gumline. If the gumline has receded,
however, this junction becomes exposed and the dentin sensitivity becomes
apparent.
If the gumline
recession is minor, de-sensitizing materials can be placed over the exposed
dentin to seal the nerve endings and make the patient comfortable. One popular
material is potassium nitrate, contained in “sensitivity” toothpastes. Upon
using a toothpaste containing it, it blocks the nerve endings, but it takes two
weeks for enough to build up to give a noticeable result. Indeed if the person
stops using the product, the material goes away and they are sensitive again.
The other downside is that the toothpaste itself may not be what is needed in
the rest of the mouth (maybe the person needs a tartar control toothpaste, or
an anti-gingivitis formula), so it means a lot of toothpaste in the house.
Finally, the overzealous person will attempt to brush the sensitivity
toothpaste into the tooth vigorously, causing further gumline recession and
worsening the problem.
A better
solution is a desensitizing solution that is applied in the dental office
directly to exposed sensitive dentin areas only. The chemical is then sealed
into place, completely blocking the nerve endings. It is invisible, works
instantly, offers long-lasting protection and is cheaper than buying tube after
tube of special toothpaste.
Holes
cut into teeth
As the gumline
recedes and the dentin is exposed, not only does sensitivity become a problem,
but the dentin itself can be literally cut away by the toothbrush if a bad
forceful brushing technique is continued to be used.
The dentin is
softer compared to enamel. While toothbrushing cannot easily cause harm to
enamel, the dentin however, is quite easily damaged. Once a receded gumline has
exposed enough dentin, the toothbrush can easily start to cut a hole into the
tooth at this point. After a months of abuse, the hole will have grown to
resemble a notch.
A smaller notch,
if caught early, may not need any treatment other than desensitizer to keep the
patient comfortable from the exposed dentin. However, a deeper notch will
always require treatment to fill in the notch.
If the notch is
left exposed, food and bacteria become trapped in hidden corners and this will
lead to tooth decay (a cavity). Decay that occurs in the dentin notch will
quickly eat away and destroy the tooth, resulting in pain and more complicated
treatment like a root canal becoming necessary.
To treat a
deeper notch, the treatment consists of a filling, usually of tooth-colored
filling material applied directly to the notch to fill it in. This not only
gives the tooth its correct contour back, but it covers up all exposed dentin,
shutting off any sensitivity. This is a very common treatment.
Tooth
Loss
A deeper notch,
sometimes cutting as much as halfway into the tooth like a lumberjack saws a
tree before it is about to be felled, will eventually weaken the tooth so much
that just like the tree, the tooth will break, cracking out of the mouth when
the person bites hard.
Yet even
continued brushing too hard, with continuing recession of the gumline without
necessarily any notching, will cause more and more of the tooth to be exposed.
As the gum shrinks towards the tip of the root, the tooth loses support from
the gums. Eventually the tooth may get loose and fall out due to simply not
having enough gum around it to hold it up.
Esthetics
due to Toothbrush Abrasion
Patients often
ask why there is a yellow part of the tooth at the gumline. That is the dentin,
it is always yellow. If the patient has brushed too hard and gumline has
receded due to toothbrush abrasion, more of the dentin will be exposed, causing
a “yellow teeth” esthetic problem. Sometimes tooth-colored filling material can
be placed as a “patch” to cover up the yellow areas.
Treatment
for Toothbrush abrasion
First and
foremost is to stop the bad brushing habit. Keep brushing, but do so with a
soft toothbrush, a light touch and with an up and down motion against the teeth
to minimize destruction. It doesn’t matter if the toothbrush is manual or
electric, both types can cause the same problem.
Since the gum
doesn’t grow back, as long as the patient is comfortable, without sensitivity
or deep notches, it can be left like that.
Some patients
with high esthetic requirements opt to have plastic surgery on the gums to
reposition the gums back into place or to cut out gum from another part of the
mouth in order to cover up the teeth where the gumline has receded.
Information
contained is generalized. Sensitivity of any kind may be an indicator of more a
serious dental and/or overall health condition. This advice is not intended to
be self-diagnostic nor may it be relevant to your particular condition and
cannot be used to replace a dental examination.
Treatment of
dental erosion depends on the severity of the damage. If the loss of tooth
enamel is moderate without affecting the patient’s appearance, there is no need
of restorative treatment. The dentist may recommend certain fluoride
treatments and de-sensitizing toothpastes to control the tooth
sensitivity symptoms caused by teeth erosion. Enhancing the re-mineralization
process by providing minerals such as fluoride may be enough for natural tooth
enamel restoration. The dentist may also apply a fluoride varnish on the
affected teeth for further protection and repair of tooth enamel.
Restorative
cosmetic treatments become necessary if
the tooth enamel damage is extensive. Depending on the degree of tooth wear,
restorative treatment can range from placement of bonded composites (tooth
bonding) in a few isolated
areas of teeth erosion, to crowns, dental
porcelain veneers,
bridges or even full mouth reconstruction in the case of severe tooth enamel damage.
A cosmetic dentist has to evaluate the situation and recommend the best
cosmetic treatment to restore teeth function and appearance.
Dental Erosion:
A challenge for the 21st century! This monograph offers a guide towards better
oral health in the future. Erosive tooth wear is a multifactorial condition of
growing concern to the clinician and the subject of extensive research – a view
supported by the literature and impressions from many international conferences
over recent decades. However, until now, no attempt has been made to collect
and organize the available information in a single book. This volume of onographs in Oral Science is the first
book dealing solely with erosive tooth wear. The thirteen chapters of the book
present a broad spectrum of views on dental erosion, from the molecular level
to behavioral aspects and trends in society.
The
multifactorial etiological pattern of erosive tooth wear is emphasized and is a
strand connecting the different chapters of the book. It starts with the
definition of erosion and describes the interaction of attrition, abrasion and
erosion in tooth wear. The chapters on diagnosis of erosion, and prevalence,
incidence and distribution of the condition are followed by a chapter on the
chemistry of erosion. Under the heading extrinsic causes of erosion, several
factors are analyzed and illustrated, amongst which are the consequences of our
changing life styles and the effects of oral hygiene products and acidic
medicines. The chapter on intrinsic causes of erosion focuses on
gastroesophageal reflux disease and related issues. A separate chapter is
devoted to dental erosion in children. Methods of assessment of dental erosion
are presented and critically evaluated, concluding that the complex nature of
erosive mineral loss and dissolution might not readily be encompassed by a
single technique: a more comprehensive approach combining several different
methods is recommended. The last three chapters cover dentinal
hypersensitivity, risk assessment and preventive measures, and, finally,
restorative options for erosive lesions.
Each chapter has
a comprehensive list of references, encouraging the reader to consult the
original articles for more details. Instructive intraoral photographs
illustrate the text and guide the reader. An unusual step is that every chapter
was reviewed not only by the editor, but also by two external reviewers,
ensuring the highest of standards. This monograph describes current concepts of
dental erosion and presents an overview of the literature, with special
reference to clinically relevant implications. It is not only suitable for
faculty members and researchers, but may also be recommended for dental
students, practitioners and other dental professionals who are committed to
preventing and treating dental erosion.
Erosive
Tooth Wear – A Multifactorial Condition of Growing Concern and Increasing
Knowledge
Abstract
Dental
erosion is often described solely as a surface phenomenon, unlike caries where
it has been established that the destructive effects involve both the surface
and the subsurface region. However, besides removal and softening of the
surface, erosion may show dissolution of mineral underneath the surface. There is
some evidence that the presence of this condition is growing steadily. Hence,
erosive tooth wear is becoming increasingly significant in the management of
the long-term health of the dentition. What is considered as an acceptable
amount of wear is dependent on the anticipated lifespan of the dentition and,
therefore, is different for deciduous compared to permanent teeth. However,
erosive damage to the permanent teeth occurring in childhood may compromise the
growing child’s dentition for their entire lifetime and may require repeated
and increasingly complex and expensive restoration.
Therefore,
it is important that diagnosis of the tooth wear process in children and adults
is made early and adequate preventive measures are undertaken. These measures
can only be initiated when the risk factors are known and interactions between
them are present. A scheme is proposed which allows the possible risk factors
and their relation to each other to be examined.
Change
of Perception
Erosive
tooth wear has for many years been a condition of little interest to clinical
dental practice or dental public health. Diagnosis was seldom made, especially
in the early stages, and there was little if anything that could be done to
intervene in the early stages. However, perceptions are now changing.
‘Etiology,
mechanisms and implications of dental erosions’ was published. It was stated in
the preface that dental erosion is an area of research and clinical practice
that will undoubtedly experience expansion in the next decade. Indeed,in the
last decade erosion has attracted a great amount of research, with subsequent
progression in the field. Whilst in the 1970s less than 5 studies per year were
published about erosion, this number was still below 10 in the 1980s and has nowadays
increased to about 50 studies per year. (Erosive) tooth wear is becoming
increasingly significant in the long term health of the dentition and the
overall well-being of those who suffer its effects. Following the decline in
tooth loss in the 20th century, the increasing longevity of teeth in the 21st
century will render the clinically deleterious effect of wear more demanding
upon the preventive and restorative skills of the dental professional.
Awareness of dental erosion by the public is still not widespread, and dental
professionals worldwide are sometimes confused by its signs and symptoms, and
its similarities and differences from the other categories of tooth wear namely
abrasion, attrition and abfraction. In its earl y stages, and for the vast majority
of the population, the changes seen in tooth erosion are of only cosmetic
significance. In a survey in England, 34% of the children were aware of tooth
erosion but only
8%
could recall their dentist mentioning the condition. Forty percent of children
believed incorrectly that the best way to avoid erosion was regular
toothbrushing which shows some lack of information or misunderstanding. In
addition, the awareness of dentists was considered low.
Change
of Consumption of Acidic Foods and Beverages
As
lifestyles have changed through the decades, the total amount and frequency of
consumption of acidic foods and drinks have also changed. Soft drink
consumption in the USA increased by 300% in 20 years, and serving sizes
increased from 185 g (6.6 oz) in the 1950s to 340 g (12 oz) in the 1960s and to
570 g (20 oz) in the late 1990s. Around the year 1995, between 56 and 85% of
children at school in the USA consumed at least one soft drink daily with the
highest amounts ingested by adolescent males. Of this group, 20% consumed four
or more servings daily. Studies in children and adults have shown that this
number of servings per day is associated with the presence and progression of
erosion when other risk factors are present. It becomes obvious that with the increased
popularity of soft drinks the consumption of milk may decrease in children and
adolescents, which could result in calcium deficiency, thus jeopardizing the
accrual of maximal peak bone mass at a critical time in life.
Change
of Prevalence of Erosion
National
dental surveys are not routinely undertaken and when conducted seldom have
included measures of tooth wear, specifically erosion. Erosion was first
included in the UK childrens’ dental health survey in 1993 and is repeated
periodically. The prevalence of erosion was seen to have increased from the
time of the children’s dental health survey in 1993 to the study of 4- to
18-year-olds in 1996/1997. There was a trend towards a higher prevalence of
erosion in children aged between 3 1/2 and 4 1/2 years, and in those who
consumed carbonated drinks on most days, compared with toddlers consuming these
drinks less often. In another UK study, 1,308 children were examined at the age
of 12 years and 2 years later. Five percent of the subjects aged 12 years and
13% 2 years later had deep enamel lesions. Dentinal lesions were found in 2% of
the examined subjects at the age of 12 years and rose to 9% 2 years later. The
incidence of new cases also increased. Twelve percent of 12-year-old children
who demonstrated no evidence of erosion developed the condition over the
subsequent 2 years. New and more advanced lesions were seen in 27% of the
children over the study period. Active erosive lesions will progress when no
adequate preventive measures are implemented (figs. 1–3). To determine the
progression of erosive defects 55 persons were examined twice on two occasions
six years apart. All persons were informed about the risk of erosive tooth wear
but no active preventive care during the study period was performed. A distinct
progression of erosion on occlusal and facial surfaces was found. The
occurrence of occlusal erosions with involvement of dentine rose from 3 to 8%
(26–30-years-old at the first examination) and from 8 to 26% (46–50-years-old
at the first examination). The increase in facial erosions was smaller but
again more marked for the older group. In this longitudinal study, the
subjective evaluation of dentine hypersensitivity remained unchanged despite
the marked increase of erosive and wedgeshaped defects. Dentine
hypersensitivity is a relatively common phenomenon and tooth wear, specifically
erosion, has been implicated as a predisposing factor. However, no conclusive
data are available which would show an increase of dentine hypersensitivity
with increasing acidic consumption or erosive tooth wear. Clearly, more
research is needed in this field.
Early
Diagnosis
Early diagnosis
is important. Dental professionals will typically ignore or overlook the very
early stages dismissing minor tooth surface loss as a normal and inevitable
occurrence of daily living, being ‘within normal limits’ and thus not
appropriate for any specific interventive activity. Only at the later stages in
which dentine has become exposed and possibly sensitive, and the appearance and
shape of the teeth altered that the condition becomes evident at routine
examination. There is no device available for the specific detection of dental
erosion in routine practice. Therefore, the clinical appearance is the most
important feature for dental professionals to diagnose dental erosion. This is
of particular importance in the early stage of erosive tooth wear. The
appearance of a smooth silky-glazed appearance, intact enamel along the
gingival margin, change in color and cupping and grooving on occlusal surfaces
are some typical signs of early erosion. However, it is difficult to diagnose
erosion at an early stage and it can be very difficult to determine if dentine
is exposed or not. Even if a clinician is able to diagnose tooth wear, the differential
diagnosis of erosion, abrasion or attrition may be a challenge either through
lack of awareness of the multifactorial and overlying etiologies. It is
possible to use disclosing agents to render dentine involvement visible. Only a
dentist with the diagnostic capability of distinguishing early erosion from the
other noncarious defects will be in a position to deliver timely preventive
measures. Indeed, these conditions may occur simultaneously. In children, the
most commonly reported areas with wear are occlusal surfaces of molars (fig. 3)
and incisal surfaces of incisors. These surfaces are also associated with
attrition and it can be difficult to separate what is being caused by erosion
from what is being caused by other tooth wear factors. For these and other
reasons the terms ‘erosion’ and ‘erosive tooth wear’ are used in this book
interchangeably demonstrating the overlapping nature of this condition.
Occlusal
erosive tooth wear with involvement of dentine with a composite filling rising
above the level of the adjacent tooth surface. Age of the patient: 30 years.
Known risk factors: soft drinks (sip-wise), gastroesophageal reflux.
Same
patient as in figure 1 (5 years later). The progression on the premolars and on
the first molar is clearly visible.
Occlusal
erosive tooth wear of a child aged 14 years. He suffered from dentine
hypersensitivity. Known risk factors: gastroesophageal reflux, ice tea, acidic
beverages. Same patient 2 1/2 years later. Progression is clearly visible.
Change
of Knowledge and Risk Factors
Erosion
is often described solely as a surface phenomenon, unlike caries where it has
been established that the destructive effects are both on the surface and
within the subsurface region. However, the pathophysiology of erosion is more
complex. When a solution comes in contact, with enamel, it has to diffuse first
through the acquired pellicle and only thereafter can it interact with enamel.
The acquired pellicle is a biofilm, free of bacteria, covering oral hard and
soft tissues. It is composed of mucins, glycoproteins and proteins, amongst
which are several enzymes. On the surface of enamel, the acid with its hydrogen
ion (or a chelating agent) will start to dissolve the enamel crystal. First,
the prism sheath area and then the prism core are dissolved, leaving the
well-known honeycomb appearance. Fresh, unionized acid will then eventually
diffuse into the interprismatic areas of enamel and dissolve further mineral
underneath the surface, in the sub-surface region. This will lead to an outflow
of ions and subsequently to a local pH rise in the tooth substance and in the
liquid surface layer in close proximity to the enamel surface. The events in
dentine are in principle the same but are even more complex. Due to the high
content of organic material, diffusion of the demineralizing agent (i.e. acid)
deeper into the region and the outward flux of tooth mineral are hindered by
the organic dentine matrix. It has been assumed that the organic dentine matrix
has a sufficient buffering capacity to retard further demineralization and that
chemical or mechanical degradation of the dentine matrix promotes
demineralization.
These
erosive processes are halted when no new acids and/or chelating substances are
provided. An increase in agitation (e.g. when a drink is swished around the
mouth) will enhance the dissolution process because the solution on the surface
layer adjacent to enamel will be readily renewed. Further, the amount of drink
in the mouth in relation to the amount and flow of saliva present will modify
the process of dissolution. There are many more factors which are involved in
and interact with erosive tooth wear. Figure is an attempt to reveal the
multifactorial predisposing factors and etiologies of the erosive condition,
which seems to be steadily rising in western societies. Many biological,
behavioral and chemical factors are interacting with the tooth surface, which
over time, may either wear it away, or indeed protect it depending upon their
fine balance. Hydrogen ion concentration (pH) alone does not explain erosive
potential of a foodstuff; titratable acidity, calcium, phosphate, luoride levels and other factors must also be
considered. The interplay of all these factors is crucial and helps explain why
some individuals exhibit more erosion than others, even if they are exposed to
exactly the same acid challenge in their diets. In the initial stage a certain
degree of repair should be possible as there is a subsurface component of the
process which is symbolized with the short (back reaction) arrow in figure 4.
As known in the carious process the factors listed in the outer circle will
influence the whole process of erosion development or defense further.
Comprehensive knowledge of the different risk and protective factors is a
prerequisite to initiate adequate preventive measures. People who show signs
and symptoms of erosion are often not aware of, and may easily be confused by,
the erosive potential of some drinks and foodstuffs. Only when a comprehensive
case history is undertaken will all the risk factors be revealed. However, a
thorough knowledge of the erosive potential of drinks and foodstuffs is needed
by the dentist, to determine the patient’s risk and to bring it in to context
with the behavioral and biological factors. Knowing these factors, the reported
symptoms (thermal or tactile sensitivity) and signs evident on clinical
examination, and putting them in relation to the wishes, hopes and
possibilities of the individual patient enables the dentist to initiate
adequate preventive (noninterventive) and therapeutic (interventive) measures.
When a restoration becomes inevitable, in all situations, the preparations have
to follow the principles of minimally invasive treatment. In no case may early
diagnosis of erosive tooth wear be an excuse for a restoration. Instead
preventive measures must be initiated to reduce the erosive challenge and to
increase the protective and defensive factors thus bringing this equilibrium
back to the oral environment.
Diagnosis
of Erosive Tooth Wear
Abstract
The clinical
diagnosis ‘erosion’ is made from characteristic deviations from the original
anatomical tooth morphology, thus, distinguishing acid induced tissue loss from
other forms of wear. Primary pathognomonic features are shallow concavities on
smooth surfaces occurring coronal from the enamel–cementum junction. Problems
from diagnosing occlusal surfaces and exposed dentine are discussed. Indices for
recording erosive wear include morphological as well as quantitative criteria.
Currently, various indices are used making the comparison of prevalence studies
difficult. The most important and frequently used indices are described. In
addition to recording erosive lesions, the assessment of progression is
important as the indication of treatment measures depends on erosion activity.
A number of evaluated and sensitive methods for in vitro and in situ approaches
are available, but the fundamental problem for their clinical use is the lack
of re-identifiable reference areas. Tools for clinical monitoring are
described.
Current
Approach to Erosive Tooth Wear
‘Diagnosis is
the intellectual course that integrates information obtained by clinical
examination of the teeth, use of diagnostic aids, conversation with the patient
and biological knowledge. A proper diagnosis cannot be performed without
inspecting the teeth and their immediate surroundings’. This definition
formulated for caries is also true for erosive tooth wear. It means that a grid
pattern of criteria is pelted over the patient and thereafter the signs and
symptoms are first ordered and then classified in the second step. In the same
process, the native tooth anatomy and morphology memorized engram-like is
compared with the actual appearance. The different chemical and physical
insults on teeth cause loss of dental hard tissue with some characteristic
patterns. The classification of wear is made from clinically observed
morphological features. However, some indices do assume information as to the
etiology such as attrition, abrasion and erosion. This approach is open to
debate for two reasons: (1) an association between defect morphology and the
respective etiological factors has not been validly established, and (2) the
presumed etiology predetermines scientific strategies and could introduce bias.
It has therefore been argued that assessing wear as the super ordinate
phenomenon disregarding the shape of lesions would overcome these disadvantages.
It is, however, important to note that the tissue loss ceases from progression
when the cause is eliminated. Therefore, on a patient level it is a
prerequisite to detect the condition early, to distinguish it from other
defects and to search for the main cause in order to start the adequate
preventive measures. From a clinical as well as from a scientific point of
view, it would be necessary to have differentiating diagnostic criteria
available.
Morphology
and Differential Diagnosis of Erosive Tooth Wear
The early signs
of erosive tooth wear appear as a smooth silky-shining glazed surface. In the
more advanced stages changes in the original morphology occur. On smooth
surfaces, the convex areas flatten or concavities become present, the width of
which clearly exceeds its depth. Undulating borders of the lesion are possible.
Initial lesions are located coronal from the enamel–cementum junction with an
intact border of enamel along the gingival margin. The reason for the preserved
enamel band could be due to some plaque remnants, which act as a diffusion
barrier for acids or due to an acid-neutralizing effect of the sulcular fluid,
which has a pH between 7.5 and 8.0. Further acid attacks can lead to
pseudo-chamfers at the margin of the eroded surface.
Erosion can be
distinguished from wedge-shaped defects, which are located at or apical to the
enamel–cementum junction. The coronal part of wedge-shaped defects ideally has
a sharp margin and cuts at right angles into the enamel surface, whereas the
apical part bottoms out to the root surface. The depth of the defect clearly
exceeds its width. The initial features of erosion on occlusal and incisal
surfaces are the same as described above. Further progression of occlusal
erosion leads to a rounding of the
cusps, grooves on the cusps and incisal edges, and restorations rising
above the level of the adjacent tooth surfaces. In severe cases the whole
occlusal morphology disappears. Erosive lesions have to be distinguished from
attrition. They are often flat and have glossy areas with distinct margins and
corresponding features at the antagonistic teeth. Much more difficult is the
distinction between occlusal erosion and abrasion/demastication, which
sometimes are of similar shape. Whenever possible, the clinical examination
should be accomplished by a thorough history taking with respect to general
health, diet and habits and by the assessment of saliva flow rates.
Facial
erosive tooth wear. Note the intact enamel along the gingival margin and the
silky-glazed appearance of the tooth. Age of patient: 28 years. Known
etiological factors: acidic drinks, gastroesophageal reflux.
Facial
erosive tooth wear. No intact enamel along the gingival margin, but a
silky-glazed appearance of the surface. Age of patient: 35 years. Known
etiological factors: acidic fruits (lemon, orange) and fresh squeezed lemon and
orange juice.
Severe
facial erosive tooth wear. Age of patient: 25 years. Known etiological factors:
lemon slices under the lip, fruit juices.
Occlusal
erosive tooth wear. Note rounding of the cusps and grooves. Age of patient: 29
years. Known etiological factors: soft drinks, sipping of 0.5-l acidic sports
drinks per day.
Occlusal
erosive tooth wear. Age of patient: 29 years. The signs of erosive tooth wear
are more pronounced. Known etiological factors: soft drinks, sipping of 0.5-l
acidic sports drinks per day
Severe
occlusal erosive tooth wear. No occlusal morphology present. Age of patient: 29
years. Known etiological factor: gastroesophageal reflux.
Severe
oral and occlusal erosive tooth wear. Note the worn oral cusps and the amalgam
filling rising above the level of the adjacent tooth surface. Age of patient:
29 years. Known etiological factor: gastroesophageal reflux.
Indices
Erosive
tooth wear from a clinical view is a surface phenomenon, occurring on areas
accessible to visual diagnosis. The diagnostic procedure is therefore a visual
rather than instrumental approach. A number of indices for the clinical diagnosis
of erosive tooth wear have been proposed, which more or less are modifications
or combinations of the indices published by Eccles and Smith and Knight. All
erosion indices include diagnostic criteria to differentiate erosions from
other forms of tooth wear, and criteria for the quantification of hard tissue
loss. The size of the area affected is often given as the proportion of the
affected to the sound tooth surface. The depth of a defect is estimated by
using the criterion of dentine exposition. Thereby, a relation between exposed
dentine and amount of substance loss is implicated. Most working groups have
developed their own index modifications which had not yet reached broader use.
Frequently used indices with particular regard to erosions are the indices used
in the British Children’s National Health and National Diet and Nutrition
Surveys and the index suggested by Lussi.
Two
items included in the erosion indices are currently under discussion: The
morphological criteria for occlusal/incisal surfaces are not strongly
associated with erosive tissue loss. A study including subjects with
substantially different nutrition patterns (an abrasive, an acidic, and an
average western diet.
Severe oral erosive tooth wear. Note the intact enamel
along the gingival margin. Age of patient: 28 years. Known etiological factor:
gastroesophageal reflux.
Severe oral erosive tooth wear. Note the intact
cervical enamel band and the pulp
shining through.
No endodontic complications or dental complaints. Age of patient: 29 years.
Known
etiological factor: Eating disorder (free from chronic vomiting for a couple of
y ears).