2. The primary cause of tooth substance loss is
dental caries, however, there are certain other
noncarious conditions, which eventually result
in loss of tooth structure.
The cervical area, which is located in the
gingival one third of the facial and lingual
tooth surfaces, is an area that exhibits unique
clinical characteristics.
4. I. Abrasion
Definition- Abrasion is the abnormal tooth
surface loss resulting from direct forces of
friction between teeth and external objects or
from frictional forces between contacting
teeth components in the presence of an
abrasive medium.
5.
6. Etiology-
Abrasion may occur from:
1. Improper brushing habit
Factors influencing the role of tooth brushing in
abrasion are
i. Brushing technique
ii. Brushing force
iii. Bristle stiffness
iv. Time
v. Frequency
2. Habits such as holding a pipe stem between teeth.
3. Tobacco chewing
4. Vigorous use of toothpicks between adjacent teeth.
7. • Tooth brush abrasion is the most common
example and usually seen as a V-shaped notch
in the gingival portion of the facial aspect of a
tooth.
• The surface of the defect is usually smooth.
8. II. Erosion
Definition- Erosion is the wear or loss of tooth
surface by chemicomechanical action in the
continued presence of demineralizing agents
with low pH.
9.
10. Classification:
I. Intrinsic erosion
This is a form of erosion caused due to
endogeneous acids of gastric origin.
1. Recurrent vomiting
i. Eating disorders
a. Anorexia nervosa- Associated with extreme
dietary restriction and profound weight loss.
b. Bulimia nervosa- Associated with repeated
episodes of binge eating and self-induced
vomiting.
11. ii. Medical Conditions
a. Gastrointestinal disorders
. Peptic ulcer
. Hiatus hernia
. Intestinal obstruction
b. Metabolic and endocrine disorders
c. Neurological disorders
. Side effect of drugs
. Psychogenic vomiting syndrome
. Chronic alcoholism and binge drinking
. Pregnancy induced vomiting
12. 2. Regurgitation
GERD (Gastroesophageal reflux disease)
Regurgitation in this disease occurs without any
nausea or abdominal contractions. Erosion occurs
when the acid reflux passes into the pharynx and
comes into contact with the lingual surfaces of
the teeth.
3. Rumination
It is a syndrome consisting of repetitive effortless
regurgitation of undigested food within minutes
after a meal. This disorder is found in young
infants.
13. II. Extrinsic erosion
Associated with extrinsic factors, common
causes of this kind of erosion-
1. Occupational factors: Professional wine
tasters, Professional swimmers
2. Diet: Citrus fruit juices, acidic beverages,
carbonated beverages
3. Medicaments: Aspirin, ascorbic acid
(vitamin C)
14. • Regurgitation of stomach acid can cause this
condition on the palatal surfaces of maxillary
teeth (particularly anterior teeth)
• Extrinsic erosion commonly leads to the
dissolution of facial aspects of anterior and
buccal aspects of posterior teeth.
15. III. Attrition
Definition- Attrition is the mechanical wear of
the incisal or occlusal surface as a result of
functional or parafunctional movements of
the mandible (tooth-to-tooth contacts).
Attrition also includes proximal surface wear at
the contact area because of physiologic tooth
movement.
16.
17. Etiology:
If significant abnormal attrition is present, the
patient’s functional movements should be
evaluated, and inquiry needs to be made
about any habits creating this problem, such
as tooth grinding, or bruxism, usually resulting
from:
Stress
Airway issues
Sleep Apnea
18. • Sometimes, the enamel of the cusp tips (or
incisal edges) is worn off, resulting in cupped-
out areas because the exposed, softer dentin
wears faster than the surrounding enamel.
• These areas causes food retention or the
presence of peripheral, ragged, sharp enamel
edges.
19. IV. Abfraction
Definition: Strong eccentric occlusal force
resulting in microfractures at the cervical area
of the tooth causing wedge- shaped defects is
termed as abfraction.
20.
21. Etiology: Abfraction is caused due to tooth flexure in
patients with abnormal occlusal interactions.
Tooth flexure during abnormal occlusal interaction
Lateral or axial bending of the tooth
Tensile and compressive stresses generated in the
cervical region
Strain leading to microfractures in cervical enamel and
tooth loss
Notch shaped abfraction lesions
22. • These lesions are characterized by sharp notch
or wedge-shaped lesions
• The maximal abfractive stresses generated are
at the cervical area in the thinnest region of
enamel at the cementoenamel junction.
24. The primary goal of management should be to
halt or modify the etiology of the problem.
Considerations for restorative management of
noncarious lesions:
1. The defect is sufficiently deep to compromise
the structural integrity of the tooth.
2. Intolerable sensitivity exists and is unresponsive
to conservative desensitizing measures.
3. The area is affected by caries.
4. The defect contribute to a periodontal problem.
25. 5. The area is to be involved in the design of a
removable partial denture.
6. The depth of the defect is judged to be close
to the pulp
7. The defect is actively progressing
8. The patient desires esthetic improvements.
26. Class V cervical tooth preparations, by
definition, are located in the gingival one third
of the facial and lingual tooth surfaces.
Because of esthetic considerations,
composites are most frequently used for the
restoration of class V lesions in anterior and
premolar teeth.
The other alternative material used in certain
clinical conditions is employing a resin
modified GIC restoration.
27. Clinical Technique for Class V Direct
Composite Restorations
Initial Clinical Procedures:
- Shade selection
- Isolation
28. Clinical Considerations:
1. Enamel bevels are usually used on the
occlusal margins of the preparation, while at
the cervical margin, enamel bevels are
usually not recommended because of the
absence of enamel in this area.
2. Class V tooth preparations will vary slightly,
depending on the type and extension of the
defect being restored.
29. Class V Tooth Preparation for small or
moderate lesions or defects that do not
extend onto the root surface:
- The objective is to restore the lesion or defect
as conservatively as possible. These include
decalcified and hypoplastic areas located in
the cervical third of the teeth.
- The initial tooth preparation is accomplished
with a round diamond or carbide bur
eliminating the entire enamel lesion or defect.
The preparation is extended into dentin only
when the defect warrants such extension.
30. - The tooth preparation for a class V abrasion or
erosion area usually requires only roughening
of the internal walls with a diamond
instrument and beveling all enamel margins.
- If necessary, the root surface cavosurface
margins should be prepared to appx 90
degrees. Often, because of the inherent form
of root surface cavosurface margins is not
needed.
31.
32. Class V Tooth Preparation for large lesions or
defects that extend onto the root surface:
- The features of the preparation include a 90
degree cavosurface margin with uniform depth of
the axial line angles.
- Groove retention form usually is not necessary
but can be used if retention form is a concern.
- Conservative enamel bevel
- The large class V preparation initially exhibits 90
degree cavosurface margins (that subsequently
can be beveled when in enamel) and an axial wall
that is uniform in depth.
33. The axial depth into dentin is determined by
the extent of the defect. Many of these larger
preparations are combination of beveled
enamel margins and 90 degree root surface
cavosurface margins.
34. Tooth Preparation:
- To initiate the preparation, a tapered fissure
carbide bur (no. 271) or similarly shaped
diamond is used at high speed with air-water
spray. If interproximal or gingival access is limited,
an appropriately sized round bur or diamond may
be used.
- When a tapered fissure bur or diamond is used,
the handpiece is maneuvered to maintain the
bur’s long axis perpendicular to the external
surface of the tooth during preparation of the
outline form, which should result in 90 degree
cavosurface margins.
35. - All of the external preparation walls of a class
V tooth preparation are visible when viewed
from a facial position (outwardly divergent
walls)
- The bevel on the enamel margin is
accomplished with a flame-shaped or round
diamond instrument, resulting in an angle
approximately 45 degrees to the external
tooth surface, and prepared to a width of at
least 0.5mm depending on the preparation
size and esthetic considerations.
36. Restorative Technique:
- Acid etching and placement of the adhesive
- Insertion and light-activation of the composite
37. Clinical Technique for Glass Ionomer
Restorations
Indications:
1. Gl possess the favorable quality of releasing
fluoride when exposed to the oral environment.
These materials also have been shown to
‘recharge’ with fluoride when exposed to
fluoride from various sources.
Because of this potential anticariogenic quality,
glass ionomer may be the material of choice for
restoring root-surface caries in patients with
high caries activity and in whom esthetics is not
as critical.
38. 2. Cervical defects of abfraction or abrasion
origin (or any combination) also may be
indications for restoration with glass
ionomers, if esthetic demands are not critical.
3. Glass ionomers can be considerd as an
alternative to composite restoration if clinical
conditions that can affect the performance of
composite restorations are present. These
factors include-
i. Decreased salivary function
ii. Decreased patient motivation or ability for
home care
39. iii. Increased difficulty in adequately isolating
the operating area.
iv. Increased difficulty in performing the
operative procedure because of the patient’s
physical or medical problems
4. Because of their limited strength and wear
resistance, glass ionomers are indicated
generally for the restoration of low-stress
areas.
40. Tooth Preparation and Restoration:
- Same as previously described, except bevels
are rarely used.
- Most conventional glass ionomer systems
require mild dentin conditioning to remove
the smear layer, effecting improved adhesion
of the glass ionomer to dentin. To condition
dentin, a mild acid, such as 10% polyacrylic
acid, is applied to the preparation, according
to manufacturer’s instructions, followed by
rinsing and removal of excess water, leaving
dentin slightly moist.
41. - Glass ionomer material should be placed into
the preparation in slight excess and quickly
shaped with a instrument.
- If a conventional glass ionomer is used, a thin
coat of light- activated, resin based coating is
placed on the surface immediately after
placement to prevent dehydration and
cracking of the restoration during the initial
setting phase. Newer GI are more resistant to
dehydration and do not typically require this
step.
42. - When the material has set, the matrix, if used, is
removed, and the gross excess is shaved away
with a No. 12 surgical blade in a Bard-Parker
handle. Contouring and finishing should be
accomplished as much as possible with hand
instruments, while striving to preserve the
smooth surface that occurs on setting.
- Micron finishing diamonds used with a petroleum
lubricant to prevent desiccation are ideal for
contouring and finishing conventional GIs. Also,
flexible abrasive disks used with a lubricant can
be effective.
43. - A fine- grit aluminium oxide polishing paste
applied with a prophy cup is used to impart a
smooth surface.
