This document discusses several acquired abnormalities of teeth including attrition, abrasion, erosion, resorption, secondary dentin formation, pulp stones, and hypercementosis. Attrition is the wearing down of teeth due to normal function and presents as wear facets. Abrasion is non-physiological wearing caused by external agents like toothbrushes and presents as notching. Erosion is chemical wearing by acids and presents as smooth lesions. Resorption can be internal, external, or a combination and is caused by trauma, pressure or tumors. Secondary dentin formation occurs with aging or stimuli and decreases pulp size. Pulp stones are calcifications within the pulp that are common in older people. Hypercementosis
5. Attrition
Attrition: It is the physiologic wearing of
teeth due to function between the maxillary and
mandibular teeth.
Sites: incisal edges, occlusal surfaces and contact
areas.
Factors affecting attrition: nature of diet, salivary
factors, mineralization of teeth, emotional tension
(e.g.bruxism) and as part of the aging process.
7. Radiographic Appearance
Crowns have plane
surfaces instead of
curved ones.
Short crown.
Absence of opaque
enamel.
decrease size of pulp
chamber by deposition
of secondary dentine.
May be complete
obliteration of the pulp.
May be associated
with hypercementosis.
DD: recognition by
history, sites, extent.
10. Abrasion
It is non-physiological wearing
away of teeth by some external
agent e.g. a toothbrush or
toothpick.
Causes: friction, occupational
hazards or habits e.g. tooth
brush trauma , pipe smoking,
hard food, the use of some
dentifrices. trauma from tooth
picks or dental floss.
Other habits include opening
hair pins, cutting thread nail
biting or
13. Abrasion: Tooth brush trauma
Most severe in the CEJ on the
labiobial and buccal surfaces of
premolars, canines and incisors.
Also involving the root surfaces.
Commonly occurs on the
opposite side of the hand used.
No pulp exposure due to continuous deposition of
Secondary dentine.
18. Abrasion: Dental floss injury
Clinical feature
Seen in the cervical portion of the
proximal surface, just above the
gingiva.
Radiographic feature:
Seminlunar radiolucency in the
interproximal surfaces
DD
1.Cervical caries.
2.Cervical burn out.
20. Erosion
It is a chemical wearing away of tooth structure
due to prolonged contact with acids.
Causes:
acidic food (e.g. citrus fruits).
Chronic vomiting.
Chemical fumes in industries.
22. Erosion: Clinically
Sites:
• labial surfaces of incisors.
• Involves multiple teeth .
Shape: smooth, glistering, may
be pink in color.
Radiographically: RL spots
which could be defined by
clinical exam and history.
25. Resorbtion
I. Physiologic: in the process of shedding.
II. Pathologic:
1. pressure
2.chronic inflammation.
3- associated with tumors or cyst.
26. Types of resorbition
Internal
starting in the pulp tissue.
Affecting surface dentine.
Unknown cause or may be:
due to direct or indirect
trauma, pulp capping,
pulpotomy, dens-in-dent,
pulp polyp.
External
occurs at the lateral. surfaces
of the root.
due to trauma, pressure or
orthodontic treatment.
Or internal- external
• starting at the cementum
• then invade dentine from the
pulp side.
28. Clinical Picture of resorbition
Internal
permanent> deciduous
pulp chamber:
if dentin only: Dark tooth
involve enamel: pink tooth
if more: may be perforation.
root:
if extensive: root fracture.
may communicate with deep
period. pocket.
External
mand.>, # 1> # 3 ># 4,5.
Idiopathic resorbtions may occur
in younger age (18-25ys). Also
in old age.
Has no clinical symptoms
EXCEPT non-specific pain
or disturbed crown/root ratio.
29. Radiographic Picture of resorpition
Internal
general widening of pulp
chamber.
Or localized well defined
smooth area without evidence
of calcification.
DD: difficult from B or L
caries. But caries is more
diffuse + clinical evaluation.
30.
31. Radiographic Picture of resorpition
External
involves the root apex or
lateral surface.
Apical end is straight.
If laterally: irregular out-line.
external resorption may
affect unerupted tooth and
that time it may affect crown
or root.
34. Secondary Dentin Formation
It is the process by which
secondary dentine is
formed after formation of
teeth.
Causes:
aging
secondary to occlusal
forces, slight trauma, deep
caries, fracture crown,
attrition, abrasion or
erosion, .
35. Secondary dentine: Clinically and
Radiographically
Clinically: Decreased tooth sensitivity
Radiographically: secondary dentin is indistinguishable
from primary dentin EXCEPT for decrease size of the
pulp.
In aging: over all reduction of pulp size.
Due to stimulus: localized reduced pulp size related to
the location of the stimulus.
42. Pulp Stone
It is an area of calcification within
the pulp.
Of unknown origin.
Frequency: very common in young
adult and almost in all old people.
may reach to 3mm in size.
May be single or multiple.
43. Pulp Stones
Round or oval radiopacity.
Occurs in the pulp chamber
or root canal.
single or multiple
Clinically:
no signs or symptoms.
45. Hypercementosis
Def: excessive deposition of cementum
Causes:
unknown or due to
Over eruption due to loss of the antagonist.
Local inflammation.
traumatic occlusion
associated with Paget’s disease.
Significance: difficulty in tooth extraction.