orofacial anatomy unit 4 Dental Anomalies

Anomalies Size & Number: macrodontia

very large but normally shaped teeth

Anomalies Size & Number: microdontia

very small but normally shaped teeth

Anomalies Size & Number: anodontia

congenitally abcent of all prim or perm teeth

Anomalies Size & Number: true anodontia

Sex-linked genetic disease, faulty ectodermal development, rare

Anomalies Size & Number: partial anodontia

Congenital, 1 or more missing teeth, missing same tooth runs in family

Anomalies Size & Number Missing Teeth 1st most common

3rd molars max more than mand

Anomalies Size & Number Missing Teeth 2nd most common

max lateral incisor

Anomalies Size & Number Missing Teeth 3rd most common

mand 2nd premolars

Anomalies Size & Number least likely to be missing

canaine

Anomalies Size & Number hyperdontia

extra teeth in addition to the regular number "supernumerary"

Anomalies Size & Number supernumerary teeth conical

peg shaped teeth

Anomalies Size & Number supernumerary teeth tubercule

made of more than one cusp or tubercle. They are barrel shaped, usually invaginated.

Anomalies Size & Number supernumerary teeth supplemental

resemble normal teeth mat be an incisor premolar. molar

Anomalies Size & Number supernumerary teeth mesiodens

tooth errupting between the central incisors

Anomalies Size & Number supernumerary teeth paramolar

is a supernumary premolar

Anomalies Size & Number supernumerary teeth distomolar

small supernumery molar found distal to eights (max)

Shape Anomalies peg lateral

most common anomoly

Shape Anomalies dens in dente

anomaly of development resulting from deepening or

invagination of the enamel organ into the dental papilla, which begins at the

crown and often extends to the root, before the calcification of the dental

tissues.

• A.K.A. dens invaginatus, dilated odontome and gestant anomaly

Shape Anomalies dens in dente type 1

the invagination ends in a blind sac

Shape Anomalies dens in dente type 2

the invagination extends to the amelocemental junction, also

ending in a blind sac.

Shape Anomalies dens in dente type 3

the invagination extends to the interior of the root, providing an

opening to the periodontium, sometimes presenting another foramen in

the apical region of the tooth

Shape Anomalies complex Odontoma

the tissues are arranged in a haphazard fashion with no discernible

dental structures,

Shape Anomalies compound odontoma

the dental tissues exist in a

more regular pattern so that the lesion consists of tooth like structures

Shape Anomalies Dens evaginatus

very rare, a projection of enamel can occur on the occlusal

surface of the premolar teeth.

• It forms a tubercle called a 'dens evaginatus'.

Shape Anomalies Dilaceration

A sharp bend most often in the root of a tooth.

Shape Anomalies Dwarfed Roots

Normal sized crowns with abnormally short roots

Shape Anomalies Gemination

development of two crowns from one tooth germ, extra wide crown

Shape Anomalies fusion

union of the two adjacent tooth germs by dentin: extra wide or normal crown with extra roots

Shape Anomalies concrescence

is the joining of tooth roots by cementum - It occurs

after tooth formation is complete.

• Usually this condition is 'silent' without clinical significance. When extracting

teeth, however, radiographs are essential to the diagnosis of this condition.

Shape Anomalies Hypercementosis

It is a consequence excessive cementum deposition.

• It occurs in older people and often when there are greatly increased

occlusal forces.

Shape Anomalies Taurodontism

literally means 'bull-like teeth' - usually molars.

• They have an abnormally long pulpal chamber and shortened roots.

• The pulp chamber has no constriction near the CEJ as do normal teeth.

• Clinically these teeth appear normal

Shape Anomalies Enamel Pearls - (enamelomas)

are small nodules of enamel found on the root of

the tooth close to or at the cemento enamel junction.

• They are found most often at the bifurcation or trifurcation of molars.

• They do appear radiographically.

• While they can be a problem in periodontal disease, they should usually be left

alone as their attempted removal can do more harm than good.

Shape Anomalies Talon Cusp

or dens evaginatus of anterior teeth is a relatively rare developmental anomaly characterized by the presence of an accessory cusp like structure projecting from the cingulum area or cement-enamel junction of the maxillary or mandibular anterior teeth in both the primary and permanent dentition. • This anomalous structure is composed of normal enamel and dentin and either has varying extensions of pulp tissue into it or is devoid of a pulp horn. In its typical shape, the anomaly resembles an eagle’s talon, but it could also present as pyramidal or conical. The prevalence of talon cusp varies considerably among populations, ranging from 0.06% to 7.7%

colour anomalies Hypoplasia

underdeveloped or incomplete development of enamel

• Thinner than normal, damage to ameloblasts during matrix formation and can be

localized or generalized

colour anomalies Hypoplastic enamel causes

fevers, vit d deficiency, malnutrition, morning sickness, occurs during calcification

colour anomalies enamel hypocalcification

refers to the lack of complete deposition of calcium

into the developing tooth enamel. Hypocalcification is actually a form of

hypoplasia. Hypocalcified enamel is less calcified enamel. chalky white appearence

colour anomalies Decalcification

In decalcification, enamel erupts with a normal amount of

calcification but becomes demineralized from environmental factors (plaque)

colour anomalies Amelogenesis Imperfecta-

Form of enamel dysplasia as a result of hereditary

factors. It is the partial or total malformation of enamel. The dentin and pulp

develop normally, whereas the enamel is easily chipped or worn away.

colour anomalies Turner’s Tooth

appearance is variable, though usually is manifested as a

portion of missing or diminished enamel on permanent teeth. Unlike other

abnormalities which affect a vast number of teeth, Turner's hypoplasia usually

affects only one tooth in the mouth and, it is referred to as a Turner's tooth.

• If Turner's hypoplasia is found on a canine or a premolar, the most likely cause is

an infection that was present when the primary tooth was still in the

mouth.

colour anomalies Turner's hypoplasia

s found in the front (anterior) area of the mouth, the

most likely cause is a traumatic injury to a primary tooth. The traumatized tooth,

which is usually a maxillary central incisor, is pushed into the developing tooth

underneath it and consequently affects the formation of enamel. usually affects the tooth enamel if the trauma occurs prior to the

third year of life. Injuries occuring after this time are less likely to cause enamel

defects since the enamel is already calcified.

colour anomalies Fluorosis

Discolouration of enamel may arise from naturally occurring water

supplies or from fluoride delivered in mouthrinses, tablets or toothpastes as a

supplement. The severity is related to age and dose. The enamel is often

affected and may vary from areas of flecking to diffuse mottling, while the colour

of the enamel ranges from chalky white to a dark brown/ black

appearance. The brown/black discolouration is post-eruptive and probably

caused by the uptake of extrinsic stain into the porous enamel.

colour anomalies hutchinson’s Incisors and Mulberry Molars

are developmental anomalies that

result from congenital syphilis. Clinically, the incisor teeth are, on occasion called

'screwdriver teeth' due to their distinctive shape.

colour anomalies Dentinogenesis Imperfecta

is the irregular formation or absence of dentinal

development. It is an inherited disorder characterized by faulty formation of

connective tissues. The dentin has an increased water and organic content. The

enamel formation over it is normal but the enamel breaks away from the weak

underlying dentin easily and the teeth are prone to rapid wear and dentinal

sensitivity. Treatment usually involves the placement of crowns to preserve the

tooth structure.

colour anomalies Tetracycline Stain-

Systemic administration of tetracyclines

during development is associated with deposition of tetracycline within bone

and the dental hard tissues. Dentin has been shown to be more heavily stained

than enamel. Tetracycline is able to cross the placental barrier and should be

avoided from 16 weeks in utero until full term to prevent incorporation into the

dental tissues. Since the permanent teeth continue to develop in the infant and

young child until 12 years of age, tetracycline administration should be avoided

in children below this age and in breast-feeding and expectant mothers. The

most critical time to avoid the administration of tetracycline for the deciduous

dentition is 4-5 months in utero post-partum, with

regard to the incisor and canine teeth. In the permanent dentition, for the

incisor and canine teeth, this period is from 4 months post-partum to

approximately 7 years of age. The colour changes involved depend upon the

precise medication used, the dosage and the period of time over which the

medication was given. Teeth affected by tetracycline have a yellowish or brown￾grey appearance which is worse on eruption and diminishes with time. Exposure

to light changes the colour to brown, the anterior teeth are particularly

susceptible to light induced colour changes.

colour anomalies pulpal Haemorrhagic

The discolouration of teeth following severe trauma was

considered to be caused by pulpal haemorrhage. In vitro studies have recently

shown that the major cause of discolouration of non-infected traumatised teeth

is the accumulation of the haemoglobin molecule or other haematin molecules.

It has been shown that the pinkish hue seen initially after trauma may disappear

in 2 to 3 months if the tooth becomes revascularised.

Translocation

when a tooth errupts in the wrong spot

Ectopic Eruption

erruption of a tooth into an abnormal position in the arch

ankylosis

Fusion of the cementum or dentin to the surrounding alveolar bone.

It may occur at any age, generally occurring earlier in life (7 to 18 yrs.)

occlusal plane of the involved tooth is below that of the adjacent dentition. It

may delay the eruption of the permanent successor.

Impaction

A tooth may be impacted by hard tissue (bone or the physical

presence of another tooth) or may simply be soft tissue impaction as is fairly

common in third molars with not enough room to erupt.

• Impacted teeth are those that have failed to erupt and often remain buried in

the alveolar bone. Usually, some barrier to eruption will be seen on the X-ray

film. The 3rd molars and max canines are the most frequently impacted

teeth, followed by premolars and supernumerary teeth.

Tooth Wear Attrition

normal wearing away of tooth structures incisally and occlusally

Abrasion

the wearing away of the tooth structire by mechanical means, toothbrushing, in the cervical third

erosion

loss of tooth structure by a non bacterial chemical process, teeth appear smooth and underlying dentin my be exposed

abfraction

stress induced cervical lesions from celnching. • Caused by repeated flex of the tooth from occlusal trama

• Lesion becomes enlarged from attrition, abrasion and erosion

• Usually posterior regions

Tooth Filing

is the reshaping of the teeth through the removal of a part of the tooth.

Oral Parafunctional habit

used to describe any abnormal behaviour or functioning of

the oral structures

Oral Parafunctional habits include

bruxism, clenching, excessive gum chewing, lip or fingernail biting,

thumbsucking

Bruxism

excessive teeth clenching or jaw grinding in movements other then chewing

bruxism Signs/Symptoms:

abfraction lesions, gingivsl recession, head aches, limited range of motion in the mandible, linea alba, pain, tmj disorders, tooth fracture, tooth wear, tooth sensitivity, attrition.

bruxism treatment

night gaurdes, massages, botox