RADIOGRAPHIC INTERPRETATION

OF DENTAL ANOMALIES

DRG. SHANTY CHAIRANI

CHANGES IN NUMBER OF TEETH

ANODONTIA Total anodontia: congenital absence of all

teeth Partial anodontia (hypodontia,

oligodontia): congenital absence of one or more teeth, usually a maxillary lateral incisor or mandibular bicuspid or a third molar tooth.

Total anodontia

Partial anodontia

SUPERNUMERARY TEETH Teeth in excess of the normal number Clinical Features:

90% in maxilla Single or multiple, impacted or erupted Mesiodens most common, paramolar,

distomolar Numerous supernumerary teeth are found

in such developmental disturbances as cleidocranial dysplasia, craniofacial dysostosis, mandibulofacial dysostosis.

Supernumerary Teeth

Supernumerary Teeth

SUPERNUMERARY ROOTS Extra roots; more than the expected

number. Clinical Features:  more common in

mandibular bicuspids and permanent molars from either arch

Radiographic Features: not always visible on a radiograph

Supernumerary Roots

MACRODONTIA One or more teeth that are larger than normal. Clinical Features:

 Generalized - all of the teeth are affected True generalized - all teeth in both arches larger

(pituitary gigantism)  Relative generalized - small jaw size relative to

the teeth makes teeth seem larger crowding of teeth)

  Localized - isolated teeth affected Only occasionally found and is often associated

with hemifacial hypertrophy Radiographic Feature: large tooth

CHANGES IN SIZE OF TEETH

Macrodontia

MICRODONTIA One or more teeth that are smaller than normal. Clinical Features:

Generalized - all of the teeth are affected True generalized - all teeth in both arches

smaller (pituitary dwarfism) Relative generalized - large jaw size relative

to the teeth makes teeth seem smaller; space between teeth)

Localized - one or two teeth affected, usually :maxillary lateral incisors (peg laterals), maxillary third molars

Often conically shaped Radiographic Feature: small tooth

Microdontia

GEMINATION Abnormally shaped crown that is extra wide due to the

development of two crowns from one tooth germ. Radiographic Feature : a tooth with a single root

canal and either a large crown or two crown.

FUSION An abnormally shaped tooth that may appear as an

extra wide crown, a normal crown with an extra root, or other combinations resulting from the union of two adjacent tooth germs by dentin during development.

Radiographic Feature : a tooth with two root canals and either a large crown or two crowns.

CHANGES IN SHAPE OF TEETH

Fusion

Gemination

CONCRESCENCE Union of the roots of two or more normal teeth

caused by confluence of their cemental surfaces.

DILACERATION A sharp bend or angulation of the root portion

of a tooth. Radiographic Features : abnormal angulation

anwhere along the length of the tooth

Concrescence Dilaceration

ENAMEL PEALR (ENAMELOMA) Ectopic nodular deposits of enamel that

primarily occur in the bifurcation or trifurcation areas on the roots of molars.

Radiographic Feature : usually found near the root furcations of single or multirooted teetH

Enamel Pearl (Enameloma)

DENS INVAGINATUS (DENS IN DENTE) Developmental anomaly in which a focal area of the

crown is folded inward (invaginated) for various distances.

When severe, this results in a conically shaped tooth with a small surface opening (dens in dente) that quickly becomes subject to caries, pulpitis, and periapical inflammation.

Clinical Features: Rare in primary teeth Most often permanent maxillary lateral incisors, central

incisors, proemolars, canines and molars Lingual surface may have pits

Radiographic Features: May resemble a tooth within a tooth Enlargement of the root Dilated invagination lined by enamel with the opening

of the invagination situated along the lateral aspect of the root

Dens in Dente (Dens Invaginatus)

DENS EVAGINATUS A developmental anomaly in which a focal

area of the crown projects outward and produces what appears as an extra cusp or an abnormal shape to existing cuspal arrangements.

Radiographic Feature : an extension of a dentin tubercle on the occlusal surface

TALON CUSP A form of supernumerary cusp which arises

from the cingulum portion of the tooth and extends to the incisal edge as a prominent projection of enamel that imparts a T shape

Clinical Features: Lingual of maxillary central incisors Arises from the cingulum portion of the tooth and

imparts a T shape Radiographic Feature: cusp contains a pulp

horn

Talon Cusp

TAURODONTIA An anomalous form of teeth that is

characterized by a clinical and anatomic crown of normal shape and size, an elongated body, and short roots with a longitudinally enlarged pulp chamber.

Radiographic features : The extension of the rectangular pulp

chamber into the elongated body of the tooth.

The shortened roots and root canals.

Taurodontia

AMELOGENESIS IMPERFECTA A spectrum of hereditary defects in the function of

ameloblasts and the mineralization of enamel matrix that results in teeth with multiple generalized abnormalities affecting the enamel layer only.

Clinical Features: Teeth vary in color from white opaque to yellow to

brown All teeth are affected, smaller and pitted Normal pulps and dentin but reduced enamel

Radiographic Features: The squarish shape of the crown, the relatively

thin layer of enamel, the low or absent cusps, and in some cases advanced abrasion.

CHANGES IN STRUCTURE OF TEETH

Amelogenesis Imperfecta

ENAMEL HYPOPLASIA A defect in tooth enamel that results in less

quantity of enamel than normal. Etiology : local, systemic or genetic factors  Clinical Features:

Pits, grooves, lines or larger areas of missing enamel surface

Reduction in enamel thickness Possible occlusal distortion, aesthetic problems,

sensitivvity Yelllowish or brownish discoloration May be localized or present on numerous teeth and all

or part of the surfaces of each affected tooth may be involved

Radiographic Feature : thin enamel

Enamel Hypoplasia

TURNER’S TOOTH Enamel hypoplasia of a single tooth, most

commonly one of the permanent maxillary incisors or a maxillary or mandibular premolar, resulting from local infection or trauma.

DENTINOGENESIS IMPERFECTA A hereditary defect consisting of opalescent

teeth composed of irregularly formed and undermineralized dentin that obliterates the coronal and root pulpal chambers.

Clinical Features: Opalescent teeth, undermineralized dentin Tooth fractures and chips away easily leads to

exposed dentin and functional attrition Radiographic Features:

Bulb-shaped crowns with constricted CEJ and thin roots

Multilocular May exhibit extremely large pulpal chambers;

obliterated

Dentinogenesis Imperfecta

DENTIN DYSPLASIA (ROOTLESS TOOTH) A hereditary defect in dentin formation in which

the coronal dentin and tooth color is normal; the root dentin is abnormal with a gnarled pattern and associated shortened and tapered roots.

Clinical Features: Normal eruption pattern Bluish in cervical region Types

Type I radicular dysplasia Normal crowns of regular or slightly amber

translucency Tendency toward complete obliteration of

pulp cavities Abnormal spaces between the teeth,

malignment, malpositon and severe mobility

Type II coronal dysplasia Semi-transparent opalescent primary teeth Normal appearance in the permanent teeth Incomplete obliteration of pulp cavities Pulp stones

Radiographic Features: Type I radicular dysplasia

Extremely short roots Obliterated pulp chambers and root canals before

eruption Periapical radiolucencies around the defective roots

  Type II coronal dysplasia Complete obliteration of pulp chambers and root

canals after eruption Pulp stones Absence of periapical radiolucencies

Dentin Dysplasia (Rootless Tooth)

REGIONAL ODONTODYSPLASIA (GHOST TEETH) A developmental disturbance of several adjacent teeth

in which the enamel and dentin are thin and irregular and fail to adequately mineralize; surrounding soft tissue is hyperplastic and contains focal accumulations of spherical calcifications and odontogenic rests.

Clinical Features: Not adequately mineralized; enamel and dentin are

soft, thin and irregular Associated with vascular nevi Usually unilateral Irregular surface contour with pitting and grooves on

small teeth, yellowish leathery brown in color Affects teeth sequentially in one or two quadrants,

affects both the primary and permanent dentitions, any tooth, maxilla anterior most common

Radiographic Features: Much less radiodensity Thin layers of enamel and dentin Indistinguishable CEJ Faint, fuzzy outline Ghost Teeth appearance Enlarged pulp chamber, enlarged canals

and  wide open apices Short and stubby roots Periapical abscess often present Widened PDL

Regional Odontodysplasia (Ghost Teeth)

ANOMALIES OF ERUPTION TEETH

PREMATURE ERUPTION Teeth present at birth (natal teeth) or shortly

after (neonatal teeth) ; eruption of permanent teeth after premature loss of preceding deciduous teeth.

DELAYED ERUPTION Appearance of deciduous or permanent teeth

relative to the normal age range. Radiographic Features:

Unerupted tooth Usually severe dental crowding in the affected

area

Delayed Eruption

IMPACTED TEETH Teeth continue to form within bone but fail to

erupt into the oral cavity because of a physical obstruction.

Radiographic Features: Completely impacted are totally surrounded by

bone Partially impacted tooth is partly in bone, partly in

soft tissue Embedded teeth are individual teeth that fail to

erupt for no apparent reason (term not used much)

Most common are mandibular and maxillary third molars, maxillary cuspids and supernumerary teeth.

Partial impaction

Complete impaction

REGRESSIVE CHANGES OF THE DENTITION

ATRITION Loss of tooth structure due to mechanical action

of mastication. Clinical Features:

Older adults Flattening of occlusal, incisal and proximal surfaces of

teeth

ABRASION Abnormal loss of tooth structure due to non-

masticatory physical friction. Clinical Features:

Loss of tooth structure at site of wear Sensitivity possible

ATRITION

ABRASION

ROOT RESORPTION Breakdown or destruction of root structure; loss

of root structure. The apex of the tooth appears shortened or

blunted and irregularly shaped.

EXTERNAL RESORPTION A loss of tooth structure that begins on the outer

surface and extends inward toward the pulp. Radiographic Features :

An irregularity in the normal contour of the root. May be uniform and may produce gradual blunting of

the root apex, or it may begin on the sides of the root

External Resorption

INTERNAL RESORPTION A form of tooth loss that begins within the pulpal

chambers of intact teeth, destroying dentin as it extends outward in a uniform pattern toward the tooth surfaces.

Clinical Features: Most are within the crown of the anterior incisors

and are idiopathic. Usually asymptomatic, lesion first detected by

appearance of a pink spot beneath the enamel surface

Radiographic Features : Fusiform enlargement of the pulpal chamber of one or more teeth that appears in either the crown or root pulpal chambers

Internal Resorption

PULP STONE Sperical calcification within the dental pulp lying

free or attached to the pulpal surface of the tooth.

Radiographic Features : radiopaque enlargements within the pulp chamber or canal

HYPERCEMENTOSIS Excessive deposit of cementum on root surface. Clinical Features:

Clinically undetectable Predonimantly adults

Radiographic Features: Root may have a larger circumference

than the upper portion, bulbous or pear-shaped

Most frequently premolar teeth