Dental Anomalies

Cards · 52

Anodontia

Total congenital absence of all primary and permanent teeth; rare, commonly associated with severe hereditary ectodermal dysplasia.

Hypodontia

Congenital absence of one to five teeth (excluding third molars); commonly affects maxillary lateral incisors and second premolars; caused by genetic mutations (e.g., MSX1, PAX9).

Oligodontia

Congenital absence of six or more teeth (excluding third molars); marked by reduced alveolar development; linked to systemic syndromes and gene defects.

Hyperdontia

Presence of supernumerary teeth beyond the normal complement; leads to impaction or crowding; caused by dental lamina hyperactivity or conditions like cleidocranial dysplasia.

Mesiodens

Supernumerary tooth located at the maxillary midline between central incisors; often conical or inverted; results from localized hyperactivity of dental lamina.

Paramolar

Small, rudimentary supernumerary molar located buccally or lingually to normal molars; caused by localized dental lamina proliferation.

Distomolar

Supernumerary tooth situated distal to the third molar; often microdontic; caused by continued proliferation of the posterior dental lamina.

Natal and Neonatal Teeth

Teeth present at birth (natal) or erupting within 30 days (neonatal); mostly mandibular primary incisors; caused by superficial tooth germ positioning or syndromes.

Microdontia

Teeth that are abnormally smaller than normal; most commonly localized to maxillary lateral incisors (peg laterals); caused by genetic factors or hypopituitarism.

Macrodontia

Teeth that are abnormally larger than normal; can cause severe crowding; caused by localized vascular abnormalities, pituitary gigantism, or facial hemihyperplasia.

Gemination

Single tooth germ attempts to divide, resulting in a bifid crown with a single root and root canal; normal tooth count remains; caused by trauma or genetic factors.

Fusion

Union of two normally separate tooth germs, resulting in a wide crown with two separate pulp chambers or root canals; tooth count is reduced by one; caused by physical pressure.

Concrescence

Union of two fully formed adjacent teeth along their cementum only; commonly involves maxillary molars; caused by trauma, crowding, or local chronic inflammation.

Dilaceration

Sharp bend or curve in the root or crown of a tooth; complicates extraction and endodontics; caused by mechanical trauma or cyst pressure during root development.

Dens Invaginatus

Infolding of enamel and dentin into the pulp chamber ('dens in dente'); predominantly affects maxillary lateral incisors; caused by localized invagination of the enamel organ.

Dens Evaginatus

Accessory enamel tubercle projecting from the occlusal surface, usually of mandibular premolars; prone to pulp exposure; caused by evagination of inner enamel epithelium.

Talon Cusp

Well-defined accessory cusp projecting from the cingulum of an anterior tooth; contains pulp tissue; caused by focal hyperplasia of the dental papilla and enamel organ.

Taurodontism

Enlarged pulp chamber with an apically displaced pulpal floor and shortened roots; seen in molars; caused by failure of Hertwig's epithelial root sheath to invaginate at the proper level.

Enamel Pearl

Small ectopic spherical droplet of enamel on the root surface, usually near the furcation of permanent molars; caused by localized differentiation of Hertwig's sheath.

Cusp of Carabelli

Accessory cusp located on the mesiolingual cusp of maxillary first molars; considered a benign, normal anatomical variation with high genetic heritability.

Shovel-Shaped Incisors

Incisors with prominent marginal ridges creating a concave lingual fossa; high racial prevalence in Asian and Native American populations; hereditary variation.

Supernumerary Roots

Development of more roots than normal for a tooth type, common in permanent mandibular canines and molars; caused by aberrant Hertwig's root sheath folding.

Amelogenesis Imperfecta: Hypoplastic Type

Deficient quantity of enamel with normal hardness; presents with pitted, grooved, or thin crowns; caused by mutations in enamel matrix genes like AMELX or ENAM.

Amelogenesis Imperfecta: Hypocalcified Type

Normal thickness of enamel that is poorly mineralized, soft, and easily abraded; crowns appear yellow-brown; caused by matrix calcification defects (e.g., FAM83H).

Amelogenesis Imperfecta: Hypomaturation Type

Enamel with normal thickness but reduced mineral content; displays mottled, opaque, or 'snow-capped' appearance; caused by defective crystal maturation (e.g., MMP20, KLK4).

Dentinogenesis Imperfecta: Type I

Opalescent blue-gray teeth with bulbous crowns and obliterated pulps; associated with systemic osteogenesis imperfecta; caused by COL1A1 or COL1A2 mutations.

Dentinogenesis Imperfecta: Type II

Hereditary opalescent dentin occurring without osteogenesis imperfecta; features rapid attrition and obliterated pulps; caused by DSPP gene mutations.

Dentinogenesis Imperfecta: Type III

Rare 'Brandywine' isolate showing multiple pulp exposures, bell-shaped crowns, and enlarged shell-like pulps; caused by DSPP mutations.

Dentin Dysplasia: Type I

Radicular type; normal crown appearance with short, blunt, or absent roots and obliterated pulp chambers; caused by defect in Hertwig's epithelial root sheath.

Dentin Dysplasia: Type II

Coronal type; primary teeth appear opalescent; permanent teeth have normal crowns but 'thistle-tube' pulp chambers with pulp stones; linked to DSPP mutations.

Regional Odontodysplasia

'Ghost teeth' showing marked hypocalcified enamel and dentin with wide pulps confined to one quadrant; caused by localized vascular or developmental ischemia.

Enamel Hypoplasia

Quantitative defect producing pits, grooves, or thin areas of enamel; caused by insults to ameloblasts during matrix formation such as trauma, infection, or malnutrition.

Turner's Hypoplasia

Focal enamel hypoplasia on a permanent tooth, usually a premolar; caused by periapical infection or mechanical intrusion trauma of the overlying primary tooth.

Dental Fluorosis

Hypomineralization ranging from white flecks to confluent brown staining and pitting; caused by chronic ingestion of excessive fluoride during amelogenesis.

Tetracycline Staining

Intrinsic yellow, gray, or brown fluorescent banding within dentin; caused by incorporation of tetracycline antibiotics into calcifying dental tissues during development.

Hutchinson's Incisors

Screwdriver-shaped permanent central incisors with notched incisal edges; classic sign of congenital syphilis caused by Treponema pallidum infection.

Mulberry Molars

Permanent first molars with multiple poorly formed, globular cusps resembling berries; associated with congenital syphilis.

Erythroblastosis Fetalis Pigmentation

Green, blue, or brownish intrinsic staining of primary teeth; caused by Rh incompatibility leading to bilirubin deposition in developing dental tissues.

Congenital Porphyria Discoloration

Red-brown intrinsic tooth discoloration that fluoresces red under UV light; caused by an inborn error of porphyrin metabolism and pigment deposition.

Attrition

Mechanical wear of occlusal and incisal tooth structure resulting from physiologic tooth-to-tooth contact; accelerated by bruxism or coarse diets.

Abrasion

Pathologic wearing of hard tooth tissue caused by mechanical friction from foreign objects (e.g., hard toothbrushes, pipe stems, biting nails).

Abfraction

Wedge-shaped cervical tooth loss caused by eccentric biomechanical occlusal loading and tooth flexure, weakening enamel and dentin at the fulcrum.

Erosion

Irreversible loss of hard tooth structure due to chemical dissolution by non-bacterial acids (e.g., gastroesophageal reflux, frequent citrus consumption, bulimia).

Internal Resorption

Symmetrical oval expansion of the pulp cavity outwards; can show a 'pink spot of Mummery'; caused by pulpal inflammatory response or trauma activating odontoclasts.

External Resorption

Pathologic loss of root surface starting from cementum towards dentin; caused by periapical inflammation, orthodontic forces, impacted teeth, or trauma.

Tooth Ankylosis

Solid fusion of cementum or dentin directly to alveolar bone, obliterating the PDL space; produces a dull percussion sound; caused by trauma or localized infection.

Tooth Transposition

Positional interchange of two adjacent teeth within the dental arch; most commonly canine and first premolar; caused by genetic factors or ectopic eruption.

Tooth Impaction

Failure of a tooth to erupt due to physical barrier in the eruption path or improper angulation; most common in third molars and maxillary canines; caused by crowding.

Ectopic Eruption

Tooth erupting out of its normal anatomical position, commonly maxillary first molars resorption-locking adjacent primary teeth; caused by arch length deficiency.

Premature Eruption

Teeth erupting significantly earlier than expected; seen in endocrinopathies like hyperthyroidism or due to early loss of overlying primary teeth.

Delayed Eruption

Teeth failing to emerge within typical age ranges; caused by hypothyroidism, hypopituitarism, rickets, or thick fibrous gingiva.

Hypercementosis

Excessive non-neoplastic deposition of secondary cementum along the root; complicates extraction; caused by chronic inflammation, Paget's disease, or occlusal trauma.