Dental Anatomy Lecture 12: Dental Anomolies

What are the types of anomalies?

1. Congenital

2. Environmental

When are congenital anomalies present?

At birth or during tooth development

What are the possible causes of congenital anomalies?

1. Genetic

2. Disturbance in odontogenesis

When do environmental anomalies occur?

After tooth formation

What are the possible causes of environmental anomalies?

1. Trauma

2. Infection

3. Medication

What are the five tooth features that anomalies can affect?

1. Shape/Size

2. Root formation

3. Number

4. Structure

5. Chronology

What is the anomaly where the teeth are abnormally small?

Microdontia

Which teeth does microdontia usually affect?

1. Maxillary Lateral Incisors

2. Third Molars

What is the anomaly where the teeth are abnormally large?

Macrodontia

What condition is often associated with macrodontia?

Pituitary Gigantism (Excessive growth)

What are the treatments for microdontia?

1. Veneers/Crowns

2. Bonding

What are the treatments for macrodontia?

1. Reshaping

2. Extraction

What feature of the teeth do fusion and gemination affect?

Shape/Size

What is the anomaly that results in the union of two adjacent teeth, resulting in one large tooth

Fusion

What features are shown in a tooth that was fused?

1. Large crown

2. Two distinct pulp chambers

What is the anomaly where a single tooth germ divides into a bifid crown?

Gemination

What features are shown in a tooth that was geminated?

1. Single root and pulp chamber

2. Two crowns

What are the internal anomalies of tooth shape?

1. Dens Invaginatus

2. Dens Evaginatus

3. Taurodontism

What anomaly is the infolding of enamel and dentin into the pulp chamber?

Dens Invaginatus (Dens in Dente)

Which anomaly causes a "tooth within a tooth" radiographic appearance?

Dens Invaginatus (Dens in Dente)

Which anomaly causes a deep pit/groove in the cervical area?

Dens Invaginatus (Dens in Dente)

What are teeth with Dens Invaginatus highly susceptible to?

1. Caries

2. Pulp Necrosis

What anomaly causes out-pouching of enamel and dentin?

Dens Evaginatus

Which anomaly causes an extra cusp or tubercle, often on premolars?

Dens Evaginatus

Which anomaly causes the enlargement or elongation of the pulp chamber?

Taurodontism

What are the radiographic appearances of taurodontism?

1. Rectangular pulp chamber

2. Pulp chamber with low furcation area

3. Short roots

Taurodontism only affects _______

Permanent teeth

What are the external abnormalities of tooth shape?

1. Hutchinson's Teeth

2. Carabelli's Traits

3. Enamel Pearls

4. Talon Cusps

Which anomaly is the result of congenital syphilis?

Hutchinson's Teeth

Which anomaly results in Mulberry molars?

Hutchinson's Teeth

Which anomaly may have notched incisors?

Hutchinson's Teeth

Which anomaly results in accessory cusps or tubercles on teeth?

Carabelli's Traits

Which anomaly is the most common in the furcation of maxillary molars?

Enamel Pearls

What difficulty may enamel pearls cause in clinical environements?

Difficulty to clean around

Which anomaly causes a small enamel projection in cingulum area of anterior?

Talon Cusps

What are the possible results of Talon Cusps?

1. Pulp horn

2. Occlusal interferences

Which anomaly is a severe root bend?

Dilacerations (Flexion)

What are the degrees the root may be bent in dilacerations?

45 - 90 degrees

What are the causes of dilacerations?

Trauma/crowding during development or eruption

What anomaly is the separation of root due to trauma during root formation?

Segmented Roots

Which anomaly has normal crowns with very short roots?

Dwarfed (Short) Roots

What are the potential causes of Dwarfed (Short) Roots?

1. Hereditary

2. Rapid treatment

Which single rooted teeth are most affected by accessory roots?

Mandibular canines and premolars

Which multi rooted teeth are most affected by accessory roots?

Third Molars

Which anomaly is the joining of two teeth at roots through cementum?

Concrescence

Unlike fusion, what is the only thing involved for Concrescence?

Cementum

When does Concrescence occur?

After eruption

Which anomaly is the excess cementum around tooth after eruption?

Hypercementosis

What are the possible causes of Hypercementosis?

1. Idiopathic

2. Local/systemic factors

What are the anomalies where teeth are missing congenitally?

1. Hypodontia

2. Oligodontia

3. Anodontia

How many teeth may be missing for hypodontia?

1 - 5

How many teeth may be missing for oligodontia?

6+

How many teeth may be missing for anodontia?

All teeth

What is the cause of congenital missing teeth?

Disturbance of dental lamina during bud formation

What are the teeth most affected by hypodontia?

1. Third molars

2. Maxillary lateral incisors

3. Mandibular second premolars

What are the clinical appearances of hypodontia?

1. Gaps in dentition

2. Peg-shaped maxillary laterals

What are the radiographic appearances of hypodontia?

Absence of tooth germ in jaw

What are the treatments for hypodontia?

1. Orthodontics

2. Implants

3. Bridges

Which anomaly is the presence of one or more extra teeth?

Hyperdontia (Supernumerary Teeth)

What is the most common supernumerary tooth?

Mesiodens

Where are mesiodens located?

Between maxillary central incisors

Which tooth has the most common mandibular extra teeth near it?

Mandibular second premolar

90% of supernumerary teeth occur in the ________

Maxilla

What is the common treatment of supernumerary teeth?

Extraction

What is the anomaly where a group of inherited conditions affects enamel formation?

Amelogenesis Imperfecta

What are the clinical features of Amelogenesis Imperfecta?

1. Hypoplastic

2. Hypomaturation

3. Hypocalcified

What describes pitted, grooved, or thin enamel?

Hypoplastic Type

What describes normal thickness but mottled, opaque, and soft enamel?

Hypomaturation Type

What describes normal shape but soft, cheesy enamel that chips easily?

Hypocalcified Type

What is the radiographic feature of Amelogenesis Imperfecta?

Enamel appears much less opaque

Which anomaly is an inherited condition affecting dentin formation?

Dentinogenesis Imperfecta

What are the clinical features of Dentinogenesis Imperfecta?

1. Blue/Brownish appearance of teeth

2. Enamel flakes off to expose dentin

What are the radiographic features of Dentinogenesis Imperfecta?

1. Destroyed pulp chambers and root canals (Type 1/2)

2. Enlarged pulp (Type 3)

3. Short roots

4. Bulbous crowns

What are the treatments for Dentinogenesis Imperfecta?

1. Full coverage crowns

2. Root canals

3. Extractions

What are the chronological anomalies?

1. Neonatal teeth

2. Early/delayed eruption

When do neonatal teeth develop?

First month of life

Which anomaly is a misplaced tooth bud that develops in the wrong spot?

Transposition

Which acquired anomaly is a permanent tooth with a localized area of hypoplasia or discoloration?

Turner's Tooth

Which acquired anomalies cause discoloration?

1. Tetracycline Staining

2. Dental Fluorosis

What is the cause of tetracycline staining?

Ingestion of tetracycline antibiotics during tooth development

Which anomaly looks like horizontal gray, brown, or yellow bands that fluoresce under UV light?

Tetracycline Staining

What is the cause of dental fluorosis?

Excessive fluoride intake during tooth development

Which anomaly looks like white flecks or mottled enamel?

Dental Fluorosis