Radiology for 3rd Grade

Radiology for 3rd Grade

• This presentation covers dental anomalies, categorized by number, structure, size, shape, and position.

Radiographic Appearance of Dental Anomalies

• Developmental anomalies affect teeth and facial structures.
• Diagnoses rely on both clinical and radiographic examinations.
• Anomalies of the teeth include variations in number, structure, size, shape, and position.
• Skeletal anomalies are also considered in diagnosis.

Abnormalities in Number

• Hypodontia: Missing teeth due to developmental failure, often associated with ectodermal dysplasia.
• Hyperdontia: Extra teeth, classified by position (mesiodens, paramolar, distomolar). Fourth and fifth molars behind the third molars are also considered supernumerary teeth. Hyperdontia may be connected to Cleidocranial Dysplasia.

Abnormalities in Structure

• Genetic defects:

  • Amelogenesis Imperfecta: Enamel formation defects, leading to abnormal enamel morphology with normal dentin and pulp.
  • Dentinogenesis Imperfecta: Defective dentin formation causing pulp obliteration and short, blunt roots.
  • Odontodysplasia (ghost teeth): Reduced radiodensity, with very thin enamel and dentin, and large pulp chambers.

• Acquired defects:

  • Turner hypoplasia: Enamel defects in permanent teeth due to periapical inflammatory disease of the overlying deciduous tooth.
  • Congenital Syphilis: Dental hypoplasia resulting from infection with syphilis, affecting permanent incisors (Hutchinson's teeth) and first molars (mulberry molars).

Abnormalities in Size

• Macrodontia: Abnormally large teeth (megadontia or megalodontia).
• Microdontia: Abnormally small teeth. Can be generalized (affecting all teeth) or localized (affecting a few teeth), or limited to a single tooth and often involves upper incisors and third molars.

Abnormalities in Shape

• Fusion: Two teeth joined together into a single crown.
• Gemination: Two separate teeth arising from a single tooth germ, sharing a single root with two crowns.
• Dilaceration: Deviation or bend in the tooth's root or crown.
• Dens invaginatus: Tooth development abnormality, with invagination of the enamel organ into the dental papilla.
• Enamel pearl: Small spherical enamel masses found near the roots of molars.
• Taurodontism: Enlarged pulp chamber and roots in molars, moving the pulp & the tooth furcation apically.
• Talon cusp: Accessory cusp structure projecting from the cingulum area of maxillary or mandibular teeth.

Skeletal Anomalies

• Cleft lip and palate
• Micrognathia
• Macrognathia
• Torus palatines
• Torus mandibularis