Anodontia and Tooth Development Overview

Anodontia

• Also known as Anodontia Vera.
• Characterized by congenital absence of teeth.
• Causes include failure of tooth bud development and can result in true anodontia.

Alterations in Size

• Micrdontia involves poorly developed teeth, presenting as peg-shaped and related to hypoplasia.
• Macrodontia is associated with megadontism and gigantism, indicating hyperplasia of teeth.
• Types include:
  • Total or Complete Anodontia: All teeth absent due to failure of dentition development, often linked to hereditary ectodermal dysplasia.
  • True Partial Anodontia: Absence of one or several teeth, might also be connected to hereditary factors.
  • Pseudoanodontia: Presence of multiple unerupted teeth due to impaction or delayed eruption.
  • Induced Anodontia: Results from tooth extraction.

Alterations in Number and Eruption

• Supernumerary teeth (Hyperdontia) represent an excessive number of teeth.
• Distinguished into true supernumerary (normal anatomy) and accessory/rudimentary (non-identifiable).
• Classification includes Mesiodens (most common) located between maxillary central incisors and Maxillary 4th Molar as the second most common.
• Impacted teeth commonly involve 3rd molars and maxillary canines, influenced by factors like lack of space due to crowding, rotation of tooth buds, and ankylosis.

Impaction Types and Symptoms

• Impacted teeth can be classified into:
  • Partial
  • Complete
  • Multiple
• Symptoms of impaction often include pericoronitis, characterized by inflammation of the gingiva covering the tooth.

Anomalies in Crown

• Fusion occurs when two tooth buds merge, typically in mandibular anterior teeth.
• Leong’s Premolar or Dens Evaginatus features an anomalous tubercle on premolars and can expose accessory pulp horns, often due to invaginatus or extrusion of the inner dental epithelium.
• Dens Invaginatus or Dens en Dente refers to a "tooth within a tooth" with exaggerated lingual pits and associated forms.
• Hypercementosis entails an overgrowth of cementum.

Supernumerary Roots and Defects of Enamel

• Supernumerary roots indicate an excess in root number.
• Amelogenesis imperfecta, also known as hereditary enamel hypoplasia, results from protein malfunction during enamel formation.

Clinical Features of Amelogenesis Imperfecta

• Symptoms include abnormal tooth coloration (yellow, brown, gray), thin or soft enamel, increased susceptibility to cavities, and hypersensitivity to temperature changes.

Anomalies in Roots

• Concrescence arises when two normally separated teeth fuse at the cementum level, commonly found in maxillary 2nd and 3rd molars.
• Etiological factors for both root anomalies and enamel defects include trauma, overcrowding, and systemic influences such as rickets.

This quiz explores the concepts of anodontia, including its types, causes, and associated conditions. It also covers alterations in tooth size and number, providing insights into dental anomalies like microdontia and hyperdontia. Test your knowledge on these important aspects of dental development and terminology.