Antegonial notch

Anatomical feature of the mandible

The antegonial notch is a distinct anatomical feature of the mandible, or lower jawbone, characterized by a depression or notch located on the inferior border of the mandible, anterior to the angle of the mandible. This feature is of particular interest in the fields of dentistry, orthodontics, and maxillofacial surgery due to its implications in jaw development and alignment.

Anatomy

Mandible showing antegonial notch

The antegonial notch is situated on the lower border of the mandible, just in front of the gonial angle, which is the angle formed by the junction of the posterior and inferior borders of the mandible. The depth and prominence of the antegonial notch can vary significantly among individuals and can be influenced by genetic and environmental factors.

Development

The development of the antegonial notch is closely related to the growth patterns of the mandible. During childhood and adolescence, the mandible undergoes significant growth and remodeling, which can affect the size and shape of the antegonial notch. The notch is typically more pronounced in individuals with certain growth patterns, such as those with a retrognathic mandible, where the lower jaw is positioned further back relative to the upper jaw.

Clinical Significance

The antegonial notch is an important landmark in various clinical assessments and procedures. In orthodontics, the depth of the antegonial notch can be used as an indicator of mandibular growth direction and potential growth abnormalities. A deep antegonial notch may suggest a vertical growth pattern, which can be associated with certain malocclusions and facial asymmetries.

In maxillofacial surgery, the antegonial notch serves as a reference point for surgical planning and reconstruction of the mandible. Understanding the anatomy and variations of the antegonial notch is crucial for achieving optimal surgical outcomes.

Associated Conditions

Certain conditions and syndromes can affect the development and appearance of the antegonial notch. For example, Pierre Robin sequence and Treacher Collins syndrome are congenital conditions that can result in mandibular hypoplasia, leading to a more pronounced antegonial notch.

Related Pages

• Mandible
• Orthodontics
• Maxillofacial surgery
• Pierre Robin sequence
• Treacher Collins syndrome