Condylar trauma and facial asymmetry: an experimental study

Area of Science:

• Oral and Maxillofacial Surgery
• Orthodontics
• Veterinary Medicine

Background:

• Temporomandibular joint (TMJ) ankylosis can result from trauma.
• Facial asymmetry is a potential consequence of TMJ disorders.
• Understanding the role of trauma in TMJ ankylosis is crucial for effective treatment.

Purpose of the Study:

• To investigate the effects of surgical intracapsular condylar fractures and prolonged intermaxillary fixation on facial symmetry and TMJ ankylosis in young monkeys.
• To assess the functional impact on jaw movement following these procedures.

Main Methods:

• Young monkeys underwent surgical intracapsular condylar fractures.
• Prolonged intermaxillary fixation was applied to induce facial asymmetry and TMJ ankylosis.
• Implanted head positioners and metallic bone markers tracked facial asymmetry.
• Jaw opening capabilities and condylar movement were evaluated.

Main Results:

• All animals recovered full vertical jaw opening capabilities.
• The procedures had no discernible negative functional impact on jaw movement.
• A slight limitation in the translation of damaged condyles was observed.
• No significant TMJ ankylosis or substantial jaw movement limitation was induced.

Conclusions:

• Trauma followed by long-term fixation did not promote ankylosis or significant jaw movement limitation in this model.
• Factors complicating existing trauma may play a more significant role in the etiology of TMJ ankylosis.