Evaluation of temporomandibular joint function after orthognathic surgery using a jaw tracker

Area of Science:

• Biomedical Engineering
• Oral and Maxillofacial Surgery
• Orthodontics

Background:

• Temporomandibular joint (TMJ) dysfunction affects 20-25% of the general population, with 10-15% experiencing pain.
• Orthognathic surgery aims to correct jaw discrepancies but may impact TMJ function.
• Current evaluation methods for post-orthognathic surgery TMJ function are limited.

Purpose of the Study:

• To evaluate temporomandibular joint (TMJ) function after orthognathic surgery using four-dimensional (4D) jaw tracking.
• To compare TMJ function and clinical symptoms between orthognathic surgery patients and a control group.
• To investigate the utility of 4D jaw tracking in assessing subtle changes in TMJ biomechanics.

Main Methods:

• A cohort of 16 orthognathic surgery patients and 17 controls were assessed.
• Four-dimensional jaw tracking was performed using the SiCAT JMT device.
• TMJ function, clinical signs, and subjective symptoms were evaluated via questionnaires and device data.

Main Results:

• No significant millimetric differences in jaw movements were observed between the surgery and control groups.
• Subjective reports of pain, clicking, crepitation, locking, stiffness, headaches, and migraines showed no significant differences.
• A significant difference was found in the occurrence of joint popping between the orthognathic surgery and control groups.

Conclusions:

• Four-dimensional jaw tracking did not reveal significant differences in overall jaw function post-orthognathic surgery.
• Despite objective findings, subjective clinical symptoms were present in some patients.
• Joint popping may indicate subtle TMJ alterations following orthognathic surgery that warrant further investigation.