Chewing pattern analysis in TMD patients with unilateral and bilateral internal derangement

Area of Science:

• Biomechanical analysis of mastication
• Temporomandibular joint (TMJ) disorders
• Internal derangement biomechanics

Background:

• Temporomandibular disorder (TMD) affects chewing function.
• Internal derangement of the TMJ can impact masticatory movements.
• Understanding chewing patterns is crucial for diagnosing and managing TMJ dysfunction.

Purpose of the Study:

• To analyze the envelope of motion and velocity during chewing in TMD patients.
• To compare chewing patterns between unilateral and bilateral internal derangement of the TMJ.
• To differentiate chewing characteristics in TMD patients versus healthy controls.

Main Methods:

• Analysis of chewing envelope of motion and velocity.
• Evaluation of chewing patterns in frontal and sagittal planes.
• Study included 103 TMD patients with unilateral internal derangement, 42 with bilateral internal derangement, and 10 normal subjects.

Main Results:

• Bilateral internal derangement patients showed significantly restricted range of motion and reduced chewing velocity compared to unilateral cases and controls.
• Unilateral internal derangement patients displayed specific chewing patterns, while bilateral cases lacked distinct patterns.
• Opening and closing patterns without obvious peak velocity were more frequent in bilateral internal derangement patients.

Conclusions:

• Bilateral internal derangement of the TMJ leads to more severe chewing dysfunction than unilateral internal derangement.
• Chewing pattern analysis can help differentiate between types of internal derangement.
• Reduced chewing velocity and range of motion are key indicators of bilateral TMJ internal derangement.