Changes in condylar position using different types of splints with and without a chinstrap: a case-control study.

Area of Science:

• Dental biomechanics
• Orthodontics
• Temporomandibular joint (TMJ) research

Background:

• Mandibular advancement devices (MADs) are used to treat sleep apnea and other conditions.
• Understanding the biomechanical effects of different splint designs is crucial for optimizing treatment outcomes.
• Previous research has not fully quantified the condylar position changes induced by various splint features.

Purpose of the Study:

• To analyze and quantify the mechanical effects of different splint designs on condyle position.
• To investigate the influence of pivot height and chinstrap use on vertical, sagittal, and horizontal condyle displacement.
• To compare stabilization splints with uni- or bilateral pivot splints.

Main Methods:

• Case-control study involving 40 asymptomatic volunteers.
• Utilized ultrasound-based jaw-tracking system for electronic condylar position analysis (0.1 mm accuracy).
• Tested stabilization splints and pivot splints (0.6 mm or 1.9 mm height) with and without a chinstrap (5N per side).

Main Results:

• Splint design (stabilization vs. pivot) did not significantly affect condyle position.
• Pivot height significantly influenced condyle position across all axes (p ≤ 0.02).
• Chinstrap use significantly impacted horizontal (X-axis) and vertical (Y-axis) condyle position (p ≤ 0.03), leading to less anterior and more inferior displacement (p ≤ 0.003).

Conclusions:

• Pivot splints alone do not significantly alter condyle position.
• The combination of pivot splints and a chinstrap produces a significant distractive effect on the condyles.
• Chinstrap use is a critical factor in modulating the biomechanical outcomes of pivot splints.