Effect of Nocturnally Worn Occlusal Splints on Condylar Position

Patients with craniomandibular dysfunction may experience changes in mandibular position over time when wearing occlusal splints continuously throughout the day and night. The aim of this study was to investigate whether similar changes can also be observed in healthy individuals who wear such splints exclusively at night.

The study included 13 healthy participants who were provided with maxillary stabilization splints worn only during night-time. Clinical evaluations were conducted after exactly 7 days, and the total study duration was 3 weeks. The maximal intercuspal position (MIP) as well as the centric condylar position (CR) were recorded in the condylar region of a measuring articulator. Additionally, the centric condylar position with the splint in place was determined several times using a thermoplastic registration material. The magnitude and direction of the positional differences were compared.

The differences in mandibular position between centric condylar position (CR, wax registration records) and maximal intercuspal position (MIP, no interdental records) measured 0.74 ± 0.35 mm at the first and 0.74 ± 0.37 mm at the final session. The corresponding distances between all CR records obtained with the splints and MIP were 0.82 ± 0.39 mm.

Within the investigated sample, night-time use of stabilization splints did not result in any change in mandibular position. A secondary finding was that occlusal adjustments were required during splint delivery, despite the use of facebows and registration procedures.