Clinical study of double occlusal splints combined with manual reduction for the treatment of anterior disc displacement without reduction: a retrospective study

Objectives: Some patients with anterior disc displacement without reduction (ADDWoR) experience restricted mouth opening after manual reduction. This study aimed to compare the therapeutic efficacy of modified double occlusal splints with traditional anterior repositioning splints (ARS) in treating ADDWoR, to identify a simple, effective, and stable clinical approach. Materials and Methods: A total of 107 patients were enrolled in this single-center retrospective study. Those using double occlusal splints after successful manual reduction were assigned to observation groups (A, B). Clinical indicators included pain visual analogue score (VAS), maximum mouth opening (MMO), craniomandibular index (CMI), dysfunction index (DI), palpation index (PI), and overall efficacy. Results: At one month post-treatment, groups A and B showed significant improvements in VAS, MMO, CMI, and DI compared to control groups C and D ( P < 0.05). At three and six months, group A had significantly lower CMI and DI than group C, with no significant VAS or MMO difference. Group B showed greater improvement than group D across all parameters ( P < 0.05). Magnetic resonance imaging (MRI) confirmed higher disc reduction rates in the observation groups. Clinical efficacy was 89.3% in experimental groups versus 74.5% in control groups (c ² = 3.990, P < 0.05). Conclusion: Double occlusal splints demonstrated superior stabilization following early manual repositioning and improved structural outcomes compared to ARS. These findings support their clinical value as a treatment option for ADDWoR. Clinical Relevance: This study demonstrates that modified double occlusal splints provide more effective and stable outcomes than traditional anterior repositioning splints, particularly after early manual disc repositioning. The findings offer clinicians a simplified, non-invasive treatment strategy that enhances long-term joint stabilization and functional recovery in ADDWoR patients.