Application of fully digital occlusal splints in painful temporomandibular disorders: a randomized controlled clinical study

OBJECTIVE: To evaluate the clinical efficacy of digital occlusal splints in alleviating pain and dysfunction in patients with temporomandibular disorders (TMD) and underlying mechanisms. METHODS: TMD patients were enrolled and divided into digital and conventional occlusal splint groups (n = 66/group). Clinical outcomes, including visual analog scale (VAS) scores and temporomandibular function indices [Craniomandibular Index (CMI), Dysfunction Index (DI), Palpation Index (PI)], were assessed pre- and post-treatment. Cone-beam computed tomography (CBCT) was used to analyze condylar positional changes and joint space adaptation, while quantitative polymerase chain reaction and enzyme-linked immunosorbent assay measured serum levels of inflammatory markers. Correlations between clinical, structural, and biochemical parameters were examined. RESULTS: Both groups exhibited significant post-treatment reductions in VAS scores, CMI, DI, and PI (P < 0.05), with the digital group demonstrating superior improvements in VAS, PI, and CMI compared to controls (P < 0.001). CBCT revealed favorable structural adaptations in both groups, though the digital group showed greater enhancements in glenoid fossa depth and medial joint space (P < 0.05). Biochemical analysis confirmed significant decreases in tumor necrosis factor-α (TNF-α), fibroblast growth factor receptor 3 (FGFR3), and nitric oxide synthase 2 (NOS2) levels, with additional reductions in nerve growth factor (NGF) and human leukocyte antigen B (HLA-B) observed exclusively in the digital group (P < 0.05). CONCLUSION: Digital occlusal splints effectively mitigate TMD-related pain and dysfunction, likely through synergistic mechanisms involving occlusal stabilization, joint structural optimization, and inflammatory modulation. This technology represents a promising precision-based approach for personalized TMD management.