A retrospective evaluation of the clinical efficacy of occlusal splint therapy combined with manual therapy in patients with anterior disc displacement without reduction

Background: The study aimed to retrospectively evaluate the clinical efficacy of a computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated occlusal splint combined with manual therapy in patients diagnosed with anterior disc displacement without reduction (ADDwoR) of the temporomandibular joint (TMJ). Methods: The medical records of 65 adult patients with ADDwoR, treated between March 2022 and March 2023, were reviewed and allocated into three treatment groups based on the interventions they received, namely, occlusal splint therapy alone (n = 22), occlusal splint therapy combined with manual therapy (n = 22), or health education alone (n = 21). All participants received standardized health education. Clinical outcomes, including Maximum Mouth Opening (MMO), Visual Analog Scale (VAS) for pain, and the Mandibular Functional Impairment Questionnaire (MFIQ), were assessed at baseline and one and three months post-treatment by blinded evaluators. Statistical analyses were conducted using Python with Welch’s analysis of variance (ANOVA) and repeated measures ANOVA, and significance was set at p < 0.05. Results: The baseline demographic and clinical characteristics were similar among the three groups (all p > 0.05). At the three-month follow-up, no significant changes were observed in the health education group (p > 0.05). In contrast, both the occlusal splint group and the combined treatment group demonstrated significant improvements in MMO, VAS and MFIQ scores at both one and three months compared to baseline (all p < 0.05). Moreover, the combined treatment group showed significantly greater improvement in all measured outcomes than the splint-only group at each follow-up, with the most substantial differences observed at the three-month follow-up (all p < 0.05). Conclusions: This short-term non-randomized retrospective study suggests that combining CAD/CAM-fabricated occlusal splint therapy with manual therapy yielded superior pain relief and functional improvement compared to splint therapy alone or health education in patients with ADDwoR.

Anterior disc displacement without reduction (ADDwoR); Temporomandibular disorders (TMD); Occlusal splint (CAD/CAM); Manual therapy; Maximum mouth opening (MMO); Visual analog scale (VAS); Mandibular functional impairment questionnaire (MFIQ)

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