Is there a superiority between arthrocentesis and stabilizing occlusal splint for the treatment of anterior disc displacement with reduction and intermittent block and anterior disc displacement without reduction in TMJ? Randomized clinical trial.

INTRODUCTION: Anterior displacement of the temporomandibular joint (TMJ) disc is a disorder in which the articular disc is dislocated from its correct position relative to the mandibular condyle and mandibular fossa. Traditionally, the initial treatment of disc displacements involves various conservative measures, including the use of a stabilizing interocclusal splint. However, in cases where there is associated limited mouth opening, as in the case of anterior disc displacement with reduction and intermittent block (ADDwRIB), and anterior disc displacement without reduction (ADDw/oR), arthrocentesis has been suggested as another modality of initial treatment due to its faster effect in preventing disease progression to a more advanced stage, as well as reducing the chances of pain chronification and central sensitization. OBJECTIVES: This study aimed to analyze whether there is a preponderance in efficacy between treatments with a stabilizing interocclusal splint or arthrocentesis in these patients. METHODS: A randomized, prospective, longitudinal clinical trial was conducted. The sample was obtained by convenience, between June 2021 and January 2023. Twenty-four patients with diagnoses of ADDwRIB and ADDw/oR were included. The diagnosis and clinical evaluations followed the DC/TMD criteria, and TMJ MRI was performed. Patients were randomly allocated to 2 treatment groups. Group 1 (n = 13): stabilizing interocclusal splint. Group 2 (n = 11): arthrocentesis. Patients were evaluated after 1, 2, 3, and 6 months for clinical parameters of pain, functionality, and psychosocial status. RESULTS: Both treatments were effective in reducing pain levels, with no statistically significant differences. Group 1 showed significantly greater mouth-opening levels compared to Group 2 (P = .041). CONCLUSION: Both groups showed significant improvements in various parameters evaluated throughout the study, indicating they are equally effective in pain control and most functional and quality of life parameters. However, the stabilizing interocclusal splint treatment was superior in restoring mouth opening.