Differential effectiveness of photobiomodulation in muscular and articular temporomandibular disorders: a systematic review and critical appraisal.

To evaluate and compare the clinical effectiveness of photobiomodulation (PBM) in managing temporomandibular disorders (TMDs) of muscular versus articular origin, drawing from randomized controlled trials (RCTs) assessing pain reduction and improvement in mandibular function. This systematic review and meta-analysis adhered to PRISMA 2020 guidelines and was registered with PROSPERO (CRD420251029633). Comprehensive searches were conducted in PubMed, MEDLINE, LILACS, and the Cochrane Library for articles published up to March 31, 2025. Eligible studies were RCTs examining PBM in patients with muscular or articular TMDs, reporting outcomes on pain (Visual Analogue Scale [VAS]) and/or mandibular function (Maximum Mouth Opening [MMO]). Risk of bias was assessed via the Cochrane RoB 2.0 tool, and meta-analyses employed random-effects models with subgroup analyses based on TMD subtype. Eighteen randomized controlled trials (n = 1038 participants) were included: 11 focused on muscular TMD, 4 on articular TMD, and 3 on mixed types. PBM demonstrated significant improvements in pain and mandibular function across all subtypes. Meta-analysis revealed consistent benefits for pain (SMD = - 0.84; 95% CI: -1.18 to - 0.51) and function (SMD = 0.72; 95% CI: 0.38 to 1.05). Trials involving articular TMD showed the most robust and homogeneous effects, suggesting greater PBM efficacy in intra-articular conditions. Photobiomodulation is an effective modality for the management of both muscular and articular TMDs. The data indicate superior and more consistent outcomes in articular presentations, potentially due to PBM's anti-inflammatory properties. These findings support the implementation of subtype-specific PBM protocols in clinical practice.