Efficacy of Physical Therapy on Maximal Mouth Opening in Patients Affected by Disc Displacement and Degenerative Temporomandibular Joint Diseases: A Systematic Review

BACKGROUND: Among temporomandibular disorders (TMDs), the main arthrogenic entities are disc-condylar complex disorders and degenerative diseases. OBJECTIVE: This systematic review aimed to evaluate the effectiveness of physiotherapy in patients with temporomandibular joint (TMJ) disorders. METHODS: A systematic review was conducted across PubMed, Scopus, and Web of Science until January 2026 to search for studies including patients with a diagnosis of intracapsular TMD as participants; physical therapy or physical therapy combined to other conservative approaches as intervention; placebo, sham treatments, oral pharmacological anti-inflammatory drugs, behavioral therapy, or other conservative approaches as comparison; maximal mouth opening (MMO) as outcome. RESULTS: Out of 1578 identified records, 10 studies were included. A total of 354 subjects were analyzed, of which 213 performed a rehabilitation technique and 141 were included in the control group. Although the randomized trials reported improvement in MMO, pain, and function, a major limitation was the lack of standardized physiotherapy protocols across trials. CONCLUSION: Findings from the present systematic review showed that physiotherapy (active and passive jaw exercises, associated with relaxation techniques) might improve MMO. Further studies with uniform protocols and high-quality randomized trials are needed to validate the efficacy of multimodal treatments in arthrogenic TMD subtypes.