Preliminary clinical evidence on the efficacy of topical cannabidiol in the management of myogenous temporomandibular disorders: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to evaluate the current preliminary clinical efficacy of topical cannabidiol (CBD) in managing myogenous TMDs. A literature search was performed through MEDLINE (via PubMed), Scopus, Web of Science, and Clinical trial.gov databases. In addition to citation chasing of the included studies, focusing on studies published in English up to September 2026. This review was prospectively registered (Prospero, No. CRD420261293459). This systematic review was carried out independently by three researchers in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, utilizing both controlled vocabulary terms (such as MeSH) and free-text keywords related to Cannabidiol (e.g., “Cannabidiol,” “CBD,” or “Cannabis”). A modified PICOS framework was applied to address the research question: What evidence currently exists regarding the efficacy of Cannabidiol in managing myogenous temporomandibular disorders? Heterogeneity was evaluated through visual inspection of the forest plots and quantified using the I² and Chi-square tests, in case of heterogeneity, a random-effect model was used, otherwise a fixed-effect model was used. The pooled result was judged as heterogeneous when the Chi-square P-value was less than 0.1. A total of 744 records was identified through the preliminary search. After resolving 176 duplicates, 568 articles were included in the title and abstract screening phase, followed by the full-text screening phase. Finally, two studies were included in this review as they met the eligibility criteria. The two randomized studies included were assessed for risk of bias using the RoB 2 tool. Both studies demonstrated a low risk of bias across all domains. The overall effect of the VAS, righ sEMG, left sEMG, favored CBD with mean difference of -2.89 [-3.58, -2.21], -0.06 [-0.09, -0.04], -0.07 [-0.12, -0.02] respectively. The certainty of evidence for pain intensity, right and left masseter muscle activity was rated as low due to imprecision and indirectness. Topical CBD significantly reduced masseter muscle activity and pain intensity in myogenous TMD patients. However, the current evidence remains limited by the small number of studies and short follow-up periods. Further large-scale randomized clinical trials are required before routine clinical recommendation.