Transdermal Cannabidiol as Adjunct Therapy for Temporomandibular Disorders: Effects on Pain and Functional Outcomes

Objectives: To evaluate the safety, tolerability, and preliminary effectiveness of a transdermal cannabidiol (CBD) patch as an adjunctive therapy in patients with temporomandibular disorders (TMD), and to assess its potential impact on pain intensity, jaw function, and functional and social outcomes using DC/TMD Axis II assessment tools.

Materials and Methods: Sixty patients with sub-acute or chronic TMD were enrolled between March and June 2025 at the outpatient clinic of the Maxillofacial Surgery Department, Sapienza University Policlinico Umberto I, Rome. Diagnosis was established using DC/TMD Axis I criteria. Inclusion criteria were age 18–65 years, confirmed diagnosis of TMD, pain or functional limitation lasting ≥4 weeks, no prior CBD therapy in the last 3 months, and ability to provide informed consent. Exclusion criteria included severe joint pathology requiring surgery, active systemic disease, pregnancy or breastfeeding, allergy to CBD or patch components, concurrent cannabinoid or strong analgesic use, or psychiatric/cognitive conditions affecting reliable reporting.

Participants were allocated into two groups: 28 patients received a CBD transdermal patch (20 mg, applied over the masseteric region for 14 consecutive days) in addition to standard supportive therapy, and 32 received standard therapy alone. Clinical outcomes were evaluated at the end of the therapy and after one month using DC/TMD Axis II tools, including pain intensity (NRS 0–10), pain-free maximal mouth opening (MMO, mm), masticatory muscle palpation scores (0–3 scale), jaw function (JFLS), and social/functional impact. Safety was assessed by monitoring adverse events.

Results: No local or systemic adverse events were observed. The CBD group showed a greater reduction in mean pain intensity (NRS from 5 to 3), compared with controls (NRS from 5 to 4). Pain-free MMO increased from 33 ± 4 mm to 40 ± 4 mm in the CBD group and from 32 ± 5 mm to 37 ± 5 mm in the control group. Muscle palpation scores improved more markedly in the CBD group, and JFLS scores demonstrated improved jaw function and social participation, particularly among patients with a predominantly muscular TMD phenotype. Patients with joint-dominant TMD demonstrated a more limited improvement.

Conclusion: Transdermal CBD appears safe, well-tolerated, and may provide additional clinical benefit as an adjunct to standard therapy in muscle-predominant TMD. The use of DC/TMD Axis II tools enabled standardized assessment of functional and social outcomes. These preliminary findings have led to the initiation of an ongoing randomized controlled trial to further investigate the therapeutic role of CBD in TMD management.