Efficacy and Safety of HA35 Gel Nighttime Occlusive Application for TMD Pain

This prospective, single-center, single-arm, open-label pilot clinical study investigates the efficacy and safety of nighttime occlusive topical 10% high-concentration 35 kDa hyaluronan (HA35) gel for relieving pain and muscle over-tension associated with temporomandibular joint disorder (TMD).

Eligible subjects will apply ≥6.5 mL of HA35 gel to the TMJ region before sleep, covered with an occlusive film for 8-12 hours overnight. Pain intensity and muscle over-tension will be assessed using a 0-10 Numeric Rating Scale (NRS) at baseline, 60 seconds after application, and 12 hours after application.

Local skin reactions, adverse events, and overall tolerability will be monitored continuously.

This is a non-invasive, non-pharmacological intervention with minimal risk to participants. All procedures will be conducted in accordance with the Declaration of Helsinki, and written informed consent will be obtained from all subjects prior to enrollment.

• 10% High-Concentration 35 kDa Hyaluronan (HA35) Topical Gel (Device), also known as HA35 TMJ Gel, Nighttime Occlusive HA35 Gel: Topical gel containing 10% high-concentration 35 kDa hyaluronan fragment. Applied to the TMJ area under nighttime occlusive conditions to rapidly relieve TMD-related pain and muscle over-tension.

Primary outcomes

• Change in TMJ Pain NRS Score (0-10) [Baseline to 60 seconds and 12 hours after application]: Change in TMD-related TMJ pain intensity measured by 0-10 NRS, 0 = no pain, 10 = worst imaginable pain.

Secondary outcomes

• Change in Jaw Muscle Over-Tension Intensity (0-10 NRS Score) [Baseline to 60 seconds and 12 hours after application]: Change in jaw muscle over-tension intensity, assessed using a 0-10 Numeric Rating Scale (NRS), where 0 = no muscle tension and 10 = maximum, painful muscle over-tension.
• Incidence and Severity of Local Skin Adverse Events [From study enrollment (baseline) to the end of the 12-hour observation period]: Number and severity of treatment-related local skin adverse events (e.g., redness, irritation, allergic reaction) reported during the study. Severity is graded using the Common Terminology Criteria for Adverse Events (CTCAE).

Sex: All, ages: 18 Years to 60 Years

Inclusion Criteria:

* Age 18-60 years, male or female
* Clinically diagnosed with TMD with TMJ pain and/or muscle over-tension
* Baseline TMJ pain NRS score ≥3
* History of bruxism or jaw clenching
* Ability to complete NRS assessments independently
* Signed written informed consent

Exclusion Criteria:

* TMJ treatment (medication, physical therapy, injection) within 2 weeks
* Topical analgesic/anti-inflammatory use within 24 hours
* Skin damage, allergy, or infection in the TMJ application area
* Severe systemic disease (cardiovascular, diabetes, autoimmune)
* Known hypersensitivity to hyaluronan or gel components
* Pregnant or lactating women