Masseter TENS Therapy for Bruxism-Related Tinnitus

A new study from Ankara University offers a direct, non-invasive approach for a specific form of tinnitus. Researchers found that applying electrical stimulation to the jaw muscle significantly reduced tinnitus severity and related jaw discomfort in individuals whose tinnitus is linked to bruxism, or teeth grinding.

Targeting the Jaw-Muscle Connection

The research, published in Brain and Behavior, focused on a subset of tinnitus cases where the phantom sound is connected to somatosensory issues, specifically bruxism. Bruxism involves chronic clenching or grinding of teeth, which overworks the masseter muscles in the jaw. This muscular dysfunction can influence auditory pathways, potentially generating or worsening tinnitus perception.

Led by Zehra Aydoğan and colleagues, the team investigated whether modulating the masseter muscle could, in turn, modulate the tinnitus. They used a specific form of transcutaneous electrical nerve stimulation (TENS) with pencil-shaped electrodes, a method chosen for its precise application to the muscle.

This approach aligns with a growing understanding of tinnitus as a network disorder. As explored in related research on cerebellar insights for tinnitus, abnormal neural activity is not confined to the auditory cortex but involves interconnected brain regions responsible for movement, sensation, and attention.

How the Study Was Conducted

The study enrolled 31 adults with normal hearing and chronic, subjective tinnitus that they and their clinicians associated with bruxism. Participants were randomly split into two groups: an active treatment group (18 people) and a control group (13 people) that received no intervention during the study period.

The treatment group received pencil-electrode TENS on their masseter muscles four times per week for five weeks, totaling 20 sessions. The researchers measured outcomes using a battery of validated tools before and after the treatment period. These included:

• Tinnitus Handicap Inventory (THI): To measure the functional, emotional, and catastrophic impact of tinnitus.
• Visual Analog Scales (VAS): For subjective ratings of tinnitus severity and jaw discomfort.
• Generalized Anxiety Disorder-7 (GAD-7): To assess anxiety levels.
• Oral Behavior Checklist (OBC): To track parafunctional jaw habits.
• Mandibular Range of Motion (ROM): A physical measure of jaw movement.
• SF-36 Quality of Life Scale: To gauge broader health impacts.

Significant Reductions in Tinnitus and Jaw Discomfort

The results showed clear, positive changes in the TENS group that were not seen in the control group. The active treatment led to significant reductions in the total THI score and all its subscales, meaning participants felt their tinnitus was less intrusive and distressing.

On the 0-10 VAS scales, ratings for both tinnitus severity and bruxism-related jaw discomfort dropped significantly. Physically, mandibular range of motion improved, and self-reported oral parafunctional behaviors on the OBC decreased. The benefits extended beyond the jaw and ears; anxiety scores (GAD-7) fell, and participants reported better scores on the pain and general health subscales of the SF-36 quality of life survey.

The control group, by contrast, showed no significant changes on any of these measures over the same period. This strengthens the conclusion that the improvements were due to the TENS therapy and not simply the passage of time or a placebo effect.

Practical Implications and a New Treatment Pathway

This study, available with full details via PMID: 42050847, points to a practical and promising treatment for a identifiable patient group. For clinicians, it underscores the importance of assessing jaw health and bruxism in tinnitus patients. A treatment targeting the masseter muscle could be a viable option when a somatosensory link is suspected.

For patients, the findings offer a non-invasive, drug-free avenue for relief that addresses both the tinnitus symptom and its potential muscular source. The dual improvement in jaw function and tinnitus perception is a key advantage, treating what may be a common underlying dysfunction. The mechanism is thought to be somatosensory neuromodulation—the electrical input from the jaw muscle may help normalize the misfiring neural networks responsible for generating the tinnitus signal.

This work adds to a spectrum of targeted approaches for hearing-related disorders. Just as research is differentiating the neural bases of misophonia vs hyperacusis, this study helps define a treatable subtype of tinnitus. It also complements other physical intervention strategies, such as those discussed in our article on masseter stimulation as a new tinnitus treatment approach.

The next steps will involve larger, multi-center trials to confirm these results and refine treatment protocols. Determining how long the benefits last and whether maintenance sessions are needed will be important. However, for individuals with bruxism-associated tinnitus, this research provides a clear, evidence-based reason to explore the connection between their jaw and their ears.