Teeth grinding, known as bruxism, involves the forceful clenching or grinding of the teeth. Tinnitus is the perception of sound, such as ringing, buzzing, or clicking, when no external sound is present. There is a recognized connection between bruxism and the development or worsening of tinnitus. This relationship is often classified as somatosensory tinnitus, meaning the sound perception is influenced by sensory signals from the body’s musculoskeletal system, particularly the head and neck.
The Anatomical Relationship Between Jaw and Ear
The structural proximity of the jaw joint to the ear explains why bruxism affects hearing-related symptoms. The temporomandibular joint (TMJ), which connects the lower jawbone to the skull, sits directly in front of the ear canal. Since the joint is separated from the middle ear cavity by only a thin layer of bone, inflammation or misalignment in the jaw can transfer pressure to the auditory structures.
The trigeminal nerve (Cranial Nerve V) provides a neurological link by innervating the TMJ, major jaw muscles (masseter and temporalis), and the tensor tympani muscle within the middle ear. Chronic jaw strain irritates the trigeminal nerve, which can disrupt signals traveling to the brain’s auditory processing centers. Additionally, the discomalleolar ligament may connect the TMJ directly to the malleus, a small bone in the middle ear, transmitting physical tension.
How Teeth Grinding Triggers Tinnitus
The chronic force generated by teeth grinding leads to physiological changes that irritate the auditory system. Bruxism causes hyperactivity and fatigue in the masticatory muscles, such as the masseter and temporalis. This sustained tension can radiate to surrounding structures, including the muscles connected to the middle ear.
Muscular Hyperactivity
The tensor tympani muscle dampens sounds by stabilizing the eardrum. Jaw muscle hyperactivity, often from clenching, can cause the tensor tympani to spasm or become hypertonic, meaning it remains in a state of increased tension. This abnormal activity can create the sensation of ear fullness, a popping sound, or ringing.
Neural Cross-Talk
Chronic strain on the TMJ can lead to temporomandibular disorders (TMD), involving inflammation and joint misalignment. This inflammation irritates the trigeminal nerve, causing it to send abnormal signals to the brainstem. This irritation leads to neural “cross-talk,” where somatosensory signals from the jaw modify or amplify sound perception in the brain. This mechanism explains why moving the jaw or neck can alter the pitch or volume of bruxism-related tinnitus.
Treatment Focused on Jaw Tension
Managing tinnitus caused by teeth grinding requires a multi-faceted approach focused on reducing strain on the jaw structures. Treatment begins with diagnosis, where a healthcare provider assesses jaw tenderness, checks for joint sounds, and reviews clenching habits. Addressing stress and anxiety is also a part of the treatment plan, as these are frequent underlying triggers for bruxism.
Oral Appliances
A common intervention is the use of a custom-fitted oral appliance, such as a night guard or occlusal splint. This device creates a physical barrier between the teeth, preventing the destructive contact of grinding and clenching. By reducing the force exerted on the joint, the night guard allows the jaw muscles to relax and heal, reducing muscular tension that contributes to auditory symptoms.
Physical Therapy and Behavioral Management
Physical therapy targets the muscles of the jaw, neck, and shoulders to release chronic tension. Therapists use massage, stretching, and specific jaw exercises to improve range of motion and reduce stiffness in the masseter and temporalis muscles. These exercises retrain the muscles for proper function and reduce the hyperactive state affecting the middle ear. Cognitive behavioral therapy (CBT) and relaxation techniques can also help manage the stress that fuels the grinding.