The experience of hearing a hollow sound in the ear when clicking the teeth is an auditory perception often described as echoing, booming, or underwater. This sensation frequently occurs during jaw actions like chewing, speaking, or moving the mouth. The symptom results from the close anatomical and muscular connections between the jaw structure and the middle ear cavity. It commonly points to two primary underlying mechanisms: issues with Eustachian tube function or tension within the jaw muscles.
The Connection Between the Jaw and the Middle Ear
The middle ear and the jaw are intimately linked through shared anatomy and muscular control. The temporomandibular joint (TMJ), which acts as the hinge connecting the lower jaw to the skull, is located just in front of the ear canal. This close proximity means that inflammation or movement in the jaw joint can mechanically influence nearby ear structures.
The Eustachian tube is a narrow passage connecting the middle ear to the back of the throat, responsible for equalizing air pressure. It is typically closed, opening briefly when a person swallows, yawns, or chews.
The opening is primarily controlled by the tensor veli palatini muscle, which is considered a muscle of mastication due to its shared function with the jaw muscles. When the jaw moves, these muscles are activated, directly influencing the Eustachian tube’s state and the pressure within the middle ear.
Patulous Eustachian Tube
Patulous Eustachian Tube (PET) is the most direct cause of the hollow, echoing sound, a symptom known as autophony. Unlike standard Eustachian Tube Dysfunction (ETD), where the tube is blocked, PET involves a tube that remains abnormally open, or “patent.” This constant opening allows sound waves and pressure changes from the nasopharynx to be transmitted directly into the middle ear.
With an open tube, internally generated sounds, such as the person’s own voice, breathing, or the clicking of the teeth, resonate loudly and unnaturally. The hollow sound is the internal noise of the jaw movement being conducted straight to the inner ear. This sensation can be amplified by head movements or physical exertion, which alters the pressure surrounding the tube.
Several physiological factors can contribute to the development of PET, including significant or rapid weight loss. The Eustachian tube is normally surrounded by fatty tissue that helps keep it closed; when this tissue shrinks, the tube may lose its natural closure mechanism. Dehydration and certain hormonal changes, such as those associated with pregnancy, are also recognized as potential triggers for the condition.
Temporomandibular Joint Disorders and Muscle Involvement
The hollow sound can also originate from mechanical problems involving the temporomandibular joint (TMJ) and the associated musculature. Temporomandibular disorders (TMD) are conditions that affect the jaw joint and its surrounding muscles. Since the TMJ is situated immediately next to the ear, inflammation or misalignment in the joint can radiate symptoms to the ear.
The tensor tympani muscle is a tiny muscle located within the middle ear cavity, and its primary function is to protect the inner ear by dampening loud sounds. This muscle, along with the jaw muscles, is innervated by the trigeminal nerve. Jaw dysfunction, such as chronic clenching or grinding (bruxism), can cause tension or involuntary spasms, known as myoclonus, in the nearby jaw muscles.
These spasms can extend to the tensor tympani, causing it to contract spontaneously or in response to jaw movement. The resulting tension pulls the malleus bone, stiffening the eardrum. This action sometimes creates an internal clicking, fluttering, or hollow perception. This muscular dysfunction can also affect the tensor veli palatini muscle, further disrupting the Eustachian tube’s ability to regulate pressure.
When to Seek Professional Evaluation
While the sensation of a hollow sound when clicking your teeth is often benign, certain accompanying symptoms warrant professional attention. An evaluation by a medical professional, such as an otolaryngologist (ENT specialist) or a dentist specializing in TMD, is recommended if the symptom is persistent or severely affects daily life. Consultation is particularly important if the hollow sound is accompanied by pain, persistent dizziness, or a noticeable change in hearing.
The diagnostic process often begins with a thorough physical examination of the ear canal, eardrum, and jaw movement. Specialized tests, such as tympanometry, can measure the pressure within the middle ear and assess the eardrum’s mobility, helping to diagnose conditions like PET. Non-surgical management often involves lifestyle modifications, such as managing stress to reduce jaw clenching, or using nasal sprays to address mild Eustachian tube issues.