Hearing a distinct, sometimes hollow, sound when tapping your teeth is a common and intriguing phenomenon. This internal sound perception often sparks curiosity about how our bodies process vibrations and sound.
The Science Behind the Sound
The sound perceived when tapping teeth primarily results from bone conduction, a mechanism where sound vibrations travel directly through the bones of the skull to the inner ear. Unlike external sounds that enter the ear canal, bone-conducted sounds bypass the outer and middle ear structures entirely. The vibrations generated by tapping teeth are transmitted through the jawbone and then into the skull, reaching the cochlea, the auditory sensory organ within the inner ear.
This process is similar to how we hear our own voice, due to internal vibrations traveling through our head. The skull itself acts as a resonant structure, meaning its bones can vibrate at certain frequencies, influencing how these internal sounds are perceived. These vibrations, though subtle, are strong enough to stimulate the inner ear’s fluid, which then converts them into nerve impulses sent to the brain for interpretation as sound.
Common Explanations for the Sensation
The perception of a “hollow” or amplified sound when tapping teeth can be attributed to the natural anatomy of the skull and other factors. The air-filled sinus cavities within the skull act as natural resonators. These cavities can amplify or alter the quality of sound vibrations traveling through the bone, contributing to the “hollow” sensation.
Dental restorations, such as fillings or crowns, can also change the way sound vibrations are transmitted through the teeth. Different materials used in dental work might alter the vibrational properties of the tooth, leading to a modified internal sound perception. This is a normal variation and not a cause for concern. Additionally, slight differences in jaw alignment or how the upper and lower teeth meet, known as occlusion, can influence the force and angle of tooth tapping. These variations in bite can affect the vibrations produced and how they travel through the bone, contributing to the sound.
When to Consult a Professional
While the hollow sound from tapping teeth is a normal and harmless phenomenon, certain accompanying symptoms might indicate an underlying issue that requires professional evaluation. Consult a dentist or doctor if the sensation is accompanied by persistent pain in the teeth, jaw, or ear, especially if the pain lasts longer than two days or is severe. Other red flags include swelling in the face or jaw, fever, changes in hearing, difficulty opening or closing the mouth, or jaw locking.
If the sensation began after a recent head or dental trauma, or if the sound perception changes significantly or becomes constant and bothersome, seeking medical attention is recommended. A dentist can initially assess for dental-related causes, such as issues with fillings or bite alignment. If dental problems are ruled out, an ear, nose, and throat (ENT) specialist may be recommended to investigate other factors.