Dental Occlusion’s Brain and Hearing Health Links

A new review paper from researchers at Nanjing University has synthesized the evidence for a two-way street between how your teeth fit together and how your brain functions. The work by Bingfeng Dai, Ziming Zhao, and Jie Lin argues that sensory input from dental occlusion—the contact between upper and lower teeth—can directly modulate sensorimotor control, cognitive function, and even emotional states. Conversely, disrupted brain function can negatively impact the homeostasis of the jaw. This bidirectional relationship has significant implications for understanding and treating conditions involving auditory sensitivity and emotional regulation.

How Researchers Investigated the Occlusion-Brain Link

The review by Dai and colleagues evaluated evidence from both animal model studies and human clinical research. They focused on synthesizing findings from neuroimaging (like fMRI), molecular studies, and physiological experiments to build a coherent picture. A central part of their analysis was evaluating the strength of evidence, clearly distinguishing between data from controlled animal experiments—which can suggest mechanisms—and findings from human patients, which reflect real-world clinical complexity. They also systematically accounted for major confounding variables, such as the presence of periodontitis, which can cause its own systemic inflammation and potentially skew results. The authors were explicit about the methodological limitations in the field, particularly the lack of standardized protocols in neuroimaging studies of occlusion, which currently hampers the ability to compare results across different research groups.

Occlusion as a Modulator of Brain Structure and Function

The findings indicate that the sensory information generated when teeth meet is not an isolated signal. It travels via the trigeminal nerve and has been shown to modulate activity in the sensorimotor cortex, cerebellum, and limbic system. In practical terms, this means input from your bite can influence areas of the brain responsible for movement precision, emotional response (like anxiety), and higher cognitive functions. Animal studies provide mechanistic clues, showing that altered occlusion can change neurotransmitter levels and neuronal plasticity in these brain regions. This provides a plausible biological pathway for how dental issues could contribute to or exacerbate conditions defined by sensory and emotional dysregulation. For individuals with conditions like hyperacusis or misophonia, where the brain’s processing of sound is linked to strong emotional and physiological reactions, an unresolved occlusal issue could represent a persistent source of aberrant sensory input, potentially worsening symptoms.

The Reverse Pathway: When Brain Dysfunction Affects the Jaw

The relationship is reciprocal. The review highlights that neurological or psychiatric conditions can disrupt the fine motor control and sensory feedback loops required for stable occlusion. For example, chronic stress or anxiety, which alter limbic system function, can lead to increased jaw clenching and bruxism (teeth grinding). This creates a self-perpetuating cycle: stress worsens occlusal forces, and the resulting abnormal dental sensory input may then feed back to amplify the brain’s stress response. This cycle mirrors other documented bidirectional relationships in health, such as the one between tinnitus and sleep disturbance. Furthermore, systemic inflammation from conditions like periodontitis may have neuroinflammatory effects, potentially influencing broader neurological health—a factor that must be controlled for in research.

Practical Implications for Hearing and Sensory Health

This synthesis moves the discussion from theory to practical consideration. For clinicians treating tinnitus, hyperacusis, or misophonia, a standard evaluation might now need to include questions about jaw pain, teeth grinding, or dental history. An undiagnosed temporomandibular joint (TMJ) disorder or malocclusion could be a contributing factor to a patient’s auditory sensitivity and distress. The research suggests that interdisciplinary collaboration between dentists, neurologists, and audiologists is not just beneficial but may be necessary for complex cases. Addressing occlusal stability through dental interventions could, in some patients, help reduce the overall sensory burden on a hypervigilant nervous system. This approach aligns with a broader trend in managing sensory processing disorders by looking at the entire somatosensory system and its link to emotional states.

However, Dai and colleagues caution against over-interpretation. The evidence, while compelling, comes from a field with methodological challenges. Patients and providers should view this as one piece of a larger puzzle. A comprehensive treatment plan for sound sensitivity disorders would still prioritize evidence-based approaches like sound therapy and cognitive behavioral therapy, while considering the occlusion-brain link as a potential modifiable factor. The ultimate goal, as highlighted in the review, is to foster more rigorous, standardized research to move from correlation to clearer causation and effective integrated treatments.

Source: Dai, B., Zhao, Z., & Lin, J. (2026). The bidirectional interactions between dental occlusion and brain function. Frontiers in Neurology, 10.3389/fneur.2026.1841493.