Evaluation of Salivary Biomarkers in Individuals With Bruxism

The goal of this observational study is to evaluate salivary biomarkers and perceived stress in adults with bruxism compared with healthy individuals. The study aims to determine whether salivary cortisol, immunoglobulin A (IgA), free kappa light chain (FLC-κ), free lambda light chain (FLC-λ), total free light chains, and perceived stress levels differ between individuals with bruxism and healthy controls. The main questions it aims to answer are: * Do salivary cortisol, IgA, FLC-κ, FLC-λ, and total free light chain levels differ between individuals with bruxism and healthy controls? * Is perceived stress associated with changes in salivary biomarkers in individuals with bruxism? Researchers will compare participants with bruxism and healthy control participants to evaluate differences in salivary biomarker levels and perceived stress. Participants will: * undergo a clinical examination for the diagnosis of bruxism or confirmation of healthy status; * complete the Perceived Stress Scale (PSS-14) questionnaire; * provide an unstimulated saliva sample for laboratory analysis of cortisol, IgA, free kappa light chain, free lambda light chain, and total free light chains.

Inclusion Criteria: * Adults aged 25 to 50 years. * Systemically healthy individuals. * Presence of no more than four-unit fixed partial dentures. * Absence of clinical signs of oral inflammation. * Good oral hygiene. * Individuals diagnosed with bruxism according to the study diagnostic criteria (bruxism group) or healthy volunteers without signs or symptoms of bruxism (control group). * Ability and willingness to provide written informed consent. Exclusion Criteria: * Use of medications that may affect the nervous system or salivary gland function (e.g., benzodiazepines, antidepressants). * Psychiatric disorders. * Epilepsy. * Diabetes mellitus or other pancreatic diseases. * Current corticosteroid therapy. * Cushing syndrome or Addison disease. * Pregnancy. * Current smoking. * Alcohol or substance abuse. * History of facial trauma. * Rheumatic muscle or joint disorders. * Degenerative joint disease. * Migraine. * Use of medications affecting sleep or motor activity. * Recent history of occlusal splint therapy. * Salivary gland disorders, including Sjögren syndrome or autoimmune sialadenitis.