This prospective observational study evaluated short-term patient-reported symptom changes in adults with bruxism-related and temporomandibular disorder symptoms who received one of three clinically selected management approaches: occlusal splint therapy, botulinum toxin type A injection, or short-term pharmacotherapy combined with splint therapy. Management selection reflected routine clinical decision-making based on clinical indication, symptom profile, shared decision-making, and patient preference and was not determined by random allocation. Symptom severity was assessed at baseline and after 3 months using the Fonseca Anamnestic Index. The primary objective was to describe the 3-month change in total Fonseca Anamnestic Index scores within the clinically selected cohorts and to explore whether longitudinal change patterns differed among them. Selected Fonseca Anamnestic Index items, severity-category changes, and clinically recorded treatment-related adverse events were also evaluated as secondary outcomes.