Objectives. Nocturnal bruxism can be managed by botulinum toxin (Botox (R)) in patients who have not responded to conservative treatment. The aim of this study was to evaluate the efficacy of botulinum toxin A (BTXA) in the treatment of nocturnal bruxism. Material and Methods. The retrospective study comprised 25 female patients, aged 23-55 years (mean 35.84 +/- 8.41 years). All patients received a single injection of BTXA in the right and left masseters. Evaluation was made by Visual Analogue Scale (VAS) values, complaint duration, onset of effect, and duration of effectiveness. Results. BTXA produced significant improvements in pain scores. Only 2 adverse events (8%) were recorded. Conclusion. BTX-A is effective in the treatment of nocturnal bruxism.