BACKGROUND: Botulinum toxin has been used to treat myofascial pain and nocturnal bruxism. It remains unclear whether there is a difference in efficacy between different BTX subtypes. PURPOSE: The purpose of this study was to measure the changes in pain and maximum incisal opening in subjects with nocturnal bruxism who received either Abobotulinum A (ABA) or Onabotulinum A (OBA) and determine which is faster and longer-acting. STUDY DESIGN, SETTING, SAMPLE: The researchers implemented a retrospective cohort study. Subjects presenting to Uzman Dentaclinic outpatient clinic in Bursa, Turkey, with nocturnal bruxism between June 2023 and June 2024 were identified from a review of the electronic medical record. Subjects with systemic diseases, taking active medications and undergoing psychotherapy were excluded from the study. PREDICTOR VARIABLE: The predictor variable was the treatment assigned to the subjects received either ABA or OBA injections. MAIN OUTCOME VARIABLE(S): The primary outcome variable is therapeutic response as evidenced by changes in preoperative and postoperative pain score and maximum mouth opening. The secondary outcomes were the time to onset and duration of therapeutic response. COVARIATES: The covariates included demographics (age, sex) and preoperative (duration of complaint) variables. The postoperative covariates were postinjection discomforts and complications. ANALYSES: χ RESULTS: The sample included 100 subjects with a mean age of 35.32 ± 9.11 years (OBA group, 33.78 ± 8.36 years
ABA group, 36.86 ± 9.64 years) (P = .09). There were 8 men (16%) and 42 women (84%) in the OBA group, and 10 men (20%) and 40 women (80%) in the ABA group (P = .6). There were no statistically significant differences between the groups in terms of visual analog scale scores and maximum mouth opening values at 2 weeks, 1 month, 3 months, 4 months, and 6 months (P ˃ .05). The ABA and OBA groups showed statistically significant differences in the onset of the treatment effect (11.18 ± 2.93 days [95% CI: 10.36 to 11.99] vs 8.69 ± 2.7 days [95% CI: 7.94 to 9.44]
P ˂ .05) and its duration (5.11 ± 1.19 months [95% CI: 4.78 to 5.43] vs 7.14 ± 1.71 months [95% CI: 6.66-7.61]
P ˂ .05). CONCLUSIONS: The ABA group demonstrated an earlier onset and longer duration of the treatment effect. However, both types of BTX-A products, which are commonly used in dental clinics, provided statistically significant outcomes in terms of pain and maximum mouth opening.