Long-Term Effects of a Single Application of Botulinum Toxin Type A in Temporomandibular Myofascial Pain Patients: A Controlled Clinical Trial

• Published in: Toxins Vol. 14; no. 11; p. 741
• Main Authors: De la Torre Canales, Giancarlo, Câmara-Souza, Mariana Barbosa, Poluha, Rodrigo Lorenzi, de Figueredo, Olívia Maria Costa, Nobre, Bryanne Brissian de Souza, Ernberg, Malin, Conti, Paulo César Rodrigues, Rizzatti-Barbosa, Célia Marisa
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29.10.2022; MDPI
• Subjects: Analgesics; Botulinum toxin; Botulinum toxin type A; Botulinum Toxins, Type A - adverse effects; Care and treatment; Chronic illnesses; Chronic pain; Clinical trials; Dosage and administration; Female; Humans; Hypotheses; Long-term effects; Masseter muscle; Mastication; Medicin och hälsovetenskap; muscle thickness; Muscles; myofascial pain; Myofascial Pain Syndromes - drug therapy; Pain; Pain - drug therapy; Pain Measurement; Patient outcomes; Patients; Statistical analysis; Temporalis muscle; temporomandibular disorders; Temporomandibular joint disorders; Temporomandibular Joint Disorders - drug therapy; Thickness; Toxins; Treatment Outcome; Brazil; muscle thickness; botulinum toxin type A; myofascial pain; temporomandibular disorders
• ISSN: 2072-6651; 2072-6651
• DOI: 10.3390/toxins14110741

This study assessed the long-term effects of botulinum toxin type A (BoNT-A) in subjective pain, pain sensibility, and muscle thickness in persistent myofascial temporomandibular-disorder pain (MFP-TMD) patients. Fourteen female subjects with persistent MFP received BoNT-A treatment with different doses (10U-25U for temporalis muscle and 30U-75U for masseter muscle). The treatment was injected bilaterally in the masseter and anterior temporalis muscles in a single session. Clinical measurements included: self-perceived pain (VAS), pain sensibility (PPT), and muscles thickness (ultrasonography). Follow-up occurred 1, 3, 6, and 72 months after treatment for VAS and PPT and 1, 3, and 72 months for ultrasonography. For statistical analysis, the Friedman test with the Bonferroni test for multiple comparisons as a post hoc test was used for non-parametric repeated measures comparisons among the evaluation times. A 5% probability level was considered significant in all tests. VAS values presented a significant decrease throughout the study ( < 0.05). Regarding PPT values, a significant increase was found when comparing baseline data with post-treatment follow-ups (p < 0.05), and even though a significant decrease was found in muscle thickness when baseline values were compared with the 1- and 3-months assessments, no differences were found when compared with the 72 months follow-up ( > 0.05). A single injection of BoNT-A presents long-term effects in reducing pain in persistent MFP-TMD patients, and a reversibility of adverse effects on masticatory-muscle thickness.