Background & Aims

The objective of this study is to characterize and treat myofascial pain temporomandibular disorders patients refractory to conventional therapies.

Methods

Methods: Patients with TMD were longitudinally evaluated for 4 months. Subjects were considered refractory when: presented a pain reduction of only 30% in three months, after being treated with conventional treatments. After baseline assessment, the patient’s were randomized according to treatment in two groups of 15 volunteers each: Botulinum toxin group (BoNT-A) and Saline solution group. The following variables were measured at baseline and after 1 and 6 months after treatment: pain intensity (Visual Analog Scale), pain sensibility (Pain Pressure Threshold), somatosensory profile (mechanical pain threshold and wind-up ratio), pain modulation (conditioned pain modulation paradigm). Also, to assess the psychosocial features were used: the Pittsburgh Sleep Quality Index, the Pain Catastrophizing Scale, the Hospital Anxiety and Depression Scale, Central Sensitization Inventory, and the Perceived Stress Scale. Between group comparisons were made using a group of healthy subjects.

Results

Results: Thirty patients were classified as refractory. Refractory patients presented: higher levels of pain intensity and lower levels of muscle pain sensitivity (p< 0.0001), a significant somatosensory gain of function in mechanical pain threshold and wind-up ratio and a significant lower (impaired) CPM effect (p< 0.05). Also, abnormal levels in almost all assessed psychosocial variables were found only in the refractory group (p< 0.001). The BoNT-A group presented a significant decrease in pain intensity at follow-ups compared with the SS group (p<0.001). Higher PPT values for BoNT-A group compared to SS (p<0.03) at all follow-ups were also found. No differences were found for mechanical pain threshold and wind-up ratio values (p>0.05) in the entire study. BoNT-A group presented the most efficient CPM effect (p<0.03) at the 1-month follow-up. Also significant group differences were fund just for the Pittsburgh Sleep Quality Index and the Central Sensitization Inventory (p<0.05).

Conclusions

Patients with refractory myofascial TMD pain exhibit a multifaceted phenotype, characterized by compromised pain perception at both somatosensory and psychosocial levels. However, a single injection session of BoNT-A demonstrates beneficial effects across the entire spectrum of pain experienced by these individuals.

References

Ernberg M, Hedenberg-Magnusson B, List T, et al (2011) Efficacy of botulinum toxin type A for treatment of persistent myofascial TMD pain: a randomized, controlled, double-blind multicenter study. Pain 152(9):1988-96
Ramos-Herrada RM, Arriola-Guillén LE, Atoche-Socola KJ, et al (2022) Effects of botulinum toxin in patients with myofascial pain related to temporomandibular joint disorders: A systematic review. Dental and Medical Problems 59(2):271–80

Presenting Author

Giancarlo De La Torre Canales

Poster Authors

Giancarlo De la Torre Canales

PhD.

Karolinska Institutet

Lead Author

E-mail

Rodrigo Loenzi Poluha

Lead Author

E-mail

Leonardo Rigoldi Bonjardim

Bauru School of Dentistry, University of São Paulo

Lead Author

E-mail

Flávia Fonseca Carvalho Soares

Lead Author

E-mail

Dyna Mara Ferreira

Lead Author

E-mail

Malin Ernberg

Karolinska Institutet

Lead Author

E-mail

Topics

  • Specific Pain Conditions/Pain in Specific Populations: Orofacial Pain