Revista CEFAC
https://www.revistacefac.org.br/article/doi/10.1590/1982-0216/20262869725
Revista CEFAC
Original Articles

The immediate effects of low-intensity laser on masseter muscle’s morphological and functional parameters

Efeitos imediatos do laser de baixa intensidade sobre parâmetros morfológicos e funcionais do músculo masseter

Sara Loureiro de Souza Ferreira; Daniele Andrade da Cunha; Sávio Bastos; Marcelo Magno Ramos de Araújo; Gabriely Soares Passos; Erissandra Gomes; Kelli Nogueira Ferraz Pereira Althoff; Aline Natállia Simões de Almeida; Hilton Justino da Silva

http://dx.doi.org/10.1590/1982-0216/20262869725 Revista CEFAC, vol.28, n6, e9725, 2026
PDF English
PDF Português
SciELO
Downloads: 0
Views: 18

Abstract

Purpose: to analyze the immediate effects of low-intensity laser on morphofunctional parameters of the masseter muscle in healthy adults.

Methods: volunteers aged 18 to 39 years without stomatognathic dysfunction were randomly allocated to two placebo groups, combined for analysis, and two experimental groups. The masseter was irradiated bilaterally at three points in a single session, with 3 Joules per point in one experimental group and 6 Joules per point in the other. Temperature, thickness, tone, stiffness, elasticity, bite force and electrical activity were assessed before and immediately after the session, at rest and during function. Data were analysed with generalized estimating equations and a significance level of 0.05 was assumed.

Results: the thickness of the left masseter, during dental clenching, and the surface temperature of the left masseter changed over time, differently between groups (p=0.030 and p=0.038), with opposite directions between the two doses. The stiffness of the left masseter decreased over time (p=0.006), including in the placebo group, with no group effect or interaction, and the remaining parameters did not change.

Conclusion: a single session of low-intensity laser produced limited and dose dependent immediate changes in two of the seven parameters assessed. The reduction in stiffness occurred in all groups and could not be attributed to the irradiation.

Keywords

Low-Level Light Therapy; Muscle Fatigue; Masseter Muscle; Masticatory Muscles; Physical Functional Performance

Resumo

Objetivo: analisar os efeitos imediatos do laser de baixa intensidade sobre parâmetros morfofuncionais do masseter em adultos saudáveis.

Métodos: voluntários de 18 a 39 anos, sem disfunção estomatognática, foram alocados aleatoriamente em dois grupos placebo, reunidos para a análise, e dois experimentais. O masseter foi irradiado bilateralmente em três pontos, em sessão única, com 3 Joules por ponto em um grupo e 6 Joules no outro. Temperatura, espessura, tônus, rigidez, elasticidade, força de mordida e atividade elétrica foram avaliados antes e imediatamente após a sessão, em repouso e em função, e analisados por equações de estimação generalizadas, com nível de significância de 0,05.

Resultados: a espessura do masseter esquerdo durante apertamento dental e sua temperatura de superfície variaram no tempo de forma distinta entre os grupos (p=0,030 e p=0,038), com direções opostas entre as duas doses. A rigidez do masseter esquerdo diminuiu no tempo (p=0,006), inclusive no placebo, sem efeito de grupo nem interação, e os demais parâmetros não se alteraram.

Conclusão: uma sessão única de laser de baixa intensidade produziu alterações imediatas limitadas e dependentes da dose em dois dos sete parâmetros avaliados. A redução da rigidez ocorreu em todos os grupos e não pôde ser atribuída à irradiação.

Palavras-chave

Terapia com Luz de Baixa Intensidade; Fadiga Muscular; Músculo Masseter; Músculos da Mastigação; Desempenho Físico Funcional

Referencias

1. Ferraresi C, Hamblin MR, Parizotto NA. Low-level laser (light) therapy (LLLT) on muscle tissue: Performance, fatigue and repair benefited by the power of light. Photonics Lasers Med. 2012;1(4):267-86. https://doi.org/10.1515/plm-2012-0032 PMID: 23626925; PMCID: PMC3635110.

2. Colombo E, Signore A, Aicardi S, Zekiy A, Utyuzh A, Benedicenti S et al. Experimental and clinical applications of red and near-infrared photobiomodulation on endothelial dysfunction: A review. Biomedicines. 2021;9(3):274. https://doi.org/10.3390/biomedicines9030274 PMID: 33803396; PMCID: PMC7998572.

3. Vieira WH, Ferraresi C, Perez SE, Baldissera V, Parizotto NA. Effects of low-level laser therapy (808 nm) on isokinetic muscle performance of young women submitted to endurance training: A randomized controlled clinical trial. Lasers Med Sci. 2012;27(2):497-504. https://doi.org/10.1007/s10103-011-0984-0 PMID: 21870127.

4. Lauriti L, de Cerqueira Luz JG, Agnelli Mesquita-Ferrari R, Fernandes KPS, Deana AM, Tempestini Horliana ACR et al. Evaluation of the effect of phototherapy in patients with mandibular fracture on mandibular dynamics, pain, edema, and bite force: A pilot study. Photomed Laser Surg. 2018;36(1):24-30. https://doi.org/10.1089/pho.2017.4334 PMID: 29023221.

5. Leal-Junior EC, Vanin AA, Miranda EF, de Carvalho P de T, Dal Corso S, Bjordal JM. Effect of phototherapy (low-level laser therapy and light-emitting diode therapy) on exercise performance and markers of exercise recovery: A systematic review with meta-analysis. Lasers Med Sci. 2015;30(2):925-39. https://doi.org/10.1007/s10103-013-1465-4 PMID: 24249354.

6. Nampo FK, Cavalheri V, Dos Santos Soares F, de Paula Ramos S, Camargo EA. Low-level phototherapy to improve exercise capacity and muscle performance: A systematic review and meta-analysis. Lasers Med Sci. 2016;31(9):1957-70. https://doi.org/10.1007/s10103-016-1977-9 PMID: 27272746.

7. Larkin-Kaiser KA, Borsa PA, Baweja HS, Moore MA, Tillman MD, George SZ et al. Photobiomodulation delays the onset of skeletal muscle fatigue in a dose-dependent manner. Lasers Med Sci. 2016;31(7):1325-32. https://doi.org/10.1007/s10103-016-1979-7 PMID: 27305924.

8. Muñoz ISS, Hauck LA, Nicolau RA, Kelencz CA, Maciel TdS, Paula ARd. Effect of laser vs LED in the near infrared region on the skeletal muscle activity - Clinical study. Rev Bras Eng Bioméd. 2013;29(3):262-8. https://doi.org/10.4322/rbeb.2013.023

9. Lanferdini FJ, Bini RR, Baroni BM, Klein KD, Carpes FP, Vaz MA. Improvement of performance and reduction of fatigue with low-level laser therapy in competitive cyclists. Int J Sports Physiol Perform. 2018;13(1):14-22. https://doi.org/10.1123/ijspp.2016-0187 PMID: 28422520.

10. Rasca E, Namour A, Fauchon-Giumelli A, Nammour S. Laser phototherapy in acute posttraumatic trismus - Case-series study. Laser Ther. 2018;27(3):219-26. https://doi.org/10.5978/islsm.27_18-OR-21 PMID: 32158068; PMCID: PMC7034254.

11. Warzocha J, Gadomska-Krasny J, Mrowiec J. Etiologic factors of temporomandibular disorders: A systematic review of literature containing Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) from 2018 to 2022. Healthcare (Basel). 2024;12(5):575. https://doi.org/10.3390/healthcare12050575 PMID: 38470686; PMCID: PMC10931313.

12. Schiffman E, Ohrbach R, Truelove E, Look J, Anderson G, Goulet J et al. International RDC/TMD Consortium Network, International association for Dental Research; Orofacial Pain Special Interest Group, International Association for the Study of Pain. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: Recommendations of the International RDC/TMD Consortium Network and Orofacial Pain Special Interest Group. J Oral Facial Pain Headache. 2014 Winter;28(1):6-27. https://doi.org/10.11607/jop.1151 PMCID: PMC4478082; PMID: 24482784.

13. Herpich CM, Leal-Junior ECP, Gomes C, Gloria I, Amaral AP, Amaral M et al. Immediate and short-term effects of phototherapy on pain, muscle activity, and joint mobility in women with temporomandibular disorder: A randomized, double-blind, placebo-controlled, clinical trial. Disabil Rehabil. 2018;40(19):2318-24. https://doi.org/10.1080/09638288.2017.1336648 PMID: 28602137.

14. Maia MLM, Bonjardim LR, Quintans JSS, Ribeiro MAG, Maia LGM, Conti PCR. Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: A systematic review. J. Appl. Oral Sci. 2012;20(6):594-602. https://doi.org/10.1590/s1678-77572012000600002 PMCID: PMC3881861; PMID: 23329239.

15. de Moraes Maia ML, Ribeiro MA, Maia LG, Stuginski-Barbosa J, Costa YM, Porporatti AL et al. Evaluation of low-level laser therapy effectiveness on the pain and masticatory performance of patients with myofascial pain. Lasers Med Sci. 2014;29(1):29-35. https://doi.org/10.1007/s10103-012-1228-7 PMID: 23143142.

16. Felício CM, Folha GA, Ferreira CLP, Medeiros APM. Expanded protocol of orofacial myofunctional evaluation with scores: Validity and reliability. International Journal of Pediatric Otorhinolaryngology. 2010;74(11):1230-9. https://doi.org/10.1016/j.ijporl.2010.07.021 PMID: 20800294.

17. Almeida ANS, Ferreira SLS, Balata PMM, Cunha DA, Pernambuco L, Silva HJ. Thermography in complementary assessments of head and neck muscles: A scoping review. J Oral Rehabil. 2022;49(12):1188-96. https://doi.org/10.1111/joor.13374 PMID: 36135945.

18. Ramazanoglu E, Turhan B, Usgu S. Age related changes of superior orbicularis oris muscle in terms of tone and viscoelastic properties. J Craniofac Surg. 2022;33(1):236-9. https://doi.org/10.1097/SCS.0000000000007992 PMID: 34261972.

19. Yildiz NT, Kocaman H, Yildirim H. Predictors of the masticatory muscle activity during chewing in patients with myogenous temporomandibular disorder. Clin Oral Investig. 2023;27(11):6547-58. https://doi.org/10.1007/s00784-023-05260-3

20. Silva HJ. Surface electromyography protocols in speech therapy. Barueri, SP: Pro-fono, 2013.

21. Leonard CT, Brown JS, Price TR, Queen SA, Mikhailenok EL. Comparison of surface electromyography and myotonometric measurements during voluntary isometric contractions. J Electromyogr Kinesiol. 2004;14(6):709-14. https://doi.org/10.1016/j.jelekin.2004.06.001 PMID: 15491846.

22. Reis Durão AP, Morosolli A, Brown J, Jacobs R. Masseter muscle measurement performed by ultrasound: A systematic review. Dentomaxillofac Radiol. 2017;46(6):20170052. https://doi.org/10.1259/dmfr.20170052 PMCID: PMC5606285; PMID: 28467130.

23. Liang K, Zeger SL. Longitudinal data analysis using generalized linear models. Biometrika. 1986;73(1):13-22. https://doi.org/10.1093/biomet/73.1.13

24. Melo MB, Daldegan-Bueno D, Menezes Oliveira MG, de Souza AL. Beyond ANOVA and MANOVA for repeated measures: Advantages of generalized estimated equations and generalized linear mixed models and its use in neuroscience research. Eur J Neurosci. 2022;56(12):6089-98. https://doi.org/10.1111/ejn.15858 PMID: 36342498.

25. Pickering Rodriguez EC, Watsford ML, Bower RG, Murphy AJ. The relationship between lower body stiffness and injury incidence in female netballers. Sports Biomech. 2017;16(3):361-73. https://doi.org/10.1080/14763141.2017.1319970 PMID: 28553879.

26. Tasdemir Z, Etoz M, Koy O, Soydan D, Alkan A. Masseter muscle thickness and elasticity in periodontitis. J Oral Sci. 2020;62(1):43-7. https://doi.org/10.2334/josnusd.18-0341 PMID: 31708551.

27. Mayil M, Keser G, Demir A, Pekiner FN. Assessment of masseter muscle appearance and thickness in edentulous and dentate patients by ultrasonography. Open Dent J. 2018;12(1):723-34. https://doi.org/10.2174/1745017901814010723 PMID: 30369982.

28. Wang JS. Therapeutic effects of massage and electrotherapy on muscle tone, stiffness and muscle contraction following gastrocnemius muscle fatigue. J Phys Ther Sci. 2017;29(1):144-7. https://doi.org/10.1589/jpts.29.144 PMCID: PMC5300827; PMID: 28210061.

29. Arima T, Takeuchi T, Honda K, Tomonaga A, Tanosoto T, Ohata N et al. Effects of interocclusal distance on bite force and masseter EMG in healthy participants. J Oral Rehabil. 2013;40(12):900-8. https://doi.org/10.1111/joor.12097 PMID: 24033381.

30. Altindis T, Gungormus M. Thermographic evaluation of occlusal splint and low level laser therapy in myofascial pain syndrome. Complement Ther Med. 2019;44(1):277-81. https://doi.org/10.1016/j.ctim.2019.05.006 PMID: 31126567.
 

Submitted date:
18/04/2026

Accepted date:
06/08/2026

6ac8fe6ea953954bd019e723 cefac Articles
1982-0216 (Electrónico) 1516-1846 (Impreso)
Revista CEFAC ©2026 Todos los derechos reservados sobre el contenido de este sitio web. Los artículos siguen sus propias licencias.

Revista CEFAC

Share this page
Page Sections