Effects of orofacial myofunctional therapy on masticatory function in individuals submitted to orthognathic surgery: a randomized trial

Abstract

ObjectivesThe esthetic and functional results of orthognathic surgery of severe dentofacial deformities are predictable, however there are differences regarding the effects on stomatognathic system. The aim was to investigate the effects of orofacial myofunctional therapy (OMT) on the masticatory function in individuals with dentofacial deformity submitted to orthognathic surgery (OGS).Material and MethodsForty-eight individuals (18-40 years) were evaluated, 14 undergoing OMT (treated group-TG), 10 without this treatment (untreated group-UTG) and 24 in a control group with normal occlusion; for clinical aspects the data of an individual was missed (n=46). Chewing was performed using the Expanded protocol of orofacial myofunctional evaluation with scores (OMES-E). Muscle tone and mobility were also analyzed before (P0), three (P1) and six months (P2) after OGS. Surface electromyography of the masseter and temporalis muscles was performed, considering the parameters amplitude and duration of act and cycle, and the number of masticatory cycles. The OMT consisted of ten therapeutic sessions along the postoperative period. The results were compared using parametric and non-parametric tests.ResultsTG showed higher scores in P1 and P2 than P0; for the masticatory type the scores in P2 were significantly higher than P0. In addition, the proportion of individuals with adequate tone of lower lip and adequate tongue mobility for TG increased significantly from P1 and P2 in relation to P0. The EMG results showed a decrease in act and cycle duration in P2 in relation to P0 and P1 for the TG; furthermore the values were close to controls. An increase in the number of cycles from P0 to P2 was also observed, indicating faster chewing, which may be attributed to an improvement of balanced occlusion associated with OMT.ConclusionThere were positive effects of OMT on the clinical and electromyography aspects of chewing in individual submitted to orthognathic surgery.

Masticatory function and related factors after oral oncological treatment: A 5‐year prospective study

“…This includes the consideration of digital planning for reconstruction and primary implant placement by the head and neck surgeon and prosthodontist. Additionally, beneficial effects of orofacial physiotherapy have been reported in orthognatic surgery, but have yet to be proven in patients with head and neck cancer . Finally, thoughtful consideration should be given in maintaining OU when clearing the dentition of potential foci in osteoradionecrosis prevention.…”

Effects of Chewing Exerciser on the Recovery of Masticatory Function Recovery after Orthognathic Surgery: A Single-Center Randomized Clinical Trial, a Preliminary Study

“…EMG data can be influenced by various factors, and they can be difficult to obtain statistically significant results because it varies from patient to patient. These factors include muscle length, muscle anatomy, electrode position, and contraction filaments characteristics [ 20 , 21 ]. In addition, the postoperative EMG variation is due to changes in the vector of muscle force and the position of muscle insertion, and an increased number of contact points [ 22 ].…”

Análise fonoaudiológica na cirurgia ortognática: estudo de caso uma década após procedimento

“…Com relação à mastigação, o padrão ideal referido na literatura é de alternância bilateralmente, com movimentos selados dos lábios e rotação da mandíbula, sem movimento da cabeça ou de outras partes do corpo, possibilitando a distribuição das forças mastigatórias com equilíbrio funcional e muscular, porém dependendo de fatores do equilíbrio oclusal [14][15][16][17] . Essa mastigação pode ser adaptada conforme as estruturas orofaciais, sendo nos casos de paciente com padrão Classe III, maior predomínio de movimento verticalizado, sem lateralização de mandíbula.…”

“…Essa mastigação pode ser adaptada conforme as estruturas orofaciais, sendo nos casos de paciente com padrão Classe III, maior predomínio de movimento verticalizado, sem lateralização de mandíbula. Pode haver pouca ou nenhuma ação dos músculos bucinadores durante a mastigação devido à discrepância das bases ósseas e das alterações oclusais [15][16][17] .…”

“…Outra observação aos pacientes Classe III é uma relação funcional direta entre a postura da cabeça e do pescoço durante a mastigação e possíveis alterações nos músculos e na postura mandibular 15,18 , bem como, com sintomas de dor, especialmente se abrem a boca para bocejar, beber, sorrir e conversar 19,20 .…”