Müftüoğlu, ÖzgeAktürk, Ezgi SunalEren, HakanGörürgöz, CansuKarasu, Hakan AlpayOrhan, KaanAkat, BoraMemikoğlu, Tulin Ufuk Toygar2023-08-212023-08-212023Müftüoğlu, O., Aktürk, E. S., Eren, H., Görürgöz, C., Karasu, H. A., Orhan, K., … Memikoğlu, T. U. T. (2023). Long-term evaluation of masseter muscle activity, dimensions, and elasticity after orthognathic surgery in skeletal class III patients. Clinical Oral Investigations, 27(7), 3855–3861. https://doi.org/10.1007/s00784-023-05004-31432-69811436-3771https://doi.org/10.1007/s00784-023-05004-3https://hdl.handle.net/20.500.12428/4478Objective: To evaluate changes in the masseter muscle after orthognathic surgery using electromyography (EMG), ultrasonography (US), and ultrasound elastography (USE) in individuals with skeletal class III anomaly over long-term follow-up and compare with a control group. Materials and methods: The study group included 29 patients with class III dentofacial deformities scheduled to undergo orthodontic treatment and orthognathic surgery. The control group included 20 individuals with dental class I occlusion. Assessment of the masseter muscles using EMG, US, and USE was performed before orthognathic surgery (T1) and at postoperative 3 months (T2) and 1 year (T3) in the study group, and at a single time point in the control group. All assessments were performed at rest and during maximum clenching. Masseter muscle activity, dimension, and hardness were analyzed. Results: Electromyographic activity of the masseter muscle during maximum clenching was increased at postoperative 1 year but did not reach control group values. On ultrasonography, the masseter muscle showed minimal changes in dimension at postoperative 1 year compared to preoperative values and remained below control group values. The postoperative increase in masseter muscle hardness at rest and during maximum clenching persisted at postoperative 1 year. Conclusion: The results of this study suggest that after orthognathic surgery, additional interventions and much longer follow-up are needed to ensure better muscle adaptation to the new occlusion and skeletal morphology. Clinical relevance: All assessment methods are useful for comprehensively evaluating changes in the masticatory muscles after orthognathic surgery.eninfo:eu-repo/semantics/closedAccessElectromyographyMasseter muscleOrthognathic surgeryUltrasonographyUltrasound elastographyArticle2773855386110.1007/s00784-023-05004-3Q2WOS:0009638914000022-s2.0-8515199750837022528