Assessment of ramus, condyle, masseter muscle, and occlusal force before and after sagittal split ramus osteotomy in patients with mandibular prognathism

Abstract

Assessment of ramus, condyle, masseter muscle, and occlusal force before and after sagittal split ramus osteotomy in patients with mandibular prognathism 2 Assessment of ramus, condyle, masseter muscle, and occlusal force before and after sagittal split ramus osteotomy in patients with mandibular prognathism Abstract Purpose: The purpose of this study was to examine the relationship between the morphologies of the masseter muscle and the ramus and occlusal force before and after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Patients and Methods:The study group consisted of 26 patients with mandibular prognathism. All patients underwent bilateral SSRO as well as three-dimensional computed tomography and masseter muscle, ramus and condyle were measured preoperatively and at 1 year postoperation. Occlusal force and contact area were also recorded with pressure-sensitive sheets. Results:In the cross-sectional area of the masseter muscle, there were no significant differences between the pre and postoperative statuses. However, postoperative ramus width and area were significantly larger than preoperative values (P<0.0001). Postoperative right condylar area was significantly larger than the preoperative value (P=0.0120).Occlusal force and contact area 1 year after surgery were significantly larger than the preoperative values (P=0.0016, P=0.0190).Conclusion: This study suggested that the masseter muscle area did not significantly differ from preoperative status 1 year after SSRO, although occlusal force, contact area and ramus area and width increased significantly 1 year after SSRO.

Changes in computed tomography values of mandibular condyle and temporomandibular joint disc position after sagittal split ramus osteotomy

“…The results by RBSM using frontal cephalogram suggest that the difference between the right and left sides could also be improved after surgery in the symmetry and asymmetry groups, though not completely in the asymmetry group (Ueki et al, 2009a(Ueki et al, , 2009b(Ueki et al, , 2010.…”

“…The incidence of internal derangement in asymmetrical prognathia patients is higher than in symmetrical mandibular prognathia, and this finding is associated with a difference in TMJ morphology of both sides (Ueki et al, 2000). Furthermore, a previous study suggested that the masseter muscle area did not significantly differ from the preoperative status 1 year after SSRO, although postoperatively 1 year ramus width, ramus area and condylar area were significantly larger than the preoperative values (Ueki et al, 2009a(Ueki et al, , 2009b. However, there is no study on change in condylar bone quality following SSRO.…”

Positional changes of the masseter and medial pterygoid muscles after surgical mandibular advancement procedures: an MRI study

“…30 Ueki et al found no changes in cross-sectional area and direction of the MAS muscles in 26 patients, who had undergone a BSSO setback. 31 Their measurements were made 1 year after surgery. To the best of the authors' knowledge, no similar studies have been carried out on patients undergoing an advancement BSSO to treat mandibular hypoplasia.…”

Desempenho funcional da língua na deformidade dentofacial

“…As deformidades dentofaciais são caracterizadas por más oclusões acentuadas tanto esqueletais quanto dentoalveolares (TUCKER, 2000), acompanhadas de alterações nas funções orofaciais, verificadas principalmente na mastigação (BERRETIN-FELIX; JORGE; GENARO, 2010;BIANCHINI, 1999;BIANCHINI, 2011;TRAWITZKI, 2004;TRAWITZKI, 2009), na força de mordida (SILVA, 2014;THROCKMORTON, 2006;TRAWITZKI et al, 2011;ZARRINKELK et al, 1996), na eficiência mastigatória (PICINATO-PIROLA, 2010;PICINATO-PIROLA et al, 2012;THROCKMORTON, 2006), assim como na atividade eletromiográfica (GADOTTI; BERZIN; BIASOTTO-GONZALEZ, 2005;MORENO et al, 2008;FARIAS et al, 2013;TRAWITZKI et al, 2006;TRAWITZKI et al, 2010;ZARRINKELK et al, 1996) e na morfologia dos músculos mastigatórios (KATSUMATA et al, 2004;UEKI et al, 2009;TRAWITZKI et al, 2006a).…”