The aim of this study was evaluation of effects of two types of orthogonatic surgery ( mandibular set back versus mandibular setback and maxillary advancement ) on airway , hyoid and tongue position .
Method:
In this retrospective quasi-experimental study , 50 class III patients who had orthogonatic surgery and orthodontic treatment ( 25 in each group) were selected from the archieves of Shahid Beheshti University of Medical Sciences` Dental School and few private offices in IRAN . Cephalograms were taken at two time intervals at the start of treatment and at least one year after surgeryfrom the selected patients . 15 variables were measured after superimposition on SN line by orthosurgery X-software . The significancy of changes and groups were assessed by means of paired-T-test.
Result:
Significant decrease was seen between the dimensions of oropharynx and hypopharynx in each surgical type . Dimensions of nasopharynx increased in bimaxillary surgery and decreased in monomaxillary surgery but the changes were not statistically significant .Backward displacement was seen in hyoid and tongue position in both surgeries but their vertical position was not changed.
Conclusion:
The surgery has an significant effect on the variables regardless it`s type .