Mahdi Sazavar; Koroush Taheri Talesh; Javad Yazdani
Abstract
Aim: The BSSO is an excellent operation for a mandibular setback. Beyond 7-8 mm of posterior repositioning of the mandible with a BSSO is difficult, and consideration should be given to an inverted L osteotomy or intraoral vertical ramus osteotomy. (IVRO) Currently the period of immobilization ranges ...
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Aim: The BSSO is an excellent operation for a mandibular setback. Beyond 7-8 mm of posterior repositioning of the mandible with a BSSO is difficult, and consideration should be given to an inverted L osteotomy or intraoral vertical ramus osteotomy. (IVRO) Currently the period of immobilization ranges between 7-21 days following the release of IMF, guiding elastics should be used to direct the mandible to maximal intercuspation.Materials and Methods: This study implied a 1 year follow- up on a group of 40 patients, who had undergone modified subcondylar osteotomy for mandibular setback. Relapse is measured as the distance from Sn perpendicular to Pog at the lateral cephalogram preoperative, one week, and one year postoperatively.Conclusion: Modified intra-oral subcondylar osteotomy with short term immobilization appeared to be a relatively safeeand reliable procedure.The mean skeletal horizontal relapse at Pog of the whole group, after one year was 0.6mm and neuro-senory disturbance (NSD) incidence alter 6 months was 2.5%.
Koroush Taheri Talesh; Javad Yazdani; Amir Mohammadi; Azin Sohrabi; Aydin Sohrabi
Abstract
Introduction: It has been advocated that treatment of dentofacial deformities with jaw osieotomies may influence upper airway morphology, and several studies has shown that mandibular setback surgery has the potential to diminish airway size and alter the hyoid bone position.Objective: The purpose of ...
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Introduction: It has been advocated that treatment of dentofacial deformities with jaw osieotomies may influence upper airway morphology, and several studies has shown that mandibular setback surgery has the potential to diminish airway size and alter the hyoid bone position.Objective: The purpose of this study was to evaluate the effect of mandibular setback on the pharyngeal airway size, and hyoid bone position and to evaluate if a pre-surgical prediction on PAS can be made or not.Materials and methods: Twenty eight pre- and post-operative (3-4 months) lateral cephalograms of 28 individuals (16 females and 12 males older than 17) who had undergone vertical ramus ostetomy setback surgery to correct skeletal class III discrepancies. Cephalograms were traced and a paired-sample t-test was used to evaluate the difference between 11 linear variables pre- and post-operative measurements. Coefficient correlation was calculated for the amounts of setback and the change in airway size.Results: The vertical and horizontal position of hyoid and hyoid-mandible distance do not change significantly. Hyoid-2nd cervical vertebra and hyoid-pogonion distances reduced significantly. In the case of upper airway indicators, the width of pharynx was calculated at 4 different levels. In all 4 levels, statistical analysis revealed significant reduction but the correlation of reduction in the size of pharynx versus amount of setback is not significant (respectively from the most superior width to the most inferior one r=0.15, r=0.13, r=0.09, r=0.19).Conclusion: This study suggested that mandibular setback surgery can decrease the pharyngeal airway size.