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Purpose: The gold-standard for reconstruction of large mandibular defects is the use of free flaps of vascularized autologous bone with the fibula as the preferred donor site. The use of "custom cutting guides" for this indication is becoming increasingly prevalent. But cost of the procedure averages around 2,500 dollars per patient excluding treatment and entails selection criteria. We think it is possible to standardize mandibular reconstructions from an anatomical mean. The objective of this study was to perform a mandibular morphometric analysis in order to obtain a set of "mean" measurements, which can be used by all surgeons interested in mandibular reconstruction., Methods: We performed a morphometric analysis consisting of three-dimensional mandibular reconstructions of 30 men and 30 women. Several reference points were set and defined to evaluate specific lengths and angles of interest. We conducted an intra and inter-sexual descriptive analysis of measurements obtained., Results: We did not identify any major intra-sexual differences within each group. The gonial angle is more open in women and the measurements characterizing the basilar contour are more prominent in men. We did not identify any differences in alveolar region parameters., Conclusion: The results of this study constitute a morphological tool for surgeons, from bone graft to free flap. These results also confirm us that the use of «custom cutting guides» for mandibular reconstruction may be excessive. It is pertinent to examine the value of "custom made" mandibular reconstructions since the differences observed are of the order of millimeters., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Bilateral sagittal split osteotomy (BSSO) of the mandibular ramus is the most frequent orthognatic surgery. The risk of neurosensory disorders remains high even their incidence varies according to numerous publications. The anatomical location of the alveolar pedicle seems to be one of the most important factors in these disorders. The aim of this study was to determine its exact role., Material and Method: We performed a retrospective study on 76 patients and 152 osteotomy sides, all of them operated according to the Epker technique by the same surgeon between 2000 and 2004. For each operative side we noted the position of the inferior alveolar nerve during the split: Type I entirely in the internal cortical bone, Type II partially in the external cortical bone, Type III mostly or completely in the external cortical bone. The neurosensory disorders were recorded during clinical examination and simply classified into two categories: "absent" or "present". The outcome was noted during the postoperative follow-up at D1; D15; M1,5, M6, and M12. After that, it was documented through a written questionnaire or telephone conversation., Results: Since there was no difference between the right and the left sides, the study enclosed all of the operative sides together (152). The anatomical distribution was: 97 Type I (63.8%), 28 Type II (18.4%), and 27 Type III (17.8%). Immediate postoperative neurosensory disorders (D1) occurred on 74.3% of sides, with important significant differences between Type I (64.9%) on one hand, Type II (89.2%) and Type III (92.6%) on the other hand. At one year of follow-up, the rate of neurosensory disorders was 20.4% with also a difference between Type I (13.4%) and Types II and III (35.7% and 29.6%)., Discussion: The anatomical location of the alveolar pedicle seems to be important. This study confirms previously published studies and raises the question of CT scan assessment before performing BSSO.

Introduction: Cases of obstructive sleep apnea syndrome have been described after setback osteotomy. Although such cases are rare, they emphasize the importance of taking into account the structure of the upper airways when performing this type of procedure. We studied the modifications provoked in the upper airways by mandibular setback osteotomy performed for dysmorphism., Material and Method: We conducted a retrospective cephalometric study in a series of 25 patients. Preoperative and late postoperative films were digitalized to obtain a precise measurement of the bone displacements and changes in the caliber of the retrovelar and retrolingual spaces. The statistical analysis examined the parameters modified by surgery, particularly airway parameters, and those factors which influenced these modifications., Results: We observed a reduction in the retrolingual space [mean 1.7 mm (p < 0.05)] and displacement of the hyoid bone [mean 2 mm lowering compared with the bi-spinal plane (p < 0.05) and 4.1 mm setback in the Francfort projection (p < 0.01)]. These modifications were not correlated with the mandibular setback (measured as the gonial mental angle) but were strongly dependent on variations in the gonial angle. In 20% of the cases, mandibular setback produced a paradoxical effect: enlargement of the airways., Discussion: Little work has been done on the modifications in the upper airways provoked by osteotomies. Mandibular setback osteotomy can, though only a few cases have been reported, create an anatomic situation favoring obstructive sleep apnea. This series demonstrated the very wide variability of the effects on the upper airways., Conclusion: The risk of apnea should be included as an important parameter in assessing indications for setback osteotomy.

The aim of this work was to study long-term airways space changes after maxillomandibular osteotomy in order to assess benefit of this surgery in case of obstructive sleep apnea syndrome. Preoperative and postoperative cephalometric airway spaces evaluation of 43 patients (who did not have obstructive sleep apnea) was done. Analysis revealed no charge in velopharyngeal space, lingual-pharyngeal augmentation in case of mandibular advancement. Hyoid bone position was not modified by osteotomy. Signification and interest of this finding for patients with obstructive sleep apnea are discussed through literature data.

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