Effect of surgical mandibular advancement on pharyngeal airway dimensions: a three-dimensional computed tomography study.

The aim of this study was to quantify the changes in pharyngeal airway space (PAS) in patients with a skeletal class II malocclusion managed by bilateral sagittal split ramus osteotomy for mandibular advancement, using three-dimensional (3D) registration. The sample comprised 16 patients (mean age 21.69±2.80 years). Preoperative (T0) and postoperative (T1) computed tomography scans were recorded. Linear, cross-sectional area (CSA), and volumetric parameters of the velopharynx, oropharynx, and hypopharynx were evaluated. Parameters were compared with paired samples t-tests. Highly significant changes in dimension were measured in both sagittal and transverse planes (P<0.001). CSA measurements increased significantly between T0 and T1 (P<0.001). A significant increase in PAS volume was found at T1 compared with T0 (P<0.001). The changes in PAS were quantified using 3D reconstruction. Along the sagittal and transverse planes, the greatest increase was seen in the oropharynx (12.16% and 11.50%, respectively), followed by hypopharynx (11.00% and 9.07%) and velopharynx (8.97% and 6.73%). CSA increased by 41.69%, 34.56%, and 28.81% in the oropharynx, hypopharynx, and velopharynx, respectively. The volumetric increase was greatest in the oropharynx (49.79%) and least in the velopharynx (38.92%). These established quantifications may act as a useful guide for clinicians in the field of dental sleep medicine.

Clinical evaluation of immediate loading of titanium orthodontic implants.

BACKGROUND: Skeletal anchorage using dental implants, miniplates, miniscrews and microscrews provides an absolute anchorage for tooth movement. Miniscrew and microscrew implants have many benefits such as ease of placement and removal and immediate orthodontic force application. METHODS: Fifteen subjects in the permanent dentition with an overjet ≥6 mm received treatment with the 0.018-inch pre-adjusted edgewise appliance system (Roth prescription) and extraction of all first premolars. Titanium orthodontic implants were placed in both the upper quadrants and were immediately loaded with elastic chain from the implant head to the sectional arch wire. RESULT: The overall success rate of immediate loaded titanium orthodontic micro implants (OMI) in the present study was 83.33%, with a mean chairside time of 15.33 min of placing two implants in each patient. Peri-implant inflammation was the only complication observed. Most failures were in the initial part of the study. There was no significant difference in the success rate of implants based on sex, side of placement (right or left) and type of malocclusion. CONCLUSION: The OMIs used in the present study proved to be effective and well tolerated in producing immediate orthodontic anchorage for the retraction.

Management of Mandibular Fractures.

BACKGROUND: To evaluate the cases of mandibular fractures treated by open reduction and rigid fixation at the Armed Forces Medical College, Pune. METHODS: Two hundred and thirteen mandibular fractures cases were treated by open reduction and rigid fixation from Jun 1998 to Jun 2006. These were retrospectively analyzed based on the following patient related factors i.e. mode of injury, age and sex distribution, site of injury, associated injuries and surgical treatment. RESULT: The significant finding was that the most common etiology for fracture mandible was road traffic accidents (RTA), [196 (92%)]. Of the patients who reported, 147 (95.4%) were males in the third decade of life. 96 (45%) patients had parasymphysis fractures, 65 (30.5%) had angle fractures, 33 (15%) subcondylar fractures, 17 (7.9%) body fractures and 2(0.9%) had ramus fracture. Early intervention using open reduction and internal fixation was the protocol followed which resulted in minimum morbidity and complications. CONCLUSION: As RTA especially two wheelers accidents appeared to be the most common cause of mandibular fractures, use of suitably designed protective head gear (crash helmets) is advisable. Moreover open reduction and rigid internal fixation appears to be the suitable treatment modality in successful treatment of mandibular fractures in reducing morbidity and complications and ensuring early return to normalcy.