Evaluation of the analgesic efficacy of local dexmedetomidine application.

OBJECTIVES: To determine the analgesic effects of locally applied dexmedetomidine in third molar surgery under general anesthesia. METHODS: Patients undergoing bilateral third molar surgery under general anesthesia were recruited into this double-blind, randomized, controlled study and were allocated to 3 study groups. Group D received preincision intravenous dexmedetomidine (1 mcg/kg) and direct infiltration of normal saline to the surgical wounds at the end of the surgery. Group P received preincision intravenous normal saline and direct infiltration of dexmedetomidine (1 µg /kg) to the surgical wounds at the end of the surgery. A control group (group N) received normal saline at both time points. Postoperative analgesic effects, analgesic consumption, global pain satisfaction score, vital signs, adverse events, and postoperative recovery were assessed. RESULTS: Thirty-three patients from each group were studied. Postoperative resting pain numerical rating scale scores were similar in all the groups. However, the areas under curves of numerical rating scale pain scores during mouth opening for 1 to 72 hours were significantly lower in group P than in group N (P=0.012). Both heart rate and systolic blood pressure in the immediate postoperative period were significantly lower in groups D and P than in group N (P<0.001). Patients from groups D and P were also more sedated than patients in group N (P=0.013 and P=0.007, respectively) but no difference in psychomotor recovery was observed. Respiratory rate, oxygen saturation, common side effects, wound infection rate, and global pain satisfaction scores were similar among the groups. CONCLUSIONS: Dexmedetomidine seems to have an antihyperalgesic effect when administered locally after bilateral third molar surgery. There is no delay in psychomotor recovery or increase in postoperative clinically significant adverse events.

Prevalence of postoperative complications after orthognathic surgery: a 15-year review.

PURPOSE: This study was conducted to determine the prevalence of postoperative complications after orthognathic surgery and evaluate the use of antibiotic prophylaxis in relation to the infection rate. PATIENTS AND METHODS: All patients undergoing orthognathic procedures between 1990 and 2004 were studied retrospectively by retrieving their individual medical records. Demographic data, intraoperative data (specific orthognathic procedures and duration of operation), and postoperative data (type and duration of antibiotic prophylaxis and presence of postoperative complications) were recorded. Patients noted to have suffered any postoperative complications were studied in detail, and various factors, including gender, age, duration of operation, and use of prophylactic antibiotics, were analyzed using statistical tests in relation to postoperative infection. RESULTS: A total of 2,910 orthognathic procedures were performed on 1,294 consecutive patients in the 15-year period, with 1,070 patients undergoing bimaxillary procedures and 224 patients undergoing single-jaw surgery. The orthognathic surgery-related complication rate was 9.7%, of which 7.4% was related to postoperative infection. Of the cases of infection, 58.3% were acute infection and 41.7% were chronic infection. Patients who received a single preoperative dose of antibiotics had a significantly higher infection rate (17.3%) than those who received postoperative antibiotics for various durations. CONCLUSIONS: The prevalence of infection after orthognathic surgery was relatively low given the complexity of the procedures. No particular orthognathic procedure was more susceptible to infection. A preoperative dose of prophylactic antibiotics together with at least 2 days of postoperative doses was useful in reducing the infection rate compared with only a single dose of prophylactic antibiotics.

Three-dimensional accuracy of implant placement in a computer-assisted navigation system.

PURPOSE: To evaluate the 3-dimensional accuracy of dental implant drilling in a computer-assisted navigation (CAN) system using simulated mandible models. MATERIALS AND METHODS: Eight acrylic resin models were fabricated to simulate human mandibles containing mandibular canal (MC). Computerized tomography (CT) scans were obtained for each model, and the data were transferred to the system for dental implant planning. The models were mounted on a phantom head to simulate surgical situation. The assessment parameters included entry point localization, drill path angulation, and drilling depth, which were directly measured by sectioning of the models. RESULTS: Eighty drill holes were made on the 8 models. The entry point localization showed a mean deviation of 0.43 mm (range, 0 to 2.23 mm; SD, 0.56 mm) from the plan. The angulation showed a mean deviation of 4.0 degrees (range, 0 to 13.6 degrees; SD, 3.5 degrees). The drill aimed at stopping as close to the upper border of the MC as possible without perforating it, and 65% (52) of the drill holes managed to come within 1 mm. Another 5% of the holes stopped 1 to 2 mm above the MC. None of the drill holes stopped more than 2 mm above the MC. However, 30% (24 of 80) of the drill holes perforated the upper border of MC, and the mean depth of perforation was 0.37 mm (range, 0.01 to 1.04 mm; SD, 0.28 mm). DISCUSSION AND CONCLUSION: The CAN system identified the entry location and angulation with mean deviations of 0.43 mm and 4 degrees, respectively. About two thirds of the drillings achieved accuracy within 1 mm above the MC. Thirty percent perforated into the MC, and the maximal depth was 1.04 mm. In the planning stage, the maximal depth of the implant should be at least 1.1 mm above the superior border of MC as a safety margin.

A randomized controlled trial of resorbable versus titanium fixation for orthognathic surgery.

OBJECTIVES: To determine any differences in the intra- and postoperative morbidities and complications between resorbable and titanium plating systems for fixation in orthognathic surgery. STUDY DESIGN: This prospective randomized clinical trial was conducted in the Oral and Maxillofacial Surgery unit of the University of Hong Kong. Patients with dentofacial deformities were randomly assigned into the titanium and resorbable fixation groups. Intraoperative data such as the surgical procedures, time for fixing each plate, and number of broken plates and screws were recorded. Subjective and objective parameters related to clinical morbidities were assessed postoperatively. RESULTS: A total of 60 patients with 177 osteotomies were included in this study. Eighty-seven osteotomies fixated with 196 titanium plates and 784 titanium screws were performed in 30 patients, whereas 90 osteotomies fixated with 165 resorbable plates and 658 resorbable screws were done in another 30. The postoperative infection rate was 1.53% (3/196) and 1.82% (3/165) in the titanium and resorbable fixation groups, respectively. These infections were mainly due to loose screws and wound dehiscence. The plate exposure rate was 1.02% (2/196) for the titanium group and 1.21% (2/165) for the resorbable group. The plate removal rate in the titanium and resorbable groups was 1.53% (3/196) and 3.63% (6/165), respectively. Statistically significant difference was shown in the plating time of step (mandibular body) and Hofer (mandibular subapical) osteotomies. There was no significant difference in the subjective clinical parameters such as wound discomfort, clinical stability of the osteotomy segments, palpability of plate, and overall satisfaction of the results between the 2 fixation groups. Similarly, objective parameters including wound dehiscence, rate of infection, plate exposure, occurrence of sinus tract, and palpability assessed by surgeons in both groups also showed no significant difference. CONCLUSION: Bioresorbable fixation devices offer similar function as titanium in fixation for orthognathic surgery and do not impose an increase in the clinical morbidities.