Intraoperative complications of sagittal osteotomy of the mandibular ramus: incidence and management

The intraoperative complications occurring with 256 sagittal osteotomies operated by two different osteotomy designs are presented. Intraoperative complications occurred in 8.2% of the cases. Aside from operator experience and skill, complications appeared to be related to the osteotomy design and attention to detail during the operation.     

Radiographic appearance and population distribution of the pneumatized articular eminence of the temporal bone

The pneumatized articular eminence of the temporal bone (PAT) is a cavity similar to that seen in the mastoid process that occurs in the zygomatic process of the temporal bone. Panoramic radiographs of 1061 dental school patients were reviewed to determine the radiographic appearance and population characteristics of this finding; PAT was found in 28 patients (2.6%). The mean age of the patients was 32.5 years; there was no sex predilection and four patients showed this defect bilaterally. Two radiographic types of PAT were identified, unilocular and multilocular. Panoramic radiography appears to be an efficacious method to display the articular eminence for visualization of PAT. Due to the relatively common occurrence of PAT and the increasing amount of surgery of the temporomandibular joint, visualization of this defect becomes important for the clinician planning surgical manipulation of the articular eminence.     

Surface finishing of dental porcelain

A technique is presented to polish a porcelain surface whose natural glaze has been broken by grinding. The technique involves the use of a hard rubber wheel, fine wet pumice, and wet tin oxide. A comparison of the polished and naturally glazed porcelain surfaces of vacuum-fired porcelain appear similar both clinically and under an SEM.     

Components of adult Class II open-bite malocclusion

In an effort to identify the frequency and distribution of the dental and skeletal components of adult Class II malocclusion with and without open-bite, 124 adults, half of whom had an anterior open-bite, were evaluated. Significant differences (P less than 0.05) between the open-bite and non-open-bite groups were found for the following measurements: the posterior maxilla exhibited vertical excess in the open-bite group; the maxillary occlusal plane was less steep in the open-bite group; the mandibular occlusal plane was more steep in the open-bite group; the gonial angle was higher in the open-bite group; the mandibular plane angle was higher in the open-bite group; the mandibular ramus was positioned in a more downward and backward (clockwise) location in the open-bite group; the total and lower anterior facial height were increased in the open-bite group; and the mandible was less protrusive in the open-bite group. No significant intergroup differences were noted in the cranial base, the anteroposterior position of the maxilla or of the upper and lower incisors, the palatal plane, posterior facial height, mandibular ramus height, or mandibular body length. The results of this analysis indicate that the average Class II open-bite malocclusion is characterized by aberrations in both the maxilla and the mandible. Therapy, therefore, may frequently require surgical intervention in both jaws to successfully correct this deformity.     

Components of adult class III malocclusion

To identify the skeletal and dental relationships of adults who have class III malocclusion, lateral cephalograms of 302 adult patients who had a class III molar and cuspid relationship were traced. Ninety-four of the patients had had presurgical orthodontic treatment and 208 had not. The tracings were digitized, and the following sets of measures were analyzed: maxillary skeletal position; maxillary dentoalveolar position; mandibular dentoalveolar position; and mandibular skeletal position. In addition, the mandibular plane angle and lower anterior facial height were measured as an indicator of vertical facial dimensions. None of these values demonstrated significant gender differences except lower anterior facial height; therefore, the subjects were treated as a group. Although there was considerable variation among patients, the most common combination of variables was a retrusive maxilla, protrusive maxillary incisors, retrusive mandibular incisors, a protrusive mandible, and a long lower facial height.     

Aspiration of an unerupted permanent tooth during maxillofacial trauma

Aspiration of teeth during maxillofacial trauma can occur whether or not there is loss of consciousness. Even when all erupted teeth are clinically present, there is a possibility of aspiration of unerupted teeth avulsed from the line of fracture. Many aspirated foreign bodies occur without presenting signs and symptoms and may be missed on the chest radiography because of superimposition by other radiodense structures. When broken or missing teeth or parts of dentures are unaccounted for, aspiration must be considered. In symptomless cases, expiratory anteroposterior chest radiographs are useful in detecting obstructive emphysema or overinflation. Deep inspiratory films or fluorscopy may show a shift of the mediastinum to the affected side. Bronchoscopy is the treatment of choice. Prophylactic steroids and antibiotics are no longer considered effective in reducing morbidity and mortality due to aspiration.     

Amnesia,pain experience,and patient satisfaction after sedation with intravenous diazepam

Recovery time, the effect of sedation or amnesia on postoperative pain, and patients' opinions of the sedation were studied. Forty operations were performed on 20 patients. Each patient had four impacted third molars removed in two sessions, one in which a new emulsion form of diazepam (Diazemuls^®) was used, and one in which no sedation was used. The recovery from sedation was found to be very individual and not related to the dose administered, as assessed by a simple, easy-to-use method. There was no difference in postoperative pain between the sedated and unsedated groups, and we found no correlation between postoperative pain and amnesia. Eighty-five per cent of the patients preferred sedation during surgery, even though none of them had a preoperative indication for sedation.     

The frequency and distribution of skeletal and dental components in Class II orthognathic surgery patients

In an effort to identify the skeletal and dental relationships of Class II malocclusion, lateral cephalograms of 253 adult orthognathic surgery patients (76 male, 177 female) who had a Class II molar and cuspid relationship were traced. One hundred and four of the subjects had had presurgical orthodontic treatment and 148 had not. The most common combination of variables found in this study population was a retrusive maxilla, protrusive maxillary incisors, protrusive mandibular incisors, a retrusive mandible, and a long lower facial height.     

Comparison of sedation,amnesia, and patient comfort produced by intravenous and rectal diazepam

In a cross-over study, intravenous diazepam was compared with rectal diazepam for sedation in outpatient oral surgery. Fifty-four operations were performed on 27 patients. Recovery from sedation, experience during the postoperative course, amnesia, estimation of the sedative effect, and patient preference of method of sedation were studied. The recovery times of the sedation methods did not differ. Sedative effects after the first operation were estimated as good by 87% of patients given intravenous sedation and by 75% of those given rectal sedation. However, there was a significant relationship between the subjective experience of stronger sedative effect and preference of sedation method that favored the intravenous technique. The degree of amnesia was significantly higher during intravenous sedation, but a high degree of amnesia was not related to patients' preference for a sedation method. Neither sedation method produced any local side effects.     

Comparison of the healing and revascularization of onlayed autologous and lyophilized allogeneic rib grafts to the edentulous maxilla

The healing and revascularization of onlayed autologous and lyophilized allogeneic rib grafts to the edentulous maxilla in the Macaca fascicularis monkey were studied using clinical, histologic, and microangiographic methods at varying intervals of up to eight months. Results indicated that healing and revascularization were similar but resorption of the allografts occurred approximately three months later than resorption of the autografts. Both grafting systems appeared to have minimal osteogenic potential. Osteoinduction and the final bony augmentation obtained were less than were seen with comparable autologous and allogeneic interpositional grafts.     

Healing of interpositional allogeneic lyophilized bone grafts following total maxillary osteotomy

Healing of allogeneic lyophilized bone grafted to total maxillary osteotomy sites was studied in Macaca fasciularis monkeys using histologic, microangiographic, and autoradiographic methods. Results of the study indicate that allogeneic lyophilized grafts are slowly replaced by host bone. Revascularization around the margins of the graft becomes evident at two weeks and increases until eight weeks; a hypervascular response is still present at six months. The palatal mucosa and facial gingiva provide an adequate nutrient pedicle for interpositional allogeneic grafts.