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Purpose The purpose of this study was to evaluate the natural recovery of neurologic injury after orthognathic surgery based on subjective neurologic evaluation. Patients and Methods From December 2007 through June 2008, 47 patients (26 male, 21 female) from Seoul National University Bundang Hospital who had been treated with orthognathic surgery were identified. Subjective neurologic evaluation was performed 1 month, 3 months, and 6 months after surgery. Orthognathic surgery included bilateral sagittal split osteotomy (BSSO), BSSO plus genioplasty, BSSO plus Le Fort I, and BSSO plus Le Fort I plus genioplasty. Results Sensory changes occurred at the chin (55.7%) and lip (27.3%). Most patients reported an altered sensation when these body parts were touched. Visual analog scale (VAS) pain scores were 1.63 ± 1.89 (1 month postoperatively), 0.92 ± 1.34 (3 months postoperatively), and 0.95 ± 1.60 (6 months postoperatively); these values were not significantly different. VAS scores for altered sensation were 5.40 ± 2.83 (1 month postoperatively), 4.00 ± 2.35 (3 months postoperatively), and 3.36 ± 2.89 (6 months postoperatively). These differences were significant. For each surgery, the VAS of paresthesia decreased as time elapsed. The VAS of the altered sensation differed significantly after 1 month, 3 months, and 6 months whether or not genioplasty was performed. Conclusions The results indicated that the altered sensation that may develop after orthognathic surgery is an unavoidable complication. Nevertheless, with time, the condition may resolve spontaneously. In patients who underwent simultaneous genioplasty, the incidence of altered sensation was high but was not significantly associated with the age of the patient or the performance of simultaneous maxillary surgery.

Purpose The purpose of this study was to evaluate the injury and recovery of the inferior alveolar nerve in orthognathic patients at 1 and 4 weeks after surgery using electronic thermography. Materials and Methods Twenty subjects with Class III dentofacial deformity were studied. All patients underwent bilateral sagittal split ramus osteotomy. To image the temperature of the face, 1 anteroposterior view and 1 lateral view were taken from both the right and left sides. Similar images were taken at 1 and 4 weeks after surgery. The control was the presurgical temperature of the 20 patients who showed unilateral or bilateral nerve damage after surgery. Results In the patients with unilateral nerve damage (n = 14), on the anteroposterior views, the temperatures of the mentum on the 2 sides differed by 0.64°C at 1 week after surgery, and the difference decreased to 0.23°C at 4 weeks after surgery. On the lateral images, the differences in temperature between the mentum areas were 0.10°C at 1 week and 0.27°C at 4 weeks after surgery. In the patients with bilateral nerve injury (n = 6), on the anteroposterior views, the temperatures of the mentum on the 2 sides differed by 0.20°C at 1 week after surgery and 0.13°C after 4 weeks. On the lateral views, the differences were 0.18°C at 1 week and 0.34°C at 4 weeks after surgery. Using the repeated measurement analysis method, the anteroposterior view showed statistically significant results in the patients with unilateral nerve damage. Conclusion The infrared body temperature method is an objective method that can be applied as a supplemental diagnostic method for inferior alveolar nerve injury.

Objectives Dental lasers have been used for uncovering submerged implants as well as decontaminating implant surfaces when treating peri-implantitis. The objective of this study was to compare the possible alterations of the smooth surface and resorbable blast material (RBM) surface implants after using NdYAG and CO2 lasers at various energies. Materials and Methods Ten smooth surface implants and 10 RBM surface implants were used. Two smooth surface implants and 2 RBM surface implants served as a control group that was not lased. The remaining implants were treated using NdYAG and CO2 lasers. The surface of each implant was treated for 10 seconds on the second and third threads. The smooth surface implants (group 1) were treated using a pulsed contact NdYAG laser at power settings of 1, 2, 3.5, and 5 W, which are commonly used for soft tissue surgery; the corresponding energy and frequency were 50 mJ and 20 Hz, 100 mJ and 20 Hz, 350 mJ and 10 Hz, and 250 mJ and 20 Hz, respectively. The group 2 RBM implants were treated using a pulsed contact NdYAG laser. The group 3 smooth surface implants were treated using a pulsed wave non-contact CO2 laser at 1, 2, 3.5, and 5 W, and the group 4 RBM implants were treated using a pulsed wave non-contact CO2 laser. Data were analyzed using scanning electron microscopy. Results The control surface was very regular and smooth. After NdYAG laser treatment, the implant surface showed alterations of all the surfaces. The amount of damage was proportional to the power. A remarkable finding was the similarity of the lased areas on the smooth and RBM surfaces. CO2 laser at power settings of 1.0 or 2.0 W did not alter the implant surface, regardless of implant type. At settings of 3.5 and 5 W, there was destruction of the micromachined groove and gas formation. Conclusion This study supports that CO2 laser treatment appears more useful than NdYAG laser treatment and CO2 laser does not damage titanium implant surface, which should be of value when uncovering submerged implants and treating peri-implantitis.

Purpose Our goal was to report on tooth ash and plaster of Paris mixture in bone defects in an ovariectomized rat osteoporosis model. Materials and methods Sixty rats were randomly assigned to 4 groups and each group was further divided into 3 subgroups: 4, 8, and 16 weeks after implantation. The defect was filled with different grafting conditions as follows: group 1, ovariectomy and nongraft group; group 2, ovariectomy and tooth ash-plaster graft group; group 3, nonovariectomy and nongraft group; and group 4, nonovariectomy and tooth ash-plaster graft group. Histologic sections and histomorphometric analysis of defects were obtained 4, 8, and 16 weeks after surgery. Results For the 4-week ovariectomy group, there was significantly greater bone formation in tooth ash-plaster group compared with the nongraft group. In the nonovariectomy group, the tooth ash-plaster group also showed better bone formation than the nongraft group. However, there was no statistical significance. In both the ovariectomy and nonovariectomy groups, a significant increase in bone formation was observed according to the elapse of time. The nonovariectomy group showed increased new bone formation compared with the ovariectomy group, with the tooth ash-plaster group showing statistical significance in each subgroup ( P = .048). Conclusions Ovariectomy acts as a negative factor in new bone formation. For a critical size bony defect, the tooth ash-plaster treatment of the osseous defect produces more stable, effective, and rapid new bone formation.

Purpose This study evaluated the effect of high local concentrations of antibiotics on bone repair induced by demineralized bone in rats. Materials and methods Seventy-two 3-week-old rats, weighing 200 to 300 g, were used for the experiment. Rats were divided into 4 groups: control group (group 1), saline-impregnation group (group 2), gentamicin-impregnation group (group 3), and tetracycline-impregnation group (group 4). The rats were killed at 3, 8, and 12 weeks after surgery. Samples were stained with hematoxylin-eosin and subjected to the histomorphometric analyses. Results There were significant differences in new bone formation among groups at all time periods. Comparing differences between groups at each time point, significantly more new bone formation was present in group 2 than in group 1 at 3 weeks, more in group 2 than in group 1 and more in group 2 than in group 4 at 8 weeks, and the most in group 2 among all groups at 12 weeks. In terms of the time period, significantly more new bone formation was observed at 8 weeks during the time period between 3 and 8 weeks, and at 12 weeks during the time period between 3 and 12 weeks. Conclusions Our result suggests that the bone graft material is most effective when mixed with saline for the regeneration of osseous defects.

Purpose This study examined immunohistochemical changes in the craniomandibular joints of rabbits after distraction osteogenesis following mandibular corticotomy. Materials and methods The experimental animals (n = 8) were divided into 3 groups that underwent 2, 3.5, and 5 mm of unilateral distraction osteogenesis (groups 1, 2, and 3, respectively). After corticotomy of the left mandibular body and a 7-day healing period, a second operation was performed to expose the device. Distraction was then performed at the rate of 0.5 mm/d. A 14-day consolidation period was allowed after the distraction was complete. Changes in cartilage, osteoblast activity, and osteoclast activity were then examined. Results The differentiation and proliferation of cartilage increased in groups 1 and 2, were highest in group 2, and decreased in group 3. Group 2 also showed the greatest increase in the width of the hypertrophic chondrocyte layer. Relative to the control group, osteoclast activity was only somewhat higher in groups 1 and 2 but was significantly higher in group 3. Osteoblast activity was significantly higher in groups 1 and 2 than in the control group. However, the osteoblast activity in group 3 was slightly lower than that in group 2. At the time of unilateral mandibular distraction, no degenerative changes of the temporomandibular joint were observed in groups 1 or 2, but bone resorption was observed in group 3. Conclusions The unilateral mandibular distraction of 2 or 3.5 mm was acceptable in that no degenerative changes of the temporomandibular joint were observed on either the distraction or the nondistraction sides. Five millimeters of distraction might be beyond physiologic limits.

A 21-year-old man was admitted to the Department of Oral and Maxillofacial Surgery, Chosun University Dental Hospital, on January 14, 2000. A clinically asymptomatic radiolucent region in the body of the mandible was discovered on the panoramic radiograph during routine examination. His medical history was unremarkable, and he was taking no medications. His social history was negative for alcohol, tobacco, or drug abuse. He lived at home with his parents and healthy siblings. The family history was noncontributory. The panoramic radiograph showed 2 expansile radiolucencies in close proximity to a mesioangularly, partially embedded mandibular third molar: 1 on the distal aspect and the other anterior to the tooth and in the apical region of the first and second right mandibular molars. The posterior region, which had a thin cortical border, was oval in shape, extending upward into the middle portion of the mandibular ramus. The lower one had well-demarcated margins, was elliptical in shape, and extended to the lower border of the mandible without causing tooth displacement or resorption (Fig 1). An occlusal radiograph showed buccal expansion and a thinned cortex on the anterior radiolucency. The initial diagnosis of the 2 regions was odontogenic keratocysts, but a computed tomogram (CT) of the anterior expansile radiolucency showed a bony defect in the lingual cortex (Fig 2). Furthermore, the soft tissue in the anterior lesion appeared to have a density between fat and muscle. The contents of the posterior expansile radiolucency appeared to contain semifluid. On this basis, a diagnosis of ameloblastoma was made.

Although small cell carcinoma generally occurs in the lung, it has been recognized in extrapulmonary sites. Primary lesions in oral cavity are very rare. The tumor has a high recurrence rate and low survival rate because of its aggressive growth pattern and tendency to develop distant metastases. Methods such as surgery, chemotherapy, radiation, or a combination of these modalities, have been used to increase the therapeutic efficacy. The following report describes a case of small cell carcinoma that was discovered in an extraction socket. The clinical, histologic, and immunohistochemical features are presented.

Purpose: This article reports the authors' experience with the use of the tongue flap for intraoral soft tissue reconstruction. Patients and Methods: From May 1992 to December 1996,16 patients were treated with a tongue flap for reconstruction of a variety of intraoral soft tissue defects. Ages ranged from 16 to 65 years with a mean of 39.6 years. Results: The procedure was successful in 15 patients. There were six complications: one total necrosis, four partial necroses, and one infection. Partial necrosis and infection were well controlled by conservative treatment. Conclusion: Use of the tongue flap is a versatile method for reconstruction of a variety of intraoral soft tissue defects.