Mandibular stability using sliding or conventional four-hole plates for fixation after bilateral sagittal split ramus osteotomy for mandibular setback.

Our aim was to compare the postoperative stability of the mandible when two different fixation methods had been used after bilateral sagittal split ramus osteotomy (BSSRO) for mandibular setback. The study included 23 patients who had two-jaw BSSRO mandibular setback at the Department of Oromaxillofacial Surgery, Korea University Guro Hospital, between January 2011 and June 2014. The first group (four-hole (control) group, n=13) comprised patients whose bony segments were fixed with conventional four-hole plates, and the second (sliding plate (experimental) group, n=10) included patients whose bone segments were fixed with sliding plates. Lateral cephalograms were taken and analysed at three time points: preoperatively (T1), and one week (T2), and 1year (T3) postoperatively. The Mann-Whitney U test was used to compare the postoperative stability of the mandible in each group. There were no significant differences between the two groups in changes in the horizontal and vertical positions of point B and pogonion postoperatively, nor were there any significant differences between them in ramal inclination and inclination of the SN plane with point B at the given time points (p=>0.05 in surgical changes in the mandible immediately after surgery and 0.397, 0.616, 0.082, 0.951, 0.901, 0.476 in postoperative changes in the mandible 1 week to 1 year after surgery). Like the conventional four-hole plate, the sliding plate can also be used to achieve stability in the fixation of mandibular bone segments after BSSRO.

Treatment of chronic osteomyelitis in Korea.

OBJECTIVE: We sought to investigate the clinical and histopathologic features of chronic osteomyelitis and its treatment in Koreans. STUDY DESIGN: A total of 49 patients (ages 11-79 years; mean, 47.3 years) were examined in this retrospective chart review. In a new treatment protocol used for 39 patients, chronic osteomyelitis of the jaws was treated by surgical intervention and 2 weeks of intravenous antibiotics, followed by 6 weeks of oral antibiotics, whereas a control group consisting of 10 patients was treated by surgery alone. Surgical therapy consisted of decortication or sequestrectomy and saucerization of the affected bone. A successful outcome was defined as the resolution of symptoms after surgery alone or after surgery and 8 weeks of antibiotic therapy. Failure was defined as a case requiring a second operation and 8 additional weeks of antibiotic therapy. RESULTS: A successful outcome was seen in 94.9% of patients on the new treatment protocol, as well as in 60% of control patients. A purulent discharge developed in 2 cases after the new treatment protocol and in 4 control cases, but the patients were treated successfully with a second operation. CONCLUSIONS: Surgery followed by antibiotic therapy for at least 8 weeks is an effective method for treating chronic osteomyelitis of the jaws.

Ameloblastoma: a clinical, radiographic, and histopathologic analysis of 71 cases.

OBJECTIVES: The purpose of this study was to compare the clinical, radiologic, and histopathologic features of 71 intraosseous ameloblastomas. STUDY DESIGN: Data with respect to the patients' ages, sex, tumor locations, and surgical treatment history, as well as the radiographic findings and number of recurrences, were analyzed. The histologic types of and radiologic findings regarding tumors with higher recurrence rates were also investigated. RESULTS: The patients' ages at biopsy ranged from 11 to 70 years (mean, 30.4 years). Thirty-nine (54.9%) of the 71 subjects were males, and 32 (45.1%) were females. Sixty-two (87.3%) of the 71 ameloblastomas were located in the mandible. Swelling was the most common symptom and was experienced by 27 (38.0%) patients. Radiographically, 42 (59.2%) of the 71 tumors were unilocular with a well-demarcated border. Of the remaining 29 cases, 14 were multilocular, 2 were of soap-bubble shape, and 13 were unknown in appearance. The most common histologic pattern was plexiform, rather than follicular or acanthomatous. Sixteen cases of ameloblastoma had developed in a cyst. The overall recurrence rate was 21.1%, and the average age of the patient at recurrence was 26.4 years. CONCLUSIONS: When the diagnosis of ameloblastoma in young people remains in doubt after clinical and radiologic examination, a biopsy is necessary. Long-term follow-up at regular intervals after surgery is also recommended.

Correlation of antibiotic prophylaxis and difficulty of extraction with postoperative inflammatory complications in the lower third molar surgery.

Our aim was to investigate the correlation among antibiotic prophylaxis, difficulty of extraction, and postoperative complications in the removal of lower 3rd molars. A total of 1222 such extractions in 890 patients between January 2010 and January 2012 were analysed retrospectively. The difficulty of extraction measured by Pederson's index, antibiotic prophylaxis with cefditoren, and postoperative complications were recorded. The difficulty of extraction was significantly associated with postoperative complications (p=0.03). There were no significant associations between antibiotic prophylaxis and postoperative complications in groups of equal difficulty ("easy" group (class I) p=1.00; "moderate" group (class II) p=1.00; and "difficult" group (class III) p=0.65). There was a small but insignificant increase in the number of dry sockets and infections in class III cases. In conclusion, this study provides further evidence that antibiotic prophylaxis for the prevention of postoperative inflammatory complications is unnecessary for extraction of 3rd molars.

New cationic liposomes for gene transfer into mammalian cells with high efficiency and low toxicity.

Novel cationic amphiphiles, based on hydrophobic cholesterol linked to L-lysinamide or L-ornithinamide, were designed and tested as nonviral gene transfer vectors. Each amide form of amino acid was conjugated to cholesterol by a carbamate ester bond to facilitate efficient degradation in animal cells. Cytotoxicity tests were performed for some cell lines. The transfection efficiency of the amphiphiles on different cell lines was evaluated as a liposomal solution in the presence of the fusogenic helper lipid, dioleoyl phosphatidylethanolamine (DOPE). The efficiency was also compared with other generally used gene carriers, such as lipofectin, 3 beta[N-(N'N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) liposome, and polyethylenimine (PEI).

Demonstration of Epstein-Barr virus in odontogenic and nonodontogenic tumors by the polymerase chain reaction (PCR).

BACKGROUND: Although considerable insight has been gamed into Epstein-Barr virus (EBV) as an important etiologic factor in various tumors, virtually little is known about the relationship between EBV genes and oral tumors. METHOD: Thirty-two cases of nonodontogenic tumor (16 squamous cell carcinomas, 11 salivary gland tumors, 1 malignant lymphoma, 1 spindle cell sarcoma, 1 osteogenic sarcoma, 1 malignant fibrous histiocytoma and 1 verrucous carcinoma), 17 cases of odontogenic tumor (17 ameloblastomas, the most important and common type of odontogenic tumor) and 12 cases of normal oral tissue (8 normal gingival tissues and other oral mucosa) were examined for the presence of EBV-DNA, with primers specific for the BamW, BNRF1, BMLF1, BamC, IR3, BMRF1, EBNA-2A BamhY, and EBNA-2B BamhY region of the EBV genome by the polymerase chain reaction (PCR). RESULTS: Fifty-three percent (17/32) of nonodontogenic tumors, forty-eight percent (8/17) of ameloblastomas, and ninety-two percent (11/12) of normal oral tissues were positive for EBV-DNA. Of the EBV-DNA, BMLF1 demonstrated the strongest reactivity in the nonodontogenic tumors, and BamC demonstrated the strongest reactivity in the ameloblastomas and normal oral mucosae. CONCLUSIONS: Taken into account with the expression of different EBV genes in odontogenic and nonodontogenic tumors, these findings suggest that even though odontogenic tumors and nonodontogenic tumors are relatively unique, the appearance of different EBV genes seems to suggest the complicated roles that the EBV genes play.

Isolation and characterization of cultured human periodental ligament fibroblast-specific cDNAs.

The molecular mechanisms that control the function of periodontal ligament (PDL) fibroblasts remain unclear. We speculated that the character of differentiating PDL fibroblasts is defined by the altered expansion of specific genes not found in neighboring gingival fibroblasts in the periodontium. To expand this set, subtractive hybridization was applied between cultured human PDL and gingival fibroblasts to identify genes differentially expressed in PDL. Consequently five candidate clones, PDLs (periodontal ligament specific) 5, -17, -22, -25, and -31 were identified and characterized by homology search, Northern analysis, and in situ hybridization. Although the mRNAs of these clones were expressed by bone marrow cells and rarely by gingival fibroblasts, the highest expression was detected in the PDL cells, which were uniformly distributed throughout the whole PDL. Amongst the five candidate clones, we focused on PDLs17, because it is a hypothetical protein whose biological function has not been reported yet in the database. Polyclonal antiserum raised against PDLs17 peptide was made, and stained the PDL fibroblasts, osteoblast-like cells and stromal cells in the bone marrow, but not gingival fibroblasts. The results suggest that clones, PDLs5, -17, -22, -25, and -31 may be used as PDL fibroblast-specific markers, and that PDLs17 could act as an important factor in the differentiation process of PDL fibroblasts.