• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권4호
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• pp.308-313
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• 2001

The purpose of this study is to validate the potential etiologic factors for temporomandibular disorder(TMD). TMJ arthroscopic examination was performed in upper joint compartment of 32 joints from 20 patients with mandibular fractures. Synovial fluid was collected from the upper joint space during pumping manipulation with normal saline. Cytologic smearing and histomorphologic exam of synovial fluid were performed in 15 joints. Prostaglandin $E_2(PGE_2)$ concentration was measured in 11 joints. Leukotriene $B_4(LTB_4)$ concentration was measured in 8 joints. There were several arthroscopic variables such as ecchymosis, fibrillation, and adhesion. Histomorphologic exam showed a variety of findings such as bloody smears, cellular cluster, degenerated cells and cartilage, undifferentiated crystal. Mean $PGE_2$ concentrations were 316.5 pg/ml. Mean LTB4 concentrations were 45.9pg/ml. This study demonstrated a variety of findings on inflammatory and degenerative changes of TMJ. Because acute trauma such as mandibular fracture is a major etiologic factor in cartilage degradation and biochemical and intraarticular pathology, clinicians must identify and address TMJ signs and symptoms during follow-up periods in the long term.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권4호
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• pp.353-357
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• 2001

The techniques of the dental treatment are well known to common people, but the dental implant as one of the treatment options to rehabilitate patient's mouth is little known to them. Taking these situation into consideration, we, writers made actual analyses of statistics by putting into the form of diagrams based on questionnaires. Three hundreds of common people over 20 years old were picked up and we used convenience sampling method which is one of nonprobability sampling methods. Statistics are about these questions. 1. How much common people know about dental implant as a treatment option. 2. How much common people know about the detailed portions of the dental implant for rehabilitaton. 3. How common people got to know the dental implant. We present actual answers of the common people.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권4호
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• pp.301-307
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• 2001

There have been many trials to decrease the scar formation followed by wound treatment. $TGF-{\beta}$ plays a important role on wound healing in adult. Therefore the repression of $TGF-{\beta}$ expression will be helpful to decrease scar formation. Decorin is known to competitively inhibit $TGF-{\beta}$ expression. Decorin were subcutaneously administered in surgical wounds in rabbits to investigate the preventing effect of scar formation for clinical application. Histologic findings of wound healing progresses is similar with control and experimental group at 2week. $2.5{\mu}g$ decorin of administrated group was similar to those of control group at 4 and 8week. In wound healing process $10{\mu}g$ decorin of administrated groupsat showed that thickness of immature collagen fibers(scar) was decreased as compared with control group at 4, 8 weeks. $20{\mu}g$ decorin of administrated group showed similar histologic features to $10{\mu}g$ administrated group. The wounds of 8week experimental group(10, $20{\mu}g$) were completely recovered to the normal surrounding skin tissue including sweat gland and hair follicle. These results suggested that decorin can be of help to the prevention of local scar formation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.406-413
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• 2004

Progress in medical science and cell biology has resulted in the transplantation of human cells and tissues from on human into another, facilitating reproduction and the restoration of form and function, as well as enhancing the quality of life. For more than 40 years, society has recognized the medical and humanitarian value of donation and transplanting organs and tissues. The standard operating procedures of hard tissues reflect the collective expertise and conscientious efforts of tissue bank professionals to provide a foundation for the guidance of tissue banking activities. Procurement of allograft tissues from surgical bone donors is a part of tissue banking. During the past decades the use of bone allografts has become widely accepted for the filling of skelectal defects in a variety of surgical procedures. In particular in the field of orthopaedic and oral and maxillofacial surgery the demand for allografts obtained from either living or post-mortem donors has increased. Hospital-based tissue banks mainly retrieve allografts from living donors undergoing primary total hip replacement for osteoarthritis or hemi arthroplasty for hip fractures and orthgnatic surgery such as angle reduction. Although bone banks have existed for many years, the elements of organized and maintaining a hospital bone bank have not been well documented. The experience with a tissue bank at Korea Tissue Bank(KTB) between 2001 and 2004 provides a model of procurement, storage, processing, sterilization and documentation associated with such a facility. The following report describes the standard operating procedures of hard tissues such as femoral head obtained from living donors.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.368-379
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• 2004

Distraction osteogenesis is a biologic process of new bone formation between the surfaces of bone segments that are gradually separated by incremental traction. Distraction osteogenesis is clinically applied as a new treatment modality of mandibular hypoplasia or bony defect area in maxillofacial area by many studies of distraction devices and method. But disadvantage of distraction osteogenesis shows unfavorably long consolidation period and relapse tendency. Therefore. this experiment was designed to investigate the effectiveness of combined application of distraction and compression force for improving of bone quality and shortening of treatment period during distraction osteogenesis. Twenty-one Sprague-Dawley rats with $300{\sim}350gm$ were used. These were divided into two group as distraction group and combination group was applied with compression force in the consolidation period. The rat were sacrificed for gross finding, radiographic and histologic findings. at 2, 4 weeks after distraction. The result were follow : 1. On radiographic finding, all experimental groups appeared more radiopacity than control groups both at 2, 4 weeks after distraction. 2. On histologic finding, trabeculae of bone and mature lamellar bone were showed increasingly in experimental group. Ossification occured rapidly. From this study, we may suggest that compression force application in consolidation period during distraction osteogenesis can be useful method improve bone quality and to shorten the treatment period. But more experimental and clinical studis are necessitated on effects of compression force application during distraction osteogenesis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.391-399
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• 2004

Distraction osteogenesis has been thought to be promising technique for replacing bone graft in maxilla and mandible. The purpose of this study was to investigate the expression of osteonectin on distraction osteogenesis. Sixteen rabbits were used for this experiment. Osteotomy was performed between premolar and mental foramen. On the experimental group, distraction device was connected to the respective bone segments. On the control group, bone segments were fixed using plate and screws after osteotomy. Distraction was carried out at the rate of 0.7mm per day to obtain a 4.9mm elongation on the experimental group. After 3 days, 7 days, 14 days, and 28 days two rabbits of each group were sacrificed. The results obtained from this study were as follow : Experimental group was observed that the gaps between the distracted bone edges were occupied by new bone. Expression of Osteonectin were detected throughout the experiment in both groups and Expression of Osteonectin were markedly increased during distraction and consolidation period in experimental group than control group. From these results, it could be stated that distraction was shown to improve and accelerate bone formation and mechanical stress like distraction has considerable effects on osteonectin.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.438-443
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• 2004

Objectives : The proper development of the facial structures relies upon a sequence of tightly regulated signaling interactions between the ectoderm and mesoderm involving the participation of several families of signaling molecules. Among these, bone morphogenetic proteins (BMPs) have been suggested to be a key signal that regulates the development of the mandible and the initiation and morphogenesis of the teeth. The aim of this study was to examine the artificial development of the mandibular structures and to examine the role of BMPs on tooth morphogenesis and differentiation using an organ culture system. Materials and Methods : The tooth germs from Ed 11.5, 13.5 mice were dissected, and transplanted into the diastema of the mandible primordia. The mandibles containing the transplanted tooth germs were cultured in vitro. During this period, beads soaked with BMP4 were implanted around the transplanted tooth germs. In addition, a diastema block containing the transplanted tooth germ was dissected, then transferred to an adult mouse kidney. After the organ culture, the developing mandibular explant was removed from the kidney and prepared for the tissue specimens. Odontogeneis of the transplanted tooth germs was examined after Hematoxylin-eosin, Masson-trichrome staining. Results : Proliferation and differentiation of the tooth germs cultured in the diastema was observed. In the BMP4-treated tooth germs, the formation of the first and second molars was noted. The crown of the developing tooth showed the formation of a mature cusp with the deposition of enamel and dentin matrix. In conclusion, it was confirmed that BMP4 is involved in the formation of a dental crown and the differentiation of ameloblasts and odontoblasts of the molar tooth during the development of the transplanted tooth germs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.359-367
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• 2004

Purpose: After the surgical correction with sagittal split ramus osteotomy, the position of the mandibular condyle in the glenoid fossa and the proximal segment of the mandible change because of bony gap between proximal and distal segment, especially in case of mandibular setback asymmetrically. In this study, positional changes in the condyle and proximal segment after BSSRO were estimated in the mandibular asymmetry patient by analyzing the in submentovertex view and P-A cephalogram for identification of ideal condylar position during surgery. Patients and Methods: The 20 patients were selected randomly who visit Dankook Dental Hospital for mandibular asymmetry. Bilateral sagittal split ramus osteotomy with rigid fixation was performed and P-A cephalogram and submentovertex view was taken at the time of preoperative, immediate postoperative, 3 month postoperative period. Results: Intercondylar length and transverse condylar angle was increased due to inward rotation of proximal segment and anteromedial rotation of lateral pole of condyle head. The condylar position had a tendency to return to the preoperative state and after 3 months return up to about half of the immediate post-operative changes, and all the results showed more changes in asymmetry patient and deviated part of the mandible. Conclusion: Based on all these results above, surgeon should make efforts to have a precise preoperative analysis and to have a ideal condylar position during rigid fixation after BSSRO.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권5호
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• pp.380-390
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• 2004

Bone healing plays an important role in orthognathic and craniofacial surgery. Bone tissue repair and regeneration are regulated by an array of growth and morphogenetic factors. Bone formation and remodeling require continuous generation of osteoprogenitor cells from bone marrow stromal cells, which generate and respond to a variety of growth factors with putative roles in hematopoiesis and mesenchymal differentiation. In this study, the efficacy of a single application of hepatocyte growth factor to promote bone regeneration in 5-mm experimental calvarial defects of adult male rats was assessed histologically and immunohistochemically. The result of the experimental site were compared with those of the contralateral contral side. None of the control and experimental bone defects demonstrated complete bone closure. Bone regeneration was found close th the margine and central part of the defects. At 1, 2 weeks, there were found much significant cellural mitotic activity and many inflammatory cells and osteoblasts on the experimental site than control site. At 4, 6 weeks, new bone apposition was founded in both site but, more apposition was seen at experimental site. At 8, 12 weeks, also, some differences was found that more apposition of new bone and collagen fiber was seen on experimental site. Our results have some possibility that HGF do a early positive role to repair the bone defect. More study will be needed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.482-487
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• 2004

Aims: This study was designed to determine the incidence of altered sensation in patients undergoing orthognathic surgery. Method: Seventy two patients who underwent orthognathic surgery between January, 1999 and December, 1999 constituted the study group. Seven patients were excluded because of lack of follow up. Sixty five patients were followed using objective and subjective neurologic testing during the period immediately following operation, 1 month, 2 months, 6 months, and 1 year postoperatively. Age ranged from 17 to 38 years, with a mean of 24.5 years. Male patients were 21, female 44. Twenty eight bilateral sagittal splitting ramus osteotomy(BSSRO) of mandible were performed, 35 BSSRO with genioplasty, 2 genioplasties. Information on the degree of intraoperative nerve encounter was obtained from the surgical reports in 47 patients and was divided into the following three categories: (1) the nerve was not encountered in 23 patients; (2) the nerve was exposed in 11 patients; (3) the nerve was exposed and repositioned from the proximal segment in 13 patients. Results: Four patients reported altered nerve sensation of lower lip and/or chin(6.2%) at final follow up. Two patients underwent BSSRO and the other two patients BSSRO with genioplasty. Three of the patients underwent nerve exposure during the operation. Conclusion: We suggest that the nerve exposure during the operation might be partly responsible for nerve dysfunction after orthognathic surgery.