The purpose of this study was to verify the split-crest technique experimentally for successful implantation at alveolar bone having unfavorable condition. Using inferior border of the mandible of the canine, we made comparable study about the state of osseointegration between conventional technique and split-crest technique. We set experimental group which was implanted at inferior border of the mandible of the canine by split-crest technique using the fixture of 3.75 mm width and 8mm length, and set control group which was implanted by conventional technique at the counter area of the mandible. The experimental animal was sacrificed at 1, 4, 8 and 16 week. We observed the changing process of bone formation following implantation with stereoscopy, light microscopy, electron microscopy and fluorescent microscopy, and studied histomorphometrically. Histologic results were as follow : 1. In control group, a bit of new bone formation was initiated on a portion of bone defect area at 1 week. The initiation of osseointegration between fixture and new bone was seen at 4 week. New bone tissue with normal shape and structure formed and filled defect area at 8 week. But complete bone remodeling was attained at 16 week. 2. In experimental group, bone formation around fixture was going on actively. But the shape and structure of new bone area was more irregular than that of control group, and bone density was also lower than that of control group. Active new bone formation was still observed at 16 week. 3. The osseointegrated new bone was remodeled to cancellous bone having trabeculae and marrow space composed of compact lamellar bone. 4. In fluorescent microscopic analysis, active bone formation was seen between 4 weeks and 8 weeks at control group. Otherwise, along the all experimental period new bone formation was observed evenly at experimental group. 5. Both control and experimental group, normal osseointegration was accomplished without bone resorption which is essential factor in split-crest technique. As previous results, when implantation using split-crest technique at alveolar bone attenthaving unfavorable condition, early bone formation was delayed slightly, but we could get attentive results along the long term period.
Animals ; Bone and Bones ; Bone Density ; Bone Marrow ; Bone Remodeling ; Bone Resorption ; Mandible ; Microscopy ; Microscopy, Electron ; Osseointegration* ; Osteogenesis

No abstract available.
Humans ; Orthognathic Surgery ; Prognathism

No abstract available.
Mandibular Osteotomy*

No abstract available.
Skeleton

No abstract available.
Giant Cells ; Gingiva ; Granuloma, Giant Cell ; Osteomalacia

Treatment of oral cancers with chemotherapeutic agents are evaluated as an effective method for remission to reduce cancer proliferation nowadays. But, minimization of side-effects such as bone marrow suppression, gastrointestinal toxicity and renal damage is another problem to be solved. Thus, a possible approach to develop a clinically applicable chemotherapeutic agents is to screen anticancer activity among traditional medicinal plants which have been used for thousands of years with very low side-effects in orient. In this study we focused on screening anti-oral cancer activities among 14 traditional medicinal plant extracts that revealed anticancer activities on other solid tumors. The results were as follow: 1. Methanol extract of Lepidium apetalum showed the highest anti-oral cancer activity against A253 cells. At concentration of 4 microgram/ml, the cell viability was 48% under our experimental condition. IC50 value obtained was 4 microgram/ml. 2. Methanol extract of Coptis japonica and Solanum nigrum were effective on KB cells. Cell viability observed were 62% and 67% at concentration of 4 microgram/ml, and IC50 values were 12 microgram/ml and 10 microgram/ml respectively. 3. When the methanol extract of Lonicera caerule was combined with 2 microgram/ml of cisplatin, the anticancer activity was synergistically increased. One hundred microgram/ml of Lonicera caerule showed 92% (alone) or 59% (combined with cisplatin) cell viabilities. IC50 value of Lonicera caerule extract against KB cells was reduced from 301 microgram/ml to 126 microgram/ml when combined with 2 microgram/ml of cisplatin. 4. Medicinal plant extracts effective on both A253 and KB cells were Coptis japonica, Lepidium apetalum, Solanum nigrum, Caesalpiniae Lignum, Curcuma aromatica.
Bone Marrow ; Caesalpinia ; Cell Survival ; Cisplatin ; Coptis ; Curcuma ; Humans ; Inhibitory Concentration 50 ; KB Cells ; Lepidium ; Lonicera ; Mass Screening ; Methanol ; Mouth Neoplasms ; Plants, Medicinal* ; Solanum nigrum

No abstract available.
Adenoma, Pleomorphic ; Mouth Mucosa

For the study of its stability when the screw has been fixed after sagittal split ramus osteotomy(SSRO) of the mandible, the methods of screw arrangement are classified into two types, triangular and straight. The angles of screws to the bone surface are classified as perpendicular arrangements, the 60degrees anterioinferior screw, known as triangular, and the most posterior screw, called straight arrangement, thus there are four types. The finite element method model has been made by using a three dimensional calculator and a supercomputer. The load directions are to the anterior teeth, premolar region, and molar region, and the bite force is 1 Kgf to each region. The distribution of stress, the von-Mises yield strength, and safety of margin refer to the total sum of transformed energy have been studied by comparison with each other. The following conclusion has been researched : 1. When shear stress is compared, in the triangular arrangement in the form of "giyeok", the anterosuperior screw is seen at contributing to the support of the bone fragment. In the straight arrangement, substantial stress is seen to be concentrated on the most posterior angled screw. 2. When the von-Mises yield strength is compared, it seemed that the stress concentration on the angled anteroinferior screw is higher, it shows a higher possibility of fracture than any other screw. In the straight arrangement, stress appeared to be concentrated on the most posteriorly angled screw. 3. When the safety margins of the transfomed energy are compared, the energy conduction is much greater in the case of the angled screw than in the case of the perpendicular screw. The triangular arrangement in the form of "giyeok" shows a superior clinical sign to that of the straight arrangement. Judging from the above results, when the screw fixation is made after SSRO in practical clinical cases, two screws should be inserted in the superior border of mandibular ramus and a third screw of mandibular inferior border should be inserted in the form of triangular. All screws on the bony surface should be placed perpendicularly-90 degrees angles apparently best promote bony support and stability.
Bicuspid ; Bite Force ; Mandible ; Molar ; Osteotomy, Sagittal Split Ramus* ; Tooth

Treatment of oral cancers with chemotherapeutic agents are evaluated as an effective method for remission to reduce cancer proliferation nowadays. But, minimization of side-effects such as bone marrow suppression, gastrointestinal toxicity and renal damage is another problem to be solved. Thus, a possible approach to develop a clinically applicable chemotherapeutic agents is to screen anticancer activity among traditional medicinal plants which have been used for thousands of years with very low side-effects in orient. In this study we focused on anti-oral cancer activities of momordin, which was medicinal plant extracts that was revealed anticancer activities, on KB cell(oral cancer cell). The results were as follow : 1. Momordin showed the excellent anti-oral cancer activity against KB cells. Obtained IC50 value of Momordin was 10.4 microgram/ml. 2. When KB cells were treated with Momordin, dose and time dependent DNA fragmentation of KB cells were observed. DNA fragmentation was initiated on three days at the concentration of 20 microgram/ml Momordin. 3. Flow cytometry showed dose-dependent apoptotic cell increase of KB cells on Momordin. 18.55% apoptotic cell were observed up to 72 hours at the concentration of 20 microgram/ml of Momordin 4. Momordin induced nonspecific apoptosis without specific cell cycle arrest. 5. Through MTT assay, DNA fragmentation assay and flow cytometric analysis. anticancer effect of Momordin against KB cell was induce of apoptotic cell death.
Apoptosis ; Bone Marrow ; Cell Cycle Checkpoints ; Cell Death ; DNA Fragmentation ; Flow Cytometry ; Humans ; Inhibitory Concentration 50 ; KB Cells ; Mouth Neoplasms ; Plants, Medicinal

No abstract available.
Facial Bones*