A Multicenter Retrospective Study of Outpatient Intravenous Sedation for Dental Treatments

The effects of beta-TCP/rhBMP-2 on bone formation in osteoblast-like cells induced from bone marrow-derived mesenchymal stem cells

The present study aimed to investigate the osteogenic potentials of differentiated osteoblast-like cells (DOCs) induced from bone marrow-derived mesenchymal stem cells (MSCs) on beta-tricalcium phosphate (beta-TCP) with recombinant human bone morphogenetic protein (rhBMP-2) in vitro. Osteoblast differentiation was induced in confluent cultures by adding 100 nM dexamethasone, 10 mM beta-glycerophosphate, 50 mM L-ascorbic acid. The Alizarin red S staining and reverse transcriptase-polymerase chain reaction (RT-PCR) were perfomed to examine the mRNA expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OCN), receptor activator for nuclear factor kappaB ligand (RANKL), runt-related transcription factor 2 (RUNX2), collagen-I (COL-I). There were no significant differences in the osteogenic potentials of DOCs induced from MSCs on beta-TCP(+/-). According to the incubation period, there were significant increasing of Alizadin red S staining in the induction 3 weeks. The mRNA expression of ALP, RUNX2, and RANKL were higher in DOCs/beta-TCP(-) than DOCs/beta-TCP(+). According to rhBMP-2 concentrations, the mRNA expression of BSP was significantly increased in DOCs/beta-TCP(+) compared to that of DOCs/beta-TCP(-) on rhBMP 10 ng/ml. Our study presented the beta-TCP will have the possibility that calcium phosphate directly affect the osteoblastic differentiation of the bone marrowderived MSCs.

The BMPs expression and histomorphometric study of beta-TCP /rhBMP-2 Grafting on the rabbit cranial bone defects

OBJECTIVE: The Purpose of the study was to investigate the bone morphogenic protein expression of rhBMP-2(recombinant human bone morphogenic protein-2) as singnaling molecule and beta-TCP(Tricalcium phosphate) as a bone substitute and carrier medium of rhBMP-2. MATERIALS AND METHODS: 16 rabbits divided into 2 group of each 8 rabbit. Two standardized bone defect, round bilateral defect was made in the cranium of the 8 rabbit of first group, and was grafted with 150~500micrometer diameter beta-TCP 0.25g in one side, which was soaked with rhBMP-2, and autogenous bone was grafted on another side as a positive control. Second group of 8 rabbit, only beta-TCP was grafted with same size and same manner. After 2, 4, 8, and 12 weeks, specimen was taken for microscopic immunohiostochemical and histomorphometric analysis. RESULT: Grafting beta-TCP with rhBMP show the early formation of the bone regenerative factor (BMP-4) and more quantity of new bone formation than only use of beta-TCP (8,12 week), even show less new bone formation than autogenous bone. CONCLUSION: The experimental study result that beta-TCP graft combination with rhBMP-2 as a delivery system is an effective with osteoinductive capacity and biodegradable properties, so that provide clinical availibility of composite use in reconstruction of bony defect.

The mRNA expression of MMP-1, TIMP-1, TGF-beta1 in gingival keratocytes from gingival hyperplasia induced by cyclosporine A

PURPOSE: Cyclosporine A (CsA) is a versatile immunosuppresive agent used to prevent graft rejection syndrome and treat autoimmune disease. One of the major side effects associated with CsA is the abnormal gingival hyperplasia. The purpose of this study was to investigate the relationship between the mRNA expression of the MMP-1, TIMP-1, and TGF-beta1 and the concentration of CsA in cultured human gingival keratinocytes. MATERIALS AND METHODS: Gingival keratocytes were obtained from gingival tissues of 4 healthy donors. The cultured gingival keratocytes were incubated with increasing concentrations of CsA (0-2000 ng/ml) for 24 hours and the expression of MMP-1, TIMP-1, and TGF-beta1 were determined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The expressions of MMP-1 and TGF-beta1 were not significantly different according to the concentrations of CsA. The expression of TIMP-1 was significantly increased at the CsA concentration of 500 ng/ml. CONCLUSION: We concluded that the gingival hyperplasia induced by CsA was more related with TIMP-1 than MMP-1 or TGF-beta1 on gingival collagen metabolism in patients treated with CsA.

The experimental study of the bone regeneration on rabbit maxillary sinus grafting with beta-TCP

PURPOSE:Maxillay sinus grafting is an effective treatment procedure to improve bone height in the posterior maxillar area for implant installation. Beta-tricalciumphosphate(beta-TCP) was introduced to be grafting substitute material, providing a reasonable bio-degradation time, no need for harvesting procedure. The purpose of this study is to evaluate bone healing and regeneration phase using histomorphometric and immunohistochemical analysis. MATERIAL AND METHODS:Sixteen rabbits were divided into 4 groups. Bi-lateral maxillary sinus membranes were elevated at each rabbits, beta-TCP was augmented in left sinus, autogenous bone was augmented in right sinus. The rabbits were sacrificed at 2, 4, 8 and 12 weeks. We investigated the bone regeneration and growth factor expression. RESULTS: 1. The mean new bone volume formation was 28.99+/-6.55%, 49.54+/-5.47%, 69.09+/-8.90% in autogenous grafted area, and 22.86+/-5.56%, 24.00+/-4.09%, 34.11+/-3.37% in beta-TCP area at 4, 8, 12 weeks. Therefore, new bone formation in autogenous bone was significantly higher than beta-TCP (p<0.05). 2. The BMP 2/4 expression in autogenous bone grafted area was higher at 4, 8 weeks. 3. There was no difference in expression pattern of BMP-7/PDGF/VEGF during grafted bone regeneration. CONCLUSION:The authors we conclude that the autogenous bone graft was faster than beta-TCP in bone regeneration, and the BMP 2/4 were more important in graft bone regeneration.

The experimental study of the bone regeneration on rabbit maxillary sinus grafting with beta-TCP

PURPOSE:Maxillay sinus grafting is an effective treatment procedure to improve bone height in the posterior maxillar area for implant installation. Beta-tricalciumphosphate(beta-TCP) was introduced to be grafting substitute material, providing a reasonable bio-degradation time, no need for harvesting procedure. The purpose of this study is to evaluate bone healing and regeneration phase using histomorphometric and immunohistochemical analysis. MATERIAL AND METHODS:Sixteen rabbits were divided into 4 groups. Bi-lateral maxillary sinus membranes were elevated at each rabbits, beta-TCP was augmented in left sinus, autogenous bone was augmented in right sinus. The rabbits were sacrificed at 2, 4, 8 and 12 weeks. We investigated the bone regeneration and growth factor expression. RESULTS: 1. The mean new bone volume formation was 28.99+/-6.55%, 49.54+/-5.47%, 69.09+/-8.90% in autogenous grafted area, and 22.86+/-5.56%, 24.00+/-4.09%, 34.11+/-3.37% in beta-TCP area at 4, 8, 12 weeks. Therefore, new bone formation in autogenous bone was significantly higher than beta-TCP (p<0.05). 2. The BMP 2/4 expression in autogenous bone grafted area was higher at 4, 8 weeks. 3. There was no difference in expression pattern of BMP-7/PDGF/VEGF during grafted bone regeneration. CONCLUSION:The authors we conclude that the autogenous bone graft was faster than beta-TCP in bone regeneration, and the BMP 2/4 were more important in graft bone regeneration.

The effect of pulsed electromagnetic fields on beta-TCP graft in rabbit cranial bone defect

The purpose of this research was to investigate whether pulsed electromagnetic field (PEMF) stimulation applied to the rabbit cranial defects grafted with beta-tricalcium phosphate (beta-TCP) could affect the new bone formation. With 16 New Zealand white rabbits under the same condition, bilateral calvarial bone defects were formed around the sagittal suture line. The defect on the left side was grafted with beta-TCP, while on the right side was grafted by harvested autogenous bone. PEMF was applied to 8 rabbits for 8 hours per day. The bony specimen were divided into 3 groups, the group 1 was autogenous bone grafted specimen, the group 2 was beta-TCP grafted with PEMF, and the group 3 was beta-TCP grafted without PEMF. We investigated the bone regeneration and growth factor expression at 2, 4, 6, and 8 weeks. As a result, BMP 2 was expressed in the group 1 from 2 weeks, the group 2 from 4 weeks, and the group 3 from 6 weeks. BMP 4 was expressed in the group 1 from 2 weeks, in the group 2 and the group 3 from 4 weeks. 4. There was no significant difference in expression pattern of BMP 7, PDGF, VEGF, and TGF-beta1 during grafted bone regeneration in group 1, 2, and 3. According to our results, PEMF stimulation could be effective on the new bome formation in animal study, and have a feasibility of clinical use.

The effect of prp on the bone regeneration of beta-tcp grafted in rabbit cranial bone defect

The growth factors expression of cyclosporine induced gingival overgrowth

The study of efficiency of corticotomy in treatment of bimaxillary protrusion

Clinical study of odontogenic maxillary sinusitis

No abstract available.

A STATISTICAL STUDY ON FACIAL BONE FRACTURES OF KOREANS

For the establishment of the basis of treatment and study in the patients of facial bone fracture, we performed a clinico-statistical study about 28 papers and 9564 cases reported as facial bone fractures in the journal of Korean association of oral and maxillofacial surgeons, the journal of the Korean academy of maxillofacial plastic and reconstructive surgery, and related journals. The results were as follows: 1. The ratio of men to women was 4.50:1. 2. The age frequency was highest in the third decade(37.6%), and fourth(21.5%), second(15.5%), fifth(10.3%) decade in orders. 3. The most common location of facial bone fractures was the mandible(62.7%), and zygoma complex (22.6%), nasal bone(15.0%), and maxilla(13.0%) were next in order of frequency. 4. The major etiologic factors were traffic accident(37.9% ), fisticuffs(26.4%), and falldown and slip down(23.4%). 5. The frequent fracture site of mandible is symphysis(39.3%), angle(24,4% ), and condyle(22.5%). The ratio of left to right was 1.31:1. Open reduction(69.1%) was the more frequently using method of treatment in mandibular fracture than colsed reduction (28.6%). 6. The sites of zygoinatic fractures were zygoma complex(48.0%), zygornatic arch(35.7%), and combined(16.3%). The left to right ratio was 1.37:1. 7. The most frequent maxillary fracture was Le Fort I (31.4% ), and Le Fort II (27.1%), unilateral(14.3%), Le Fort III (7.6%) were next in order of frequency.

DETECT10N OF HUMAN PAPILLOMAVIRUS AND OVEREXPRESS1ON OF p53 IN SQUAMOUS CELL CARCINOMAS OF ORAL CAVITY

Epidemiological evidence suggests that human papillomavirus(HPV) infection is a high risk factor for the development of oral cancers. Many oncogenes, especially p53 suppressor gene, have a critical role of carcinogenesis in several human cancers including oral cancers. To investigate the prevalence of HPV infection and subtyping of high risk group(HPV-16, -18 and -33) HPV in oral cancers, the author studied 31 cases of squamous cell carcinomas arising from the oral cavity using polymerase chain reaction (PCR). The author also demonstrated the overexpression of p53 oncoprotein in the oral cancers using immunohistochemical methods. The correlation between HPVs infection and p53 overexpression in tumorigenesis of the oral cancers was evaluated. 1. Twenty-one cases(66.7%) among 31 cases of oral squamous cell carcinomas were positive for HPV-DNA. Among them, 16 cases were positive for HPV-16, 4 cases for HPV-18, and 2 cases for HPV-33. Two cases were coinfected with HPV-16 and HPV-18, and HPV-18 and HPV-33. 2. The prevalence of HPV infection appeared not correlated with tumor differentiation and clinical stages of oral squamous cell carcinomas. 3. The overexpression of p53 oncoprotein was present in 24 of 31 cases(77% ). In 21 HPV positive tumors 18 cases were positive for overexpression of p53 oncoprotein. Six cases were positive for p53 in ten HPV negative tumors. There was no correlation between HPV DNA detection rate and p53 overexpression. The above results suggest that HPV infection and p53 oncogene mutation play different roles in tumorigenesis of oral squamous cell carcinomas. No coexpression of p53 oncoprotein with HPV-DNA detection suggests that another etiologic mechanism other than HPV infection may be operative.

A STUDY ON THE CHANGE THE UPPER LIP AFTER SAGITTAL SPLIT RAMUS OSTEOTOMY

A study on the size of condyle and the posterior slope of the articular eminence in patients with temporomandibular joint disorders

0.05). 3. There were no statistically significant differences in the condylar ratio between the groups (p>0.05). 4. There were no statistically significant differences in the discrepancies of the left and right ramus length measurements between the groups (p>0.05). 5. The relative size of condyle to fossa in the group of temporomandibular disorders was smaller than that in the normal group (p<0.05).

Gingival overgrowth induced by immunosuppressant: case report

A Study Of Effect Of Pulsed Electromagnetic Fields On Osteogenesis In Rabbit Cranial Bone Defect

Pulsed electromagnetic field (PEMF) was used first to induce osteogenesis in 1974. The appliance which was consisted of the Helmholtz coil configuration have used to osteogensis. The objective of this study was to determine whether PEMF, a frequency of 100 Hz and magnetic field strength of 38 gauss applied to the calvarial defect in rabbit, could affect the induction of osteogenesis and the healing of the graft bone. This field should not produce excitation of nerve or muscle and heating the tissue. To evaluate the effect of PEMF on osteogenesis, 16 rabbit under the same condition was divided into 8 experimental groups and 8 control groups. 10 mm calvarial bone defects were formed around sagittal suture. The defect of left side was left without graft while the defect of right side was grafted by bone harvested from left side. A pulsed electromagnetic field was applied for 8 hours per day. Each group was sacrificed after 1 week, 2 weeks, 4 weeks, 8 weeks. Microscopic specimens were obtained from the calvarial bone defects and surrounding tissue using Hematoxylin-Eosin staining method. The results were as follows. 1. In the group which pulsed electromagnetic field was applied, new bone formation filled up the defect was observed after 4 and 8 weeks effectively. 2. There are no difference in the healing period for the fusion between the bone and graft bone. According to the result, the PEMF with 38 Gauss, 100 Hz was very effective in the healing of bone defect and new bone formation. So The PEMF will be useful in clinical aspect for oseteogenesis.

Genetic Alterations of Human Oral Cancers Using Comparative Genomic Hybridization

The development and progression of oral cancer is associated with an accumulation of multiple genetic alterations through the multistep processes. Comparative genomic hybridization(CGH), newly developed cytogenetic and molecular biologic technique, has been widely accepted as a useful method to allow the detection of genetic imbalance in solid tumors and the screening for chromosome sites frequently affected by gains or losses in DNA copy number. The authors examined 19 primary oral squamous cell carcinomas using CGH to identify altered chromosome regions that might contain novel oncogenes and tumor suppressor genes. Interrelationship between these genetic aberrations detected and major oncogenes and tumor suppressor genes previously recognized in carcinogenesis of oral cancers was studied. 1. Changes in DNA copy number were detected in 14 of 19 oral cancers (78.9%, mean: 5.58, range: 3~13). High level amplification was present in 4 cases at 9p23, 12p21.1~q13.1, 3q and 8q24~24.3. Fourteen cases(78.9%, mean: 3.00, range: 1~8) showed gains of DNA copy number and 12 cases(70.5%, mean: 2.58, range: 1~9) revealed losses of DNA copy number. 2. The most common gains were detected on 3q(52.6%), 5p(21.0%), 8q(21.0%), 9p(21.0%), and 11q(21.0%). The losses of DNA copy number were frequently occurred at 9p(36.8%), 17q(36.8%), 13q(26.3%), 4p(21.0%) and 9p(21.0%). 3. The minimal common regions of gains were repeatedly observed at 3q24~26.7, 3q27~29, 1q22~31, 5p12~13.3, 8q23~24, and 11q13.1-13.3. The minimal common regions of losses were detected at 9q11~21.3, 17p31, 13q22~34, and 14p16. 4. In comparison of CGH results with tumor stages, the lower stage group showed more frequent gain at 3q, 5q, 9p, and 14q, whereas gains at 1q(1q22~31) and 11q(11q13.1~13.3) were mainly detected in higher stage group. The loss at 13q22~34 was exclusively detected in higher stage. The results indicate that the most frequent genetic alterations in the development of oral cancers were gains at 3q24~26.3, 1q22~31, and 5p12~13.3 and losses at 9q11~21.3, 17p31, and 13q. It is suggested that genetic alterations manifested as gains at 3q24~26.3, 3q27~29, 5p12~13.3 and 5p are associated with the early progression of oral cancer. Gains at 1q22~31 and 11q13.1~13.3 and loss at 13q22-34 could be involved in the late progression of oral cancers.

MALIGNANT IVMPHOMA IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENT

A Clinical Study of Periapical Lesions