• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권2호
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• pp.185-190
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• 1991

비내분비성 골종양이나 연조직종양에서 유래되는 구루병이나 골연화증은 매우 드문질환으로 1947 년 이래로 14 명의 환자만이 보고되고 있다. 이 질환의 본태는 아직 밝혀지지 않았으나 종양에서 생성하는 인산염뇨유발성 물질이 신세뇨관에 영향을 주고 저인산염혈증을 일으키며 골조직의 석회화에 장애를 일으키는 것으로 생각된다. 본 증례의 환자는 약 4 년 전부터 지속된 심한 전신동통과 근육위축, 현저한 신장의 감소를 주소로 내원한 41 세 남자로 상악우측 치은부의 종양에 의한 전신적 골연화증의 진단하에 종양의 외과적적출을 시행하였으며 술후 환자의 혈청과 뇨의 생화학적결과는 12 일 후에 정상으로 회복되었고 임상증상은 수술후 6 주에 회복되었으며 4 달후에 촬영한 치과 방사선상 놀랄만한 골재생과 새로 형성된 치조백선의 형성이 관찰되었다. 적출된 종물은 거대세포육아종의 조직소견을 보였으며 종물의 적출에 의하여 골연화증의 치유소견이 관찰 되었기에 종양에 의한 골연화증의 회유한 증례로 사료되어 이에 보고하는 바이다.

• Journal of Periodontal and Implant Science
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• 제47권1호
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• pp.30-40
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• 2017

Purpose: Optical coherence tomography (OCT) is a noninvasive diagnostic technique that may be useful for both qualitative and quantitative analyses of the periodontium. Micro-computed tomography (micro-CT) is another noninvasive imaging technique capable of providing submicron spatial resolution. The purpose of this study was to present periodontal images obtained using ex vivo dental OCT and to compare OCT images with micro-CT images and histologic sections. Methods: Images of ex vivo canine periodontal structures were obtained using OCT. Biologic depth measurements made using OCT were compared to measurements made on histologic sections prepared from the same sites. Visual comparisons were made among OCT, micro-CT, and histologic sections to evaluate whether anatomical details were accurately revealed by OCT. Results: The periodontal tissue contour, gingival sulcus, and the presence of supragingival and subgingival calculus could be visualized using OCT. OCT was able to depict the surface topography of the dentogingival complex with higher resolution than micro-CT, but the imaging depth was typically limited to 1.2-1.5 mm. Biologic depth measurements made using OCT were a mean of 0.51 mm shallower than the histologic measurements. Conclusions: Dental OCT as used in this study was able to generate high-resolution, cross-sectional images of the superficial portions of periodontal structures. Improvements in imaging depth and the development of an intraoral sensor are likely to make OCT a useful technique for periodontal applications.

• Journal of Periodontal and Implant Science
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• 제40권4호
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• pp.194-200
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• 2010

Purpose: There is no consensus regarding the relationship between the width of keratinized mucosa and the health of periimplant tissues, but clinicians prefer to provide enough keratinized mucosa around dental implants for long-term implant maintenance. An apically positioned flap during second stage implant surgery is the chosen method of widening the keratinized zone in simple procedures. However, the routine suture techniques used with this method tend to apply tension over the provisional abutments and decrease pre-existing keratinized mucosa. To overcome this shortcoming, a pre-fabricated implant-retained stent was designed to apply vertical pressure on the labial flap and stabilize it in a bucco-apical direction to create a wide keratinized mucous zone. Methods: During second stage implant surgery, an apically displaced, partial thickness flap with a lingualized incision was retracted. A pre-fabricated stent was clipped over the abutments after connecting to the provisional abutment. Vertical pressure was applied to displace the labial flap. No suture was required and the stent was removed after 10 days. Results: A clinically relevant amount of keratinized mucosa was achieved around the dental implants. Buccally displaced keratinized mucosa was firmly attached to the underlying periosteum. A slight shrinkage of the keratinized zone was noted after the healing period in one patient, but no discomfort during oral hygiene was reported. Clinically healthy gingiva with enough keratinized mucosa was achieved in both patients. Conclusions: The proposed technique is a simple and time-effective technique for preserving and providing keratinized tissue around dental implants.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권6호
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• pp.520-530
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• 2006

Undifferentiated mesencymal stem cells(UMSCs) have been thought to be multipotent cells that can replicate as undifferentiated cells and that have the potential to differentiate into lineages of mesenchymal tissue including the bone, cartilage, fat, tendon, muscle, and marrow stroma. It can be used to sinus lifting, Guided bone regeneration, other bone graft in dental part. The purpose of this study is to evaluate the effect of mesencymal stem cells on sinus augmentation with autogenous bone, fibrin glue mixture in a rabbit model. 8 New Zealand white rabbits were divided randomly into 4 groups based on their time of sacrifice(1, 2, 4 and 8 weeks). First, undifferentiated mesenchymal stem cells were isolated from iliac crest marrow of rabbits and expanded in vitro. cell culture was performed in accordance with the technique described by Tsutsumi et al. In the present study, The animals were sacrificed at 1, 2, 4 and 8 weeks after transplantation, and the bone formation ability of each sides was evaluated clinically, radiologically, histologically and histomorphologically. According to the histological observations, Stem cell group showed integrated graft bone with host bone from sinus wall. At 2 and 4weeks, It showed active newly formed bone and neovascularization. At 8 weeks, lamella bone was observed in sinus graft material area. Radiologically, autobone with stem cell showed more radiopaque than autobone without stemcell. there were significant differences in bone volume between 2 and 4 weeks (p<0.05). In summary, the autobone with stem cells had well-formed, newly formed bone and neovasculization, compared with the autobone without stem cells (esp. 2 weeks and 4 weeks) The findings of this experimental study indicate that the use of a mixture of mesenchymal stem cell yielded good results in osteogenesis and bone volume comparable with that achieved by autogenous bone. Therefore, this application of this promising new sinus floor elevation method for implants with tissue engineering technology deserves further study.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권4호
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• pp.301-311
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• 2011

Introduction: This study examined the effect of the application of low intensity pulsed ultrasound on bone healing after an injection of adipose tissue-derived stem cells (ADSCs) during the implantation of a titanium implant in the tibia of diabetes-induced rats. Materials and Methods: Twelve Sprague-Dawely rats were used. After inducing diabetes, the ADSCs were injected into the hole for the implant. Customized screw type implants, 2.0 mm in diameter and 3.5 mm in length, were implanted in both the tibia of the diabetes-induced rats. After implantation, LIPUS was applied with parameters of 3 MHz, 40 mW/$cm^2$, and 10 minutes for 7 days to the left tibiae (experimental group) of the diabetesinduced rats. The right tibiae in each rat were used in the control group. At 1, 2 and 4 week rats were sacrificed, and the bone tissues of both tibia were harvested. The bone tissues of the three rats in each week were used for bone-to-implant contact (BIC) and bone area (BA) analyses and the bone tissues of one rat were used to make sagittal serial sections. Results: In histomorphometric analyses, the BIC in the experimental and control group were respectively, $39.00{\pm}18.17%$ and $42.87{\pm}9.27%$ at 1 week, $43.74{\pm}6.83%$ and $32.27{\pm}6.00%$ at 2 weeks, and $32.62{\pm}11.02%$ and $47.10{\pm}9.77%$ at 4 weeks. The BA in experimental and control group were respectively, $37.28{\pm}3.68%$ and $31.90{\pm}2.84%$ at 1 week, $20.62{\pm}2.47%$ and $15.64{\pm}2.69%$ at 2 weeks, and $11.37{\pm}4.54%$ and $17.69{\pm}8.77%$ at 4 weeks. In immunohistochemistry analyses, Osteoprotegerin expression was strong at 1 and 2 weeks in the experimental group than the control group. Receptor activator of nuclear factor kB ligand expression showed similar staining at each week in the experimental and control group. Conclusion: These results suggest that the application of low intensity pulsed ultrasound after an injection of adipose tissue-derived stem cells during the implantation of titanium implants in the tibia of diabetes-induced rats provided some positive effect on bone regeneration at the early stage after implantation. On the other hand, this method is unable to increase the level of osseointegration and bone regeneration of the implant in an uncontrolled diabetic patient.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권4호
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• pp.250-254
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• 2010

Introduction: This study evaluated the bone regenerative effect of silk fibroin mixed with platelet-rich fibrin (PRF) of a bone defect in rabbits. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The silk fibroin mixed with PRF was grafted into the right parietal bone (experimental group). The left side (control group) was grafted only PRF. The animals were sacrificed at 4 weeks and 8 weeks. A micro-computerized tomography (${\mu}$CT) of each specimen was taken. Subsequently, the specimens were decalcified and stained for histological analysis. Results: The average value of plane film analysis was higher in the experimental group than in the control group at 4 weeks and 8weeks after surgery. However, the difference was not statistically significant.(P>0.05) The tissue mineral density (TMD) in the experimental group at 4 weeks after surgery was significantly higher than the control group.(P<0.05) Conclusion: Silk fibroin can be used as a scaffold of PRF for rabbit calvarial defect repair.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권1호
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• pp.19-27
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• 2008

Thirty-six sinus grafts were performed in 34 patients with an alveolar crest bone height in the posterior maxilla of 3 to 5 mm before grafting. The sinuses were grafted using Bio-Oss alone or mixed with fibrin glue. Group 1 was the control group and included 25 patients who received a xenograft mixed in saline. Group 2 comprised 9 patients who received a xenograft and fibrin glue. The study was further subdivided at the time of 9 months. This histologic study evaluated by hematoxylin-eosin (H&E) and histomorphometric analysis whether fibrin glue in combination with Bio-Oss enhances bone regeneration in sinus floor elevation in humans. The new bone formation was better in Group 2 than in Group 1, but the difference was not significant. The absorption of the graft material was faster in Group 2 than in Group 1, in the short term, but better in Group 1 over the long term, although the difference was not significant. Lamellar bone was formed earlier in Group 1 compared to Group 2, but the difference was not significant. Overall, the surgery site stabilized earlier with new bone formation in Group 2 than in Group 1, but the difference was not significant. Combining a fibrin sealant and Bio-Oss could lead to improved scaffolds for bone tissue engineering based on the synergistic effects of the biomaterials. Therefore, Bio-Oss or Bio-Oss plus Tisseel may be used depending on the situation.

• Journal of Periodontal and Implant Science
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• 제28권4호
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• pp.611-632
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• 1998

Chitosan has been known as a wound healing agent. The purpose of this study was to evaluate the biocompatibility and guided bone regenerative effect of chitosan and chitosan-cellulose membranes. The effects of chitosan and chitosan-cellulose membranes on the growth and survival of human periodontal ligament cells were examined by rapid colorimetric MTT(tetrazolium) assay, and the tissue response and resorption pattern were observed by implanting the membranes into the subcutaneous tissue of the back of rats for 6 weeks. To evaluate the guided bone regenerative potential of membranes, the amount of newly formed bone in the rat calvarial defects(8mm in diameter) was measured by histomorphometry and radiomorphometry 1,2 and 4 weeks after implantation of membranes. Chitosan and chitosan-cellulose membranes showed no adverse effect on the growth and survival of human periodontal ligament cells. When membranes were subcutaneously implanted, inflammatory reaction was observed at 1 week and which gradually subsided 2weeks after implantation. Membranes remained intact throughout the experimental period of 6 weeks. Radiomorphometric analysis of the craniotomy sites revealed that chitosan and chitosan-cellulose membrane implanted sites showed increased radiopacity over control. Statistically significant differences with control were found in chitosan-cellulose membrane implanted group at 2 and 4 weeks, and chitosan membrane implanted group at 4 weeks(P<0.05). Histomorphometric data indicated a pattern of osseous healing similar to radiomorphometric analysis. There was a statistically significant difference between control and chitosan-cellulose membrane implanted group at 4 weeks(P<0.05). These results implicate that chitosan and chitosan-cellulose membrane might be useful for guided bone regeneration.

• Journal of Periodontal and Implant Science
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• 제42권1호
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• pp.13-19
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• 2012

Purpose: The aim of this study was to examine whether a previous peri-implantitis site can affect osseointegration, by comparing implant placement at a site where peri-implantitis was present and at a normal bone site. A second aim of this study was to identify the tissue and bone reaction after treating the contaminated implant surface to determine the optimal treatment for peri-implant diseases. Methods: A peri-implant mucositis model for dogs was prepared to determine the optimal treatment option for peri-implant mucositis or peri-implantitis. The implants were inserted partially to a length of 6 mm. The upper 4 mm part of the dental implants was exposed to the oral environment. Simple exposure for 2 weeks contaminated the implant surface. After 2 weeks, the implants were divided into three groups: untreated, swabbed with saline, and swabbed with $H_2O_2$. Three implants from each group were placed to the full length in the same spot. The other three implants were placed fully into newly prepared bone. After eight weeks of healing, the animals were sacrificed. Ground sections, representing the mid-buccal-lingual plane, were prepared for histological analysis. The analysis was evaluated clinically and histometrically. Results: The untreated implants and $H_2O_2$-swabbed implants showed gingival inflammation. Only the saline-swabbed implant group showed re-osseointegration and no gingival inflammation. There was no difference in regeneration height or bone-to-implant contact between in situ implant placement and implant placement in the new bone site. Conclusions: It can be concluded that cleaning with saline may be effective in implant decontamination. After implant surface decontamination, implant installation in a previous peri-implant diseased site may not interfere with osseointegration.

• Journal of Microbiology and Biotechnology
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• 제31권10호
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• pp.1401-1408
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• 2021

This study examined whether the oral administration of low-molecular-weight collagen peptide (LMCP) containing 3% Gly-Pro-Hyp with >15% tripeptide (Gly-X-Y) content could ameliorate osteoarthritis (OA) progression using a rabbit anterior cruciate ligament transection (ACLT) model of induced OA and chondrocytes isolated from a patient with OA. Oral LMCP administration (100 or 200 mg/kg/day) for 12 weeks ameliorated cartilage damage and reduced the loss of proteoglycan compared to the findings in the ACLT control group, resulting in dose-dependent (p < 0.05) improvements of the OARSI score in hematoxylin & eosin (H&E) and Safranin O staining. In micro-computed tomography analysis, LMCP also significantly (p < 0.05) suppressed the deterioration of the microstructure in tibial subchondral bone during OA progression. The elevation of IL-1β and IL-6 concentrations in synovial fluid following OA induction was dose-dependently (p < 0.05) reduced by LMCP treatment. Furthermore, immunohistochemistry illustrated that LMCP significantly (p < 0.05) upregulated type II collagen and downregulated matrix metalloproteinase-13 in cartilage tissue. Consistent with the in vivo results, LMCP significantly (p < 0.05) increased the mRNA expression of COL2A1 and ACAN in chondrocytes isolated from a patient with OA regardless of the conditions for IL-1β induction. These findings suggest that LMCP has potential as a therapeutic treatment for OA that stimulates cartilage regeneration.