• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.55-74
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• 1991

The purpose of this study was to investigate the influence of early functional load around osseointegrated titanium implants. 24 titanium plasma spray coated implants (ITI HS-type) were placed into the previously extracted site in the mandible of six adult dogs. The implants were divided into three groups : the control group was the implants without abutment during the experimental period; the experimental group I was loaded by connecting the contoured abutment after 6 weeks of healing; the experimental group II was loaded after 12 weeks of healing: and the mandibular second premolar and surrounding tissues were selected for natural tooth group to compare the implanted group. All dogs were injected intravenously tetracycline, alizarin red S, and calcein for bone labeling. After the experimental period of 18 weeks, the dogs were sacrificed and longitudinal sections of the bone-implant interface were cut and observed using light microscope, scanning electron microscope, and fluorescence microscope. The results of the study were as follows: 1. Light and scanning electron microscopically, all implant surfaces were well contact with bone tissue at the cortical layer, but some areas of cancellous bone were not contact directly. 2. Fluorescence microscopically, number and size of the new secondary osteons around the implant were increased than those of the natural tooth. 3. Fluorescence microscopically, linear and concentrical fluorescence was observed at or near the surface of all implants, and the bone formation and remodeling of the implants loaded after 6 week of healing were great, and unloaded implants were worst. 4. Fluorescence microscopically, endosteal bone formation was greater than periosteal bone formation at or near the implants. 5. Fluorescence microscopically, number and size of linear and concentric fluorescence was increased at the lingual side than the buccal side of the loaded implants. The result of the study indicate the possibility of the early load to the implant via a prosthesis.

• Journal of Acupuncture Research
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• v.24 no.5
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• pp.13-22
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• 2007

Objectives : The differentiation of osteoblasts is controlled by various growth factors and matrix protein expressed in bone. The aim of this study was to investigate the effects of many herbs medicine(KHBJs) for bone healing that induces osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic effects of KHBJs were evaluated by using cell proliferation(WST-8) assay, alkaline phosphatase(ALP) activity assay, colorimetric analysis of vascular endothelial growth factor(VEGF) expression in human osteoblast like SaOS-2 cell. Also, osteogenic activity of KHBJ fractions(KHBJB and KHBJR) by activity guided fractionation were evaluated. Results : About 7 KHBJs had effect on the proliferation of osteoblast like SaOS-2 cells, and dose-dependently increased alkaline phosphatase(ALP) activity. KHBJs markedly increased expression for VEGF. Fractionated KHBJs(KHBJB or KHBJR) not enhanced more than KHBJs on osteogenic activity in SaOS-2 cells. Conclusions: This study found that 7 KHBJs had effect on proliferation, ALP activity, and VEGF expression in osteoblast like SaOS-2 cells. These results propose that KHBJs can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.4
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• pp.499-507
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• 1994

The aim of this experiment is to compare the healing process of extraction sockets after immediate implant placement with those using autogenous bone grafts and guided tissue regeneration with Gore-Tex. The first lower premolars and the second premolars of six experimental dogs were extracted and Stryker fin type implants were placed into the extraction sockets immediately after extraction. In the control group, any graft materials were'not used and the dead space around implants was left in itself and covered with only periosteum. In the experimental group A, implants were covered with Gore tex without any bone grafts, and in the experimental group B, the dead space around implants was filled with the bone chips gained from drilling procedure. Each experimental dogs were sacrificed at the 1st, 2nd, 3rd, 6th, and 8th week and the specimens were observed by gross examination, radiological examination, and light microscopic examination. The following results were obtained. 1. Well healed soft tissue and no mobility of the implants were observed in control and two experimental groups. 2. In the radiogical examination, radiopacity around implants had been increased gradually. 3. In the microscopic examination, there were good healing process and active new bone formation in both in the experimental groups, Especially the more amount of new bone formation occurred in the experimental group B using bone chips. 4. Bone chip grafts and guided tissue regeneration (GTR) using Gore-Tex may be one of the successful methods in the immediate implantation.

• Archives of Craniofacial Surgery
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• v.20 no.6
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• pp.370-375
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• 2019

Background: Some parts of a maxillary fracture-for example, the medial and posterior walls-may remain unreduced because they are unapproachable or hard to deal with. This study aimed to investigate the self-healing process of unreduced maxillary membranous parts of fractures through a longitudinal computed tomography (CT) analysis of cases of unilateral facial bone injuries involving the maxillary sinus walls. Methods: Thirty-two patients who had undergone unilateral facial bone reduction surgery involving the maxillary sinus walls without reduction of the medial and posterior walls were analyzed in this retrospective chart review. Preoperative, immediate postoperative, and 3-month postoperative CT scans were analyzed. The maxillary sinus volume was calculated and improvements in bone continuity and alignment were evaluated. Results: The volume of the traumatized maxillary sinuses increased after surgery, and expanded significantly by 3 months postoperatively (p< 0.05). The significant preoperative volume difference between the normal and traumatized sides (p= 0.024) resolved after surgery (p> 0.05), and this resolution was maintained at 3 months postoperatively (p > 0.05). The unreduced parts of the maxillary bone showed improved alignment and continuity (in 75.0% and 90.6% of cases, respectively), and improvements in bone alignment and bone continuity were found to be correlated using the Pearson chi-square test (p= 0.002). Conclusion: Maxillary wall remodeling through self-healing occurred concomitantly with an increase in sinus volume and simultaneous improvements in bone alignment and continuity. Midfacial surgeons should be aware of the natural course of unreduced fractured medial and posterior maxillary walls in complex maxillary fractures.

• Journal of Korean Dental Science
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• v.5 no.1
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• pp.21-28
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• 2012

Purpose: In this study the bone healing ability of autogenous tooth bone graft material as a substitute material was evaluated in a mini-pig cranial defect model through histologic examinations and osteonectin reverse transcription polymerase chain reaction (RT-PCR) quantitative analysis. Materials and Methods: A defect was generated in the cranium of mini-pigs and those without a defect were used as controls. In the experimental group, teeth extracted from the mini-pig were manufactured into autogenous tooth bone graft material and grafted to the defect. The mini-pigs were sacrificed at 4, 8, and 12 weeks to histologically evaluate bone healing ability and observe the osteonectin gene expression pattern with RT-PCR. Result: At 4 weeks, the inside of the bur hole showed fibrosis and there was no sign of bone formation in the control group. On the other hand, bone formation surrounding the tooth powder granule was observed at 4 weeks in the experimental group where the bur hole was filled with tooth powder. Osteonectin gene expression; there was nearly no osteonectin expression in the control group while active osteonectin expression was observed from 4 to 12 weeks in the experimental group. Conclusion: We believe this material will show better results when applied in a clinical setting.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.1
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• pp.16-22
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• 2010

Objective: Bisphosphonate related osteonecrosis of the jaw (BRONJ) is reported in patients taken bisphosphonate for a long time, however, the mechanism of osteonecrosis in BRONJ was not clarified yet. This study was designed to investigate the effect of short administraion zoledronate on the healing pattern of periosteum and sinus membrane after iliac bone graft into maxillary sinus. Methods: In this study, 18 Newzeland rabbits were used. The animals were divided into 2 group. In the experimental group, rabbits were treated with weekly peritoneal injection (0.06 mg/kg/week) of zoledronate for three times. In the control group, rabbits were treated with saline solution injection instead of zoledronate. Periosteum and sinus membrane were harvested from one rabbit of the experimental group and one of the control group in the fourth week. The autogeneous bone was harvested from ilium and grafted into maxillary sinus. The rabbits were sacrificed at 1, 2, 4 and 8 weeks after bone graft. The healing pattern of periosteum and sinus membrane were evaluated histologically. Results: Inflammatory reaction in the periosteum was less conspicuous and healing process appeared earlier in experimental group compared with control group at 1, 2, 4 weeks. There were no differences of microscopic findings of sinus membrane between both groups at any weeks. Conclusion: Short-term use of zoledronate decreased the inflammatory reaction and enhanced healing process in the periosteum. These findings suggest the possibility that zoledronte suppress the function of macrophages.

• The Journal of the Korean dental association
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• v.16 no.1 s.104
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• pp.43-50
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• 1978

The purpose of this study is to determine the effects of Cyclophosphamide on the healing process of fractures of the mice. Tweny-one young adult male mice were used. All of them were experimentally fractured in the left mandibular body areas, and Cyclophosphamide 0.1mg. per 30gr. body wt. was administrated intramuscularly to the experimental group. the mice of both control and experimental groups were sacrificed 1,3,5,7,10,14, and 21st day after operations and microscopic slides were made. The author has observed the histopathological findings. The results were as follows; 1. There were no specific difference between the experimental and control group in the early stage (1~5th day after operation) of the healing process of the mandibular fracture. 2. In the healing process of fractures 7-10th day after operation, the fibrous tissure formation and osteoblastic activity were poor in the experimental groop compared with the control group. 3. In the healing process of fractures 14-21th day after operation, the connective tissue and new bone formation were very poor in the experimental group compared with the control group. 4. On the whole, cyclophosphamide affected the experimentally fractured wound to delay healing in the jaw bone of the mice.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.123-140
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• 1997

The purpose of this study was to investigate effects of osteoporosis on fracture wound healing in the calcium deficient rat. To research the experiment some ten-week old Wistar strain rats with approximately 300 gms weight were selected. Then, the rats were divided into two groups: Normal diet group(rats given a normal diet before and after bone fracture) and Low calcium diet group(rats given a low calcium diet before and after bone fracture). Both groups had been provided with each diet for three weeks. When the rats became thirteen weeks old, the mandibular angle of rats in both groups was artificially fractured for test. The healing of fracture wounds was reviewed by using soft x-ray radiography and /sup 99m/Tc-MDP bone scan and also histopathologic examination. The obtained results were as follows : 1. The radiolucency of the fracture site for the Normal diet group started to decrease from the 14th day since the experiment was made, while the Low calcium diet group began decrease in the radiolucency from the 21st day of the experiment. The radiolucency for the Normal diet group disappeared at the 42nd day, but one for the Low calcium diet group disappeared at the 56th day of the experiment. 2. The highest uptake rate of /sup 99m/Tc-MDP stood at the 14th day of the experiment in the Normal diet group and the Low calcium diet group's maximum rate was recorded at the 21st day of the experiment. These both groups were gradually experiencing decrease in the uptake rate as the experiment time was going on. However, the uptake rate in the Low calcium diet group was lower than one in the Normal diet group. 3. For the Normal diet group, the newly formed trabeculae, which were similar to one of the surroundung bone, were seen at the 42nd day of the experiment. On the other hand, the Low calcium diet group showed at the 56th day of the experiment that the osteoporotic findings looked weak, irregular trabeculae, and also large bone marrow space were observed clearly. As a result of the above experiment, it is said that the healing of the fracture can be completed for both groups, the Normal diet group and the Low calcium diet group. However, the amount of the newly formed bone wound in the Low calcium diet group is rather decreased compared to one in the Normal diet group and at the same time the healing of the fracture is delayed in the Low calcium diet group. Consequently, for the successful healing of fracture in osteoporosis, it is considered that the management of the etiologic factors of osteoporosis must be preceded. The more study of calcium metabolism and functions of osteoblast and osteoclast needs to proceed on.

• Journal of Periodontal and Implant Science
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• v.39 no.sup2
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• pp.287-291
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• 2009

Purpose: The objective of this clinical presentation was to present a clinical case series report of socket preservation, sinus augmentation, and bone grafting using a horse-derived biomaterial. Methods: A horse-derived biomaterial was used in 8 patients for different indications including socket preservation following tooth extraction, osseous bone grafting, and sinus augementation procedures. Surgeries were performed by a well trained specialist and clinical radiographs were obtained at designated intervals. Biopsy cores of 2 ${\times}$ 8 mm prior to implant placement was obtained following a healing interval of 4 - 6 months. A clinical and histologic evaluation was performed to evaluate the clinical effectiveness and biocompatibility of the biomaterial. Results: All surgeries in 8 patients were successful with uneventful healing except for one case with membrane exposure that eventually resulted with a positive outcome. Radiographic display of the healing phase during different intervals showed increased radiopacity of granular nature as the healing time increased. No signs of adverse effect or infection was observed clinically and the tissues surrounding the biomaterial seemed well-tolerated with good intentional healing. The augmented sinuses healed uneventfully suggesting in part, good biocompatibility of the biomaterial. Dental implants placed following socket preservation were inserted with high initial torque suggesting good initial stability and bone quality. Conclusions: Our results show that at least on a tentative level, a horse-derived biomaterial may be used clinically in socket preservation, sinus augmentation, bone grafting techniques with good intentional healing and positive results.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.3
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• pp.240-248
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• 1999

To investigate the expression pattern of noncollagenous bone matrix proteins such as osteonectin(OSN), osteopontin(OPN) and osteocalcin(OSC) mRNA during bony healing procedure induced by guided bone regeneration method, we made artificial defects on bilateral femur of rats. Then induced bony healing by application of a nonabsorbable PTFE membrane in experimental sites and without its application in control sites for 3 weeks. The mRNA expression pattern at specimens obtained at 1, 2 and 3 weeks after operation was detected by in situ hybridization method using its antisense mRNA probes. The experimental sites revealed more rapid and favorable bony healing than control sites and new bone formation was limited within defected area by inhibitory activity of bone marrow cells. In experimental sites, the OSN and OSC mRNA were expressed strongly on osteoblasts of regenerating cortical bone at 1st week and on osteoblasts lining the trabecular bone in marrow space at 3rd week, whereas, in control sites, their expression were noted on osteoblasts lining the reactively formed sponge bones at 2nd and 3rd week. In addition, the OPN mRNA was expressed on osteoblasts and osteoclasts at sites of remodeling and osteocytes of remained trabecular bone of defected area in experimental sites and on macrophages at 1st week and osteoclasts at sites of remolding at 2nd and 3rd week in control sites. The above findings suggest that the more rapid and favorable bony healing might be induced by blocking of invading fibrous connective tissue into bony defects. And the earlier expression of OSN and OSC mRNA on osteoblasts of experimental sites suggest that the formation and resorption of regenerating bone was more rapidly progressed in confined spaces made by applicate membranes.