• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.2
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• pp.220-229
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• 2008

Purpose: The present study was aimed to examine the effect of acellular dermal matrix ($AlloDerm^{(R)}$) grafted to the experimental tissue defect on tissue regeneration. Materials and Methods: Male albino rabbits were used. Soft tissue defects were prepared in the external abdominal oblique muscle. The animals were then divided into 3 groups by the graft material used: no graft, autogenous dermis graft, and $AlloDerm^{(R)}$ graft. The healing sites were histologically examined at weeks 4 and 8 after the graft. In another series, critical sized defects with 8-mm diameter were prepared in the right and left iliac bones. The animals were then divided into 5 groups: no graft, grafted with autogenous iliac bone, $AlloDerm^{(R)}$ graft, $AlloDerm^{(R)}$ graft impregnated with rhBMP-2, and $AlloDerm^{(R)}$ graft with rhTGF-${\beta}1$. The healing sites of bone defect were investigated with radiologic densitometry and histological evaluation at weeks 4 and 8 after the graft. Results: In the soft tissue defect, normal healing was seen in the group of no graft. Inflammatory cells and foreign body reactions were observed in the group of autogenous dermis graft, and the migration of fibroblasts and the formation of vessels into the collagen fibers were observed in the group of $AlloDerm^{(R)}$ graft. In the bone defect, the site of bone defect was healed by fibrous tissues in the group of no graft. The marked radiopacity and good regeneration were seen in the group of autogenous bone graft. There remained the traces of $AlloDerm^{(R)}$ with no satisfactory results in the group of $AlloDerm^{(R)}$ graft. In the groups of the $AlloDerm^{(R)}$ graft with rhBMP-2 or rhTGF-${\beta}1$, there were numerous osteoblasts in the boundary of the adjacent bone which was closely approximated to the $AlloDerm^{(R)}$ with regeneration features. However, the fibrous capsule also remained as in the group of $AlloDerm^{(R)}$ graft, which separated the $AlloDerm^{(R)}$ and the adjacent bone. Conclusions: These results suggest that $AlloDerm^{(R)}$ can be useful to substitute the autogenous dermis in the soft tissue defect. However, it may not be useful as a bone graft material or a carrier, since the bone defect was not completely healed by the bony tissue, regardless of the presence of osteogenic factors like rhBMP-2 or rhTGF-${\beta}1$.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.501-521
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• 2002

The purpose of this study is to evaluate the influences of the bone morphogenetic protein (BMP) on the healing of periodontal ligament and alveolar bone after replantation of tooth, and to examine the possibility of its clinical application. 45 Sprague Dawley rats weighted about 100 gram were divided into 3 experimental groups by different dose of BMP. All the upper right and left 1st molar were extracted after 5 days feeding of 0.4% ${\beta}$-aminopropionitrile, and right molar were used as experimental group and left molar were used as control group. The root surface of experimental molar were treated with 25,50 and l00ng/ml of human recombinant Bone morphogenetic protein-4 (rh-BMP-4) with micropipet, and 1M Sodium hypochloride were used on control root surface. All the experimental animals were sacrificed as 1, 2, 4, 7 and 14 days after autoreplantation of upper 1st molar into their own position. The maxilla were disected included both side of 1st molar. The collected tissue were processed from demineralization to paraffin embeding as usual procedure, and the specimens were prepared with Hematoxylin-Eosin stain for the light microscopic evaluation. The results of this study were as follows : 1. There was no significant differences between control and experimental site on 1 and 2 days after replantation of tooth. In the case of 4th days, the evidence of tissue regeneration were observed on experimental site to compare the controls. New osteoid were revealed on high concentration of BMP at 7 days after replantation, and it became more obvious at 14 days, 2. The effect of the rh-BMP-4 coated on root surface was revealed slight influences for the prolifertion of cells of periodontium and tissue regeneration as dose-dependent pattern. 3. Bony ankylosis was observed between alveolar bone and root surface due to the remarkable amount of osteoid formation on the 14 days after replantation of root. In the conclusion, it was suggested that topical application of the rhBMP-4 on the root surface has influence on the periodontal ligament and alveolar bone. The application method of BMP on the root should be designed with calculation of proper concentration.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.85-97
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• 1998

The purpose of this study was to observe the effects of sodium fluoride on the bony repair and regeneration processes after the rapid palatal expansion in the growing dogs. Eighteen dogs were divided into experimental and control groups. They were in the late mixed dentition. The rapid Palatal expansion was undertaken in all the animals($180^{\circ}$ turn/day) for ten days. The animals were sacrificed on 0, 15 and 45 days after the finish of expansion. One mg NaF/kg of body weight/day were given orally to the experimental group. Blood samples were drawn before and after expansion and the se겨m calcium, phosphate and alkaline phosphatase level were measured. The undecalcified bone section of midpalatal suture area was made, and observed under the light microscopy The results were as follows ; 1. The day after expansion, the infiltration of inflammatory cells were prominent and the new bone formation started at the edges of the two palatal plates bodering the midpalatal suture in both groups. Especially, the newly formed osteoid were very extensive and the osteoblasts lining the osteoid were very active in the experimental group. 2. At fifteen days after expansion, the active osteoblasts lining the osteold at the surface of trabecular bony spicules and active new bone formation were observed in the both groups. However, the cellular activity and new bone formation were more prominent In the experimental group. 3. At forty five days after expansion, the continuous osteoid and new bone formation and active osteoblasts were observed in the experimental group. But these phenomena were not observed in the control group. In the control group, the numerous osteoclasts were adjacent midpalatal suture and the bony remodeling process was begun. The serum alkaline phosphatase level was maintained highly in the experimental group, but decreased in the control. According to the above results, the author reached the conclusion that sodium fluoride has the stimulation effects on the osteoid production of the osteoblasts during the healing process after the rapid Palatal expansion more continuously.

• The Journal of the Korean bone and joint tumor society
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• v.9 no.2
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• pp.139-147
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• 2003

Purpose: The purpose of this study was to determine if bony union can be obtained when a bone graft substitute is transplanted in order to treat a benign bone tumor and if there is a difference between calcium sulfate and hydroxyapatite in the healing procedure when the degree of the bony union after the bone graft are compared. Materials and Methods: This study selected 20 cases, in which a curettage on the benign bone tumors was conducted and a bone graft substitute was transplanted. The area of the focus, the new bone formation, the recurrence of the focus in the plain radiographs and histological findings were observed. Results: Twenty cases (13 males, 7 females) were evaluated. Their mean age at surgery was 15.8 years (2~45), and the mean follow-up period was 3 years. The mean area of focus was 30.7 $cm^3$ in the radiographs, and 19 cases showed successful results in the ultimate visit, while 1 case has a recurrence of the focus. Conclusion: Calcium sulfate has osteoconduction and superior bioavailability, and is absorbed in vivo in proportion to the new bone formation. On the other hand, hydroxyapatite has good osteoconduction. It can result in better bone formation when it is combined with an autologous bone graft, autologous bone marrow, and an allogenic bone graft, but is absorbed in vivo more slowly than the former.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.1
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• pp.36-48
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• 2008

To repair bone defects in the oral and maxillofacial field, bone grafts including autografts, allografts, and artificial bone are used in clinical dentistry despite several disadvantages. The purpose of this study was to evaluate new bone formation and healing in rat calvarial bone defects using hydroxyapatite (HA, $Ca_{10}[PO_4]_6[OH]_2,\;Bongros^{(R)}$, Bio@ Co., KOREA) and tricalcium phosphate (${\beta}-TCP,\;Ca_3[PO_4]_2$, Sigma-Aldrich Co., USA) mixed at various ratios. Additionally, this study evaluated the effects of type I collagen (Rat tail, BD Biosciences Co., Sweden) as a basement membrane organic matrix. A total of twenty, 8-week-old, male Sprague-Dawley rats, weighing 250-300g, were divided equally into a control group (n=2) and nine experimental groups (n=2, each). Bilateral, standardized transosseous circular calvarial defects, 5.0 mm in diameter, were created. In each experimental group, the defect was filled with HA and TCP at a ratio of 100:0, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, and 0:100 with or without type I collagen. Rats were sacrificed 4 and 8 weeks post-operation for radiographic (standardized plain film, Kodak Co., USA), histomorphologic (H&E [Hematoxylin and Eosin], MT [Masson Trichrome]), immunohistochemical staining (for BMP-2, -4, VEGF, and vWF), and elementary analysis (Atomic absorption spectrophotometer, Perkin Elmer AAnalyst $100^{(R)}$). As the HA proportion increased, denser radiopacity was seen in most groups at 4 and 8 weeks. In general radiopacity in type I collagen groups was greater than the non-collagen groups, especially in the 100% HA group at 8 weeks. No new bone formation was seen in calvarial defects in any group at 4 weeks. Bridging bone formation from the defect margin was marked at 8 weeks in most type I collagen groups. Although immunohistochemical findings with BMP-2, -4, and VEGF were not significantly different, marked vWF immunoreactivity was present. vWF staining was especially strong in endothelial cells in newly formed bone margins in the 100:0, 80:20, and 70:30 ratio type I collagen groups at 8 weeks. The calcium compositions from the elementary analysis were not statistically significant. Many types of artificial bone have been used as bone graft materials, but most of them can only be applied as an inorganic material. This study confirmed improved bony regeneration by adding organic type I collagen to inorganic HA and TCP mixtures. Therefore, these new artificial bone graft materials, which are under strict storage and distribution systems, will be suggested to be available to clinical dentistry demands.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.3
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• pp.325-341
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• 2003

Statement of problem: In cases where bony defects were present, guided bone regenerations have been performed to aid the placement of implants. Nowadays, the accepted concept is to isolate bone from soft tissue by using barrier membranes to allow room for generation of new bone. Nonresorbable membranes have been used extensively since the 1980's. However, this material has exhibited major shortcomings. To overcome these faults, efforts were made to develop resorbable membranes. Guided bone regenerations utilizing resorbable membranes were tried by a number of clinicians. $Bio-Gide^{(R)}$ is such a bioresorbable collagen that is easy to use and has shown fine clinical results. Purpose: The aim of this study was to evaluate the histological results of guided bone regenerations performed using resorbable collagen membrane($Bio-Gide^{(R)}$) with autogenous bone, bovine drived xenograft and combination of the two. Surface morphology and chemical composition was analyzed to understand the physical and chemical characteristics of bioresorbable collagen membrane and their effects on guided bone regeneration. Material and methods: Bioresorbable collagen membrane ($Bio-Gide^{(R)}$), Xenograft Bone(Bio-Oss), Two healthy, adult mongrel dogs were used. Results : 1. Bioresorbable collagen membrane is pure collagen containing large amounts of Glysine, Alanine, Proline and Hydroxyproline. 2. Bioresorbable collagen membrane is a membrane with collagen fibers arranged more loosely and porously compared to the inner surface of canine mucosa: This allows for easier attachment by bone-forming cells. Blood can seep into these spaces between fibers and form clots that help stabilize the membrane. The result is improved healing. 3. Bioresorbable collagen membrane has a bilayered structure: The side to come in contact with soft tissue is smooth and compact. This prevents soft tissue penetration into bony defects. As the side in contact with bone is rough and porous, it serves as a stabilizing structure for bone regeneration by allowing attachment of bone-forming cells. 4. Regardless of whether a membrane had been used or not, the group with autogenous bone and $Bio-Oss^{(R)}$ filling showed the greatest amount of bone fill inside a hole, followed by the group with autogenous bone filling, the group with blood and the group with $Bio-Oss^{(R)}$ Filling in order. 5. When a membrane was inserted, regardless of the type of bone substitute used, a lesser amount of resorption occurred compared to when a membrane was not inserted. 6. The border between bone substitute and surrounding bone was the most indistinct with the group with autogenous bone filling, followed by the group with autogenous bone and $Bio-Oss^{(R)}$ filling, the group with blood, and the group with $Bio-Oss^{(R)}$ filling. 7. Three months after surgery, $Bio-Gide^{(R)}$ and $Bio-Oss^{(R)}$ were distinguishable. Conclusion: The best results were obtained with the group with autogenous bone and $Bio-Oss^{(R)}$ filling used in conjunction with a membrane.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.141-148
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• 2010

The bilateral sagittal split ramus osteotomy (BSSRO) is preferred method of surgical correction for mandibular prognathism, retrognathism and asymmetry. This technique performed from primarily an intraoral incision to avoid a scar. After forward movement of the distal segment of the mandible, healing of bone by primary or secondary intention is easily accomplished through large areas of cancellous bony overlap. When rigid fixation is used for the BSSRO, it is possible to open the mouth during the immediate post-operative period because it promotes the healing process. Although this surgical procedure has been well-documented, the incidence of postoperative trigeminal neurosensory disorder in the region of the inferior alveolar nerve and the mental nerve remains one of the major complication. However, evaluation of objective methods for sensory recovery patterns is insufficient although most patients find their sensory return. Neurometer electrodiagnostic device performs automated neuroselective sensory nerve conduction threshold evaluation by determining current perception threshold (CPT) measures. The purpose of this study was to evaluate the sensory recovery patterns of inferior alveolar and mental nerve over time. Nerve examination with a neurometer was performed in 30 patients undergoing the BSSRO at pre-operative, post-operative 1-, 2-, 4- week, and 2-, 3-, 4-, 5-, 6- month follow-up visits after the osteotomy to compare the differences of nerve injury and recovery patterns after the BSSRO with or without genioplasty and sensory recovery patterns associated with the kind of nerve fiber.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.1
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• pp.117-129
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• 1989

The commercial availability of processed heterogenous bone has provided the surgeons with almost unlimited supply, avoidance of additional operation and prevention of the postoperative complications. In addition to these merits, unnecessary bone bank, easy availibility and storage have been achieved. The purpose of this study was to compare and examine the healing capacity of Kiel bone, Pyrost and Osteovit which used as the processed heterografts for the reconstruction of bony defect. Twenty rabbits weighing about 1.7-2.0 Kg were selected and divided into two groups. In experimental group A, the left mandibular defect was allowed to fill with blood, and the right defect was filled with Kiel bone. In experimental group B, the left defect was grafted with Pyrost, and the right with Osteovit. The experimental animals were sacrified after 1, 2, 4 and 8 weeks and the grafted site was studied histologically. To evaluate the strength of healed bone, 2 rabbits from each experimental group and a nonoperated control were sacrified at the 6th week after implantation and used for biometric testing on universal testing machine. The results obtained were as follows : 1. It was considered that these heterogenous bone grafts has feeble or absent immunogenicity since all of them appeared to evoke little inflammatory or forign body reaction. 2. In all experimental groups, new bone formation began from the adjacent region of host bone and extended progressively into the defect sites. New bone was partly formed within the intertrabecular space of the implant and gradually united with the bone that formed at the margin of the host bone. 3. With Pyrost bone formation was rapid and prominent comparing with other graft materials. 4. Osteovit was begun to be absorbed from 2 weeks, and Kiel bone from 4 weeks, however Pyrost was remained to be intact until the end of 8 weeks. 5. As the results of tensile test, the mean values of maximum tensile stress were 1.11${\uparrow}$ $Kgf/mm^{2}$ in Pyrost implanted specimens, 0.85 $Kgf/mm^{2}$ in Osteovit, 0.42 $Kgf/mm^{2}$ in Kiel bone, 0.66 $Kgf/mm^{2}$ in blood filled specimens and 1..13 $Kgf/mm^{2}$ in control. These results indicate that heterogenous bones grafted have little antigenicity to the host tissue, and that they mediate effectively osteoconduction by providing the scaffold for the bone formation. Pyrost and Osteovit appeared to be suitable for the clinical use.

• Journal of Periodontal and Implant Science
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• v.32 no.2
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• pp.403-414
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• 2002

I. Purpose of Study Zea Mays L. has been known to be effective for improving periodontal health and Magnoliae cortex to have effective antibacterial and antimicrobial activity against periodontal pathogens. The purpose of this study was to examine the biologic effects of Zea Mays L. and Magnoliae cortex extract mixtures on healing of rat calvarial bone defects. II. Materials & Methods 8mm circular defects were prepared on rat calvaria during surgical procedures of 180 Sprague-Dawley rats. The ethanolic extracts of Magnoliae cortex and Zea Mays L. and these two natural extract 1:1 and 2:1 (Magnoliae: Zea Mays L.) ratio mixtures were oral administrated by oral zondes once a day at two different dose of 94.5mg/kg, 189mg/kg body weight. There are nine groups of rats in this study: control group (no sample loading), Magnoliae cortex extract loading groups (I,II)(94.5mg/kg,189mg/kg respectively), Zea Mays L. extract loading groups (I,II), M:Z(1:1) loading groups (I,II), M:Z(2:1) loading groups(I,II). Rats were sacrificed at 4 weeks and 6 weeks after surgery. New bone formations around calvarial defects were radiographically and histologically measured by computerassisted histomorphometry. Each data was statistically analyzed by One-way ANOVA test. III. Results There were statistical significances between negative control group and the other test groups on radiographical and histological quantitative assessments. Among test groups, mixture groups showed statistical significances, especially, M:Z (2:1) groups (I and II) were highly significant.(p<0.05) These results implicated that the mixture of Magnoliae and Zea Mays L. (2:1 mixing ratio) with 94.5mg/kg concentration might be highly effective on the wound healing of bony defected site and have potential possibilities as a useful drug to promote bone tissue regeneration.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.2
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• pp.118-126
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• 2006

In oral and maxillofacial surgery, bone graft is very important procedure for functional and esthetic reconstruction. So, many researcher studied about bone graft material like autogenous bone, allograft bone and artificial bone materials. The purpose of this study is to evaluate the quantity of bone generation induced by $Grafton^{(R)}$ graft, human allogenic demineralized bone matrix. Total 24 sites of artificial bony defects prepared using trephin bur(diameter 8 mm) on parietal bone of six adult New Zealand White rabbits. Experimental group had six defect sites which grafted $Grafton^{(R)}$(0.1 cc). Active control group had nine defect sites, into which fresh autogenous bone harvested from own parietal bone was grafted and passive control group had nine defect sites without bone graft. After six weeks postoperatively, the rabbits were sacrificed. The defects and surrounding tissue were harvested and decalcified in 10% EDTA, 10% foamic-acid. Specimens were stained with H&E. New bone area percentage in whole defect area was measured by IMT(VT) image analysis program. Quantity of bone by $Grafton^{(R)}$ graft was smaller than that of autograft and larger than that of empty defects. In histologic view $Grafton^{(R)}$ graft site and autograft site showed similar healing progress but it was observed that newly formed bone in active control group was more mature. In empty defect, quantity and thickness of new bone formation was smaller than in $Grafton^{(R)}$-grafted defect. $Grafton^{(R)}$ is supposed to be a useful bone graft material instead of autogenous bone if proper maintenance for graft material stability and enough healing time were obtained.