• Journal of Periodontal and Implant Science
• /
• v.39 no.2
• /
• pp.167-176
• /
• 2009

Purpose: The purpose of this study is to histologically and histomorphometrically evaluate the effect of PLGA on bone regeneration compared with bone graft material. Methods: The experimental study was conducted in 10 rabbits with 2 different healing periods of 2 and 4 weeks. Following surgical exposure of the calvarium, 4 circular bone defects with a diameter of 4.6mm were formed. Rabbits were divided into control group, test groups I, and II. 10 defects assigned to the test group Ⅰ were grafted with Nu-oss and other 10 defects assigned to the test group II were grafted with PLGA. The rest of the defects were in the negative control group. At 2nd and 4th week after surgery, 10 rabbits were sacrificed through intracardiac perfusion and then specimens were obtained. Histological analysis was performed following staining with trichorme and transversal sectioning of the calvarial bone. Results: A group which used PLGA showed tissue reactions characterized by severe inflammation, rather than distinctive new bone formation. Conclusions: The present experimental investigations have failed to prove any beneficial effects of PLGA. PLGA used in this study exhibited foreign body reactions and a less favorable pattern of new bone formation in comparison to control group. Conclusion: PLGA did not function as scaffold. Further investigations of many types of micro PLGA that could improve its potential in GBR procedures are needed.

• Journal of Veterinary Clinics
• /
• v.27 no.4
• /
• pp.450-452
• /
• 2010

A 4-year-old male Yorkshire terrier was referred to us with signs of vomiting and unconsciousness due to a blunt head trauma. Gross examinations detected facial edema, subcutaneous hemorrhage and hypersalivation. A survey radiograph located an occipital fragment which was displaced caudally. A three-dimensional computed tomographic reconstruction demonstrated that the ventral portion of the fragment was attached incompletely. Because of the instability of the fragment, it was decided to perform an esquillectomy. After removing the fragment, the defect was reinforced with a muscular flap originating from the splenius muscle. The patient's condition gradually improved except for a slightly ataxic gait. At 20 months follow-up, there was no evidence of ataxia. The neurological status did not deteriorate before starting surgical intervention, although the patient sustained a skull fracture with severe intracranial hemorrhage. It is likely that the fragment being displaced outwardly played an important role in preventing an increase in intracranial pressure which could have led to neurological deterioration.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.21 no.1
• /
• pp.1-12
• /
• 1999

The purpose of this study was to evaluate the healing process of the calvarial defect filled with hydroxylapatite(HA) and $TGF-{\beta}$ in Rat. 72 Sprague-Dawly rats were divided into 3 groups, control and two experimental groups. Bony defect were artificially prepared in the calvaria of all 72 rats and followed by implantation of HA (experimental group of 24 rats) and HA+$TGF-{\beta}$(another experimental group of 24 rats) into the defects. Sequential sacrifice was performed at 1, 2, 4, 6, 8, 12 weeks of experiment. Obtained specimen was stained with Hematoxylin and Eosin, Masson's Trichrome and Immunohistochemistry. The results were as follows, 1. Granulation tissue was prominent on control group in 1 and 2 weeks. Bony defects were filled with dense fibrous tissue through the whole experimental period and osteoinduction could not be observed in all groups. 2. Inflammatory cell infiltration was prominent on control group in 1 and 2 weeks and osteoclastic activity was high in HA implanted experimental group at 1 and 2 weeks. 3. Inflammatory cell infiltration was less and maturation of fibrous tissue could be found on HA+$TGF-{\beta}$ implanted experimental group at 1 and 2 weeks. 4. Osteoconduction activity was high in HA+$TGF-{\beta}$ implanted experimental group at 2 and 4 weeks but there was no difference after 6 weeks among 3 groups. 5. In grafted site of HA+$TGF-{\beta}$ implanted group, osteonectin expression was slightly increased from 1 week to 6 weeks. In the host site, it was increased from 1 to 4weeks. 6. In grafted site of HA+$TGF-{\beta}$ implanted group, osteocalcin expression was high at 4 weeks. In the host site, we could find the difference among 3 groups. From above results, the HA with mixture of $TGF-{\beta}$ has the potentiality of promoting bone formation in the bony defect area in the rat.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.33 no.5
• /
• pp.464-469
• /
• 2007

The bone graft materials are grossly divided into autogenous bone, allogenic bone, xenogenic bone, and alloplastic material. Among the various allogenic graft materials, hydroxyapatite($Ca_{10}(PO_4)_6(OH)_2$, HA), the main inorganic phase of human hard tissue, is widely used as a repair material for bones. When HA applied to bony defect, however, it may be encapsulated with fibrous tissue and floated in the implanted area by the lack of consolidation. Fluoridated hydroxyapatite($Ca_{10}(PO_4)_6(OH)_2$, FHA), where F- partially replaces the OH- in the hydroxyapatite, is considered as an alternative material for bone repair due to its solubility and biocompatibility. This study was designed to find out the bone healing capacity of FHA newly produced as a nanoscale fiber in the laboratory. We implanted HA and FHA in the rabbit cranium defect and histologically analysed the specimen. The results were as follows. 1. In the 4 weeks, fibrous connective tissue and little bone formation around materials of the experimental group I implanted HA were observed. In the experimental group II implanted FHA, newly formed bone around materials were observed. 2. In the 8 weeks, the amount of newly formed and matured bone of the experimental group II was more than the experimental group I and control group. From the results obtained, we suggest that FHA, newly synthesized, is relatively favorable bone substitute with bioconpatibility and has better bone healing capacity than pure HA.

• Journal of Periodontal and Implant Science
• /
• v.30 no.1
• /
• pp.91-104
• /
• 2000

Many synthetic bone materials have been studied for their potential of regenerative effects in periodontal tissue. Safflower seeds have been traditionally used as a drug for the treatment of fracture and blood stasis in oriental medicines. The purpose of this study was to assess and compare the osseous responses in rat calvarial defects between bone substitutes such as calcium carbonate and bovine-derived hydroxyapatite and feeding of safflower seeds. The calvarial defects were made with 8 mm trephine bur in 24 Sprague-Dawley rats. Two graft materials were implanted in each experimental groups, whereas the control and safflower seed feeding groups were sutured without any other treatment. And then the rats of safflower seed feeding group were supplied with 3 g/day of safflower seeds. Each group was sacrificed at 4 weeks and 8 weeks. To study a histopathology related to bone healing and regeneration, Goldner's Masson Trichrome stain was done at each weeks. The tissue response was evaluated under light microscope. There were more osteoblastic activity, new bone formation, dense bony connective tissues in bovine-derived hydroxyapatite group compared to other groups at 8 weeks. The osseous defect area of safflower seed feeding group was filled with prominent fibrous tissues, where less inflammatory infiltration and new capillary proliferation. In the early phase of bone healing, safflower seed feeding reduces the inflammatory response and promotes the proliferation of connective tissue. These results suggest that natural bovine-derived HA and safflower seed feeding could enhance the regenerative potential in periodontal defects.

• Journal of Periodontal and Implant Science
• /
• v.31 no.2
• /
• pp.389-400
• /
• 2001

Previous studies have demonstrated an increase in bone mass and density with the use of bisphosphonate in osteoporosis. This agent acts as an inhibitor of osteoclastic activity, and results in increase of net osteoblastic activity. Currently, it has been reported that bisphosphonate has direct effect on osteoblast. This study was designed to evaluate the effect of alendronate on bone regeneration in defect of rat calvaria. The animals used for these experiments were 48 male rats, over 6-8 weeks old. They were divided into three groups according to the dose of alendronate($MK-217^{(R)}$, Merck, USA) administered. After the calvarial defects were surgically created, the rats received a peritoneal alendronate(0.25mg/kg) in group I, a peritoneal alendronate(1.25mg/kg) in group II, and a peritoneal normal saline injection in the control group. Three and six weeks later, blood was sampled and evaluated for alkaline phosphatase activity. The animals were sacrificed for histological observation and histometric analysis of the level of bone formation. The alkaline phosphatase activity was similar in three groups at 3 weeks of experiment. The activity at 6 weeks increased more than twice, compared to 3 weeks, and was slightly higher in group I than the other two groups. In histological observation, all the groups at 3 weeks, osteoblast rimming and new bone formation were observed along the defect margin. At 6 weeks, the defect was almost closed with new and more mature bone, but new bone is thinner than original bone in the central portion of defect. In histometric analysis, group I and II at 3 weeks showed significantly greater new bone formation than the control, and all the groups at 6 weeks showed similar amount of bone formation. These result suggest that alendronate administration in the dose of 0.25mg/kg and 1.25mg/kg promote osseous regeneration.

• Archives of Craniofacial Surgery
• /
• v.12 no.2
• /
• pp.107-110
• /
• 2011

Purpose: There have been few case reports regarding treatment plans for long-term, neglected scalp defects and calvarial defects with subdural abscess. The purpose of this case report is to present our experience with a free latissimus dorsi musculocutaneous flap for scalp and calvarial defects and to discuss flap options in comparison with a literature review. Methods: A 60-year-old man who fell down from a four-story-height that resulted in a craniotomy in 1979; he visited our outpatient clinic for a chronic, purulent scalp and calvarial defects with unidentified artificial bone. The artificial bone was removed by a neurosurgeon and reconstructed with a free latissimus dorsi musculocutaneous flap. The deep temporal artery was used as a recipient artery. The postoperative flap status was excellent until the 6th day post-operation when the patient experienced a seizure, and an arterial insufficiency occurred at the flap probably due to an arterial spasm. Emergency exploration with arterial re-anastomosis was performed and the flap status was stabilized. Results: Complete wound healing was achieved after 3 weeks without infectious and systemic postoperative complications. During the 6 month follow-up period, there were no complications. Conclusion: We suggest the latissimus dorsi myocutaneous free flap as a good treatment option for a chronic, purulent, complicated scalp with calvarial defect, as a well as treatment for an acute traumatic defect.

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

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.32 no.4
• /
• pp.313-323
• /
• 2010

Purpose: This study was conducted to evaluate the effect of beta-tricalcium phosphate (Cerasorb$^{(R)}$, Germany) and deproteinized bovine bone (Bio-Oss$^{(R)}$, Switzerland) grafted to the defect of rat calvaria artificially created and the effect of use of absorbable membrane (BioMesh$^{(R)}$, Korea) on new bone formation. Materials and Methods: Transosseous circular calvarial defects with diameters of 5 mm were prepared in the both parietal bone of 30 rats. In the control group I, no specific treatment was done on the defects. In the control group II, the defects were covered with absorbable membrane. In the experimental group I, deproteinized bovine bone was grafted without absorbable membrane; in the experimental group II, deproteinized bovine bone was grafted with absorbable membrane; in the experimental group III, beta-tricalcium phosphate was grafted without absorbable membrane; in the experimental group IV, beta-tricalcium phosphate was grafted with absorbable membrane. The animals were sacrificed after 3 weeks and 6 weeks respectively, and histologic and histomorphometric evaluations were performed. Results: Compare to the control groups, the experimental groups showed more newly formed bone. Between the experimental groups, beta-tricalcium phosphate showed more resorption than deproteinized bovine bone. Stabilization of grafted material and interception of the soft tissue invasion was observed in the specimen treated with membrane. There was no statistical difference between the experimental group I, III and experimental group II, IV classified by graft material, but statistically significant increase in the amount of newly formed bone was observed in the experimental group I, II and II, IV classified by the use of membrane (P<0.05). Conclusion: Both beta-tricalcium phosphate and deproteinized bovine bone showed similar osteoconductibility, but beta-tricalcium phosphate is thought to be closer to ideal synthetic graft material because it showed higher resorption rate in vivo. Increased new bone formation can be expected in bone graft with use of membrane.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.26 no.6
• /
• pp.557-564
• /
• 2000

The bone graft materials can be grossly divided into autogenous bone, allogenic bone, xenogenic bone, and alloplastic material. Much care was given to other bone graft materials away from autogenous bone due to its additional operation for harvesting, delayed resorption and limitation of quantity. Demineralized freeze-dried bone(DFDB) and hydroxyapatite are the representatives of bone graft materials. As resorbable hydroxyapatite is developed in these days, the disadvantage of nonresorbability can be overcome. So we planned to study on the strength and the bone formation at the rats calvarial defects of DFDB graft and those of the composite graft with DFDB and resorbable hydroxyapatite. We used the 16 male rats weighting range from 250 to 300 gram bred under the same environment during same period. After we made the 6mm diameter calvarial defect, we filled the DFDB in 8 rats and DFDB and resorbable hydroxyapatite in another 8 rats. We sacrificed them at the postoperative 1 month and 2 months with the periostium observed. As soon as the specimens were delivered, we measured the compressive forces to break the normal calvarial area and the newly formed bone in calvarial defect area using Instron(Model Autograph $S-2000^{(R)}$, Shimadzu, Japan). The rest of the specimens were stained with H&E(Hematoxylin & Eosin) and evaluated with the light microscope. So we got the following results. 1. In every rats, there was no significant difference between the measured forces of normal bone area and those of the bone graft area. 2. In 1 month, the measured forces at DFDB graft group were higher than those of the DFDB and resorbable hydroxyapatite composite graft group(P<0.05). 3. In 2 months, there was no significant differences between the measured forces of DFDB graft group and those of the DFDB and resorbable hydroxyapatite composite graft group. 4. In lightmicroscopic examination, most of the grafted DFDB were transformed into bone in 1 month and a large numbers of hydroxyapatite crystal were observed in DFDB and resorbable hydroxyapatite composite graft group in 1 month. 5. Both group showed no inflammatory reaction in 1 month. And hydroxyapatite crystals had a tight junction without soft tissue invagination when consolidated with newly formed bone. 6. In both groups, newly formed bone showed the partial bone remodeling and the lamellar bone structures and some of reversal lines were observed in 2 months. From the above results, it is suggested that DFDB and resorbable hydroxyapatite composite graft group had a better resistance to compressive force in early stage than DFDB graft group, but there would be no significant difference between two groups after some period. And it is suggested that the early stage of bone formation procedure of DFDB and resorbable hydroxyapatite composite graft group was slight slower than that of DFDB graft group, but there would be no significant difference between two groups after some period.