• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.42
• /
• pp.34.1-34.7
• /
• 2020

Purpose: The purpose of this study was to evaluate the influence of biodegradable polycaprolactone membrane on new bone formation and the biodegradation of biphasic alloplastic bone substitutes using animal models. Materials and methods: In this study, bony defect was formed at the canine mandible of 8 mm in diameter, and the defects were filled with Osteon II. The experimental groups were covered with Osteoguide as barrier membrane, and the control groups were closed without membrane coverage. The proportion of new bone and residual bone graft material was measured histologically and histomorphometrically at postoperative 4 and 8 weeks. Results: At 4 weeks, the new bone proportion was similar between the groups. The proportion of remaining graft volume was 27.58 ± 6.26 and 20.01 ± 4.68% on control and experimental groups, respectively (P < 0.05). There was no significant difference between the two groups in new bone formation and the amount of residual bone graft material at 8 weeks. Conclusion: The biopolymer membrane contributes to early biodegradation of biphasic bone substitutes in the jaw defect but it does not affect the bone formation capacity of the bone graft.

• Journal of Periodontal and Implant Science
• /
• v.35 no.3
• /
• pp.703-718
• /
• 2005

The purpose of this study was to evaluate the clinical efficacy of guided tissue regeneration(GTR) technique using chitosan nanofiber membrane and to compare it to the clinical efficacy following GTR using PLA/PLGA(copolymer of polvlactic acid and polylacticglycolic acid) membrane in mandibular class II furcation defects in human. The chitosan nanofiber membranes were applied to the mandibular class II furcation defects of 13 patients(test group) and PLA/PLGA membranes were applied to those of 11 patients(control group). Probing pocket depth, clinical attachment level, gingival recession, plaque index and gingival index were measured at baseline and 3 months postoperatively. Vertical and horizontal furcation defect depth were measured at surgery. Both groups were statistically analyzed by Wilcoxon signed Ranks Test and Mann-Whitney Test using SPSS program. The results were as follows: 1. Probing pocket depth, clinical attachment loss and gingival index were significantly reduced at 3 months postoperatively compared to values of baseline in both groups(p<0.05). 2. Gingival recession and plaque index were not significantly decreased at 3 months postoperatively compared to values of baseline in both groups. 3. No significant difference between two groups could be detected with regard to changes of probing pocket depth, gingival recession, clinical attachment level, plaque index and gingival index at 3 months postoperatively. In conclusion, chitosan nanofiber membrane is effective in the treatment of human mandibular class II furcation defects and a longer period study is needed to fully evaluate the outcomes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.50 no.4
• /
• pp.235-240
• /
• 2024

Lipomas, the most common soft-tissue mesenchymal neoplasms in adults, are characterized by the proliferation of mature white adipocytes without cytologic atypia. Lipomas are rarely observed in the head and neck region. We present a case of resection and orthognathic surgical removal of an intramuscular lipoma of the mandible with involvement of the mandibular ramus and condylar head and neck. An 18-year-old female patient was referred to our hospital for orthognathic surgery for the management of facial asymmetry and mandibular prognathism. The patient did not present with facial swelling, pain, or temporomandibular dysfunction; however, on radiographic examination, including cone-beam computed tomography and magnetic resonance imaging, an infiltrative fatty lesion was observed in the masticator space inside the right mandible, and the adjacent mandible exhibited bone thinning and deformity. Resection of the lipoma was performed along with orthognathic surgery, including a Le Fort I osteotomy for the maxilla and bilateral sagittal split ramus osteotomy (BSSRO). In this case, because the ramus was split using BSSRO, accessing the lipoma intraorally was easy. Consequently, aesthetic scarring was avoided, and no complications, such as unfavorable splitting or pathologic fracture, occurred. Although recurrence has not been observed about 1 year, long-term follow-up should be performed.

• Journal of Periodontal and Implant Science
• /
• v.42 no.2
• /
• pp.50-58
• /
• 2012

Purpose: This study evaluated histologically the tissue responses to and the effects of a customized nano-hydroxyapatite (n-HA) block bone graft on periodontal regeneration in a one-wall periodontal-defect model. Methods: A customized block bone for filling in the standardized periodontal defect was fabricated from prefabricated n-HA powders and a polymeric sponge. Bilateral $4{\times}{\times}4{\times}5$ mm (buccolingual width${\times}$mesiodistal width${\times}$depth), one-wall, critical-size intrabony periodontal defects were surgically created at the mandibular second and fourth premolars of five Beagle dogs. In each dog, one defect was filled with block-type HA and the other served as a sham-surgery control. The animals were sacrificed following an 8-week healing interval for clinical and histological evaluations. Results: Although the sites that received an n-HA block showed minimal bone formation, the n-HA block was maintained within the defect with its original hexahedral shape. In addition, only a limited inflammatory reaction was observed at sites that received an n-HA block, which might have been due to the high stability of the customized block bone. Conclusions: In the limitation of this study, customized n-HA block could provide a space for periodontal tissue engineering, with minimal inflammation.

• Journal of Periodontal and Implant Science
• /
• v.26 no.1
• /
• pp.1-26
• /
• 1996

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

• Journal of Periodontal and Implant Science
• /
• v.27 no.1
• /
• pp.61-78
• /
• 1997

PDGF-BB has been recognized as a highly potential growth factor for guided tissue regeneration in periodontal defect. This study carried out histologic and histometric evaluation of $200ng/cm^2$ PDGF-BB loaded bioresorbable membrane made from polyglycolic and polylactic acid. It was tested for its biocompatibility, ability to prevent epithelial downgrowth and amount of periodontal regeneration. Without membrane and PDGF-BB unloaded bioresorbable membrane were used as control. Healthy six beagle dogs were used. Each dog was anesthetized and buccal flaps were reflected in the mandibular and maxillary premolar areas. Buccal alveolar bone between the mesiobuccal and distobuccal line angles was surgically removed on the lower 2nd and 4th premolar in mandible, 2nd premolar in maxilla, to a level 4mm apical to the cementoenamel junction with creating a Class II buccal furcation defect for available space. Care was taken not to remove the root cementum layer and rubber impression materials were placed over each surgically created defect. Flaps were repositioned and sutured. Reconstructive surgery was performed 1 month after defect preparation. PDGF-BB loaded membranes and controls were randomly placed on maxillary 2nd premolars and mandibular 2nd and 4th premolars. Plaque control regimen was instituted with daily brushing with a 0.1% chlorhexidine digluconate during experimental periods. The animals were sacrificed 2 and 5 weeks after surgery and undecalcified specimens were prepared for histologic evaluation. The degree of coronal regrowth of new bone, new cementum and the amonut of new bone areas formed on the defected area of the PDGF-BB loaded membrnae turned superior to without membrane and drug unloaded membrane. Experimental membrane could prevent the epithelial downgrowth irrespective of drug loaded or not and showed good biocompatiblity, These results implicated that PDGF-BB loaded bioresorbable membrane could be highly useful tool for guided tissue regeneration of periodontal defects.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.35 no.5
• /
• pp.294-301
• /
• 2013

Purpose: The purpose of this study is to assess the effectiveness of beta-tricalciumphosphate (${\beta}$-TCP) as a bone graft material on new bone formation and regeneration of mandible bone defect around dental implants. Methods: Both mandibular sites of ten rabbits were exposed. The experimental subjects were divided into two groups. Rabbits in the control group (right site of the mandible) had dental implants around cortical bone defects, without treatment, while, in the experimental group (left site of the mandible), ${\beta}$-TCP was grafted into the bone defect around the implant. Rabbits were sacrificed after one, two, three, four, and eight weeks, and histomorphometric evaluation and analysis of the bone implant contact rate were performed using an optical microscope. Results: Bone formation rates in the experimental group were greater than those in the control group from one to eight weeks, and percentages of implant surface contacted to bone were greater in the experimental group than in the control group from three weeks after implantation. Conclusion: These results suggest that the bone formation activity around dental implants was increased by osteoconduction activity of ${\beta}$-TCP.

• The Journal of the Korean dental association
• /
• v.54 no.5
• /
• pp.365-373
• /
• 2016

Purpose: Cemental tear is a specific type of root surface fracture characterized by a complete separation of a cemental fragment along the cementodentinal junction or a partial split within the cementum along an incremental line. It is suggested to be a factor for periodontal or periapical tissue destruction. The aim of this study is to present a diagnosis and treatment of cemental tear associated with periapical lesion with root canal treatment and regenerative periodontal surgery. Treatments: A 60-year-old male who had a history of sports trauma on the mandibular right central incisor about 10 years ago presented with apical cemental tear. Clinical examination showed a slightly dark yellowish discoloration and sinus tract that was located on the apical labial mucosa. The mobility and percussion were also assessed on the diseased tooth and recorded as $Miller^{\circ}{\phi}s$ Class II and tenderness to percussion. The probing depth was within the normal limit (<3 mm). Radiographic examination revealed a radiolucent lesion at the apical area and extended to distal aspect of the tooth along the fragment of cemental tear. After root canal treatment, periapical surgery was performed. The bony defect was exposed and then the detached root fragment was removed. Apical root resection and retrograde filling with Mineral Trioxide Aggregate (MTA) were accomplished and the bony defect was filled with deproteinized bovine bone mineral (DBBM) and covered with biodegradable collagen membrane. Results: After 9-month follow-up, healing of the mandibular right central incisor was uneventful and no swelling, purulence or pain was revealed in the associated area. Probing pocket depth was favorably stable, and the tooth mobility was decreased to the Miller's Class I. Conclusions: Apical cemental tear associated periapical lesion could be successfully treated with removal of the detached cementum in combination with apical surgery and GTR procedure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.26 no.6
• /
• pp.613-619
• /
• 2000

The purpose of the present study was to investigate the effect of Bioactive glass on bone regeneration in the experimental mandibular bone defects. Five rabbits, weighing about 2.0kg, were used. Three artificial bone defects, $5{\times}5{\times}5mm$ in size, were made at the inferior border of the mandible. In the experimental group 1, the bone defect was grafted with $Biogran^{(R)}$ and covered with $Bio-Gide^{(R)}$ resorbable membrane. In the experimental group 2, $Biogran^{(R)}$ was grafted only. In the control group, the bone defect was filled with blood clot and was spontaneously healed. The animals were sacrificed at 1, 2, 4, and 8 weeks after the graft. Microscopic examination was performed. Results obtained were as follows: In the control group, the osteoid tissue was observed at week 1 and the bone trabeculi were connected each other and matured at week 2. The lamellar bone formation appeared at week 4, and the amount of bone tissue was increased at week 8. In the experimental group 1, the fibrous tissue was filled between the granules of Bioactive glass and the cartilage formation was found adjacent to the normal bone at week 1. The bone tissue was formed between the granules at week 2, while the amount of bone tissue increased and the lamellar bone formation was observed at week 4. The lamellar bone was increased at week 8. Histologic findings were Similar between the experimental groups 1 and 2, although the amount of Bioactive glass granules lost was increased in the latter. These results suggest that new bone formation is found around the Bioactive glass granules grafted into the bone defects, and the membrane plays a role in keeping the granules and preventing the fibrous tissue invasion.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.21 no.1
• /
• pp.60-64
• /
• 1999

Recently, for the reconstruction of bony defect and cosmetic improvement, many graft materials and implants have been widely used in the various surgical situations. The alloplastic materials have many advantages such as simplicity of operation, no additional need of surgery, and easy manipulation. The $Medpor^{TM}$(porous high-density polyethylene, Porex Co., USA) was initially studied in 1972 for surgical implant and introduced as an implant material for oral and maxillofacial region by Sauer and King in 1988. This material permits full ingrowth of bone into the implants, substantially increasing the implant's incorporation into the recipient site. It can be shaved during the surgery, which results in an improvement and prefabricated various size and shapes to fit into the surgical defect. The $Medpor^{TM}$ was used in 32 patients from 1995 to 1997 at the maxillofacial region. It was used for paranasal augmentation in 24 cases, for malar augmentation in 2 cases, for infraorbital augmentation in 2 cases, for mandibular angle augmentation in 2 cases, for mandibular body augmentation in 2 cases, for chin vertical augmentation in 1 case. It was mainly fixed with miniplate or screw. There were few complications except one infection and one exposure of the implant.