• The Journal of the Korean dental association
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• v.54 no.5
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• pp.348-355
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• 2016

Ideal autogenous or allogenic bone graft materials should provide 1) stabilization of blood clot, 2) scaffolds for cellular proliferation and differentiation, 3) release of osteogenic growth factors, 4) appropriate resorption profile for remodeling of new bone. Teeth, especially dentin, mostly contain hydroxyapatite and type I collagen which are similar to bone, and could be valuable graft material. Clinically teeth are used as calcined or demineralized forms. Demineralized form of dentin can be more effective as a graft material. But a conventional decalcification method takes time and long treatment time may give negative effects to various osteogenic proteins in dentin. Author used a new clinical method to prepare autogenous teeth, which could be grafted into the removal defects immediately after extraction using vacuum ultrasonic system. The process could be finished within two hours regardless of the form (powder, chip or block). Teeth were processed to graft materials in block, chip, or powder types immediately after extraction. It took 120 minutes to prepare block types and 40 minutes to prepare powder. Clinical cases did not show any adverse response and the healing was favorable. Rapid preparation of autogenous teeth with the vacuum ultrasonic system could make the immediate one-day extraction and graft possible.

• Journal of Periodontal and Implant Science
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• v.45 no.2
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• pp.46-55
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• 2015

Purpose: This study evaluated the mechanical and structural properties of biphasic calcium phosphate (BCP) blocks processed using a modified extrusion method, and assessed their in vivo effectiveness using a rabbit calvarial defect model. Methods: BCP blocks with three distinct ratios of hydroxyapatite (HA):tricalcium phosphate (TCP) were produced using a modified extrusion method:HA8 (8%:92%), HA48 (48%:52%), and HA80 (80%:20%). The blocks were examined using scanning electron microscopy, X-ray diffractometry, and a universal test machine. Four circular defects 8 mm in diameter were made in 12 rabbits. One defect in each animal served as a control, and the other three defects received the BCP blocks. The rabbits were sacrificed at either two weeks (n=6) or eight weeks (n=6) postoperatively. Results: The pore size, porosity, and compressive strength of the three types of bone block were $140-170{\mu}m$, >70%, and 4-9 MPa, respectively. Histologic and histomorphometric observations revealed that the augmented space was well maintained, but limited bone formation was observed around the defect base and defect margins. No significant differences were found in the amount of new bone formation, graft material resorption, or bone infiltration among the three types of BCP block at either of the postoperative healing points. Conclusions: Block bone substitutes with three distinct compositions (i.e., HA:TCP ratios) processed by a modified extrusion method exhibited limited osteoconductive potency, but excellent space-maintaining capability. Further investigations are required to improve the processing method.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.5
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• pp.284-289
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• 2015

In cases of severe alveolar bone atrophy in the posterior maxillary area, which has only a thin sinus floor, the autogenous tooth bone graft block (ABTB) was used to wrap the implant to enhance its primary stability and osseointegration in the sinus. These cases with four years of clinical follow-up demonstrate the applicability of the ABTB in maxillary sinus membrane elevation to improve the outcomes of implant placement.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.28 no.2
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• pp.64-73
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• 2019

Various techniques have been developed, and the development of piezo electric devices have made it possible to widen the alveolar ridge even if the residual bone is dense or if there is a lack of cancellous bone between the cortical bones. In the operation of the mandibular posterior area, the flap is easily accessible to the ramus bone, from which high quality autogenous bone can be obtained, compared to other parts. A small autologous bone block can be used with particulated bone graft material using one screw for bone regeneration instead of a large autologous bone with two screws. The tapered implant design can minimize buccal bone fracture, even in severely atrophic mandibular areas. We report a case of 4 years following implant placement with ridge splitting and small autogenous bone graft in severly atrophic mandible. This report demonstrates a case of functional and aesthetic restoration in a patient through a collaboration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.6
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• pp.467-473
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• 2009

Purpose: The aim of this study is to compare volume and revascularization of autogenous block bone grafts in simultaneously cortical perforation of recipient beds and grafts, and only cortical perforation of recipient beds. Materials and methods: Two block bone in 8mm diameter was harvested in both skull using trephine bur on 20 New Zealand white rabbits. Harvested block bone was grafted on both inferior border of mandible. On the left side(experimental side), cortical bone of recipient beds and graft were perforated, and on the right side(control side), the only recipient bed was perforated. The rabbits had been sacrificed and infused the India ink for the observation of revascularization at 20 day and 40 day after surgery. The specimens were processed for H-E staining and quantitative analysis(independent t-test, p<0.01) was made under an optical microscope. In additional, specimens were processed for the observation of revascularization. Results: After 20 days, more bone volume was observed in experimental group, but no significant difference between two groups(p=0.106). There were significantly more bone volume in the experimental group at 40 days after surgery(p<0.01). After 20 days, more discrete vascular sprouts were observed in experimental side, but no difference at 40 days after surgery. Conclusion: We conclude that the cortical perforation of both the recipient beds and grafts improve revascularization at early stage and overall graft persistence.

• Journal of Korean Foot and Ankle Society
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• v.13 no.1
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• pp.68-74
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• 2009

Purpose: This study was designed to evaluate the results and efficacy of subtalar distraction two bone-block arthrodesis for calcaneal malunion. Materials and Methods: From January 2004 to June 2007, we operated on 8 patients (12 cases). There were 7 male patients and 1 female patient; their mean age was 42 years. 8 cases among them were operated initially. The period between initial injury and arthrodesis was 21 months. At an average follow up was 19 months. In operation, we used extensile lateral approach and arthrodesis was performed through tricortical two bone-block and cannulated screws. The Ankle-Hindfoot scale was used for clinical evaluation. In radiologic analysis, plain X-ray and CT were examined union and various parameters. Results: All cases achieved radiologic union at the final follow-up. The mean Ankle-hindfoot scale (maximum of 94 points) increased from 43.4 points preoperatively to 84 points at the final follow-up. The radiologic analysis of the pre- and postoperative standing lateral radiographs showed and average increase of 5.5 mm in talo-calcaneal height, $5.1^{\circ}$ in talocalcaneal angle, $6.1^{\circ}$ in talar declination angle and decrease of $5.7^{\circ}$ in talo-first metatarsal angle. Conclusion: The short term results of subtalar distraction two bone-block arthrodesis is promising, but longer follow-up was needed.

• Clinics in Shoulder and Elbow
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• v.26 no.3
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• pp.252-259
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• 2023

Background: The purpose of this study was to identify demographics and risk factors associated with unplanned 30-day readmission and reoperation following open procedures for shoulder instability and examine recent trends in open shoulder instability procedures. Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried using current procedural terminology (CPT) codes 23455, 23460, and 23462 to find patients who underwent shoulder instability surgery from 2015 to 2019. Independent sample Student t-tests and chi-square tests were used in univariate analyses to identify demographic, lifestyle, and perioperative variables related to 30-day readmission following repair for shoulder instability. Multivariate logistic regression modeling was subsequently performed. Results: In total, 1,942 cases of open surgical procedures for shoulder instability were identified. Within our study sample, 1.27% of patients were readmitted within 30 days of surgery, and 0.85% required reoperation. Multivariate logistic regression modeling confirmed that the following patient variables were associated with a statistically significant increase in the odds of readmission: open anterior bone block/Latarjet-Bristow procedure, being a current smoker, and a long hospital stay (all P<0.05). Multivariate logistic regression modeling confirmed statistically significant increased odds of reoperation with an open anterior bone block or Latarjet-Bristow procedure (P<0.05). Conclusions: Unplanned 30-day readmission and reoperation after open shoulder instability surgery is infrequent. Patients who are current smokers, have an open anterior bone block or Latarjet-Bristow procedure, or a longer than average hospital stay have higher odds of readmission than others. Patients who undergo an open anterior bone block or Latarjet-Bristow procedure have higher odds of reoperation than those who undergo an open soft-tissue procedure. Level of evidence: III.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.5
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• pp.224-229
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• 2014

The maxillary posterior area is the most challenging site for the dental implant. Although the sinus graft is a predictable and successful technique for rehabilitation of atrophic and pneumatized posterior maxilla, when there is severe destruction of alveolar bone, a very long crown length remains challenging after successful dental implants installation with sinus graft. We performed vertical augmentation of the maxillary posterior alveolar ridge using the allogenic block bone graft with a simultaneous sinus graft using allogenic and heterogenic bone chips. After about six months, we installed the dental implant. After this procedure, we achieved a more favorable crown-implant fixture ratio and better results clinically and biomechanically. This is a preliminary report of vertical augmentation of maxillary posterior alveolar ridge using allogenic block bone graft and simultaneous maxillary sinus graft. Further research requires longer observation and more patients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.4
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• pp.278-286
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• 2011

Introduction: This study examined the predictability of new bone formation in the pneumatized maxillary sinus using only fibrin-rich blocks with concentrated growth factors as an alternative to bone grafts. Materials and Methods: Maxillary sinus augmentation was performed in thirty-three patients with a deficient alveolar bone height (mean 3.9 mm). All patients were treated consecutively with sinus membrane elevation via the lateral window approach and panoramic radiograms and cone-beam computed tomograms were taken to evaluate the remaining bone height and the new bone formation in the maxillary sinus, before and after surgery. Four biopsy specimens were taken at the time of implant consolidation (after an average of five months healing) and were stained by H & E and Trichrome staining. Results: None of the patients had postoperative complications during implant consolidation. After an average of 5 months since sinus augmentation, newly formed bone was observed in all cases by a radiographic evaluation. In 4 biopsy samples, newly formed bone was observed along the floor of the replaced bony window. The osteoblast lining and well distinguished Osteocytes in the lacunas were observed in the newly formed bone. Of the 74 implants (4 different surfaced implants - resorbable blast media-surfaced (RBM), Hydroxyapatite (HA) coated, acid-etched, sintered porous-surfaced implant) placed, one RBM implant failed. The success rate was 98.6% after a mean of 15 months. Discussion: These results suggest that maxillary sinus augmentation using fibrin rich block with concentrated growth factors is a successful and predictable technique.

• The Journal of the Korean dental association
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• v.57 no.12
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• pp.768-777
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• 2019

Alveolar bone resorption are unpredictable and always occur after tooth extraction. Such bone resorption causes insufficient alveolar ridge which make implant placement difficult. There are many techniques to increase the alveolar ridge. Representative procedures include ridge split, guided bone regeneration, bone graft using autogenous block bone, and alveolar distraction. In each procedure, there are indications and complications. Depending on the shape and the width of bone defects, we can choose procedures for horizontal bone augmentation and vertical bone augmentation.