• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.283-290
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• 2000

State ment of Problems. Although some clinicians report long-term success with fixed partial denture (FPD) that contain cantilever pontic, the use of cantilever FPDs may be hazardous because of unfavorable leverages during mastication. Purpose of Study. This study aims to compare the stress induced in the periodontium with normal and reduced bone support, and to analyze the stress distribution patterns of anterior cantilevered FPDs using the finite element method. Results. Cantilever bridge with a reduced bone level generated the highest peak stresses in the periodontium. In the models of reduced bone support, a cantilever bridge exhibited the great-est mobility and a 3-unit fixed restorations induced the smallest mobility of canine. The highest peak stress level of a 3-unit bridge in the periodontium is similar to the unrestored situation. But stress distribution in the bone is modified. Conclusion. In reduced bone support, a cantilever bridge exhibited the greatest mobility and stress.

• The korean journal of orthodontics
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• v.31 no.6 s.89
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• pp.601-610
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• 2001

The purpose of this retrospective study was to evaluate the level oi alveolar bone support of the erupted Permanent canine through the reconstructed cleft region compared to the contralateral canine on the non-cleft side. This study was limited to children with complete unilateral cleft lip and palate who underwent secondary alveolar iliac bone gvaft and the apices of the erupted canine roots were closed at the time of evaluation. With these criteria the study included 21 children whose average age at the time of bone graft reconstruction was 9.8 years, with a minimum of 12.4 years of age at the time of the evaluation. The study was limited to the use of iliac cancellous bone as the autograft material for reconstruction of the alveolar cleft. Cranial bone graft and other autogenous bone sources were excluded. The periapical radiographs were used to evaluate alveolar bone level of each canine. The percentages of root supported by the bone were established by dividing the amount of root covered with the bone by the anatomic root length. The canine oi the non-cleft side was used as an internal control and the canine on the cleft side was used as an experimental. There was a statistically significant difference in the alveolar bone support ratio between the control ($92.9\%$) and experimental canines ($8.7\%$). An average of $95\%$ level of alveolar bone support was achieved for the experimental canine in comparison to the control canine. Neither the presence of lateral incisor, nor the stage of root development of the canine at the time of the bone graft appeared to have affected the alveolar bone support ratio of the canine after the secondary bone graft.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.229.1-229.1
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• 2003

Recently, the barrier membranes have been applied for regenerating bone surrounding peri-implant defects in guided bone regeneration(GBR). GBR membrane should provide mechanical support sufficient to withstand in vivo forces and maintain wound space for bone regeneration. The ability to exclude unwanted tissues of cells(connective tissue and epithelium) is needed. In addition large surface area is conductive to tissue ingrowth. The search for ideal materials that biocompatible, bioresorbable and can support the growth and phenotypic expression of osteoblasts is a major challenge in the biomedical application for the repair of bone defects. (omitted)

• Archives of Plastic Surgery
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• v.39 no.6
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• pp.612-617
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• 2012

Background Packing after closed reduction of a nasal bone fracture causes inconvenient nasal obstruction in patients. We packed the superior meatus with Vaseline gauze to support the nasal bone, and packed the middle nasal meatus with a Doyle Combo Splint consisting of an airway tube, a silastic sheet, and an expandable sponge to reduce the inconvenience. In addition, we aimed to objectively identify whether this method not only enables nasal respiration but also sufficiently supports the reduced nasal bone. Methods Nasal ventilation was measured via spirometry 1 day before surgery and compared to 1 day after surgery. To compare support of the reduced nasal bone by the 2 methods, 2 plastic surgeons assessed the displacementon X-rays taken after the surgery and after removing the packing. The extent of nasal obstruction, dry mouth, sleep disturbance, headache, and swallowing difficulty were compared with visual analog scales (VAS) on a pre-discharge survey. Results In the experimental group, the nasal respiration volume 1 day after surgery remained at $71.3%{\pm}6.84%$ on average compared to 1 day prior to surgery. Support of the reduced bone in the experimental group ($2.80{\pm}0.4$) was not significantly different from the control group ($2.88{\pm}0.33$). The VAS scores for all survey items were lower in the experimental group than in the control group, where a lower score indicated a lower level of inconvenience. Conclusions The nasal cavity packing described here maintained objective measures of nasal respiration and supported the reduced bone similar to conventional methods. Maintaining nasal respiration reduced the inconvenience to patients, which demonstrates that this packing method is useful.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.5
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• pp.482-487
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• 2006

As the uses of dental implants are prevailing, the need for sinus bone graft is increasing. Deproteinized bovine bone mineral (DBBM) was not mentioned in 1996 Sinus Bone Graft because of the deficit of the available data. Since then, many clinical and laboratory reports support the use of DBBM in the sinus bone graft procedure. In this report, the histological and clinical successes of sinus bone grafting with DBBM is discussed with available literatures. After sinus bone grafts with DBBM, the proportion of new bone formed was similar or superior to natural maxillary posterior alveolar bone after healing period of 6 months to 1 year. It seems that the grafted DBBM is not be either resorbed nor replaced with bone, but this may not disturb the osseointegration of dental implants installed into it. The clinical survival rates of dental implants installed on the sinus grafted with DBBM was similar to those installed on the ungrafted posterior maxillary alveolar ridge or grafted with autogenous bone. So, it can be concluded that DBBM can be used successfully in the sinus bone graft.

• Journal of Nutrition and Health
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• v.29 no.6
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• pp.590-593
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• 1996

This study was done to evaluate the effect of dietary calcium level (a diet which met 100% or twice the calcium level in AIN-76 diet) on preventing bone loss in ovariectomized rats. Forty Sprauge-Dawley female rats(body weight 200$\pm$5g)were divided into two groups. One group were ovariecotomized (Ovx) while the others received sham operation(Sham). Thereafter, each rat group was further divided into normal calcium diet(0.52%) and high calcium diet(1.04%) subgroups. All rats were fed on experimental diet and deionized water ad libitum for 8 weeks. The total body, spine and femur bone mineral densities and bone mineral contents were measured by Dual Energy X-ray Absorptiometry, Eight weeks following operation, ovariectomized rats fed a high calcium diet had a significantly higher total bone mineral content, total bone calcium content, spine bone mineral density, spine bone mineral content and femur bone mineral content than ovariectomized rats fed control calcium diet. The correlation between dietary calcium intake level and spine bone mineral density were positive, but there was no correlation between dietary calcium intake and femur bone mineral density. The findings from the present study demonstrated that bone loss due to ovarian hormonal deficiency can be partially prevented by a high calcium diet. Futhermore, these findings support the strategy of the use of a high calcium diet in the prevention of estrogen depleted bone loss(postmenopausal osteoporosis)

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1368-1372
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• 2003

PMMA which is used as the bone cement for vertebroplasty is able to be a supporter, as a fixing supporter role, for broken trabecular structure, caused by the compressed fracture of spine on aged osteoporosis. In this thesis, as experimenting apparent density of bone pieces, we have figured out support extent of Young's modulus as classifying the bone pieces injected PMMA and the others which are not. In case of low apparent density of PMMA in some bone, Young's modulus seems to be more supportable to bone. On the other hand, if apparent density of bones is normal, injection of PMMA is not very effective on improvement in Young's modulus of bone cement injection.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.9-15
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• 1991

The cleft alveolus occurs about 75% of cleft lip and palate patients. The purpose of bone grafting is improve the maxillary growth, rehabilitation of continuty of maxillary arch and providing bone for periodontal support for unerupted teeth. The bone grafting for alveolar cleft defect repair are classsified; primary bone grafting, early secondary bone grafting secondary bone grafting and late secondary bone grafting. In this article, we reported the cases of PMCB grafts for repair of the alveolar clefts showed potential benifit to the patient to induce a normal maxillary growth and providing bone foor periodontal support of unerupted teeth.

• Archives of Plastic Surgery
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• v.44 no.3
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• pp.188-193
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• 2017

Alveolar cleft is a tornado-shaped bone defect in the maxillary arch. The treatment goals for alveolar cleft are stabilization and provision of bone continuity to the maxillary arch, permitting support for tooth eruption, eliminating oronasal fistulas, providing an improved esthetic result, and improving speech. Treatment protocols vary in terms of the operative time, surgical techniques, and graft materials. Early approaches including boneless bone grafting (gingivoperiosteoplasty) and primary bone graft fell into disfavor because they impaired facial growth, and they remain controversial. Secondary bone graft (SBG) is not the most perfect method, but long-term follow-up has shown that the graft is absorbed to a lesser extent, does not impede facial growth, and supports other teeth. Accordingly, SBG in the mixed dentition phase (6-11 years) has become the preferred method of treatment. The most commonly used graft material is cancellous bone from the iliac crest. Recently, many researchers have investigated the use of allogeneic bone, artificial bone, and recombinant human bone morphogenetic protein, along with growth factors because of their ability to decrease donor-site morbidity. Further investigations of bone substitutes and additives will continue to be needed to increase their effectiveness and to reduce complications.