• The Journal of Korean Academy of Prosthodontics
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• v.37 no.5
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• pp.687-697
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• 1999

A finite element analysis has been utilized to analyze stress and strain fields and design a new configuration in orthopedics and implant dentistry. Load transfer and stress analysis at implant bone interface are important factors from treatment planning to long term success. Bone configuration and quality are different according te anatomy of expecting implantation site. The purpose of this study was to compare the stress distribution in maxilla and mandible accord-ing to implant length and bone engagement types. A three dimensional axi-symmetric implant model(Nobel Biocare, Gothenburg, Sweden) with surrounding cortical and cancellous bone were designed to analyze the effects of bone engagement and implant length on stress distribution. ANSYS 5.5 finite element program was utilized as an interpreting toot. Three cases of unicortical anchorage model with 7, 10, 13 mm length and four cases of bicortical anchorage model with 5, 7, 10 and 13 mm length were compared both maxillary and mandibular single implant situation. Within the limits of study, following conclusions were drawn. 1. There is a difference in stress distribution according to cortical and cancellous bone thickness and shape. 2. Maximum stress was shown at the top of cortical bone area regardless of bone engagement types. 3. Bicortical engagement showed less stress accumulation when compared to unicortical case overall. 4. Longer the implant future length, less the stress on cortical bone area, however there is no difference in mandibular bicortical engagement case.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.3
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• pp.229-235
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• 2010

Purpose: This study examined the significance of increased bone density according to time after implantation on maxilla using demographic data with CBCT and compared the bone density between before vs. after implantation using the Hounsfield index. Materials and Methods: Twenty-five implant site on maxilla were selected. Cone-beam computerized tomography (CBCT) scans were used for the analysis. The implant sites were evaluated digitally using the Hounsfield scale with EzImplant TM and the results were compared over time. Statistical data over time was carried out to determine the correlation between the recorded Hounsfield unit (HU) over time and gender difference using repeated ANOVA. Results: The bone density of implantation site over time showed an increase in the HU mean values. Immediately after implantation, bone density was significantly increased than bone density before implantation. Until 6 month follow-up, bone density showed stable increasement. There is no significant difference on gender. Conclusions: Using CBCT, bone density increased over time after implantation on maxilla. Bone density measurements using CBCT might provide an objective assessment of the bone quality as well as the correlation between bone density and stability of implant.

• Journal of Hospice and Palliative Care
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• v.17 no.4
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• pp.207-215
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• 2014

Multiple bone metastases are common manifestation of many malignant tumors such as lung cancer, breast cancer, prostate cancer and renal cell carcinoma. Bone metastasis is secondary cancer in the bone, and it can lead to bone pain, fracture, and instability of the weight bearing bones, all of which may profoundly reduce physical activity and life quality. Treatment for bone metastasis is determined by multiple factors including pathology, performance status, involved site, and neurologic status. Treatment strategies for bone metastasis are analgesics, surgery, chemotherapy and radiotherapy. External beam radiotherapy has traditionally been an effective palliative treatment for localized painful bone metastasis. However, in some cases such as multiple bone metastases, especially osteoblastic bone metastasis originated from breast or prostate cancer, the radiopharmaceutical therapy using $^{89}Sr$, $^{186}Re$, $^{188}Re$, $^{153}Sm$ and $^{117m}Sn$ are also useful treatment option because of administrative simplicity (injection), few side effects, low risk of radiation exposure and high response rate. This article offers a concise explanation of the radiopharmaceutical therapy for multiple bone metastases.

• Journal of Periodontal and Implant Science
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• v.39 no.2
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• pp.185-192
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• 2009

Purpose: The aim of this study was to examine the correlation of the subjective and the objective evaluation of edentulous ridge bone quality, and to evaluate the change of the dental implant stability in each bone density group for early healing period after implant installation. Methods: Sixty-seven implants(Osstem implant$^{(R)}$, Seoul, Korea) were included in this study. We evaluated the bone density by 2 methods. The one was the subjective method which was determined by practitioner s tactile sense, the other was the objective bone type was based on Hounsfield units. The implant stability in each bone type group was assessed by resonance frequency analyzer(Osstell mentor$^{(R)}$). Data were analyzed for the change of the implant stability, and they were compared to verify the difference of groups at the time of installation, 2, 6, 10, 14 weeks postoperatively. Spearman's correlation was used to demonstrate the correlation between the subjective and the objective evaluation of the bone density, and analysis of variance(ANOVA) was used to analyze the differences of implant stability at each time point. Results: There was no close relation between the subjective and the objective evaluation of the bone density(r=0.57). In the subjective groups, there was statistically significant difference between the type 1 and 3 at 10 weeks and between the type 2 and 3 at 14 weeks. In the objective groups, there was no statistically significant difference between the D 1, 2, 3, 4, and 5 group with regard to RFA from baseline to 14 weeks(P>0.1). Conclusions: The implant stability increased over time during the study, and it was improved with bone density proportionally after 2weeks postoperatively. It is recommended that the decision of bone density is base on Hounsfield unit for implant loading time.

• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.195-210
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• 2006

The aim of this study is to evaluate the effects of combination of rhBMP-4 and chitosan, which have osteoinductive capacity, on the regeneration of bone defects in dogs. Three beagle dogs aged over one and half years and weighed about 15Kg were used in this study. Three round defects were made by trephine bur in each side of mandibles. Each defect was filled with collagen, chitosan, rhBMP-4/chitosan. The dogs were sacrificed at 1, 3 or 8 weeks postsurgery and the results were evaluated histologically. The results of this study were as follows: 1. The sign of new bone formation, rearrangement of osteoblasts was revealed adjacent of preexisted bone or around graft materials such as chitosan. 2. The descending order of groups in bone regeneration speed was the rhBMP-4/chitosan group, chitosan group, collagen group. In the combination group, new bone was regenerated more and in better quality than others. 3. The regeneration of bone was observed in the rhBMP-4/chitosan group in 3 weeks after surgery. In 8 weeks after surgery, bone regeneration was observed in all three groups, and new bone at 8th week was denser in the chitosan and rhBMP-4/chitosan group than collagen group. In conclusion, rhBMP-4 and chitosan can be applied in the bone regeneration procedures usefully. It is considered that chitosan can be a splint for the maintenance of the defect form and produce much better effect when used with good grafting material or bone morphogenetic protein.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.1
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• pp.29-33
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• 2019

Objectives: Bone density seems to be an important factor affecting implant stability. The relationship between bone density and primary and secondary stability remains under debate. The aim of this study was to compare primary and secondary stability measured by resonance frequency analysis (RFA) between different bone types and to compare implant stability at different time points during 3 months of follow-up. Materials and Methods: Our study included 65 implants (BioHorizons Implant Systems) with 3.8 or 4.6 mm diameter and 9 or 10.5 mm length in 59 patients. Bone quality was assessed by Lekholm-Zarb classification. After implant insertion, stability was measured by an Osstell device using RFA at three follow-up visits (immediately, 1 month, and 3 months after implant insertion). ANOVA test was used to compare primary and secondary stability between different bone types and between the three time points for each density type. Results: There were 9 patients in type I, 18 patients in type II, 20 patients in type III, and 12 patients in type IV. Three implants failed, 1 in type I and 2 in type IV. Stability values decreased in the first month but increased during the following two months in all bone types. Statistical analysis showed no significant difference between RFA values of different bone types at each follow-up or between stability values of each bone type at different time points. Conclusion: According to our results, implant stability was not affected by bone density. It is difficult to reach a certain conclusion about the effect of bone density on implant stability as stability is affected by numerous factors.

• Culinary science and hospitality research
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• v.19 no.4
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• pp.231-242
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• 2013

This study was performed to develop cod bone stock using various nutritional elements in cod bone with the addition of various amounts of tomatoes (2%, 4%, 6% and 8%). Moisture contents, pH, L value and Na contents decreased, while the salinity, sugar contents, a value, b value and Mg, K, Ca, Fe contents increased with increased rates of tomatoes. Fourteen types of free amino acid were detected, and stock containing 6% of tomato addition had the highest free amino acid content. In the test on different attributes, tomato content significantly affected the properties of the stock including color intensity, savory flavor, tomato flavor, tomato taste, savory taste and after taste. In the acceptance test, 6% of tomato addition was preferred for appearance, flavor, taste, texture and overall quality. Consequently, the optimal tomato content for maximizing the overall quality of cod bone stock was 6%.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8401-8404
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• 2014

Background: To determine survival times of cervical cancer patients with bone metastasis related to the effect of age at the time of cervical cancer diagnosis, we performed the retrospectively analytical study. Methods: A total of 68 cervical cancer patients with bone metastasis were treated at a single hospital, during January 1998 to December 2010. Fifty-two medical records were identified and collected, the remaining sixteen medical records were not found. Main outcome measures were patient characteristics, clinical information, duration from cervical cancer diagnosis to bone metastasis diagnosis, survival time after bone metastasis and overall survival time. Results: Among fifty-two cervical cancer patients with bone metastasis, there were 13 patients who were less than 45 years old, and 39 patients were 45 years old or more at the time of cervical cancer diagnosis. The younger group had less median overall survival than the older group, with a statistically significant difference (21 months, 95% CI 19.93-22.06; 34 months, 95% CI 23.27-44.72, p = 0.021). However, they were comparable in the duration from cervical cancer diagnosis to bone metastasis diagnosis and the survival time after bone metastasis. Conclusion: Young patients with bone metastasis aged less than 45 years old at the time of cervical cancer diagnosis have a poorer prognosis than the elderly patients. Impact: To improve survival and quality of life, more intensive and novel multimodal treatments at the time of cervical cancer diagnosis should be considered in patients less than forty-five years, who can tolerate the side effects better.

• Journal of Periodontal and Implant Science
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• v.39 no.2
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• pp.149-156
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• 2009

Purpose: Deproteinized bovine bone substitutes are commonly used in dental regenerative surgery for treatment of alveolar defects. In this study, three different bovine bone minerals - OCS-B (NIBEC, Seoul, Korea), Bio-Oss (Geistlich - Pharma, Switzerland), Osteograft/N - 300 (OGN, Dentsply Friadent Ceramed. TN, USA) - were investigated to analyze the basic characteristics of commercially available bone substitutes. Methods: Their physicochemical properties were evaluated by scanning electron microscopy, energy dispersive X-ray spectrometer (EDS), surface area analysis, and Kjeldahl protein analysis. Cell proliferation and alkaline phosphatase (ALP) activity of human osteosarcoma cells on different bovine bone minerals were evaluated. Results: Three kinds of bone substitutes displayed different surface properties. Ca/P ratio of OCS - B shown to be lower than other two bovine bone minerals in EDS analysis. Bio-Oss had wider surface area and lower amount of residual protein than OCS - B and OGN. In addition Bio - Oss was proved to have lower cell proliferation and ALP activity due to lots of residual micro particles, compared with OCS - B and OGN. Conclusions: Based on the results of this study, three bovine bone minerals that produced by similar methods appear to have different property and characteristics. It is suggested that detailed studies and quality management is needed in operations for dental use and its biological effects on new bone formation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.6
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• pp.554-560
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• 2008

In posterior maxilla, it is difficult to achieve primary stability of implants due to sinus pneumatization, alveolar bone loss, and low bone quality. The accurate and objective primary stability assessment is important for good prognosis of implants. Purpose: The aim of this study was to assess the primary stability of the non-submerged, internal type implants with maxillary sinus augmentation using deproteinized bovine bone mineral by a resonance frequency analyzer, when residual alveolar bone height is under 8mm Materials and methods: A total of 20 implants was placed into 5 grafted maxillary sinuses in 5 patients. Deproteinized bovine bone mineral (Bio-$Oss^{(R)}$) was used as graft material. SS II implants (diameter 4.1mm, and length 11.5mm, SLA suface)) were placed. All of the patients received maxillary sinus graft procedure by 1-step technique. Residual bone height was $1.3{\sim}7.8mm$ (mean 4.4mm) measured by panorama radiography. After implant placement, RFA was measured at 4,8,12,20 weeks. The results were divided into 2 groups; RFA value under 4mm and over 5mm of bone height. It was statistically analyzed. Results: 1. The primary stability of implants was increased with time 2. The RFA value was above 65 ISQ at 12 weeks 3. There was no correlation between RFA and residual alveolar bone height in maxillary sinus augmentation by 1-step technique. Conclusion: 1-step surgical procedure is a feasible option for patients with as little as 4mm residual alveolar bone height, when utilizing non-submerged, internal type implants with xenografts.