• 대한치과의사협회지
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• 제54권3호
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• pp.198-205
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• 2016

The purpose of this paper was to investigate the significance of splinted and non-splinted implant-supported restorations with an internal connection for multiple consecutively missing teeth. Upon examination of the effects of fixture-abutment connection, the distribution of occlusal load was favorable in splinted implant-prosthesis with an external connection, but effect of strain distribution was not significant in splinted implant-prosthesis with an internal connection. In splinted implant-prostheses for short implants, strain distribution was not affected by the method of retention. For cement-retained prostheses, the effect of strain distribution due to splinting was not significant. In clinical studies, non-splinted prostheses with an internal connection for multiple consecutively missing teeth showed high survival rate, mild marginal bone loss, and stable periodontal condition. However, failure to achieve optimal proximal contact between single-unit prostheses may lead to food impaction, and veneer fracture may be inevitable when the framework provides inadequate support in the proximal region. In conclusion, splinted implant-prosthesis is not an indication in all cases, and clinical consideration of its use should be based on the patient's oral condition, such as location and number of implants, formation of proximal contact, canine guidance, existence of parafunctional habit, and oral hygiene, when multiple consecutively missing teeth are replaced by internal connection type implant.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권4호
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• pp.292-298
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• 2020

Sinus Schneiderian membrane elevation surgery is widely performed for dental implant placement in the maxillary posterior region. With regard to sinus elevation surgery, various complications can occur and lead to implant failure. For successful implants in the maxillary posterior region, the clinician must be well acquainted with sinus anatomy and pathology, a variety of bone graft materials, the principles of sinus elevation surgery, and prevention and management of complications.

• 대한치과보철학회지
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• 제45권1호
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• pp.48-59
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• 2007

Statement of problems: There are few studies which reported the survival rates of the specific dental implant systems in the Korean population with the follow-up periods longer than 5 years. Purpose: This retrospective clinical study was aimed to evaluate cumulative survival rate (CSR) of $Br{\aa}nemark$ implants followed for 10 years and to determine risk factors for implant failure. Material and methods: A total of 271 $Br{\aa}nemark$ implants in 83 patients were investigated with several identified risk factors. Life table analysis was undertaken to examine the CSR. Cox regression method was conducted to assess the association between potential risk factors and overall CSR. Results: Thirty implants failed. The 10-year implant CSR was 82.5%. Cox regression analysis demonstrated a significant predictive association between overall CSR and implant length (P<.05). Conclusion: An acceptable long-term result of $Br{\aa}nemark$ implant was achieved and implant length showed a significant association with the CSR.

• Journal of Periodontal and Implant Science
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• 제49권6호
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• pp.382-396
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• 2019

Purpose: The purpose of this study was to elucidate the efficacy and safety of carbonate apatite (CO₃Ap) granules in 2-stage sinus floor augmentation through the radiographic and histomorphometric assessment of bone biopsy specimens. Methods: Two-stage sinus floor augmentation was performed on 13 patients with a total of 17 implants. Radiographic assessment using panoramic radiographs was performed immediately after augmentation and was also performed 2 additional times, at 7±2 months and 18±2 months post-augmentation, respectively. Bone biopsy specimens taken from planned implant placement sites underwent micro-computed tomography, after which histological sections were prepared. Results: Postoperative healing of the sinus floor augmentation was uneventful in all cases. The mean preoperative residual bone height was 3.5±1.3 mm, and this was increased to 13.3±1.7 mm by augmentation with the CO₃Ap granules. The mean height of the augmented site had decreased to 10.7±1.9 mm by 7±2 months after augmentation; however, implants with lengths in the range of 6.5 to 11.5 mm could still be placed. The mean height of the augmented site had decreased to 9.6±1.4 mm by 18±2 months post-augmentation. No implant failure or complications were observed. Few inflammatory cells or foreign body giant cells were observed in the bone biopsy specimens. Although there were individual differences in the amount of new bone detected, new bone was observed to be in direct contact with the CO₃Ap granules in all cases, without an intermediate layer of fibrous tissue. The amounts of bone and residual CO₃Ap were 33.8%±15.1% and 15.3%±11.9%, respectively. Conclusions: In this first demonstration, low-crystalline CO₃Ap granules showed excellent biocompatibility, and bone biopsy showed them to be replaced with bone in humans. CO₃Ap granules are a useful and safe bone substitute for two-stage sinus floor augmentation.

• Journal of Periodontal and Implant Science
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• 제42권6호
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• pp.217-223
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• 2012

Purpose: Several parameters have been described for determining the success or failure of dental implants. The surface properties of transgingival implant components have had a great impact on the long-term success of dental implants. The purpose of this study was to compare the tendency of two periodontal pathogens to adhere to and colonize zirconia abutments and titanium alloys both in hard surfaces and soft tissues. Methods: Twelve patients participated in this study. Three months after implant placement, the abutments were connected. Five weeks following the abutment connections, the abutments were removed, probing depth measurements were recorded, and gingival biopsies were performed. The abutments and gingival biopsies taken from the buccal gingiva were analyzed using real-time polymerase chain reaction to compare the DNA copy numbers of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and total bacteria. The surface free energy of the abutments was calculated using the sessile water drop method before replacement. Data analyses used the Mann Whitney U-test, and P-values below 0.05 find statistical significance. Results: The present study showed no statistically significant differences between the DNA copy numbers of A. actinomycetemcomitans, P. gingivalis, and total bacteria for both the titanium and zirconia abutments and the biopsies taken from their buccal gingiva. The differences between the free surface energy of the abutments had no influence on the microbiological findings. Conclusions: Zirconia surfaces have comparable properties to titanium alloy surfaces and may be suitable and safe materials for the long-term success of dental implants.

• 구강회복응용과학지
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• 제28권1호
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• pp.1-13
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• 2012

짧은 임플란트는 상악동이나 하치조신경 등의 해부학적 구조물이 있거나 심한 치조골 흡수로 인해 제한적인 치조제 높이를 가지는 부위에서 사용되고 있다. 본 연구는 길이 10 mm 이하의 임플란트에서 임플란트의 길이, 직경, 식립 부위, 골이식술 유무, 보철물의 연결고정 유무가 임플란트의 생존율과 변연골 흡수에 미치는 영향을 알아보고자 하였다. 원광대학교 치과병원 임플란트센터에서 길이 10 mm 이하의 임플란트를 식립한 137명의 환자, 227개 임플란트를 대상으로 진료 기록부를 통해 임플란트의 길이, 직경, 식립 위치, 골이식 유무, 보철물의 연결고정 유무를 조사하였다. 변연골 흡수량은 Emago advanced v5.6(Oral diagnostic systems, Amsterdam, The Netherlands) 프로그램을 이용하여 측정하였다. 총 227개의 임플란트 중 8개가 실패하여, 전체 짧은 임플란트의 생존율은 96.5 %로 나타났다. 골이식 부위와 상악에 식립된 경우 더 높은 실패율을 보이는 경향이 있었으며, 임플란트의 길이와 직경은 변연골 흡수량에 영향을 미치지 않았다. 실패 요인을 조사하였을 때, 상악의 불량한 골질과 골이식 유무가 임플란트의 더 높은 실패율에 영향을 미쳤다. 10 mm 이하 임플란트에서 길이, 직경, 식립 부위, 골이식술과 보철물의 연결 고정은 임플란트 생존율과 변연골 흡수량에 영향을 끼치지 않았다.

• The Journal of Advanced Prosthodontics
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• 제7권6호
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• pp.423-430
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• 2015

PURPOSE. To evaluate the cumulative survival rate (CSR) and mechanical complications of single-tooth $Ankylos^{(R)}$ implants. MATERIALS AND METHODS. This was a retrospective clinical study that analyzed 450 single $Ankylos^{(R)}$ implants installed in 275 patients between December 2005 and December 2012. The main outcomes were survival results CSR and implant failure) and mechanical complications (screw loosening, fracture, and cumulative fracture rate [CFR]). The main outcomes were analyzed according to age, sex, implant length or diameter, bone graft, arch, and position. RESULTS. The 8-year CSR was 96.9%. Thirteen (2.9%) implants failed because of early osseointegration failure in 3, marginal bone loss in 6, and abutment fracture in 4. Screw loosening occurred in 10 implants (2.2%), and 10 abutment fractures occurred. All abutment fractures were located in the neck, and concurrent screw fractures were observed. The CSR and rate of screw loosening did not differ significantly according to factors. The CFR was higher in middle-aged patients (5.3% vs 0.0% in younger and older patients); for teeth in a molar position (5.8% vs 0.0% for premolar or 1.1% for anterior position); and for larger-diameter implants (4.5% for 4.5 mm and 6.7% for 5.5 mm diameter vs 0.5% for 3.5 mm diameter) (all P<.05). CONCLUSION. The $Ankylos^{(R)}$ implant is suitable for single-tooth restoration in Koreans. However, relatively frequent abutment fractures (2.2%) were observed and some fractures resulted in implant failures. Middle-aged patients, the molar position, and a large implant diameter were associated with a high incidence of abutment fracture.

• The Journal of Advanced Prosthodontics
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• 제15권2호
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• pp.63-71
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• 2023

PURPOSE. The aim of this study was to assess the effect of hemispherical dimple structures on the retention of cobalt-chromium (Co-Cr) crowns cemented to titanium abutments, with different heights and numbers of dimples on the axial walls. MATERIALS AND METHODS. 3.0-mm and 6.0-mm abutments (N = 180) and Co-Cr crowns were prepared. The experimental groups were divided into two and four dimple groups. The crowns were cemented by TempBond and PANAVIA F 2.0 cements. The retention forces were measured after thermal treatments. A two-way Analysis of Variance (ANOVA) and post-hoc Tukey HSD test were conducted to analyze change in retention forces by use of dimples between groups, as well as t test for the effect of abutment height change (α = .05). RESULTS. Results of the two-way ANOVA showed a statistically significant difference in retention force due to the use of dimples, regardless of the types of cements used (P < .001). A significantly higher mean retention forces were observed in the groups with dimples than in the control group, using the post hoc Tukey HSD test (P < .001). Results of t test displayed a statistically significant increase in the retention force with 6.0-mm abutments compared with 3.0-mm abutments (P < .001). The groups without dimples revealed adhesive failure of cements, while the groups with dimples showed mixed failure of cements. CONCLUSION. Use of hemispherical dimples was effective for increasing retention forces of cemented crowns.

• Journal of Periodontal and Implant Science
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• 제39권sup2호
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• pp.205-212
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• 2009

Purpose: The aim of this retrospective study was to compare the survival rate of oxidized titanium implants and sandblasted large-grit acid etched implants in soft bone. Methods: 201 oxidized titanium implants were inserted in 84 patients between May 1999 and May 2004. 120 sandblasted large-grit acid etched implants were inserted in 74 patients between December 2000 and May 2004. The patients were followed-up 0${\sim}$5 years in ITI group or 0${\sim}$6 years in BRA group, respectively. The following information was collected from the patient records: age, gender, systemic disease, implant type, number, length and diameter of the implants, their location in the jaws, bone quantity, the number of failed implants, the causes of failure, and advanced surgery for bone augmentation. Results: In the oxidized titanium implants, 8 implants showed early failure, and 1 implant showed late failure, respectively. The cumulative survival rate was 95.48%. In the sandblasted large-grit acid etched implants, 1 implant showed late failure and cumulative survival rate was 99.10%. The cumulative survival rate and the survival rates in the case of the advanced procedure during the implant placement were not significantly different in both groups. Conclusions: Oxidized titanium implants and sandblasted large-grit acid etched implants can be used successfully in soft bone regardless of the surgical methods used during the implant placement. (J Korean Acad Periodontol 2009;39:205-212)

• Journal of Periodontal and Implant Science
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• 제40권2호
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• pp.90-95
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• 2010

Purpose: The aim of this study is to report a case of oral bisphosphonate-related osteonecrosis of the jaw (BRONJ) resulting in implant failure. Methods: A patient suspected of having BRONJ was referred to the Department of Periodontology, Kyung Hee University School of Dentistry for the evaluation and treatment of exposed bone around implants. Results: The patient, who had been taking oral bisphosphonates (BPs) for about a year, was successfully treated with systemic antibiotics, chlorhexidine mouth rinse, explantation, and surgical debridement of necrotic bone. Conclusions: The results of this case suggest that a patient taking BPs orally should be treated cautiously. Appropriate management including cessation of BPs and respective dental treatment may reduce the development of BRONJ.