• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권4호
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• pp.199-206
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• 2019

Objectives: In mandibular edentulism, the treatment option with a two-interforaminal implant-retained bridge and a removable partial denture is rarely evaluated in literature. The aim of this in vitro study was to evaluate the stress distribution of this treatment option by comparing it with traditional treatment options with interforaminal implants in the edentulous mandible. Materials and Methods: Two interforaminal implants were placed in a formalin-fixed cadaver mandible, and overdentures with three different types of attachments were fabricated: (1) two ball attachments and an overdenture, (2) a Dolder bar and an overdenture, and (3) screw-retained two-implant inter-canine porcelain fused to a metal bridge and an implant-assisted removable denture (IARD) with precision attachments. Three biting conditions were generated for each denture type, and the strains were documented under vertical loading of 100 N. Results: The calculated strain values from measured strains in all measurement sites and loading conditions for the screw-retained two-implant intercanine porcelain fused to a metal bridge and a cast framework partial denture with precision attachments situation were lower than in the other scenarios (P<0.05). Conclusion: Within the limitations of the present study, it can be concluded that an IARD may be a reasonable and valuable alternative to ball attachments or a bar in two interforaminal implants, especially when the patients prefer to be able to show their teeth even when they take out their removable dentures.

• 대한치과보철학회지
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• 제57권2호
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• pp.171-175
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• 2019

치조제가 심하게 흡수된 하악의 정확한 해부학적 구조를 채득하는 것은 매우 어렵다. 이 경우 보다 정확한 인상을 채득하기 위하여 수정모형 제작법을 통한 기능 인상 채득이 추천된다. 이를 위해서는 양측에 2개의 임플란트 크라운을 이용하여 적절한 고정원을 얻을 필요가 있다. 이를 통해 임플란트 피개의치에서는 불가능하였던 수정모형 제작법을 시행할 수 있다. 본 증례에서는 하악의 치조제가 심하게 흡수된 80세 여환을 하악 양측 견치 부위의 임플란트 크라운을 지대치로 한 가철성 국소의치를 이용하여 수복하였다. 가철성 국소의치의 금속구조물을 이용하여 개인 트레이를 제작하고 수정모형 제작을 위한 이차 인상을 채득하였다. 환자는 앞선 2회의 피개의치 실패 후 제작된 최종 보철물에 만족하였다. 치료 초기에 행해진 피개의치 치료에서는 부정확한 인상법에 따른 부적절한 보철물로 인해 술자와 환자 모두 만족하지 못했지만, 2개의 임플란트를 적절한 고정원으로 이용함으로써 성공적인 수복이 가능하였다.

• The Journal of Advanced Prosthodontics
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• 제11권2호
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• pp.88-94
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• 2019

PURPOSE. This study was conducted to investigate patterns of adjacent tooth displacement in the posterior implant with interproximal contact loss (ICL) by 3-D digital superimposition method. MATERIALS AND METHODS. Posterior partially edentulous patients, restored with implant fixed partial prostheses before 2011 and suffered from food impaction of ICL between 2009 and 2011, were included. Two dental casts, at the time of delivery and at the time of food impaction in a same patient, was converted into 3-D digital models through scanning and superimposition was performed to assess chronologic changes of the dentition. Directions of tooth displacement were evaluated and the amount of ICL was calculated. Correlations between the amount of ICL and elapsed time, or between the amount of ICL and age after function, were assessed at a significance level of P<.05. RESULTS. A total number of 13 patients (8 males, 5 females) with a mean age of $65.76{\pm}9.94years$ and 17 areas (4 maxillae, 13 mandibles) were included in this retrospective study. Teeth adjacent to the implant restoration showed complex displacements but characteristic tendency according to the location of the arch. The mean amount of ICL was $0.33{\pm}0.14mm$. Elapsed time from function to ICL was $61.47{\pm}31.27months$. There were no significant differences between the amount of ICL and elapsed time, or age (P>.05). CONCLUSION. Natural teeth showed various directional movements to result in occlusal change in the arch. The 3-D superimposition of chronologic digital models was a helpful method to analyze the changes of dentition and individual tooth displacement adjacent to implant restoration.

• Journal of Periodontal and Implant Science
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• 제49권1호
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• pp.25-38
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• 2019

Purpose: This study evaluated differences in bone healing and remodeling among 3 implants with different surfaces: sandblasting and large-grit acid etching (SLA; IS-III $Active^{(R)}$), SLA with hydroxyapatite nanocoating (IS-III $Bioactive^{(R)}$), and SLA stored in sodium chloride solution ($SLActive^{(R)}$). Methods: The mandibular second, third, and fourth premolars of 9 dogs were extracted. After 4 weeks, 9 dogs with edentulous alveolar ridges underwent surgical placement of 3 implants bilaterally and were allowed to heal for 2, 4, or 12 weeks. Histologic and histomorphometric analyses were performed on 54 stained slides based on the following parameters: vertical marginal bone loss at the buccal and lingual aspects of the implant (b-MBL and l-MBL, respectively), mineralized bone-to-implant contact (mBIC), osteoid-to-implant contact (OIC), total bone-to-implant contact (tBIC), mineralized bone area fraction occupied (mBAFO), osteoid area fraction occupied (OAFO), and total bone area fraction occupied (tBAFO) in the threads of the region of interest. Two-way analysis of variance (3 types of implant $surface{\times}3$ healing time periods) and additional analyses for simple effects were performed. Results: Statistically significant differences were observed across the implant surfaces for OIC, mBIC, tBIC, OAFO, and tBAFO. Statistically significant differences were observed over time for l-MBL, mBIC, tBIC, mBAFO, and tBAFO. In addition, an interaction effect between the implant surface and the healing time period was observed for mBIC, tBIC, and mBAFO. Conclusions: Our results suggest that implant surface wettability facilitates bone healing dynamics, which could be attributed to the improvement of early osseointegration. In addition, osteoblasts might become more activated with the use of HA-coated surface implants than with hydrophobic surface implants in the remodeling phase.

• The Journal of Advanced Prosthodontics
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• 제13권2호
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• pp.107-116
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• 2021

PURPOSE. Several studies focused on the accuracy of intra-oral scanners in implant dentistry, but the data of inter-implant distances were not widely mentioned. Therefore, this study aimed to evaluate the effect of distance between two implants on the surface distortion of scanned models generated by intra-oral scanners. MATERIALS AND METHODS. Three models with the distances between two fixed scan bodies of 7, 14, and 21 mm were fabricated and scanned with a highly precise D900L dental laboratory scanner as reference models. Fifteen scans were performed with TRIOS3 and CEREC Omnicam intra-oral scanners. Trueness, precision, and angle deviation of the test models were analyzed (α=.05). RESULTS. There was a significant difference among inter-implant distances in both intraoral scanners (P<.001). The error of trueness and precision increased with the increasing inter-implant length, while the angle deviation did not show the same trend. A significant difference in the angle deviation was found among the inter-implant distance. The greatest angle deviation was reported in the 14-mm group of both scanners (P<.05). In contrast, the lowest angle deviation in the 21-mm group of the TR scanner and the 7-mm of the CR scanner was reported (P<.001). CONCLUSION. The inter-implant distance affected the accuracy of intra-oral scanner. The error of trueness and precision increased along with the increasing distance between two implants. However, the distortions were not clinically significant. Regarding angle deviation, the clinically significant angle deviation may be possible when using intra-oral scanners in the partially edentulous arch.

• 대한치과보철학회지
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• 제59권1호
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• pp.63-70
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• 2021

CAD-CAM 기술의 사용은 다양한 부분에서 치료의 결과를 향상시킨다. 본 증례는 법랑질형 성부전증 환자를 디지털 기술을 이용해 치료한 전악구강회복 증례이다. 임상적 검사 결과 occlusal stop의 부재로 저작기능의 저하와 치아 상실, 왜소치로 인한 치간사이 공간, 불충분한 수직피개 등의 문제점이 파악되었다. 하악의 치아 상실 부위를 수복키 위해 CAD-CAM 수술 스텐트를 이용한 임플란트 식립이 진행되었고 추가적으로 부족한 골량을 보강하기 위해 골유도재생술이 동반되었다. 상하악 자연치는 모두 전장관수복을 통해 새로운 교합평면 설정 및 안정적인 수직교합관계를 형성하였다. ARCUS digma 장비를 통한 잠정수복물 평가 후 디지털 기술을 이용하여 잠정수복물 상태의 수복물을 더블스캔을 통한 복제를 하여 최종수복물을 제작, 환자에게 수복하여 전악수복을 완성하였다. 이를 통해 치료의 효율성과 예지성 있는 결과, 환자의 적응기간 감소와 기능적, 심미적으로 높은 만족도 등을 이루어냈다.

• The Journal of Advanced Prosthodontics
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• 제13권1호
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• pp.46-54
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• 2021

Purpose. The design of the implant-abutment complex is thought to be responsible for marginal bone loss (MBL) and might affect the condition of the peri-implant tissues. This the present study aimed to evaluate the influence of the implant-abutment complex on MBL and the peri-implant tissues in partially edentulous patients treated with dental implants and determine the most advantageous design. Materials and Methods. A total of ninety-one endosseous implants with different designs of implant-abutment complex [tissue level-TL (n = 30), platform switch-PS (n = 18), and platform match-PM (n = 43)] were reviewed for MBL, Probing Pocket Depth (PPD) and Bleeding on Probing (BoP). MBL was calculated for first year of the insertion and the following years. Results. The median MBL for the PM implants (2.66 ± 1.67 mm; n = 43) in the first year was significantly higher than those for the other types (P=.033). The lowest rate of MBL (0.61 ± 0.44 mm; n = 18) was observed with PS implants (P=.000). The position of the crown-abutment border showed a statistically significant influence (P=.019) and a negative correlation (r=-0.395) on MBL. BoP was found significantly higher in PM implants (P=.006). The lowest BoP scores were detected in PS implants, but the difference was not significant (P=.523). The relation between PPD and connection type revealed no statistically significant influence (P>.05). Conclusion. Within the limitations of the present study, it may be concluded that PS implants seem to show better peri-implant soft tissue conditions and cause less MBL.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권1호
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• pp.34-39
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• 2021

Objectives: The purpose of the study was to assess the occurrence, location, and dimensions of the intraosseous vascular canal in the lateral wall of the maxillary antrum using cone-beam computed tomography (CBCT). Materials and Methods: In this retrospective study, we examined 400 CBCT scans from our archive of patients who had earlier reported to a dental teaching hospital in the United Arab Emirates. The prevalence, location, and dimensions of the lateral antral intraosseous canal (LAIC) in the maxillary antrum were evaluated by 2 examiners using standardised methods. A third examiner was consulted in cases of disagreement. Results: The prevalence of LAIC was 62.3% (249 maxillary antra) among the study population. The mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC in the posterior maxillary region was 19.83±3.12 mm. There was a significant difference (P=0.05) between the maxillary molar and premolar regions in mean distance from the most inferior point of the alveolar bone and the inferior border of the LAIC. There was no statistically significant difference in mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC between dentulous and edentulous areas (P=0.1). The G3-intrasinusal type canal less than 1mm in diameter was the most common type of LAIC. Conclusion: This study established the approximate location of the LAIC in a United Arab Emirates cohort, which will assist the oral surgeon in selecting the appropriate site for sinus lift procedures with reduced risk of surgical hemorrhage.

• 구강회복응용과학지
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• 제38권2호
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• pp.110-119
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• 2022

부분 무치악 환자의 가철성 국소의치 수복 시 지대치가 항상 유리한 위치에 존재하지는 않는다. 이로 인하여 잘 맞게 제작된 가철성 국소의치임에도 불구하고 환자는 가철성 국소의치의 안정과 지지에 대하여 만족하지 못하는 경우가 발생하게 된다. 이 때, 소수의 임플란트 크라운을 이용한 가철성 국소의치가 부분 무치악 환자에게 좋은 대안이 될 수 있다. 소수의 임플란트를 위치시키고 지대치로 이용하여 가철성 국소의치의 안정과 지지를 증가시킬 수 있다. 본 증례는 하악 편측에 잔존치를 갖는 환자에서 두개의 임플란트를 전략적으로 위치시켜 지대치를 양측으로 분포시켰다. 최종 가철성 국소의치 수복 이후 환자는 저작 기능에 만족감을 보였으며 국소의치 사용시 편안함을 나타내었다.

• 대한치과보철학회지
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• 제60권3호
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• pp.254-262
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• 2022

편악 부분 무치악 환자를 치료하는 경우, 적절한 수복 재료를 사용하는 것이 중요하다. 적절하지 않은 수복 재료는 보철 수복의 결과에 좋지 않은 영향을 줄 수 있다. 현재 널리 사용되고 있는 재료들인 지르코니아와 치과용 합금은 피질골보다 탄성 계수가 높아 외력 발생시 임플란트 및 임플란트 주위 골에 유해한 힘을 가할 수 있다. 최근 새롭게 소개된 재료인 Polyetherketoneketone (PEKK)은 피질골과 유사한 탄성계수를 가졌으며, 물리적 특성 및 생체 친화성에 있어서도 많은 이점을 가지고 있다. 본 증례에서는 PEKK를 이용한 임플란트 지지형 고정성 보철치료를 진행하였고 기능적, 심미적으로 만족할 만한 결과를 얻었기에 이를 보고하는 바이다.