• The Journal of Advanced Prosthodontics
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• 제5권2호
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• pp.198-203
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• 2013

PURPOSE. The purpose of this study was to investigate the effect of resin cements and primer on the retentive force of zirconia copings bonded to zirconia abutments with insufficient retention. MATERIALS AND METHODS. Zirconia blocks (Lava, 3M ESPE, St. Paul, MN, USA) were obtained and forty sets of zirconia abutments and copings were fabricated using CAD/CAM technology. They were grouped into 4 categories as follows, depending on the types of resin cements used, and whether the primer is applied or not:Panavia F2.0 (P), Panavia F2.0 using Primer (PRIME Plus, Bisco Inc, Schaumburg, IL, USA) (PZ), Superbond C&B (S), and Superbond C&B using Primer (SZ). For each of the groups, the cementation was conducted. The specimens were kept in sterilized water ($37^{\circ}C$) for 24 hours. Retentive forces were tested and measured, and a statistical analysis was carried out. The nature of failure was recorded. RESULTS. The means and standard deviations of retentive force in Newton for each group were $265.15{\pm}35.04$ N (P), $318.21{\pm}22.24$ N (PZ), $445.13{\pm}78.54$ N (S) and $508.21{\pm}79.48$ N (SZ). Superbond C&B groups (S & SZ) showed significantly higher retentive force than Panavia F2.0 groups (P & PZ). In Panavia F2.0 groups, the use of primer was found to contribute to the increase of retentive force. On the other hand, in Superbond C&B groups, the use of primer did not influence the retention forces. Adhesive failure was observed in all groups. CONCLUSION. This study suggests that cementation of the zirconia abutments and zirconia copings with Superbond C&B have a higher retentive force than Panavia F2.0. When using Panavia F2.0, the use of primer increases the retentive force.

• 대한심미치과학회지
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• 제20권1호
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• pp.78-83
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• 2011

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 1999년도 Asian Academy of Prosthodntics. Korean Academy of Prosthodontics
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• pp.76.1-76.1
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• 1999

• The Journal of Advanced Prosthodontics
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• 제8권4호
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• pp.329-332
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• 2016

Fabricating a surveyed prosthesis beneath an existing partial removable dental prosthesis (PRDP) is a challenging and time-consuming procedure. The computer-aided design/computer-assisted manufacturing (CAD/CAM) technology was applied to fabricate a retrofitted, surveyed zirconia prosthesis to an existing PRDP. CAD/CAM technology enabled precise and easy replication of the contour of the planned surveyed crown on the existing abutment tooth. This technology ensured excellent adaptation and fit of newly fabricated crown to the existing PRDP with minimal adjustments. In this case report, a seventy-year-old male patient presented with fractured existing surveyed crown. Because the existing PRDP was serviceable, new crown was fabricated to the existing PRDP.

• 구강회복응용과학지
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• 제28권2호
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• pp.201-212
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• 2012

임플란트 주위조직과 치아 주위조직은 조직학, 형태학적으로 유사한 면이 있다. 특히 functional ankylosis라 불리는 티타늄과 연조직의 직접적인 상피부착은 치아주위 조직의 접합상피처럼 염증세포의 치근단으로의 이행 및 그로 인한 골흡수를 막는 역할을 한다. 그러나 반복적인 지대주의 착탈은 임플란트 주위 연조직의 mucosal barrier를 파괴하여 골흡수를 야기할 수 있다. 만일 지대주의 반복적인 착탈 없이 수술 시에 보철 지대주를 채결한다면 골흡수의 양을 줄일 수 있을 것이다. 이는 기존의 수술방법으로는 한계가 있었으나 Cone Beam Computed Tomography(CBCT)를 이용한 guided surgery를 이용함으로써 임플란트 식립의 3차원적 정확성의 비약적인 향상으로 이런 술식이 가능하게 되었다. 본 증례는 정밀한 CBCT를 통한 분석 후 지르코니아 맞춤 지대주를 미리 제작하고 수술 시에 즉시 지대주와 임시보철물을 연결한 경우로 임상적으로 만족할만한 결과를 얻어 이를 보고하는 바이다.

• 대한치과보철학회지
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• 제52권4호
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• pp.352-358
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• 2014

최근 지르코니아와 CAD/CAM을 이용하는 심미적인 임플란트 보철치료 방법들이 많이 소개되고 있다. 그러나 이러한 방법들은 치은부위와 교합면부위에서 한계점들을 가지고 있다. 이에 본 증례에서는 지르코니아와 CAD/CAM 시스템을 이용하여 고정체 1 mm 상부에서부터 형성되는 점막하지르코니아 임플란트 보철물을 제작하고 이를 타이타늄 지대주와 접착하여 시멘트 나사 유지형 보철물을 제작하였다. 임상적으로 심미적이고 기능적면에서 만족할 만한 결과를 얻었기에 이를 보고하고자 한다.

• 대한치과보철학회지
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• 제55권2호
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• pp.218-224
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• 2017

방사선치료를 받은 상악에 임플란트 지지 고정성 보철물을 이용하여 수복하는 것은 골치유능력이 낮기 때문에 상세한 치료계획이 필요하다. All-on-4 개념에 의한 임플란트 식립은 골이식을 피하면서 임플란트를 매식할 수 있어 유리하다. 일반적으로 경사된 임플란트에는 기성 경사형 지대주를 사용해왔다. 본 임상증례에서는 computer-aided design and computer-aided manufacturing (CAD/CAM)으로 제작된 지대주를 사용하였다. 본 증례는 all-on-4 개념에 의해 임플란트를 매식하고 CAD/CAM titanium 지대주를 제작한 다음 CAD/CAM zirconia 고정성 보철물로 수복하여 좋은 결과를 얻었기에 보고하고자 한다.

• The Journal of Advanced Prosthodontics
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• 제10권5호
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• pp.381-387
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• 2018

PURPOSE. Cement-retained implant prostheses can lack proper retrievability during repair, and residual cement can cause peri-implantitis. The purpose of this in vitro study was to evaluate the influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with lingual slots, known as retrievable cement-type slots (RCS). MATERIALS AND METHODS. We fabricated six types of titanium abutments (10 of each type) with two different heights (4 mm and 6 mm), three different convergence angles ($8^{\circ}$, $10^{\circ}$, and $12^{\circ}$), a sloped shoulder margin (0.6 mm depth), a rectangular shape ($6mm{\times}6.5mm$) with rounded edges, and a rectangular ledge ($2mm{\times}1mm$) for the RCS. One monolithic zirconia crown was fabricated for each abutment using a dental computer-aided design/computer-aided manufacturing system. The abutments and crowns were permanently cemented together with dual-curing resin cement, followed by 24 hours in demineralized water at room temperature. Using a custom-made device with a slot driver and torque gauge, we recorded the torque ($N{\cdot}cm$) required to remove the crowns. Statistical analysis was conducted using multiple regression analysis and Mann-Whitney U tests (${\alpha}=.05$). RESULTS. Removal torques significantly decreased as convergence angles increased. Multiple regression analysis showed no significant interaction between the abutment height and the convergence angle (Durbin-Watson ratio: 2.186). CONCLUSION. Within the limitations of this in vitro study, we suggest that the retrievability of cement-retained implant prostheses with RCS can be maintained by adjusting the abutment height and convergence angle, even when they are permanently cemented together.

• The Journal of Advanced Prosthodontics
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• 제12권4호
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• pp.233-238
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• 2020

PURPOSE. This study aims to compare the marginal fitness of two types of implant-supported fixed dental prosthesis, i.e., cementless fixation (CL.F) system and cement-retained type. MATERIALS AND METHODS. In each group, ten specimens were assessed. Each specimen comprised implant lab analog, titanium abutment fabricated with a 2-degree tapered axial wall, and zirconia crown. The crown of the CL.F system was retained by frictional force between abutment and relined composite resin. In the cement-retained type, zinc oxide eugenol cement was used to set crown and abutment. All specimens were sterilized with ethylene oxide, immersed in Prevotella intermedia culture in a 50 mL tube, and incubated with rotation. After 48 h, the specimens were washed thoroughly before separating the crown and abutment. The bacteria that penetrated into the crown-abutment interface were collected by washing with 500 µL of sterile saline. The bacterial cell number was quantified using the agar plate count technique. The BacTiter-Glo Microbial Cell Viability Assay Kit was used to measure bacterial adenosine triphosphate (ATP)-bioluminescence, which reflects the bacterial viability. The t-test was performed, and the significance level was set at 5%. RESULTS. The number of penetrating bacterial cells assessed by colony-forming units was approximately 33% lower in the CL.F system than in the cement-retained type (P<.05). ATP-bioluminescence was approximately 41% lower in the CL.F system than in the cement-retained type (P<.05). CONCLUSION. The CL.F system is more resistant to bacterial penetration into the abutment-crown interface than the cement-retained type, thereby indicating a precise marginal fit.

• The Journal of Advanced Prosthodontics
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• 제15권1호
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• pp.33-43
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• 2023

PURPOSE. This study investigated the physical and mechanical changes in the titanium base of three different hybrid abutment materials after cyclic loading by estimating the post-load reverse torque value (RTV), compressive side fulcrum wear pattern of titanium base, and surface roughness. MATERIALS AND METHODS. A total of 24 dental implants were divided into three groups (n = 8 each): Group Z, LD, and P used zirconia, lithium disilicate, and polyetheretherketone, respectively, for hybrid abutment fabrication. RTV was evaluated after cyclic loading with 50 N for 1.2 × 10⁶ chewing cycles. The compressive sides of the titanium bases were analyzed using a scanning electron microscope, and the roughness of the affected areas was measured using an optical profilometer after loading. Datasets were analyzed using Kruskal-Wallis test followed by Mann-Whitney tests with the Bonferroni correction (α = .05). RESULTS. Twenty-three samples passed the test; one LD sample fractured after 770,474 cycles. Post-load RTV varied significantly depending on the hybridabutment material (P = .020). Group P had a significantly higher median of post-load RTVs than group Z (16.5 and 14.3 Ncm, respectively). Groups LD and P showed minor signs of wear, and group Z showed a more pronounced wear pattern. While evaluating compressive side affected area roughness of titanium bases, lower medians were shown in group LD (Ra 0.16 and Rq 0.22 ㎛) and group P (Ra 0.16 and Rq 0.23 ㎛) than in group Z (Ra 0.26 and Rq 0.34 ㎛); significant differences were found only among the unaffected surface and group Z. CONCLUSION. The hybrid abutment material influences the post-load RTV. Group Z had a more pronounced wear pattern on the compressive side of titanium base; however, the surface roughness was not statistically different among the hybridabutment groups.