• 대한치과의사협회지
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• 제24권4호통권203호
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• pp.367-373
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• 1986

• Journal of Periodontal and Implant Science
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• 제29권4호
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• pp.943-953
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• 1999

Severe alveolar ridge deficiency can prevent ideal implant placement. Ridge augmentation procedures are necessary to regain lost alveolar structures. The corticocancellous block bone graft was harvested from the mandibular symphysis. This block bone was fixed to the lateral aspect of the ridge with titanium screws. Seven months later, the autogenous bone graft was reentered and sufficient bone volume was gained to allow implant placement. The fixation screws were removed and 3I implants were inserted. No complication and postoperative alteration in chin contour were observed. This report demonstrates that chin graft offers a predictable alternative in the reconstruction of ridge deficiency for implant placement.

• 대한치과보철학회지
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• 제45권3호
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• pp.321-328
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• 2007

Statement of problem. To work the economic limitation of dental implant usage, some types of domestic implant have been developing. But, there have been seldom reported about the clinical success rate of them as yet. Purpose. The aim of this retrospective multicenter study was to evaluate the performance of CSM implants(CSM company, Daegu, Korea). Material and methods. Thirty-five patients were rehabilitated with 150 CSM implants in this multicenter study. Results. The success rate was 96.2%. CSM Titanium fixtures can obtain slightly higher success rate when a cover screw was not used for implant installation than when used. However it doesn't show significant difference(p=.7615, Fisher's Exact test). Conclusion. This multicenter retrospective study demonstrated the efficacy of the CSM implant in the treatment of variety of clinical manifestation of tooth loss. And it can be assumed that whether a cover screw is used or not should no influence on the osseointegration.

• The Journal of Advanced Prosthodontics
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• 제14권6호
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• pp.346-359
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• 2022

PURPOSE. Four and six implant-supported fixed full-arch prostheses with various framework materials were assessed under different loading conditions. MATERIALS AND METHODS. In the edentulous maxilla, the implants were positioned in a configuration of four to six implant modalities. CoCr, Ti, ZrO₂, and PEEK materials were used to produce the prosthetic structure. Using finite element stress analysis, the first molar was subjected to a 200 N axial and 45° oblique force. Stresses were measured on the bone, implants, abutment screw, abutment, and prosthetic screw. The Von Mises, maximum, and minimum principal stress values were calculated and compared. RESULTS. The maximum and minimum principal stresses in bone were determined as CoCr < ZrO₂ < Ti < PEEK. The Von Mises stresses on the implant, implant screw, abutment, and prosthetic screws were determined as CoCr < ZrO₂ < Ti < PEEK. The highest Von Mises stress was 9584.4 Mpa in PEEK material on the prosthetic screw under 4 implant-oblique loading. The highest maximum principal stress value in bone was found to be 120.89 Mpa, for PEEK in 4 implant-oblique loading. CONCLUSION. For four and six implant-supported structures, and depending on the loading condition, the system accumulated different stresses. The distribution of stress was reduced in materials with a high elastic modulus. When choosing materials for implant-supported fixed prostheses, it is essential to consider both the number of implants and the mechanical and physical attributes of the framework material.

• Journal of Periodontal and Implant Science
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• 제41권6호
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• pp.263-272
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• 2011

A number of surface modification techniques using immobilization of biofunctional molecules of Titanium (Ti) for dental implants as well as surface properties of Ti and Ti alloys have been developed. The method using passive surface oxide film on titanium takes advantage of the fact that the surface film on Ti consists mainly of amorphous or low-crystalline and nonstoichiometric $TiO_2$. In another method, the reconstruction of passive films, calcium phosphate naturally forms on Ti and its alloys, which is characteristic of Ti. A third method uses the surface active hydroxyl group. The oxide surface immediately reacts with water molecules and hydroxyl groups are formed. The hydroxyl groups dissociate in aqueous solutions and show acidic and basic properties. Several additional methods are also possible, including surface modification techniques, immobilization of poly(ethylene glycol), and immobilization of biomolecules such as bone morphogenetic protein, peptide, collagen, hydrogel, and gelatin.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권4호
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• pp.204-211
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• 2012

Objectives: Dental implants installation in patients with diabetes remains controversial as altered bone healing around implants has been reported. And little is known about the biological factors involved in bone healing around implants. The present study aimed to investigate the biological markers around immediately placed implants in rats with controlled and uncontrolled diabetes. Materials and Methods: Twenty rats (40 sites) were divided into the control, insulin-treated and diabetic groups. The rats received streptozotocin (60 mg/kg) to induce diabetes; animals in the insulin-treated group also received three units of subcutaneous slow-release insulin. Two threaded titanium alloy implant ($1.2{\times}3mm$) were placed in the extraction socket of the both maxillary first molars and allowed for healing. Bone blocks including implant were harvested at 3 days, 1, 2 and 4 weeks. The levels of bone morphogenetic protein (BMP)-4, transforming growth factor (TGF)-${\beta}1$, osteocalcin (OC) and osteonectin (ON) were measured in the peri-implant osseous samples by RT-PCR. Results: The BMP-4 level increased immediately in all groups by day 3, then decreased abruptly in the control and the insulin-treated groups. However, by week 4, all groups showed mostly the same amount of BMP-4 expression. The level of TGF-${\beta}1$ also instantly increased by day 3 in the insulin-treated group. This level elevated again reaching the same values as the control group by week 4, but was not as high as the diabetic group. In addition, the expression of OC and ON in the control and insulin-treated groups was higher than that of the diabetic group at 2 weeks and 4 weeks, indicating active bone formation in these groups. Conclusion: The immediate placement of titanium implants in the maxilla of diabetic rat led to an unwanted bone healing response. Conclusively, the results of this study suggest that immediate implant insertion in patients with poorly controlled diabetes might be contraindicated.

• 대한치과보철학회지
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• 제47권1호
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• pp.12-20
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• 2009

연구목적: 임플란트가 식립되어질 때 매식체는 조직액과 접촉하게 된다. 임플란트의 조직액 흡착은 표면처리에 따라 다양하게 나타난다. 이 때 임플란트 시편의 표면 거칠기와 젖음성과의 상관관계를 분석하고자 하였다. 연구재료 및 방법: 표면 거칠기와 젖음성의 상관관계를 측정하기 위해 네 종류의 임플란트 시편을 각각 5종류 만들었다. 각각의 그룹은 그룹 A: Machined Surface, 그룹 B: Anodized surface, 그룹 C: RBM (HA blasting) surface, 그룹 D: CMP (calcium methaphosphate) coating surface이다. 연구결과: 1. 표면의 거칠기는 RBM, CMP, Anodized, Machined 그룹 순서로 거칠었다. RBM과 CMP는 통계적으로 유의차가 없었다 (P<.05). 2. 젖음성은 Anodized, RBM, CMP, Machined 그룹 순서로 높았다. CMP와 Machined는 통계적으로 유의차가 없었다 (P<.05). 3. 표면 거칠기와 젖음성과의 상관관계는 없었다.

• Journal of Periodontal and Implant Science
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• 제36권3호
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• pp.705-716
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• 2006

The present study was performed to evaluate the effect of tetracycline-HCl on the change of implant surface microstructure according to application time. Implant with pure titanium machined surface, GBA surface and RBM surface were utilized. Implant surface was rubbed with 50mg/ml tetracycline-HCl solution for ${\frac{1}{2}}$min. 1min. $1{\frac{1}{2}}$min. 2min. and $2{\frac{1}{2}}$min. respectively in the test group. Then, specimens were processed for scanning electron microscopic observation. The results of this study were as follow. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two group. 2. In GBA surfaces, control group exhibit many porous depression, and each depression were divided by strict border. Experimental group applied with tetracycline-HCl for 2min. were similar with control group. But when applied for $2{\frac{1}{2}}$min. surface alteration and border breakdown started, resulting enlargement of the porous depression. 3. In REM surface, control group exhibit rough, uneven surface with crater-like depression can be found. The surface alteration started when tetracycline-HCl was applied for 30sec. resulting breakdown of the crater-like depression. Depression became larger as applying time increased.

• 대한치과보철학회지
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• 제57권1호
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• pp.88-94
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• 2019

심미적 치료에 대한 요구가 늘어나면서 높은 강도와 심미성을 갖는 지르코니아의 요구도 증가하고 있다. 이러한 흐름에 비추어 지르코니아의 생체적 합성을 평가하는 것은 중요한 일이다. 이번 논문에서는 지르코니아의 생체적합성에 대한 in vivo 실험에 대한 문헌 연구를 진행하였다. In vivo 실험에서 연조직, 경조직에 대한 지르코니아의 생체적합성을 확인할 수 있었다. 다양한 실험동물 및 환자에서 진행된 연구의 대다수에서 지르코니아의 높은 생체적합성이 보고되었으며, 신생골 합성 및 골부착의 면에서 티타늄과 유사한 성질을 보였다. 한편, 지르코니아는 임플란트로도 활용할 수 있다. 임플란트로 활용하기 위해 HA (hydroxyapatite)를 처리하여 생체활성을 높이는 다양한 방식이 제안되고 있다. 하지만 기존의 티타늄 임플란트에 HA를 코팅하는 방식은 낮은 결합강도 및 HA의 변성으로 인한 문제점이 있었기 때문에 HA-지르코니아 composite, HA-coated 지르코니아, HA-지르코니아 functionally graded material (FGM) 또는 알루미나 개재 HA-지르코니아 등의 새로운 방식이 연구되고 있다. 이러한 방식들은 보다 높은 결합강도를 지니고 있으며, 높은 생체적합성을 보여주고 있다.

• The Journal of Advanced Prosthodontics
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• 제16권4호
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• pp.231-243
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• 2024

PURPOSE. The objective of the study was to analyze the impact of cement, bonding pretreatment, and ceramic abutment material on the overall color results of CAD-CAM ceramic crowns bonded to titanium-based hybrid abutments. MATERIALS AND METHODS. For single implant restoration of a maxillary lateral incisor a total of 51 CAD-CAM-fabricated monolithic lithium disilicate crowns were fabricated and subsequently bonded onto 24 lithium disilicate Ti-base abutments, 24 zirconia Ti-base abutments and 3 resin abutment replicas as a control group. The 48 copings were cemented with three definitive and one provisional cement on both grit-blasted and non-blasted Ti-bases. The color of each restoration and surrounding artificial gingiva was measured spectrophotometrically at predefined measuring points and the CIELAB (ΔE_ab) color scale values were recorded. RESULTS. The color outcome of ceramic crowns bonded to hybrid abutments and soft tissues was affected differently by cements of different brands. Grit-blasting of Ti-bases prior to cementing CAD-CAM copings affected the color results of allceramic crowns. There was a significant difference (P = .038) for the median ΔE value between blasted and non-blasted reconstructions at the cervical aspect of the crown. Full-ceramic crowns on zirconia Ti-base abutments exhibited significantly lower ΔE values below the threshold of visibility (ΔE 1.8). In all subcategories tested, the use of a highly opaque temporary cement demonstrated the lowest median ΔE for both the crown and the artificial gingiva. CONCLUSION. Various cements, core ceramic materials and airborne particle abrasion prior to bonding can adversely affect the color of Ti-base supported ceramic crowns and peri-implant soft tissue. However, zirconia CAD-CAM copings and an opaque cement can effectively mask this darkening.