• 대한치과의사협회지
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• 제32권1호통권296호
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• pp.62-68
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• 1994

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.255-255
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• 2012

The interactions between cells and nanotopographies are increasingly interested as nanotopographies that may be more efficient in promoting cell functions and, titanium nanotubes have attracted much attention. Titanium nanotube can be fabricated easily with precisely controlled diameters and lengths. Titanium nanotubes with the suitable tube dimensions have been observed to enhance bone cell functions, whereas, there is still some controversy. These nanotubes can also serve as carriers for drugs such as growth factors, antibacterial agents and other drugs and show promise in bone implant applications.

• 대한치과보철학회지
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• 제33권2호
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• pp.317-334
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• 1995

The purpose of this study was to compare the bone formation, maturation around HA-and titaniumcoated dental implants in dog. 5 hydroxyapatite coated IMZ implants and 5 titanium coated IMZ implants were placed into the previously extracted site in the mandible of 5 adults dogs. All dogs were injected intravenously Tetracycline, Alizalin red S, and Calcein for bone fluorescent labelling, After the experimental period of 16weeks, the dogs were sacrificed and tissue samples around the implants were obtained. Microscopic observations(ligth, polariged and fluorescence microscope), morphometric analysis, line profile with EPMA, and quantitative analysis for Ca,P, and Ti were performed. The results were as follows ; 1. Bone maturations around the implants were relatively lower than those of natural teeth. No significant differences in bone maturation and remodeling patterns were observed between the two implants groups. 2. Calcification of bone surrounding the implants was initiated in 8-11 weeks for HA-coated implants, while it took 11 weeks or more for Ti-coated implants. 3. Bone-to-implants contact ratio of 82.63% was recorded for HA-coated group and 72.25% for titanium coated group, with no significant difference between the two groups. 4. Bone around the implants exhibited reduced quantity of Ca and P in the $100{\mu}m$ region relative to natural teeth, while the rest of the regions showed no statistical differences. No significant differences were found between the two implant groups. 5. There was a separation of HA layer from the implant core and subsequent infiltration of inflammatory cells into the resulting space in the HA-coated implants, and evidences of phagocytosis of HA particles by macrophages. Bone calcification was more rapid around HA-coated implants compared to titanium-coated implants, but HA coated implants did not show any significant differences either in the degree of calcification or the bone-to-implant contact ratio over Ti coated implants. HA coated implants may have complications associated with HA absorption and separation of HA layer from the implant core.

• Journal of Periodontal and Implant Science
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• 제32권3호
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• pp.615-630
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• 2002

Various long-term studies have shown that titanium implants as abutments for different types of prostheses have become a predictable adjunct in the treatment of partially or fully edentulous patients. The continuous exposure of dental implants to the oral cavity with all its possible contaminants creates a problem. A lack of attachment, together with or caused by bacterial insult, may lead to peri-implantitis and eventual implant failure. Removal of plaque and calculus deposits from dental titanium implants with procedures and instruments originally made for cleaning natural teeth or roots may cause major alterations of the delicate titanium oxide layer. Therefore, the ultimate goal of a cleaning procedure should be to remove the contaminants and restore the elemental composition of the surface oxide without changing the surface topography and harming the surrounding tissues. Among many chemical and mechanical procedure, air-powder abrasive have been known to be most effective for cleaning and detoxification of implant surface. Most of published studies show that the dental laser may be useful in the treatment of pen-implantitis. $CO_2$ laser and Soft Diode laser were reported to kill bacteria of implant surface. The purpose of this study was to obtain clinical guide by application these laser to implant surface by means of Non-contact Surface profilometer and X-ray photoelectron spectroscopy(XPS) with respect to surface roughness and atomic composition. Experimental rough pure titanium cylinder models were fabricated. All of them was air-powder abraded for 1 minute and they were named control group. And then, the $CO_2$ laser treatment under dry, hydrogen peroxide and wet condition or the Soft Diode laser treatment under Toluidine blue O solution condition was performed on the each of the control models. The results were as follows: 1. Mean Surface roughness(Ra) of all experimental group was decreased than that of control group. But it wasn't statistically significant. 2. XPS analysis showed that in the all experimental group, titanium level were decreased, when compared with control group. 3. XPS analysis showed that the level of oxygen in the experimental group 1, 3($CO_2$ laser treatment under dry and wet condition) and 4(Soft Diode laser was used under toluidine blue O solution) were decreased, when compared with control group. 4. XPS analysis showed that the atomic composition of experimental group 2($CO_2$ laser treatment under hydrogen peroxide) was to be closest to that of control group than the other experimental group. From the result of this study, this may be concluded. Following air-powder abrasive treatment, the $CO_2$ laser in safe d-pulse mode and the Soft Diode laser used with photosensitizer would not change rough titanium surface roughness. Especially, $CO_2$ laser treatment under hydrogen peroxide gave the best results from elemental points of view, and can be used safely to treat peri-implantitis.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.115-116
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• 2012

In this study, fitness and fatigue test were performed to estimate the coating effects of abutment screw for implant system after fatigue test. The purpose of this study was to investigate fatigue fracture phenomena of dental implant fixture used titanium nitride coated abutment screw under cyclic load.

• 대한치과보철학회지
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• 제41권4호
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• pp.503-518
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• 2003

Statement of problem : There have been previous studies about considerable variations in machining accuracy and consistency in the implant-abutment-screw interfaces. Purpose : The purpose of this study was to evaluate the machining accuracy and consistency of implant/abutment/screw combinations on two randomly selected implants from each of four manufactures. Material and methods : In this study, screws were respectively used to secure a cemented abutment, to a hexlock implant fixture ; teflon coated titanium alloy screw(Torq-Tite) and titanium alloy screw in Steri--Oss system, gold-plated gold-palladium alloy screw(Gold-Tite) and titanium alloy screw in 3i system gild screw ana titanium screw in AVANA Dental Implant system, and titanium screws in Paragon System. The implants were perpendicularly mounted in polymethyl methacrylate autopolymerizing acrylic resin block(Orthodontic resin, Densply International Inc. USA) by use of dental surveyer. Each abutment screw was secured to the implant with recommended torque value using a digital torque controller. Each screw was again tightened after 10 minutes. All samples were cross sectioned with grinder-polisher unit(Omnilap 2000 SBT Inc) after embeded in liquid unsaturated polyester (Epovia, Cray Valley Inc) Results : There were the largest gaps in the neck areas of screws in hexagonal extension implants which were examined in this study. The leading edge of the abutment screw thread (superior surface) was in contact with the implant body thread, and the majority of the contacting surfaces were localized to the middle portion of the mating threads. Considerable variation in the contacting surfaces was noted in the samples evaluated. Amounts of contact in the abutment screw thread were larger for assemblies with Gold-Tite screw, gold alloy screw. Torq-Tite screw than those with titanium screws. The findings of intimate contact between the screw and screw seat were seen in all samples, regardless of manufacturers. However, microgap between the head and lateral neck surface of the screw and the abutment could be dectected in all samples. The findings of intimate contact between the platform of the implant and the bottom of the abutment were consistent in all samples, regardless of manufacturers. However, microgaps between the lateral surface of external hex of the fixture and the abutment could be dectected in all samples. Conclusion : Considerable variations in machining accuracy and consistency were noted in the samples and the implant-abutment-screw interfaces were incomplete. From the results of this study, further development of the system will be required, including improvements in pattern design.

• Imaging Science in Dentistry
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• 제51권1호
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• pp.1-7
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• 2021

Purpose: The aim of this study was to assess artifacts generated in cone-beam computed tomography (CBCT) of 3 types of dental implants using 3 metal artifact reduction (MAR) algorithm conditions (pre-acquisition MAR, post-acquisition MAR, and no MAR), and 2 peak kilovoltage (kVp) settings. Materials and Methods: Titanium-zirconium, titanium, and zirconium alloy implants were placed in a dry mandible. CBCT images were acquired using 84 and 90 kVp and at normal resolution for all 3 MAR conditions. The images were analyzed using ImageJ software (National Institutes of Health, Bethesda, MD) to calculate the intensity of artifacts for each combination of material and settings. A 3-factor analysis of variance model with up to 3-way interactions was used to determine whether there was a statistically significant difference in the mean intensity of artifacts associated with each factor. Results: The analysis of all 3 MAR conditions showed that using no MAR resulted in substantially more severe artifacts than either of the 2 MAR algorithms for the 3 implant materials; however, there were no significant differences between pre- and post-acquisition MAR. The 90 kVp setting generated less intense artifacts on average than the 84 kVp setting. The titanium-zirconium alloy generated significantly less intense artifacts than zirconium. Titanium generated artifacts at an intermediate level relative to the other 2 implant materials, but was not statistically significantly different from either. Conclusion: This in vitro study suggests that artifacts can be minimized by using a titanium-zirconium alloy at the 90 kVp setting, with either MAR setting.

• 구강회복응용과학지
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• 제26권3호
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• pp.273-283
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• 2010

이 연구는 다수의 임플란트에 의해 지지되는 보철물과 단일 임플란트 보철물에서 호환 가능한 세 가지 종류의 나사의 풀림토크값을 측정하여 나사 결합부 안정성에 차이가 있는지를 알아보고자 하였다. 이를 위해, 네 개의 외부 육각 임플란트에 직접 연결되는 임플란트 상부구조물을, 아크릴릭 레진을 이용한 연결인상법으로 얻은 총 6개의 실험모형에 20 Ncm의 힘으로 조인 후, 각 나사의 풀림토크값을 총 2회 측정하였다. 사용한 지대주 나사는 토크타이트(TorqTite), 골드타이트(Gold-Tite), 그리고, 티타늄(Titanium) 나사였다. 또한, 단일 임플란트 수복의 경우 를 가정하여 총 5개의 실험모형 상의 2개의 임플란트에, 한 개의 지대주(GoldAdapt Engaging)를 다시 세 종류의 나사로 연결한 후, 각 나사의 풀림토크값을 총 2회 측정하였다. 나사의 풀림토크값의 비교를 위한 통계적 분석을 혼합모형(mixed model)을 이용하여 유의수준 .05에서 실시한 결과, 다수 임플란트 지지 상부구조물의 경우, 나사의 종류에 따른 풀림토크값은 통계적으로 유의성 있는 차이를 보이지 않았다(p>0.05). 그러나 단일 임플란트 지대주의 경우에는 통계적으로 유의성 있는 차이를 보였으며(p=0.0175), 토크타이트 나사(p=0.0462)와 티타늄 나사(p=0.0348)는 각각, 골드타이트 나사보다 유의성 있게 큰 풀림토크값을 보였으나, 두 나사 간에는 유의성 있는 차이가 없었다(p>0.05). 이상의 연구 결과로 보아, 서로 다른 종류의 나사가 나사 결합부의 초기 안정성에 미치는 영향은, 단일 임플란트 보철물의 경우에서와는 달리, 다수의 임플란트에 의해 지지되는 보철물의 경우에는 미미하다고 할 수 있다.

• 대한치과보철학회지
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• 제34권4호
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• pp.800-815
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• 1996

Pulsed Nd : YAG laser has been used to treat various soft tissue lesions. However, there have been warnings of using laser to treat peri-implantitis because the laser can alter the surface of implant and can rise its temperature so that it might be harmful to implant itself and its surrounding tissue. However, the study in vivo has not been done yet. The purpose of this study was to evaluate the biocompatibility to the pulsed Nd:YAG lased dental implant. 16 HA coated implants and 16 titanium plasma sprayed implants were used. They were divided 4 groups as unlased control, 0.3 watt, 1.0 watt and 2.0 watt lased groups after lasing. And they were implanted in the peritonial walls of 12 rabbits. The rabbits were sacrificed 6 weeks after implantation and the LM and EM specimems were made. 1. In the unlased implant group, both HA coated and titanium plasma sprayed implants were surrounded by fibroblasts and collagen fibers. No macrophages and inflammatory cells were seen. 2. In HA coated implants 0.3 watt, 1.0 watt lased group had a little inflammation, but in 2.0 watt lased group had scattered macrophages, a significantly larger number of chronic imflammatory cells were seen. 3. In titanium plasma sprayed implant 0.3 watt, 1.0 watt lased group had a little inflammation, but in 2.0 watt group had severe inflammation as in the conditions of HA coated group. 4. The inflammatory reaction of both lased HA coated and titanium plasma sprayed implant groups increased as the increase of the power of the laser.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권1호
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• pp.30-35
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• 2011

Introduction: Dental implants are used routinely with high success rates in generally healthy individuals. By contrast, their use in patients with diabetes mellitus is controversial because altered bone healing around implants has been reported. This study examined the bone healing response around titanium implants placed immediately in rats with controlled and uncontrolled diabetes. Materials and Methods: Twenty rats 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. A titanium implant ($1.2{\times}3\;mm$) was placed in the extraction socket of the maxillary first molar and bone block was harvested at 1, 2 and 4 weeks. Results: Bone formation around the implants was consistently (from 1 to 4 week post-implantation) slower for the diabetic group than the control and insulin-treated group. Bone morphogenesis in the diabetic rats was characterized by fragmented bone tissues and extensive soft tissue intervention. Conclusion: The immediate placement of titanium implants in the maxilla of diabetic rats led to an unwanted bone healing response. These results suggest that immediate implant insertion in patients with poorly controlled diabetes might be contraindicated.