• 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.

• Journal of Korean Dental Science
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• 제12권1호
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• pp.5-12
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• 2019

Purpose: To determine the benefits of autogenous tooth bone (ATB) graft in combination with platelet-rich plasma (PRP) in the rates of success and survival of dental implants placed simultaneously with maxillary sinus floor augmentation (MSFA). Materials and Methods: Patients who visited the Department of Oral and Maxillofacial Surgery at Ulsan University Hospital from 2012 to 2014 and underwent simultaneous placement of implants with MSFA using ATB plus PRP were included in the study. Success and survival rates of the implants were evaluated based on the parameters of age and sex of the patient, site, follow-up period, residual bone height before surgery, diameter, and length of implant, sinus mucosa impairment, and postoperative complications. Result: A total of 23 patients and 67 implants were included in this study. The average age of the patients was $53.78{\pm}10.00$ years. The average follow-up period after installation of the prosthesis was $53{\pm}5$ months. The success and survival rates of the implants after placement of prosthesis were 95.52% and 97.01%, respectively. Conclusion: Combination of ATB and PRP showed high overall success rate, and it can be concluded that this combination is a predictable bone graft procedure for MSFA.

• 구강생물연구
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• 제42권4호
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• pp.228-234
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• 2018

The aim of this study was to determine the condition of supportive periodontal therapy (SPT) in implant patients and the effect of SPT on implant long-term survival. Implants placed at the Dept. of Periodontology, Chonnam National University Dental Hospital over a 5-year period, were traced for up to 8 years. Patients who had visited the hospital at least once a year were defined as regular SPT, and patients who were treated by active periodontal therapy were defined as patients with periodontitis. Kaplan-Meier survival analysis was performed based on the observation periods, and the effect of SPT and history of periodontitis on implant survival assessed by chisquare test. A total of 183 patients (age: 21-91, 98 males and 85 females), and 508 implants were used for this study. Three hundred eight implants were under SPT and 87 implants was under regular SPT. For the patients with periodontitis 136 implants were placed. The 5-year survival rate was 94.8%. The overall survival rate in patients who received SPT was 97.1% and 91.0% for those who did not (p=0.004). The survival rate in patients who received regular SPT was 97.7%, and 96.8% for patients received irregular SPT. The survival rate was 93.4% in patients with periodontitis and 95.2% in patients without periodontitis. Among patients with periodontitis, the survival rate was 100.0% in patients who received regular SPT and 89.2% for irregular SPT (p=0.012). These results suggest that regular SPT improves implant survival rate and is more effective in patients with periodontitis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권3호
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• pp.159-166
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• 2022

Objectives: The stability of crestal bone has been reported as a major factor in the success of dental implants. Implants can be placed in an equicrestal (crestal) or subcrestal position. The aim of this study was to evaluate the effect of implant depth placement on marginal bone loss. Materials and Methods: The study was created in a split-mouth design. Immediately after implant surgery, digital parallel radiographs were prepared and levels of bone were measured where marginal bone loss and bone level changes occurred. These measurements were repeated at 3-month and 6-month follow-up periods. Results: In this interventional study, 49 implants were evaluated in 18 patients. Primary bone height was not significant between the intervention and control groups in both mesial and distal aspects at 3 months and 6 months from the baseline. The mean marginal bone loss on the mesial side was 1.03 mm in the subcrestal group and 0.83 mm in the crestal group. In addition, mean marginal bone loss on the distal side was 0.88 mm and 0.81 mm in the subcrestal and crestal groups, respectively. Marginal bone loss was not significantly different between sexes, the maxilla or mandible, and in the anterior or posterior regions as well as between different lengths and diameters of implants. Conclusion: Based on the results of this study, there was no significant difference in terms of marginal bone loss between crestal and subcrestal implants.

• 대한치과보철학회지
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• 제35권2호
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• pp.255-264
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• 1997

The conventional osseointegration protocol calls for waiting up to 12 months for ossification of an extraction socket to heal before placing an endosseous implant. In this study, the possibility of placing a pure titanium implant directly into an extraction socket immediately after extraction was investigated. And the marginal bone loss of immediate nonsubmerged and submerged endosseous dental implants placed into extraction sockets was also compared. Pure titanium Nobelpharma Branemark implants and solid screw type ITI implants were placed into premolar extraction sockets of two adult dogs and allowed to heal for a period of 3 months, followed by functional loading of the implant. Radiographic examination was performed before implantation, immediately after implantation and 3, 6, 9, 12 months after implantation. The results obtained were as follows : 1. Immediately placed nonsubmerged ITI implants and submerged Branemark implants showed favorable radiographic osseointegration status and there were minimum marginal bone loss. 2. There were no significant differences in radiographic finding of osseointegration between conventional and immediate implantation. 3. Gingival tissue around implants showed more inflammatory signs than that of adjacent natural teeth. This study suggest that pure titanium Branemark implants and submerged ITI implants have the potential to integrate when placed immediatly after extraction of the teeth and warrants further investigation.

• Journal of Korean Dental Science
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• 제4권1호
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• pp.26-32
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• 2011

Purpose: The quality of implant surface is one of the factors that influence wound healing of implant site and subsequently affect osseointegration. The objective of modification of the surface properties of an implant is to affect the biological consequence. The purpose of this study is to evaluate the biologic response of osseous tissue to anodized implants. Materials and Methods: Two machined titanium implants for control group were installed in a tibia of each rabbit and two anodized implants for test group were installed in the other tibia of each rabbit. At the moment the implants were installed, resonance frequency analysis (RFA) values were measured. After healing periods of 1, 2, 3, and 7 weeks, the implants were uncovered and RFA values were measured again. Removal torque was measured for one implant in the test group and one implant in the control group. Histological evaluation was executed in the other implants. Results: Both of test group and control group have the tendency of greater RFA change rate and removal torque value as healing periods became longer, but were statistically insignificant (P>0.05). However, in the case of the same healing period, the test group tended to have greater RFA change rate and removal torque than the control group (P<0.05). More active new bone formation from endosteal surface was noted on the anodized surface than machined surface in specimen after 1 week. There were no significant differences between the test group and control group in histological evaluations. Conclusion: In summary, the anodized surface showed slightly favorable results and it is postulated that it may facilitate improved stability in bone.

• Journal of Periodontal and Implant Science
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• 제44권4호
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• pp.184-193
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• 2014

Purpose: The aim of the present study was to evaluate the in vivo accuracy of flapless, computer-aided implant placement by comparing the three-dimensional (3D) position of planned and placed implants through an analysis of linear and angular deviations. Methods: Implant position was virtually planned using 3D planning software based on the functional and aesthetic requirements of the final restorations. Computer-aided design/computer-assisted manufacture technology was used to transfer the virtual plan to the surgical environment. The 3D position of the planned and placed implants, in terms of the linear deviations of the implant head and apex and the angular deviations of the implant axis, was compared by overlapping the pre- and postoperative computed tomography scans using dedicated software. Results: The comparison of 14 implants showed a mean linear deviation of the implant head of 0.56 mm (standard deviation [SD], 0.23), a mean linear deviation of the implant apex of 0.64 mm (SD, 0.29), and a mean angular deviation of the long axis of $2.42^{\circ}$ (SD, 1.02). Conclusions: In the present study, computer-aided flapless implant surgery seemed to provide several advantages to the clinicians as compared to the standard procedure; however, linear and angular deviations are to be expected. Therefore, accurate presurgical planning taking into account anatomical limitations and prosthetic demands is mandatory to ensure a predictable treatment, without incurring possible intra- and postoperative complications.

• Imaging Science in Dentistry
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• 제51권2호
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• pp.93-106
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• 2021

Purpose: This study was conducted to review the literature regarding the types of cone-beam computed tomography (CBCT) artifacts around dental implants and the factors that influence their formation. Materials and Methods: A search strategy was carried out in the PubMed, Embase, and Scopus databases to identify published between 2010 and 2020, and 9 studies were selected. The implants included 306 titanium, titanium-zirconium, and zirconia implants, as well as 5 titanium cylinders. Results: The artifacts around the implants were the beam-hardening artifact, the streaking artifact, and band-like radiolucent areas. Some factors that influenced the formation of artifacts were the implant material, bone type, evaluated regions, distance, type of CBCT, field of view (FOV) size, milliamperage, peak kilovoltage (kVp), and voxel size. The beam-hardening artifact was the most widely reported, and it was minimized in protocols with a smaller FOV, larger voxels, and higher kVp. Conclusion: The risk and benefit of these protocols in individuals with dental implants must be considered, and clinical examinations and complementary radiographs play an essential role in implantology.

• The Journal of Advanced Prosthodontics
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• 제14권4호
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• pp.223-235
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• 2022

PURPOSE. To compare the clinical outcomes of two types of implant restoration for posterior edentulous area, 3-unit bridge supported by 2 implants and 3 implant-supported splinted crowns. MATERIALS AND METHODS. The data included 127 implant-supported fixed restorations in 85 patients: 37 restorations of 3-unit bridge supported by 2 implants (2-IB), 37 restorations of 3 implant-supported splinted crowns (3-IC), and 53 single restorations (S) as controls. Peri-implantitis and mechanical complications that occurred for 14 years were analyzed by multivariable Cox regression model. Kaplan-Meier curves and the multivariable Cox regression model were used to analyze the success and survival of implants. RESULTS. Peri-implantitis occurred in 28.4% of 2-IB group, 37.8% of 3-IC group, and 28.3% of S control group with no significant difference. According to the implant position, middle implants (P2) of the 3-IC group had the highest risk of peri-implantitis. The 3-IC group showed a lower mechanical complication rate (7.2%) than the 2-IB (16.2%) and S control group (20.8%). The cumulative success rate was 52.8% in S (control) group, 62.2% in 2-IB group, and 60.4% in 3-IC group. The cumulative survival rate was 98.1% in S (control) group, 98.6% in 2-IB group, and 95.5% in 3-IC group. There was no significant difference in the success and survival rate according to the restoration type. CONCLUSION. The restoration type was not associated with the success and survival of implants. The risk of mechanical complications was reduced in 3 implant-supported splinted crowns. However, the middle implants of the 3 implant-supported splinted crowns had a higher risk of peri-implantitis.

• 대한치과교정학회지
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• 제28권3호
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• pp.453-459
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• 1998

저자들은 임프란트 매식 후 골유착을 위한 초기 치유기간 이전에 악정형력이 임프란트 주위 조직에 미치는 영향을 관찰하기 위하여 가토 12마리의 양측 대퇴골에 임프란트를 식립하고 2주, 4주 그리고 6주후에 각각 300g의 악정형력을 Ni-Ti close coil spring을 이용하여 매식된 임프란트에 4주동안 가하고 관찰한 후 다음과 같은 결론을 얻었다. 1. 모든 실험군의 임프란트는 4주간의 악정형력 적용후에도 안정된 견고성을 유지하였다. 2. 2주 실험군에서 대조군에 비해 임프란트와 골조직 사이의 섬유조직 증식이 많이 관찰 되었으나 특이할만한 염증소견은 관찰되지 않았다. 3. 4주 실험군, 대조군에서는 2주 실험군, 대조군과 각각 비교하였을 때 보다 많은 양의 골재생이 관찰 되었으며 실험군과 대조군 모두에서 임프란트와 골조직 사이의 섬유조직은 관찰하기 힘들었다. 4. 6주에서는 실험군과 대조군 사이에 뚜렷한 차이가 발견되지 않았다. 이상의 결과로 보아 임프란트 주위의 골조직 재생이 충분하지 않아도 골의 양과 질이 우수해 임프란트 식립시 견고한 초기고정을 얻을 수 있다면 골유착이 완성되는 초기 치유기간 이전에도 치과교정적 고정원으로 사용가능할 것으로 사료된다.