• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.80-88
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• 2018

Purpose: Implant surface modification and implant design are the principle targets for achieving successful primary stability. The aim of this study was to measure implant stability quotient (ISQ) values of sandblasted, large-grit, acid-etched (SLA) implants with tapered straight body design during the healing period, and to determine the various factors affecting implant stability. Materials and Methods: To measure implant stability, resonance frequency analysis (RFA) was performed in 26 patients (13 women and 13 men) with 44 SLA implants with tapered straight body design. Implant stability (ISQ values) was evaluated at baseline and healing abutment connection (12 weeks), and the correlations between RFA and insertion torque (IT), bone quality, and jawbone were determined. Results: The mean ISQ value of the implants was $69.4{\pm}10.2$ at the time of implant placement (baseline) and $81.4{\pm}6.9$ at the time of healing abutment connection (P < 0.05). Significant differences were found between RFA and bone quality and between RFA and jawbone (P < 0.05). No significant differences were found between RFA and IT, insertion area, fixture diameter, and implant length (P > 0.05). Conclusion: ISQ values of SLA implants with tapered straight body design were high at baseline and healing abutment connection. It was concluded that SLA implants with tapered straight body design show improved primary and secondary stability, and that immediate or early loading may be applicable.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.337-346
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• 2013

It is necessary to consider the median lingual foramen carefully to prevent the bleeding due to the damage of the sublingual artery for implant surgery. This study is to evaluate the frequency, location, diameter and the number of the Mandibular median lingual foramen regarding gender and age in the CBCT. Sixty two images of cone beam computed tomography (CBCT) whose visited the Chonnam National University Dental hospital from Sept. 2010 to Apr. 2011 were evaluated. Frequency, number, location and the diameter of Mandibular median lingual foramen shown in the CBCT image were evaluated. Sixty two patients (100%) had at least one median lingual foramen and fifty six patients (90.32%) had multiple foramens. Forty patients (66.13%) showed the median lingual foramen on the location between Mn. central incisors. The mean vertical position of the genial spine and the median lingual foramen was 24.21 mm and 14.52 mm, respectively. And the relative mean vertical dimension of median lingual foramen was 0.45. The mean diameter of the foramen was 0.93 mm. CBCT demonstrated the frequency, location, diameter and the number of median lingual foramen. It is necessary to take CBCT before implant placement to prevent the bleeding.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.116-126
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• 2018

Purpose: The purpose of this study was to analyze the factors affecting the survival rate and the marginal bone level of dental implants that have functioned over 7-years. Materials and Methods: In 92 patients, 178 dental implants were included. Implant-related factors (diameter, length, prosthetic splint), patient-related factors (gender, smoking, plaque index, compliance to supportive periodontal therapy) and surgery-related factors (proficiency of surgeon, bone graft) were evaluated via clinical and radiographic examination. The marginal bone level was determined by intraoral standard radiography at the mesial and distal aspects of each implant using an image analysis software program. Results: The survival rate of all the implants was 94.94% and the marginal bone level was $0.89{\pm}1.05mm$, these results are consistent with other studies that present long-term good clinical results. Implant length and plaque index among several factors were statistically significant for implant survival rate (P < 0.05). Smoking and the presence of regeneration surgery were statistically significant for the marginal bone level (P < 0.05). Conclusion: Dental implant that have functioned over 7-years showed favorable long-term survival rates and marginal bone level. Implant length and plaque control should be considered for improving the long-term clinical results. It is needed that careful application of bone regeneration technique and smoking control for maintaining of marginal bone level.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.253-258
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• 2014

This case report shows an early loading at the maxillary posterior area with the wide diameter implant which has a deepened threads after removal of failed implant. Implant Stability Quotient (ISQ) value has represented favorable result for one year. This clinical report describes the potential of early loading on a maxillary posterior single implant with deepened threads.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.1
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• pp.10-19
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• 2015

Purpose: The aim of the present study was to evaluate the long-term survival of implants retrospectively and determine the risk factors associated with implant failure. Materials and Methods: Of all implants that were placed at the Department of Periodontology of the Dental Hospital of Gangneung-Wonju National University from January 1998 to December 2012, 2265 implants that were followed up until June 2013 were included in this study. Data were collected from clinical and radiographic examinations from previous visits. The information gathered included gender, age, smoking status, implant diameter, implant length, surface of implant, location of implant within the dental arch, surgical techniques and existence of complications. Results: The survival rate before loading was 98.9%. The cumulative survival rate after 5 years of loading was 97.2%, and after 15 years of loading was 95.2%. In a simple logistic regression analysis, gender (P = 0.016), smoking status (P = 0.001), location of implant (P = 0.020) and existence of complications (P = 0.002) were statistically associated with implant failure and included in the multiple regression analysis. As a result of multiple logistic regression analysis, the variables statistically associated with implant failure (P < 0.05) were smoking status (P = 0.049) and existence of complications (P < 0.001). Conclusion: The cumulative survival rate of dental implants after 15 years of loading was 95.2% and that the variables statistically associated with implant failure were smoking status and existence of complications.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.103-109
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• 2016

Purpose: This study is to evaluate the clinical significance of implantation with simultaneous bone graft by comparing the marginal bone loss around maxillary anterior implants with or without bone graft. Materials and methods: Patients treated with implant-retained restorations on maxillary anterior region at Implant Center, Dental Hospital, Wonkwang University between June 2011 and May 2014 were included in this study. Date of implant placement, implant diameter, implant length, implant-abutment connection type and whether the bone graft was done were investigated. The patient's periapical radiographs taken immediately after implantation and at the most recent visit were compared. Marginal bone loss was measured using Emago advanced v5.6 program (Oral diagnostic systems, Amsterdam, Netherlands). Statistical analysis was done in independent t-test by using SPSS 22.0 program. Results: As a result of observing on 83 implants (without bone graft: 44, with bone graft: 39) of 52 patients for 6 - 45 months (average: 18.4 months), implants without bone graft showed $1.42{\pm}0.42mm$, implants with bone graft showed $1.28{\pm}0.45mm$ of marginal bone loss. Conclusion: In limitations of this study, implants with simultaneous bone graft had significantly less marginal bone loss than implants without bone graft.

• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.153-161
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• 2005

파이브로넥틴은 세포외기질에 존재하는 당단백질로 세포의 부착, 이동, 성장 및 분화에 관여하며, 섬유아세포 성장인자는 세포의 증식 이동 및 분화에 영향을 주는 중요한 성장인자로 알려져 있다. 최근 연구에 의하면, 파이브로넥틴은 조골세포의 타이태늄 임플란트 표면으로 이주와 증식 및 골생성을 촉진하며, 섬유아세포 성장 인자는 파이브로넥틴에 상승작용을 한다고 보고된 바 있다. 이 실험의 목적은 파이브로넥틴 및 섬유아세포 성장인자의 복합 단백질을 이용하여 타이태늄 임플란트의 골 반응을 알아보는 것이다. 체중 2.5 kg 내외의 건강한 18 마리의 웅성가토를 준비하여 무균 사육하였고, 순수 타이태늄을 절삭가공하여 직경 3.5mm, 길이 6mm 의 machined surface를 지니는 screw type 의 임플란트를 준비하였다. 사람의 유전자를 기초로, 유전자 재조합법을 통해, 적절한 primer를 이용하여 얻은 섬유아세포 성장인자를 파이브로넥틴 III 형 분절의 9-10 번 도메인에 결합시켜 얻은 복합 단백질을 준비된 임플란트에 표면처리하여 실험군으로 하였고, 표면처리하지 않은 임플란트를 대조군으로 하여, 가토의 좌우 경골에 각각 2 개씩의 임플란트를 식립하였다. 4주 후, 가토를 희생시켜 각 경골 당 한 개의 임플란트에서 뒤틀림 제거력을 측정하였고 나머지 임플란트 식립 부위 에서는 경골을 포함하는 조직표본을 제작하였다. 조직표본상에서 골접촉이 가장 좋은 3 개의 나사산의 길이를 측정하고, 나사와 접촉하는 골의 길이를 측정하여 골-임플란트 접촉도를 구하고, 같은 부위에서 나사산 사이의 면적과 골이 차지하는 면적을 비교하여 골생성률을 얻었다. 실험군과 대조군의 결과는 Student t-test 를 이용하여 신뢰도 95% 수준에서 통계학적 유의성을 검정하였다. 파이브로넥틴과 섬유아세포 성장인자의 복합 단백질로 표면처리된 임플란트와 표면처리를 하지 않은 임플란트는 뒤틀림 제거력에서는 통계적 유의성이 나타나지 않았으나, 골-임플란트 접촉도와 골생성률에서 복합 단백질로 처리된 임플란트가 통계적으로 유의하게 높은 결과를 보였다. 이상의 연구결과로, 섬유아세포 성장인자와 파이브로넥틴 복합 단백질로 처리한 타이태늄 임플란트가 주변 골 형성을 촉진시켜, 골유합을 증진시킴을 알 수 있었다. 따라서, 복합 단백질이 타이태늄 임플란트의 성공률을 높이기 위한 표면개질 물질로 이용될 가능성을 확인할 수 있었다.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.27 no.2
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• pp.97-104
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• 2018

Mandibular anterior region has high implant survival rates and better accessibility compared with any other region. Even if there are possibilities for perforation on lingual cortical bone due to improper drilling and bleeding caused by lingual artery damage, mandibular anterior region is a safe region because less amount of major anatomical structures exist compared with other regions. However, because of narrow bucco-lingual width of alveolar ridge, it is challengeable to obtain esthetic implant prosthesis. Although patients are less sensitive subjectively, mandibular anterior region is as difficult as maxillary anterior region in that implant placement location plays a critical role on the prognosis of implant prosthesis. One-piece implant is a very useful option for mandibular anterior region. Considering the narrow roots and thin alveolar bone of mandible, it is clinically difficult for implant diameter to be greater than 3mm In this case, we could approach the esthetic restoration in mandibular anterior region with one-piece implant and immediate loading.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2197-2202
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• 2011

In this study, we propose a new short dental implant and investigate its bio-mechanical characteristics by using three dimensional finite element analyses. The proposed dental implant has the central cavity which can be integrated with the core of cancellous bone remained by trepanning drill. We take the Bicon short implant as a reference model for studying the effects according to the shape of cavity. The parametric finite element model using ANSYS APDL has been built to determine which length, diameter and thread of central cavity would be effective to dissipate stress. The reduction of undesirable stress in adjacent bone which can suppress bone defects and the eventual failure of implants. The numerical results shows that the cavity of well-determined shape has the beneficial effects on reducing the bone absorption in cancellous bone.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.4
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• pp.280-292
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• 2016

Purpose: The purpose of this study was to compare the long-term survival rate and peri-implant marginal bone loss related to multiple risk factors including the clinician's experience. Materials and Methods: Four hundred twenty implants in 146 patients, who had involved a supportive periodontal therapy program every 3 to 6 months and had follow up data for at least 5 years, were selected as the study group. Peri-implant marginal bone loss, data of demographic, implant and surgical characteristics were collected from peri-apical radiographs and chart review. Implant survival was regarded as the remaining with radiographic marginal bone level in excess of 50% of the fixture length for any reason. Results: The cumulative survival rate after 5 years of loading was 94.9%. In binary logistic regression analysis, smoking status (P = 0.033) and presence of spontaneous cover screw exposure (P < 0.001) were significantly related to 5-year survival of implants. In stepwise multiple regression analysis, smoking status (P < 0.001), type of abutment connection (P < 0.001) and implant surface (P = 0.033) were significantly related to peri-implant marginal bone level. And the year of resident was not statistically related to 5-year implant survival in simple logistic regression analysis (P = 0.171). Conclusion: Smoking status, spontaneous cover screw exposure, type of abutment connection and implant surface might influence the implant success. There was no significant correlation between the year of resident and implant failure.