• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• Imaging Science in Dentistry
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• v.48 no.3
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• pp.191-199
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• 2018

Purpose: This study classified alveolar arch forms and evaluated differences in alveolar bone thickness among arch forms in the anterior esthetic region using cone-beam computed tomography (CBCT) images. Materials and Methods: Axial views of 113 CBCT images were assessed at the level of 3 mm below the cementoenamel junction (CEJ) of the right and left canines. The root center points of teeth in the anterior esthetic region were used as reference points. Arch forms were classified according to their transverse dimensions and the intercanine width-to-depth ratio. The buccolingual alveolar bone thickness of each tooth was measured at 3 mm below the CEJ and at the mid-root level. Differences in the mean thicknesses among arch forms were analyzed. Results: Anterior maxillary arches could be classified as long narrow, short medium, long medium, and long wide arches. Significant differences in buccolingual alveolar bone thickness among the arch groups were found at both levels. The long wide arches presented the greatest bone thickness, followed by the long medium arches, while the long narrow and short medium arches were the thinnest. Conclusion: Arch forms were classified as long narrow, short medium, long medium, and long wide. The buccolingual alveolar bone thickness exhibited significant differences among the arch forms.

• Journal of Periodontal and Implant Science
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• v.52 no.6
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• pp.496-508
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• 2022

Purpose: This study aimed to compare the long-term survival rate and peri-implant marginal bone loss between different types of dental implant-abutment connections. Methods: Implants with external or internal abutment connections, which were fitted at Gangneung-Wonju National University Dental Hospital from November 2011 to December 2015 and followed up for >5 years, were retrospectively investigated. Cumulative survival rates were evaluated for >5 years, and peri-implant marginal bone loss was evaluated at 1- and 5-year follow-up examinations after functional loading. Results: The 8-year cumulative survival rates were 93.3% and 90.7% in the external and internal connection types, respectively (P=0.353). The mean values of marginal bone loss were 1.23 mm (external) and 0.72 mm (internal) (P<0.001) after 1 year of loading, and 1.20 mm and 1.00 mm for external and internal abutment connections, respectively (P=0.137) after 5 years. Implant length (longer, P=0.018), smoking status (heavy, P=0.001), and prosthetic type (bridge, P=0.004) were associated with significantly greater marginal bone loss, and the use of screw-cement-retained prosthesis was significantly associated (P=0.027) with less marginal bone loss. Conclusions: There was no significant difference in the cumulative survival rate between implants with external and internal abutment connections. After 1 year of loading, marginal bone loss was greater around the implants with an external abutment connection. However, no significant difference between the external and internal connection groups was found after 5 years. Both types of abutment connections are viable treatment options for the reconstruction of partially edentulous ridges.

• Journal of Korean society of Dental Hygiene
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• v.12 no.4
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• pp.759-770
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• 2012

Objectives : The purpose of this study was to examine the awareness of implant wearers about periodontal diseases and implant management, which were closely linked to implant durability, in an effort to obtain information on the right directions for oral health education related to implant self-care and specialized care. Methods : The subjects in this study were 217 patients who wore implant and visited 14 different dental hospitals and clinics in the metropolitan area. After a questioaire survey was conducted and collected data were analyed by the statistical package SPSS 18.0. Results : As for the awareness of the subjects on the regeneration of alveolar ridge by general characteristics, there were statistically significant intergroup gaps according to the number of possessed implant, implant satisfaction and subjective gingival health status(p<0.05). Regarding their awareness of implant durability by general characteristics, there were statistically significant gaps according to the number of possessed implant and oral health education experience(p<0.05). Concerning their awareness of the cycle of regular implant checkup by general characteristics, there were statistically significant gaps according to occupation, subjective gingival health status and oral health education experience(p<0.05). Conclusions : The above-mentioned findings suggest that in order to ensure the long-term safe maintenance of implant, the way of looking at periodontal diseases and implant management should be changed. Specifically, more intensive oral health education should be provided for implant wearers to be aware of the importance of self-care and specialized care to change their oral health behavior, and clinical dental hygienists should improve their role performance to make it happen.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.2
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• pp.274-282
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• 2007

Statement of problem: Main consideration was given to the stresses at the site of implant entry into the cortical bone at the alveolar crest. As a suspectible factor affecting the occurrence of stress concentrations, the contact angle between the implant and the alveolar crest bone was addressed. Purpose: The purpose of this study is to evaluate angles between the alveolar crest bone and the implant effect on the implant crestal area induced stresses using a finite element method. Material and methods: Cylindrically shaped, standard size ITI implants entering into alveolar crest with four different contact angles of 0, 15, 30, and 45 deg. with the long axis of the implant were axisymmetrically modelled. Alterations of stresses around the implants were computed and compared at the cervical cortical bone. Results and conclusion: The results demonstrated that regardless of the difference of the implant/alveolar crest bone contact angles, stress concentration occurred at the cervical bone and the angle differences led to insignificant variations in stress level.

• Archives of Plastic Surgery
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• v.42 no.1
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• pp.4-10
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• 2015

Mammary implants marketed by Poly Implant Proth$\grave{e}$se (PIP) were found to contain industrial grade silicone and this caused heightened anxiety and extensive publicity regarding their safety in humans. These implants were used in a large number of patients worldwide for augmentation or breast reconstruction. We reviewed articles identified by searches of Medline, PubMed, Embase, and Google Scholar databases up to May 2014 using the terms: "PIP", "Poly Implant Proth$\grave{e}$se", "breast implants" and "augmentation mammoplasty" "siloxanes" or "silicone". In addition the websites of regulating bodies in Europe, USA, and Australia were searched for reports related to PIP mammary implants. PIP mammary implants are more likely to rupture than other implants and can cause adverse effects in the short to the medium term related to the symptoms of rupture such as pain, lumps in the breast and axilla and anxiety. Based on peer-reviewed published studies we have calculated an overall rupture rate of 14.5% (383/2,635) for PIP implants. However, there is no evidence that PIP implant rupture causes long-term adverse health effects in humans so far. Silicone lymphadenopathy represents a foreign body reaction and should be treated conservatively. The long-term adverse effects usually arise from inappropriate extensive surgery, such as axillary lymph node dissection or extensive resection of breast tissue due to silicone leakage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.33.1-33.10
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• 2017

Dental implants are a common treatment for the loss of teeth. This paper summarizes current knowledge on implant surfaces, immediate loading versus conventional loading, short implants, sinus lifting, and custom implants using three-dimensional printing. Most of the implant surface modifications showed good osseointegration results. Regarding biomolecular coatings, which have been recently developed and studied, good results were observed in animal experiments. Immediate loading had similar clinical outcomes compared to conventional loading and can be used as a successful treatment because it has the advantage of reducing treatment times and providing early function and aesthetics. Short implants showed similar clinical outcomes compared to standard implants. A variety of sinus augmentation techniques, grafting materials, and alternative techniques, such as tilted implants, zygomatic implants, and short implants, can be used. With the development of new technologies in three-dimension and computer-aided design/computer-aided manufacturing (CAD/CAM) customized implants can be used as an alternative to conventional implant designs. However, there are limitations due to the lack of long-term studies or clinical studies. A long-term clinical trial and a more predictive study are needed.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.4
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• pp.341-348
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• 2006

Accurate fit of the implant prosthesis is important in ensuring long term success of osseointegrated implant. Inaccurate fit of the implant prosthesis may give rise to complications and mechanical failure. To evaluate fite of the implant prosthesis, the development of the methods of analyzing the degree of misfit is important in clinical practice. To analyze the degree of the misfit of implant prosthesis, modal testing was used. A 2-dimensional finite element modal testing was accomplished. Four 2-dimensional finite element models with various levels of misfit of implant prostheses were constructed. Thickness gauges were simulated to make misfit in the implant prostheses. With eigenvalue analysis, the natural frequencies of the models were found in the frequency domain representation of vibration. According to the difference of degree of misfit, natural frequencies of the models were changed.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.3
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• pp.251-260
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• 2006

Accurate fit of the implant prosthesis is important in ensuring long term success of osseointegrated implant. Inaccurate fit of the implant prosthesis may give rise to complications and mechanical failure. To evaluate fite of the implant prosthesis, the development of the methods of analyzing the degree of misfit is important in clinical practice. To analyze the degree of the misfit of implant prosthesis, modal testing was used. A 2-dimensional finite element modal testing was accomplished. Four 2-dimensional finite element models with various levels of misfit of implant prostheses were constructed. Thickness gauges were simulated to make misfit in the implant prostheses. With eigenvalue analysis, the natural frequencies of the models were found in the frequency domain representation of vibration. According to the difference of degree of misfit, natural frequencies of the models were changed.

• The Journal of Advanced Prosthodontics
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• v.14 no.4
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• pp.236-249
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• 2022

PURPOSE. The present study compared the accuracy between digital and conventional implant impressions. MATERIALS AND METHODS. The experimental models were divided into six groups depending on the implant location and the scanning span. Digital impressions were captured using the intraoral optical scanner TRIOS (3Shape, Copenhagen, Denmark). Conventional impressions were taken with the monophase impression material based on addition-cured silicones, Honigum-Mono (DMG, Hamburg, Germany). A high-precision laboratory scanner D900 (3Shape, Copenhagen, Denmark) was used to obtain digital data of resin models and stone casts. Surface tessellation language (STL) datasets from scanner were imported into the analysis software Geomagic Qualify 14 (3D Systems, Rock Hill, SC, USA), and scan body deviations were determined through two-dimensional and three-dimensional analyses. Each scan body was measured five times. The Sidak t test was used to analyze the experimental data. RESULTS. Implant position and scanning distance affected the impression accuracy. For a unilateral arch implant and the mandible models with two implants, no significant difference was observed in the accuracy between the digital and conventional implant impressions on scan bodies; however, the corresponding differences for trans-arch implants and mandible with six implants were extremely significant (P<.001). CONCLUSION. For short-span scanning, the accuracy of digital and conventional implant impressions did not differ significantly. For long-span scanning, the precision of digital impressions was significantly inferior to that of the traditional impressions.