• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.178-185
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• 2015

Purpose: The purpose of this study was to conduct a comparative assessment on the satisfaction level for the two interfaces of surgical guide system (SimPlant and R2GATE), the design and convenience of manufactured surgical guides and the importance of using the surgical guides thereof by means of survey. Materials and Methods: Hereupon, they simulated the implant surgical process by mounting the two manufactured systems of surgical guide on a dental mold, respectively. The study subjects were instructed to complete the questionnaire as to the satisfaction level upon completion of the simulated surgery. This study summarized the data of each question after collecting the completed questionnaires. Then, this study analyzed the summarized data by utilizing statistical program SPSS 20.0 (IBM). Results: R2GATE had a higher value of the satisfaction level on the design and convenience of manufactures surgical guides. R2GATE group ($7.33{\pm}1.26$) was found to have a higher value in terms of the overall satisfaction level compared to SimPlant group ($6.67{\pm}1.26$) (${\alpha}$ = 0.05). Conclusion: The user satisfaction level on the surgical guide manufactured for R2GATE system was to such an extent as it can be widely used in clinical environment. Moreover, the surgical guide manufactured as R2GATE system can guide both the length and direction of a drill simultaneously. As a result, it is highly recommended for those beginners who do not have a lot of experience in implant placement.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.2
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• pp.113-132
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• 2005

The purpose of this study was to assess the stress-induced pattern at the supporting bone, the implant fixture, the abutment and the abutment screw according to a friction-fit joint (Astra; Model 1) or slip- fit joint (Frialit-2; Model 2) in the internal connection system under vertical and inclined loading using finite element analysis. In conclusion, in the internal connection system of the implant and the abutment connection methods, the stress-induced pattern at the supporting bone, the implant fixture, the abutment and the abutment screw according to the abutment connection form had difference among them, and the stress distribution pattern usually had a widely distributed tendency along the inner surface of the implant fixture contacting the abutment post. The magnitude of the stress distributed in the supporting bone, the implant fixture, the abutment and the abutment screw was higher in the friction-fit joint than in the slip-fit joint. But it is considered that the further study is necessary about how this difference in the magnitude of the stress have an effect on the practical clinic.

• The Journal of Advanced Prosthodontics
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• v.4 no.4
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• pp.254-258
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• 2012

Implant-supported overdenture is a reliable treatment option for the patients with edentulous mandible when they have difficulty in using complete dentures. Several options have been used for implant-supported overdenture attachments. Among these, bar attachment system has greater retention and better maintainability than others. SFI-Bar$^{(R)}$ is prefabricated and can be adjustable at chairside. Therefore, laboratory procedures such as soldering and welding are unnecessary, which leads to fewer errors and lower costs. A 67-year-old female patient presented, complaining of mobility of lower anterior teeth with old denture. She had been wearing complete denture in the maxilla and removable partial denture in the mandible with severe bone loss. After extracting the teeth, two implants were placed in front of mental foramen, and SFI-Bar$^{(R)}$ was connected. A tube bar was seated to two adapters through large ball joints and fixation screws, connecting each implant. The length of the tube bar was adjusted according to inter-implant distance. Then, a female part was attached to the bar beneath the new denture. This clinical report describes two-implant-supported overdenture using the SFI-Bar$^{(R)}$ system in a mandibular edentulous patient.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.425-428
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• 2000

In this paper the impact force which occurs on each tooth of jaw-bones while masticating is calculated through the rigid body dynamic analysis. This analysis is done by ADAMS. The impact force calculated in this paper is required for the structural stress analysis of implant system which is needed for the implant system design. The analysis results show that the impact time decreases as the impact force increases, the largest impact force occurs on the front tooth and the impact force is almost normal to the tooth surface together with slight tangential force.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.24-30
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• 2018

Dental implants are currently widely used as artificial teeth due to their good chewing performance and long life cycle. A dental implant consists of an abutment as the upper part and a fixture as the lower part. When chewing forces are repeatedly applied to a dental implant, gap at the interface surface between the abutment and the fixture is often occurred, and results in some deteriorations such as loosening of fastening screw, dental retraction and fixture fracture. To cope with such problems, a sealing-type abutment having a number of grooves along the conical-surface circumference was previously developed, and shows better sealing performance than the conventional one. This study carries out optimization of the groove shape by genetic algorithm(GA) as well as structural analysis in consideration of external chewing force and pretension between the abutment and the fixture. The overall optimization system consists of two subsystems; the one is the genetic algorithm with MATLAB, and the other is the structural analysis with ANSYS. Two subsystems transmit and receive the relevant data with each other throughout the optimization processes. The optimization result is then compared with that of the conventional one with respect to the contact pressure and the maximum stress. The result shows that the optimized model gives better sealing performance than the conventional sealing abutment.

• Journal of Yeungnam Medical Science
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• v.36 no.1
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• pp.43-49
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• 2019

Background: In the osseointegration of dental implants, the implant surface properties have been reported to be some of the most important critical factors. The effect of implant's surfaces created by resorbable blast media (RBM) followed by laser ablation on bone tissue reactions was examined using the removal torque test and histomorphometric analysis. Methods: Two types of dental implants, RBM-laser implants (experimental group) and RBM implants (control group) (CSM implant system, Daegu, Korea; L=6 mm, diameter=3.75 mm) were placed into the right and left distal femoral metaphysis of 17 adult rabbits. Six weeks after placement, removal torque was measured and histomorphometric analysis was performed. Results: The mean removal torque was $24.0{\pm}10.2Ncm$ and $46.6{\pm}16.4Ncm$ for the control and test specimens, respectively. The experimental RBM-laser implants had significantly higher removal torque values than the control RBM implants (p=0.013). The mean values of total and cortical bone to implant contact (BIC) were respectively $46.3{\pm}10.8%$ and $65.3{\pm}12.5%$ for the experimental group, and $41.9{\pm}18.5%$ and $57.6{\pm}10.6%$ for the control group. The experimental RBM-laser implants showed a higher degree of total and cortical BIC compared with RBM implants, but there was no statistical significance (p=0.482, 0.225). Conclusion: The removal torque and BIC of the test group were higher than those of the control group. In this study, the surface treatment created by RBM treatment followed by laser ablation appears to have a potential in improving bone tissue reactions of dental implants.

• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.150-157
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• 2016

PURPOSE. The modified lateral-screw-retained implant prosthesis (LSP) is designed to combine the advantages of screw- and cement-retained implant prostheses. This retrospective study evaluated the mechanical and biological complication rates of implant-supported single crowns (ISSCs) inserted with the modified LSP in the posterior region, and determined how these complication rates are affected by clinical factors. MATERIALS AND METHODS. Mechanical complications (i.e., lateral screw loosening [LSL], abutment screw loosening, lateral screw fracture, and ceramic fracture) and biological complications (i.e., peri-implant mucositis [PM] and peri-implantitis) were identified from the patients' treatment records, clinical photographs, periapical radiographs, panoramic radiographs, and clinical indices. The correlations between complication rates and the following clinical factors were determined: gender, age, position in the jaw, placement location, functional duration, clinical crown-to-implant length ratio, crown height space, and the use of a submerged or nonsubmerged placement procedure. RESULTS. Mechanical and biological complications were present in 25 of 73 ISSCs with the modified LSP. LSL (n=11) and PM (n=11) were the most common complications. The incidence of mechanical complications was significantly related to gender (P=.018). The other clinical factors were not significantly associated with mechanical and biological complication rates. CONCLUSION. Within the limitations of this study, the incidence of mechanical and biological complications in the posterior region was similar for both modified LSP and conventional implant prosthetic systems. In addition, the modified LSP is amenable to maintenance care, which facilitates the prevention and treatment of mechanical and biological complications.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.4
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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.

• Journal of Periodontal and Implant Science
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• v.42 no.1
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• pp.25-29
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• 2012

Purpose: There has been no attempt to establish an objective implant surgical evaluation protocol to assess residents' surgical competence and improve their surgical outcomes. The present study presents a newly developed assessment and rating system and simulation model that can assist the teaching staffs to evaluate the surgical events and surgical skills of residents objectively. Methods: Articles published in peer-reviewed English journals were selected using several scientific databases and subsequently reviewed regarding surgical competence and assessment tools. Particularly, medical journals reporting rating and evaluation protocols for various types of medical surgeries were thoroughly analyzed. Based on these studies, an implant surgical technique assessment and rating system (iSTAR) has been developed. Also, a specialized dental typodont was developed for the valid and reliable assessment of surgery. Results: The iSTAR consists of two parts including surgical information and task-specific checklists. Specialized simulation model was subsequently produced and can be used in combination with iSTAR. Conclusions: The assessment and rating system provided may serve as a reference guide for teaching staffs to evaluate the residents' implant surgical techniques.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.9-15
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• 2014

Purpose: Implant engine system is composed of the handpiece, micromotor, control box and foot switch. The aim of this study was to evaluate the satisfaction of the implant engine systems in terms of convenience-design and to examine the relation with the experience of implant surgery. Materials and Methods: Three implant systems were evaluated: SurgicXT/X-SG20L, INTRAsurg300/CL3-09, XIP10/CRB26LX. For this comparative study, 30 dentists were included and the satisfaction was measured using a structured questionnaire. One-way analysis of the variance (ANOVA) and multiple regression analysis were used within and between the groups. Results: Total satisfaction differed from each other (P < 0.05). The convenience score was more associated with the total satisfaction than design score. Moreover, the implant surgery experience affected several assessments. Conclusion: Collectively, in a cross-sectional study model, the design of implant system significantly affects its total satisfaction and the surgery experience can be influential factor in the evaluation of implant engine system.