• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.125-136
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• 2008

Statement of problem: Since the concept of osseointegration in dental implants was introduced by $Br{{\aa}}nemark$ et al, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. Purpose: The aim of this retrospective study was to provide long-term data on the $Neoplan^{(R)}$ implant, which features a sandblasted and acid-etched surface and external connection. Material and methods: 96 $Neoplan^{(R)}$ implants placed in 25 patients in Yonsei University Hospital were examined to determine the effect of the factors on marginal bone loss, through clinical and radiographic results during 18 to 57 month period. Results: 1. Out of a total of 96 implants placed in 25 patients, two fixtures were lost, resulting in 97.9% of cumulative survival rate. 2. Throughout the study period, the survival rates were 96.8% in the maxilla and 98.5% in the mandible. The survival rates were 97.6% in the posterior regions and 100% in the anterior regions. 3. The mean bone loss for the first year after prosthesis placement and the mean annual bone loss after the first year for men were significantly higher than that of women (P<0.05). 4. The group of partial edentulism with no posterior teeth distal to the implant prosthesis showed significantly more bone loss compared to the group of partial edentulism with presence of posterior teeth distal to the implant prosthesis in terms of mean bone loss for the first year and after the first year (P<0.05). 5. The mean annual bone loss after the first year was more pronounced in posterior regions compared to anterior regions (P<0.05). 6. No significant difference in marginal bone loss was found in the following factors: jaws, type of prostheses, type of opposing dentition, and submerged /non-submerged implants (P<0.05). Conclusion: On the basis of these results, the factors influencing marginal bone loss were gender, type of edentulism, and location in the arch, while the factors such as arch, type of prostheses, type of opposing dentition, submerged / non- submerged implants had no significant effect on bone loss. In the present study, the cumulative survival rate of the $Neoplan^{(R)}$ implant with a sandblasted and acid-etched surface was 97.9% up to a maximum 57-month period. Further long-term investigations for this type of implant system and evaluation of other various domestic implant systems are needed in future studies.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.1
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• pp.80-86
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• 2016

A few authors have reported good clinical results using double crown removable partial denture (RPD) with a few remaining teeth. Hybrid telescopic double crown is a good indication for a patient with poor periodontal condition and/or few remaining teeth after extraction, especially located in cross-arch position. In this case, there was a poor periodontal condition with teeth mobility. Several teeth with poor prognosis were extracted. Remaining anterior teeth was restored with fixed prostheses and edentulism was restored with Kennedy class I removable partial denture in maxilla. In mandible, it was hard to restore with clasp removable partial prostheses because of bilaterally isolated remaining teeth so that hybrid double crown removable partial denture with friction pin was suitable for this case. The objective of this report is to discuss the characteristics and the utility of hybrid double crown prostheses using a few remaining teeth in mandible.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.1
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• pp.46-50
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• 2015

Restoration of a patient with thin and low residual ridges using a removable partial denture cannot provide proper anterioposterior stability and support, so it results in patient discomfort and severe occlusal force. Also, when a small number of residual teeth are far apart from one another, it is difficult to splint. When these teeth are not splinted, they become solitary abutments, which is not a wise treatment decision. In this case, telescopic system reduces severe lateral load on abutments resulting from a clasp denture and it provides stable and definite retention and solidity. In this case report, a patient exhibited full edentulism in maxilla, and a small number of residual teeth in mandible, which were restored with a complete denture and a telescopic denture respectively. In treatment planning, it was concluded that a patient was restored with a telescopic denture since it was highly probable that a clasp denture would create discomfort and difficulty due to a small number of residual teeth located far apart and residual ridges without proper support.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.1-32
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• 1991

Tho osseointegrated dental prosthetic treatment has develped for the edentulous patient with severely resorbed alveolar ridge, and has given us a successful clinical results to date. Nowadays the partially edentulism is included among the indications of the osseointegrated prosthetic treatment. The purpose of this study was to analyze the stress distribution at supporting bone according to the types of connection modality between implant and tooth in the superstructure. Two dimensional finite element stress analysis was applied for this study. FEM models were created using software Super SAP for MBM 16bit personal computer. Three modalities of connection were modeled and analyzed under load condition. The results were as follws: 1. The stress develped at tooth and implant in the cancellous bone was lower in the case of rigid connection than in the case of norigid connection, but higher between the two implants in the case of rigid connection than in the case of nonrigid connection. 2. The stress developed at the cortical bone and at the supporting bone interface was lower in the case of rigid connection than in the case of nonrigid connection 3. The stress developed at the supporting tissue interface of the implant nearby the tooth, was lower in the case of rigid connection than in the case of nonrigid connection. 4. The stress developed at the supporting tissue interface of posteriormost implant, was same between the cases of rigid and nonrigid connection. 5. The stress distribution related to the freestanding case was generally similar to the stress distribution pattern of nonrigid connection case. 6. The magnitude of applied load which produces deformation within elastic limit, had influence on the absolute value of stress, but had no influence on the pattern of stress distribution of the same case.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.1
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• pp.31-39
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• 2018

The collapse of the posterior occlusion destroys the normal occlusal plane and causes excessive wear reducing the vertical dimension. Reduced vertical dimension of occlusion causes not only aesthetic and functional problems but also overloading on the temporomandibular joints and abnormalities of muscle nerve system. In order to improve the collapsed occlusal relationship, it is necessary to consider the change of the vertical dimension. It is necessary to make a precise diagnosis and analysis before the treatment and to evaluate the adaption of patient to the new vertical dimension of occlusion. A patient with excessive overbite often has occlusal problems of tooth wear and tooth eruption. Considering these considerations, overall prosthodontic restoration is required to solve the problem. A patient of 68 year old man in this case who suffered major tooth wear and maxillary posterior teeth loss was treated with elevation of vertical dimension of occlusion by maxillary removable dental prosthesis and mandibular fixed prosthesis.

• The Journal of Advanced Prosthodontics
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• v.1 no.3
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• pp.136-139
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• 2009

STATEMENT OF PROBLEM. Many dental clinicians are concerned about immediate loading of inserted implants. However, there have been few clinical studies surveying the success rates of immediate loading, based on Korean implant systems. PURPOSE. The aim of this study was to evaluate the outcome of immediate functional loading of the implant ($SinusQuick^{TM}$EB, Neobiotech Co., Seoul, Korea) in partially edentulous maxilla or mandible. MATERIAL AND METHODS. Total 15 implants were placed. Within 2 weeks after implant insertion, provisional implant-supported fixed partial dentures were delivered to the patients. Quantitatively, marginal bone loss was measured at the time of immediate loading, after 3-months of continued loading and at the last follow-up. The mean follow-up period was 4.8 months. RESULTS. Mean marginal bone loss from implant surgery to early loading, 3-months follow-up and last follow-up was $0.03\pm0.07$ mm, $0.16\pm0.17$ mm and $0.29\pm0.19$ mm. No implant failed up to 6 months after insertion, resulting in a 100% survival rate. CONCLUSION. Immediate loading exhibited high success rate in partial edentulism for up to 6 months. Well-controlled long term clinical studies with large sample size are necessary to confirm this finding.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.3
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• pp.207-215
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• 2017

Many factors should be considered for successful denture treatment at edentulous patients: support, retention, stability, occlusion, esthetics, etc. The patient who has severely absorbed residual ridges, however, treatments are challenging to satisfy those factors. The dentures that use anatomic artificial teeth show good mastication efficiency and esthetics but, can easily lose stability at absorbed ridges. On the contrary, the dentures that use non-anatomic artificial teeth perform better stability but, lower masticatory efficiency and esthetics at absorbed ridges. The lingualized occlusion, using both anatomic and non-anatomic teeth, introduced for compromise those of the pros and cons. At lingualized occlusion, buccal cusps of the teeth do not contact on centric relation. Therefore, direction of the occlusal force towards lingually, then stability of dentures increases. This case report shows the results of the treatment flat residual ridges using complete dentures with ligualized occlusion to increase dentures stability and satisfactory of the patient.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.3
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• pp.137-146
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• 2018

Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues. While for many years, tooth wear was a condition of little interest in daily clinical practice, nowadays this is changed. Tooth wear is becoming increasingly significant in maintaining the long-term health of the dentition. This becomes especially important when the dentition is kept relatively intact in the contemporary ageing population, and edentulism is decreasing. There is also evidence that the prevalence of tooth wear is growing. It is a natural consequence of the unidirectionality of tooth wear that it is frequently used as a means of individual age estimation. Tooth wear was very serious in ancient populations up to the medieval period. Tooth wear is thus studied in a wide variety of areas. The purpose of this paper is to summarize and analyze the many issues surrounding tooth wear through recent studies in various fields and to search for future research direction.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.3
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• pp.175-180
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• 2004

In this study, three treatment options to replace two posterior missing teeth were investigated using three dimensional finite element analysis: two wide(${\phi}5.0mm$) implants(the experimental model I), two standard(${\phi}3.75mm$) implants(the experimental model II), and three standard(${\phi}3.75mm$) implants(the experimental model III). Two kinds of load case were applied ; 1) perpendicular on occlusal surface(axial load), parallel on occlusal surface(lateral load). 2) perpendicular on occlusal surface(3mm lateral to central point). The results obtained from this study were as follows; value of Von-mises stress (equivalent stress) was smallest in the two wide implant among the three experimental models. It was reported that the diameter is the efficient factor than osseointegrated surface area.

• The Journal of Advanced Prosthodontics
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• v.8 no.6
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• pp.457-464
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• 2016

PURPOSE. The aim of this study was to determine whether two methods of documentation, print and electronic forms, for the assessment of patient-reported outcomes (PRO) in complete denture wearers provide comparable results. The study also quantified the time needed for filling the forms by each method. MATERIALS AND METHODS. Thirty participants enrolled in a university clinic answered two forms (a questionnaire for denture satisfaction and OHIP-EDENT). They provided answers with two application methods in a random order, with a one-month interval between them: (1) electronic forms on a tablet computer; and (2) print forms. The methods were compared in terms of mean results, correlation/agreement, internal consistency, and spent time. RESULTS. Mean results for both methods were similar for each denture satisfaction item (100-mm VAS) and OHIP-EDENT summary score. Both questionnaires presented good internal consistency regardless of the application method (Cronbach's ${\alpha}=0.86$ or higher). Correlation and agreement between the methods regarding specific items was at least moderate for the majority of cases. Mean time for the electronic and print forms were 9.2 and 8.5 minutes, respectively (paired t test, P=.06, non-significant). CONCLUSION. The electronic method is comparable to print forms for the assessment of important PRO of prosthetic treatment for edentulism, considering the results and time needed. Findings suggest the viability of replacing print forms with a tablet for applying the tested inventories in clinical trials.