Mandibular implant-supported overdenture using CAD-CAM Konus type attachment: A case report / 대한치과보철학회지

In edentulous mandible, implant supported overdenture was considered as a first treatment option. Konus type attachment supplies rigid support and cross arch stabilization so that more favorable force transmission and distribution can be attained. In the dentistry, computer aided design-computer aided manufacturing (CAD-CAM) system makes it possible to fabricate restorations with high precision and effectiveness. Recently, Palladium-silver (Pd-Ag) alloy which is millable has been developed. This article presents that application of CAD-CAM Konus type attachment can be provide satisfactory stability and function on four-implant supported mandibular overdenture.

A Study on the Stress Distribution of Tooth/Implant Connected with Konus Telescope Denture Using 3-Dimensional Finite Element Method / 대한치과보철학회지

PURPOSE: For decades dental implants have been used widely in the field of prosthetic dentistry. However there is confusion when establishing treatment plans in cases where some teeth are remained but an insufficient number of implants can be used due to limited anatomical status and ecomomical problems. Many clinicians have tried to connect natural teeth and implants, and it still has controversy. But, there have been few studies on mechanical analysis of connecting natural teeth and implants with konus telescopic removable partial dentures. The purpose of this study was to analyze the stress distribution of prosthesis, abutment and alveolar bone when teeth and implants were connected with the konus telescopic denture, by means of 3-dimensional finite element analysis. MATERIAL AND METHODS: The assumption of this study was that there were 2 mandibular canine (11 mm in length, 4 mm in diameter) and 2 implants(10 mm in length, 4 mm in diameter) which are located in the second premolar region. The mandible, teeth, implants, abutments, and connectors are modeled, and analyzed with the commercial software, ANSYS Version 8.1(Swanson, Inc., USA). The control group used implants instead of natural teeth. 21038 elements, 23544 nodes were used in experimental group and 107595 elements, 21963 nodes were used in control group, Stress distribution was evaluated under 150 N vertical load on 3 experimental conditions - between teeth and implants (Load case 1), posterior to implants (Load case 2), between natural teeth (Load case 3). RESULTS: 1. In all load cases, higher von mises stress value was observed in the experimental group. 2. Maximum von miss stress observed in all load cases and all locations were as follows ; a. 929.44 Mpa in the experimental group, 640.044 Mpa in the control group in outer crown and connector - The experimental group showed 1.45 times high value compared with the control group. b. 145,051 Mpa in the experimental group, 142.338 Mpa in the control group in abutment - The experimental group showed 1.02times high value compared with the control group. c. 32.489 Mpa in the experimental group, 25.765 Mpa in the control group in alveolar bone - The experimental group showed 1.26times higher value compared with the control group. 3. All maximum von mises stress was observed in load case 2, and maxim von mises stress in alveolar bone was 32.489 Mpa at which implant failure cannot occur. 4. If maximum von mises stress is compared between two groups, the value of the experimental group is 1.02 times higher than the control group in abutment, 1.26 times higher than the control group in alveolar bone. CONCLUSION: If natural teeth and implants are connected with the konus telescopic denture, maximum stress will be similar in abutment, 1.26 times higher in alveolar bone than the control group. With this result, there may be possible to make to avoid konus telescopic dentures where natural teeth and implants exist together.

Double crown retained removable partial denture -4 years in retrospect / 대한치과보철학회지

STATMENT OF PROBLEM: Little in known about the importance of selection of various double crowns as retainer in determining the outcome of treatment with double crown retained removable partial denture. Purpose : To obtain information about the effects and the results of this treatment modality. MATERIAL AND METHODS: This study describes 61 double crown retained removable partial dentures worn by 51 patients from Samsung Medical Center, Seoul a time ranging between 6 and 48 months and evaluate occlusal contacts on the denture teeth, denture movement, incidence of denture relining, denture retention, fracture of dentures and abutments, hygiene, residual ridge inflammatory changes, number of lost abutments, interruption of denture use. RESULTS: One tenth of all the restorations were relined. Restorations in 21 arches fractured repeatedly for various reasons. There was no apparent interrelationship between fractures and the five groups. CONCLUSION: Good prognoses of removable partial dentures were shown in all groups(Kennedy Classes I, II, III, combination and few remaining abutment).

Several Methods Of Fabrications Of Inner Crown And Outer Crown In Construction Of Konus Denture / 대한치과보철학회지

The purpose of this article is the consolidation of several methods in fabrication of Konus denture.It is different Konus denture from traditional Clasped removable partial denture in the procedures of construction.There are multiple procedures of fabrications of inner and outer crowns in the construction of Konus denture.It is important to fabricate the inner crown,the outer crown and the denture framework in construction of Konus denture.Each procedure should be performed exactly.However,there are many procedures in fabrications of them,and thus,the operator and technician bear trial and error.This article consolidate the multiple methods of fabrications of components of Konus denture.The first method is completion of inner crown,outer crown and denture after one impression taking.The second method is the procedures of cementation of inner crown,impression taking of edentulous area,and completion of outer crown and denture.The third method is the procedures of pick up impression taking of inner crown and completion of outer crown and denture on the inner crown of working cast.Each method is acceptable,but operator and technician should be accustomed with their own systemic procedures and minimize the errors in the construction of denture.