الفهرس | Only 14 pages are availabe for public view |
Abstract Polymethyl methacrylate (PMMA) has been the most popular material used for denture fabrication since its introduction in 1937, it has several advantages. The traditional use of the metal clasp materials as cobalt chromium Co-Cr hampers esthetics, increases the weight of the prosthesis and leads to allergic reactions. All these problems have led to the introduction of thermoplastic resin materials. More recently, the thermoplastic monomer free semi-rigid microcrystalline polymer (karadent by TCS, INC, USA) is introduced to the market and became a good alternative framework material for removable denture construction. Twelve mandibular bilateral partially edentulous male patients (Class I Kennedy classification) were selected for this study and randomly divided into two equal groups, control group received a mandibular removable partial denture (RPD) constructed of Cobalt Chromium and test group received a mandibular removablepartial denture (RPD) constructed of the thermoplastic semi-rigid microcrystalline polymer material (karadent). Clinical evaluation were carried out for every patient at insertion, 6, and 12 months by recording the gingival index and pocket depth scores at mesiobuccal, midbuccal, distobuccal, mesio-lingual, midlingual and distolingual of each abutment tooth. The average of these records was calculated and recorded, the mean was calculated and then the patient recalled for reassessment of oral hygiene and gingival health. Summary and Conclusion (84) Radiographic evaluation were carried out for every patient at insertion 6, and 12 month by making radiographic records to evaluate Changes in bone height and width of the residual ridge, carried using CBCT radiography. The mean of changes were collected, tabulated, and statistically analyzed. The following results were obtained: 1. Bony changes of the supporting structures was greater in Karadent than in Vitallium in both sides of theridge. 2. Pocket depth scores were greater in Vitallium than in Karadent in distal abutments of both sides. 3. Gingival index scores were greater in Vitallium than in Karadent in distal abutments of both sides. Conclusion RPD effect on the supporting structures of Kennedy class I cases is an ongoing process, controllable rather than stoppable by addition of distal implants and alteration of materials of RPD components. Within the limitations of this study, it was concluded that: 1) The use of karadent with its superior properties, is better accepted by the patients, regarding esthetics. 2) The metallic partial denture appears to make less adverse effect on the supporting bone in Kennedy Class I partially edentulous patients than semi rigid thermoplastic ones ( karadent ). 3) The abutment teeth reacted more favorably and offers superior results regarding gingival condition around the terminal abutment with the use of the thermoplastic semi-rigid microcrystalline polymer (karadent). Summary and Conclusion (85) Recommendation The thermoplastic PRD lacks an important factor of the traditional PRD, in particular, a rigid framework. Therefore, the recommendation of this study is to reinforce it with metal (hybrid design) to provide the PRD with sufficient rigidity with a metallic major connector and sufficient support with metallic rests and to compare its effect on supporting structure of distally extended cases with cobalt chromium RPDs |