Biomechanical Research For Ti-Alloy Attachment Overdenture

Retraining and reducing terminal teeth to use as overdenture abutment is the line of defense before rendering the jaw completely edentulous. To prevent alveolar bone resorption, provide better load transmission of prostheses, and maintain the sensory feedback of periodontal receptors, roots were maintained in the alveolar ridge. Retention and stability of overdenture are improved by the use of attachment fabricated on roots. Recent decade, the treatment which two or, four implants were placed in an edentulous patient to support an overdenture is moreaffectivee and safety. Overdenture supported with implants has less difficulty to operate, lower to cost and the mount of resorption of the edentulous bone was more pronounced compared with minimal changes when fixed prostheses were supported by implants. Therefore, it was suggested that overdenture supported by implants should be suitable for older edentulous patientsIt is basic for overdenture to remain roots or implants in alveolar bone. Except for caries, periodontal breakdown and edentulous problem, fractures of roots or posts are innegligible causes of failure when-roots are maintained overdenture support; whereas implants are lost because of bone loss and increased mobility. With CAD and FEA, the present study investigated the effects of the shape and structure designs of attachment posts on the stress distribution in dentin, and we further analyzed the stress distribution of the supporting tissue of overdenture supported by roots or implants with a three dimensional finite element methods when various attachment retentive apparatus or various bite forces were applied. Finally the study also investigated the feasibility of bar attachment framework fabricated with titanium casting. Effect of stud attachment post design on dentine stress distribution1. The change of the dentin stress value is parabola relationship with the changes of post diameter. With the optimum calculation of the finite element analysis, the optimal diameter of attachment post was attained 1.55mm The...