Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Prosthodontics

This study was carried out to evaluate the retentive capacity of two types of attachments used to retain single implant supported mandibular overdenture using universal testing machine after insertion and removal cycles that was done by chewing simulator. The two attachments used in this study were ball and socket and CM LOC. An epoxy model of completely edentulous mandible was constructed and prepared to receive single implant in the midline area. An overdenture was constructed, and a steel rod was fixed to the denture using auto polymerized acrylic resin at the denture geometric center. With each type of attachment, the pickup procedure consisted of attaching one part of the attachment to the fitting surface of the denture with self-cure acrylic resin, while the other part was screwed to the implant. The aim of this study was to subject the attachments to mechanical aging using a chewing simulator and throughout the cycles the retention was measured for both attachments using a universal testing machine. Using the ROBOTA chewing simulator the overdenture was subjected to insertion and removal cycles. These cycles was performed in wet environment simulating the saliva (Isotonic 0.9% sodium chloride solution at 22{u00B0}C). A weight of 5 kg, which is comparable to 49 N of chewing force was exerted, with a vertical up and down movements of the upper compartmen

Issued also as CD