Comparative Evaluation of the Retention of Flexible and Acrylic Overdenture Retained by Different Number of Implants (In Vitro Study)

To determine the retention of overdenture with different number of implants, and to determine suitability between different denture base material with different numbers of implants. In this study we used 28 samples of overdentures which denture base of first group is flexible overdenture and other groups are acrylic overdenture, which supported by implant which 2 implants while the other is supported by 4 implants. And make the retention test for each group. The highest mean retention force was reached when the denture base material was acrylic and the number of implants was 4, and the second highest mean retention force was when the material was flexible overdenture, and the number of implants was also 4. While the lowest retention force detects in flexible overdenture supported by 2 implants. We conclude that acrylic overdenture supported by 4 implants is the best retention than others.