RESUMO
The objective of this study is to compare retention capacity of mandibular implant-supported overdenture with all zirconia, zirconia-PEEK, and all PEEK telescopic attachments. Sixty acrylic resin models of mandible were used. Telescopic attachment system was made up of all zirconia, all PEEK, and zirconia-PEEK. Evaluation of retention force was done using universal testing machine. Obtained data were statistically evaluated. Highest initial force value was obtained with zirconia-PEEK group. All PEEK and zirconia-PEEK groups showed significantly decreased final retention values in comparison to their initial values. Zirconia can be regarded as the material of choice for telescopic crown, whereas polyetheretherketone and zirconia-PEEK telescopic crowns showed retention loss over a period of time.