Retention Loss of Locator Attachment System Different Retention Caps for Two Implant Retained Mandibular OverdentureMedhat

Abstract

Purpose. The objective of this invitro study was to evaluate gradual loss of retention at different time intervals between four different colour coded retentive caps of locator R-TX attachment system through 3000 cycles resembling 3years of attachment usage. Material and Methods. According to prosthetically driven implant placement, two implants were digitally planned and placed by 3D printed surgical stent in an epoxy model. Forty-eight mandibular complete dentures divided into four groups (12 dentures for each group) were constructed to compare Loss of retention between (12 pairs of locator R-TX each retention cap: zero retention, low retention, medium retention and regular retention), each was subjected to insertion and removal cycles resembling 3years of patient usage. Retention values at zero, one, two, three years were recorded using universal testing machine. Results: Locator R-TX medium &low retention showed no statistically significant retention values through three years while locator R-TX regular retention cap showed better retention values at zero, first, second year of use. Conclusion. Locator R-TX attachment systems low, medium, regular retention cap had no statistically significant different retention values at the end of third year of use while there were only statistically significant primary retention values. Clinical Implications. The importance of difference retention caps appears only in the start of over denture treatment until complete patient adaptation to over denture treatment10