Date of Graduation


Document Type


Degree Type



School of Dentistry



Committee Chair

Matthew Bryington

Committee Co-Chair

Michael Bagby

Committee Member

Brian Dye

Committee Member

Richard Jurevic


Objectives: To investigate the retentive capabilities of the LOCATOR (ZEST Anchors LLC, Escondido, CA USA) attachment and GPS (Implant Direct Sybron International, LLC, California, USA) dental implant attachment systems on parallel and divergent implants after cyclic wear.;Methods: An acrylic rod was cut into blocks representing 20 mandibular arches. Each block had either two LOCATOR or two GPS abutment analogs placed parallel or with 10 degrees of divergence. The associated housings were picked up in corresponding acrylic blocks with Ortho resin (Dentsply GAC, Islandia, NY USA). The black processing liners in each housing were replaced with a 1.5lb retentive liners. These blocks then had an eyebolt attached so each block could be attached to an Instron 5565 Universal Testing Machine (Instron, Northwood, MA USA). Each block with the retentive housings was repeatedly pulled from the block containing the abutment analogs and retentive force needed for dislodgement was measured at pull 1, 50, 100, 150, 200, 250, 300, 350, 400, 450 and 500.;Results: The data for each test sample was recorded and an ANOVA was preformed in JMP software (SAS Cary, NC USA). The type of attachments and the amount of pulls showed statistical significance however, the angle of the implants did not. Overall, the LOCATOR had 5.9N or 61% more retention then that GPS attachment.;Conclusion: The GPS attachment had greater initial retention but after 50 cycles of seating and unseating the retention was less than that of a LOCATOR attachment. After 500 cycles of seating and unseating the LOCATOR had 56.72% more retention on parallel implants and 40.21% more retention on angled implants.