Immediate Loading of Two Dental Implants, in Edentulous Mandibles, with Locator® Attachments or Dolder® Bars: First Results from a Prospective Randomized Clinical Study

Abstract

The study aims to evaluate survival and the incidence of complications for pairs of implants placed in the frontal area of edentulous mandibles and immediately loaded with either bar or Locator® (Zest Anchors LLC, Escondido, CA, USA) attachments. Forty-six patients (mean age 69.4 years; 73.9% male) with edentulous mandibles each received two immediately loaded implants in the interforaminal area of the symphysis. Immediately after implant placement, Dolder® bar (Sub-Tec Wirobond; BEGO Implant Systems GmbH & Co. KG, Bremen, Germany) or Locator® attachments, allocated randomly, were attached, and both clips and a framework were incorporated into the denture by the dental technician. The implants were loaded within 72 hours. During a mean observation period of 6 months (maximum 24 months, SD 0.43) eight implants in five patients were lost. Survival was 93.5% for the Locator® group and 89.1% for the bar group. Estimated cumulative survival after 1 year of function was 93.4% for the Locator® group and 87.1% for the bar group. During the observation period, 12 prosthetic complications required aftercare. No superstructure was lost or had to be remade for prosthetic reasons, but five dentures had to be removed or reworked after implant failure. Survival of the original dentures was, therefore, 95.7% for the Locator® group and 93.5% for the bar group. Within the limitations of this study, immediate loading of two implants in the edentulous mandible with either Locator® or bar attachments did hardly differ. Ease of repair and cleaning, in particular, might be arguments for choosing the single attachment system.