Imeri, Alfredo Montes2010-03-292010-03-292009-12https://hdl.handle.net/11299/59890University of Minnesota M.S. thesis. December 2009. Major: Dentistry. Advisor: James R. Holtan. 1 computer file (PDF); vi, 31 pages.STATEMENT OF PROBLEM. Successful implant treatment requires a favorable biological response of living tissues to a foreign material. Even with a favorable pre-surgical evaluation, negative changes such as crestal bone loss can occur after the implant is placed, which can result in an esthetic failure. Controlling crestal bone loss around an implant placed adjacent to a natural tooth or to another implant represents an important challenge for present day prosthodontics. Guidelines on the distance between an implant and a natural tooth or another implant have been published as being an important factor in proximal bone preservation. PURPOSE. The purpose of this study was to retrospectively evaluate pre-treatment and post-treatment proximal bone levels of a single tooth, plateau-designed, press fit implants (Bicon®) utilizing a locking tapered, implant to abutment connection adjacent to a natural teeth and to a plateau design Bicon® implants. The bone levels were evaluated separately for those implants that were closer to a natural tooth or to another implant than the recommended guidelines. Bone levels were also measured on mesial and distal surfaces of all implants as well as the crestal bone levels between 2 implants. The relationship between implant spacing and crestal bone levels was to be determined. MATERIAL AND METHODS. A retrospective cohort study was designed to evaluate pre-treatment and post-treatment proximal bone levels of a single tooth, plateau-designed, press fit implants (Bicon®) utilizing a locking tapered, implant to abutment connection adjacent to a natural teeth and to a plateau design Bicon® implants. The cohort was derived from patients who received 1 or more single tooth, plateau-designed, press fit implants between 1995 and 2005. One hundred and sixty-nine implants with 338 proximal surfaces were included in this study. Of the 338 proximal surfaces, 120 were adjacent to a natural tooth, 192 were adjacent to an implant, and the remaining 26 surfaces were adjacent to an edentulous area. The mean follow-up time was 4 ± 2.3 years. Bone levels and changes in bone levels over time were determined by direct measurement of non-standardized digital periapical radiographs. All measurements were made by using a software measuring tool (DIGORA; Soredex, Tuusula, Finland) at ×3.0 magnification. Student T-tests were used to evaluate the statistical significance between pre-treatment and post-treatment proximal bone levels of natural teeth adjacent to implants. Level of significance was set to alpha 0.05. Descriptive statistics were used to report bone levels on implants adjacent to a natural tooth, another implant, or an edentulous area, as well as the crestal bone levels between 2 implants. RESULTS. There was no significant difference (P=0.25) between pre-treatment proximal bone levels and post-treatment proximal bone levels on a single tooth, plateau-designed, press fit implants (Bicon®) utilizing a locking tapered, implant to abutment connection adjacent to a natural teeth and plateau design Bicon® implants. CONCLUSIONS. Bone levels on implant surfaces adjacent to another implant and bone levels on natural teeth adjacent to implants can be expected to remain unchanged post-treatment when a single tooth, plateau-designed, press fit implant is placed closer than the recommended distance away from the natural tooth or to another implant.en-USImplantBonesProsthodonticsPlateau design Bicon® implantsDentistryThesis or Dissertation