PubMed ID (PMID): 22146255Pages 557-561, Language: EnglishFreitas-Júnior, Amilcar C. / Bonfante, Estevam A. / Martins, Leandro M. / Silva, Nelson R. F. A. / Marotta, Leonard / Coelho, Paulo G.The reliability and failure modes of molar crowns supported by three different implant-supported designs were tested according to the following groups: group 1, one standard-diameter implant (3.75 mm); group 2, one narrow-diameter implant (3 mm); and group 3, two narrow-diameter implants (3 mm). Loads were applied as mouth-motion cycles using a step-stress accelerated life-testing method. ß values for groups 1 and 3 (1.57 and 2.48, respectively) indicated that fatigue accelerated the failure of both groups, but not for group 2 (0.39). Abutment screw failure was the chief failure mode. Strength and reliability were significantly higher for groups 1 and 3 compared to group 2.
