Objective: The aim of this study is to assess the surface roughness of the implant-retained mandibular bar overdenture (BOD) and the implant-retained mandibular ball joint overdenture (BJOD) in jaw and its relation with the adhesion of molds and yeasts and mesophyll aerobe, in time 30 and 180 days in mouth. Materials and Methods: Five-systems titanium bar CARES® and synOcta® Straumann® Dental Implant System, Holding AG Inc., Basel, Switzerland (BOD), and five-systems joint ball Klockner® Implant System; Soadco Inc., Escaldes-Engordany; Andorra (BJOD), were used in two parallel groups of five participants, in an essay to simple blind person. To 30 and 180 days, the overdentures were withdrawn and evaluated the Ra: um. SJ-301® Mitutoyo Corporation Inc., Kanagawa, Japan, and the adhesion of microorganisms (colony-forming unit/ml). Results: The results were as follows: the Ra: Um (30th and 180th): BOD, 0.965-1.351; BJOD, 1.325-2.384. Adhesion: Molds and yeasts, BOD, 2.6 × 102 and 4.6 × 103; BJOD, 3.0 × 102 and 5.3 × 104. Adhesion: Mesophyll aerobe, BOD, 3.8 × 106 and 5.8 × 106; BJOD, 4.3 × 106 and 7.1 × 107. Conclusions: At 30 days (P = 0.489), there were no differences in BOD and BJOD for adhesion of molds and yeasts and mesophyll aerobe between both overdentures. At 180 days (P = 0.723), there were differences in the adhesion of mold and yeast and mesophyll aerobe, being greater in BJOD.