RCT comparing minimally with moderately rough implants. Part 2: microbial observations

Abstract

Most current implants have a moderately rough surface (compared with older minimally rough "turned" implants) to facilitate osseointegration. This randomized controlled trial (RCT), with split-mouth design, examined whether this increased surface roughness influenced the initial subgingival plaque formation. Ten fully edentulous and eight partially edentulous patients, all with a history of severe periodontitis, received 4-6 implants (mandible or maxilla). Per jaw, both minimally (turned) and moderately rough (TiUnite) implants (MKIII; Nobel Biocare) were alternated. Also, the healing and final abutments had similar surface characteristics. Subgingival biofilm formation was followed up for 1 year, and samples were analyzed by culture technique, qPCR and checkerboard Over the entire period, no statistically significant differences could be detected in subgingival microbiota between the minimally and moderately rough surfaces. In partially edentulous patients, the biofilm matured to a higher concentration of pathogens when compared with fully edentulous patients. The subgingival implant composition and concentration in partially edentulous patients were comparable to the subgingival microbiota along teeth. The roughness of the more modern implants did not influence the biofilm formation during the first year of implant loading.