This study compared the effects of metallic, nonmetallic, and sonic instrumentation on titanium abutment surfaces in vitro. Designated test surfaces in each of seven abutments were instrumented either for 25 strokes or 30 seconds, and for 50 strokes or 5 minutes. One abutment served as an untreated control. Scanning electron microscopy photomicrographs were coded and scored by five investigators and designated as smooth (comparable to control) (0), slightly roughened (1), moderately roughened (2), or severely roughened (3). Based on this investigation, the increasing order of surface alteration for each instrumentation was as follows: Implacare Implant Support Steri-Oss Dynatip Columbia 13/14 Sonic scaler Implarette scaler. The Implacare and Implant Support nonmetallic (plastic) scalers appear to be the instruments of choice for debridement of titanium abutment surfaces if preservation of surface integrity is the primary objective. Schlagwörter: implant, instrumentation, maintenance, surface roughness