Objective: The surface roughness caused by four implant scaler s (Premier/Hawe-Neos, Advanced Implant Technologies, Hu-Friedy, and Nobel Biocare) on a titanium abutment was assessed in a standardized in vitro situation, and operators were asked to evaluate the clinical usefulness of each instrument. Method and materials: Twenty-four evaluators scored scanning electron micrographs of abutment surfaces scaled for 15 minutes with each instrument. Twelve operators used each instrument on at least three implant recall patients and scored each for ease of access; efficacy in deposit removal; overall convenience; distance reached subgingivally; scaling time per abutment; and overall preference. Results: The Advanced Implant Technologies scaler created a significantly rougher surface than all other instruments. The Premier/Hawe-Neos and Advanced Implant Technologies instruments were significantly preferred in most categories by the operators. There was no statistically significant difference in scaling time per abutment. Conclusion: The Premier/Hawe-Neos instrument combines operator acceptance with less damage to the abutments, and, of the instruments tested, is the scaler of choice.