Augthun et al. examined the cultivability of mouse fibroblasts after cleansing machined or plasma-splayed surface implants carried on acrylic plates that had been contaminated with supragingival plaque from individuals. A plastic hand scaler and an air-abrasive system with sodium bicarbonate powder were employed in their study. A similar number of viable fibroblasts were observed after cleansing the implant with the air abrasive as the non-contaminated control implant. However, the number of viable cells was significantly reduced on the implant cleansed with the plastic scaler. This study had two drawbacks. First, they did not employ a quantitative analysis to evaluate the cleansing effect. Second, the SEM analysis used to evaluate the cleansing effect was too low (10- to 100-fold). In the present study, the presence of residual biofilms after instrumentation was determined using higher magnification SEM analysis (up to 5000-fold) and CFU counts. In this context, our findings may provide more accurate evidence than that demonstrated by the aforementioned study.

SEM analysis

Based on the results of the SEM qualitative analysis, gauze soaked in saline and the rotary stainless steel instrument consistently showed good cleansability on rough and machined surface implants compared with the other methods. Conversely, the Er:YAG laser showed inferior cleansability to all other methods especially on rough surface implants. The ultrasonic scaler and air abrasive exhibited fair to good cleansability on both surface implants. Generally, the cleansability of each method appeared to be better on machined surface implants than rough surface implants.