Method: In an experimental study in dummy head, a sonic (AIR), an ultrasonic device (TIG) and double sharpened special curettes’ (GRA) were utilize by 12 operators (8 EO/ 4 LO) to remove biofilm. The time required for treatment was measured. Afterwards the percentage of residual biofilm and the weight loss for each tooth that was scaled was determined.
Result: All operators needed 3.14±1.16min/tooth for debridement regardless of the used instrument. The sonic scaler AIR showed the highest biofilm removal (21.45±21.31%) (p<0.001) compared to the special curettes’ GRA (28.21±19.96%) and the ultrasonic device TIG (32.48±22.45%). More and less experienced operators revealed a significant difference only in the using of AIR (p=0.012). Molars in the lower jaw (46.17%) presented nearly 20% more residual biofilm after scaling related to the mean over all (27.38%). Both treatment groups removed more hard tooth structure with hand instruments (p<0.001) than with powered device systems (p=0.280) (GRA: 12.7±4.7mg; AIR 7.5±3.7mg; TIG 7.6±8.3mg). However the LO works more aggressive and showed a higher weight loss after scaling (p=0.004).
Conclusion: Hand instruments showed constant results for all operators, but a high loss of tooth substance. Sonic scaler allowed a higher biofilm removal over all as well as a lower loss of dental hard tissue. Due to training, less experienced operators reached similar results in the effectiveness as experienced operators regardless of the instrument used, but with more severe side effects.