Comparison of subgingival plaque removal using hand curettes, magnetostrictive ultrasonic scalers and air polishing devices with and without NaHCO3 abrasive powder: an ex vivo study

Background and aims. One important treatment objective of periodontal therapy is the removal of bacterial deposits and the arrest of disease progression. The aim of the present study was to compare subgingival plaque removal using hand curettes, magnetostrictive ultrasonic scalers and air-polishing devices (APD) with and without NaHCO3 abrasive powder. Materials and methods. In this controlled randomized clinical trial, all surfaces of 60 single-rooted hopeless teeth with untreated periodontitis were treated either by hand curettes, magnetostrictive ultrasonic scalers or APD with or without NaHCO3 abrasive powder. The teeth were extracted and stained in methylene blue in water solution. Digital images were captured under a microscope and depth of plaque removal was measured with image processing software. ANOVA and correlation tests were applied to data. Results. The mean comparison showed that using APD with water alone failed to achieve adequate plaque removal. Subgingival plaque removal in the lingual surface was significantly lower in all investigated instruments (P < 0.001). The mean cleansing depths of curettes, ultrasonic scalers and APD with NaHCO3 powder were 4.6, 6.0 and 4.2 mm, respectively. Conclusion. The effectiveness of different instruments is not identical for different sites. Therefore, the efficiency of these instruments should be adjusted for various clinical applications.