Interdental subgingival plaque removal: A comparison between hand instruments, ultrasonic scaler and Air–powder polishing devices with and without abrasive powder Dr. R. Pourabbas *- Dr. A. Mahmoudpour ** - Dr. MT. Chitsazi ***, Dr. S. Somi **** *Associate Professor of Periodontics Dept., Faculty of Dentistry, Tabriz University of Medical Sciences. **Assistant Professor of Drug Applied Research Center, Tabriz University of Medical Sciences. *** Assistant Professor of Periodontics Dept., Faculty of Dentistry, Tabriz University of Medical Sciences. **** Dentist. Abstract Background and Aim: The aim of this study was to compare the efficacy of air-polishing devices (APDs) with hand instruments and ultrasonic scalers when used for interdental subgingival plaque removal. Likewise, the effectiveness of APD with and without abrasive powder was evaluated. Materials and Methods: A total of sixty single-rooted teeth were treated in fifteen periodontal patients with 4-6mm mesial probing depth (PD). The selected procedures were hand instruments (Gracey curettes), ultra sonic scalar, APD without powder and APD with powder. Before and immediately after the treatment procedures, subgingival plaque samples were collected from the mesial aspects of these teeth. The anaerobe cultivation method was utilized to assess the mean reduction of total colony forming units (CFU) immediately after treatment. Results: Subgingival microorganisms were significantly reduced in all methods. The mean CFU differences between before and after treatments were significant (P<0.001) for all procedures. However, no significant difference was observed in the effectiveness of various methods. On average, all methods were able to reduce subgingival microorganisms by 92%. There was also a positive correlation between the colony counts before and after treatments (r= 0.52). Conclusion: Using APD is as effective as hand instruments and ultrasonic scalers for interdental subgingival plaque removal in cases with up to 6mm probing depth. The use of abrasive powder does not enhance the effectiveness of APD in subgingival plaque removal. Key words: Comparative study - Scaling / polishing – Air - powder polishing device - Subgingival bacterial plaque - Ultrasonic scaler - Hand instrument Correspondence Author: Periodontics Dept., Faculty of Dentistry, Tabriz University of Medical Sciences. e.mail:Pourabbas@tbzmed.ac.ir | 
