Subgingival plaque removal at interdental sites using a low-abrasive air polishing powder

Background: The aim of the study was to test the efficacy of a novel low-abrasive air polishing powder in subgingival plaque removal at interdental sites during periodontal maintenance therapy (PMT). Methods: Using a split mouth design, subgingival plaque was removed in 23 PMT patients using a low abrasive powder using a standard air polishing unit (test) or curets (positive control). Before and immediately after treatment, subgingival plaque samples were taken from interdental sites with 3 to 5 mm probing depth (PD) at 2 test teeth and 2 positive control teeth. To evaluate the influence of sampling on the microflora, plaque samples were also taken twice at 2 teeth without therapy with PD of 3 to 5 mm (negative control). PMT treatment and plaque sampling were repeated 3 times at quarterly intervals. Anaerobe cultivation was utilized to assess the mean reduction of total colony forming units (CFU) immediately after treatment. Results: Test treatment resulted in a significantly greater reduction in subgingival bacterial counts (log 1.9 +/- 0.7) than positive control treatment (log 1.1 +/- 0.6) and subgingival plaque sampling alone (log 0.5 +/- 0.5; P<0.05). Differences between positive and negative control were not significant (P<0.05). Conclusion: The novel low-abrasive air polishing powder is superior to curets in removing subgingival plaque at interdental sites with up to 5 mm probing depth in PMT.