A study that investigated the impact on treatment outcome after 12 months of different subgingival irrigation solutions during scaling and root planing (SRP) was recently published in the Journal of Periodontology by Dr. Carlos Krück et al. The randomized trial involved 51 adult volunteers with generalized chronic periodontitis who were treated by full-mouth SRP using the following subgingival irrigants during SRP: 0.9% sodium chloride, 0.12% chlorhexidine digluconate, or 7.5% povidone-iodine. Probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were recorded prior to SRP, after 3 months, and after 12 months. Subgingival plaque samples were analyzed for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. The study found that PD, CAL, and BOP were significantly improved in all groups after 12 months (P < .001 to P = .044). No significant differences were seen between the groups for all sites and sites with 4 to 6 mm PD at the baseline. The povidone-iodine group had the highest clinical improvements. The counts of A actinomycetemcomitans and P gingivalis were significantly reduced after 12 months (P = .045, P = .002) using povidone-iodine. Significant differences between the groups were seen after 3 months for A actinomycetemcomitans and P gingivalis, and after 12 months for T forsythia. The study concludes that no differences were seen between the groups in the clinical results after 12 months, although regarding the microbiological results, a slight benefit seems to derive from the use of povidone-iodine.
