Clinical and microbiologic results 12 months after scaling and root planing with different irrigation solutions in patients with moderate chronic periodontitis: a pilot randomized trial

Background: The aim of this study is to determine in a randomized trial the impact on treatment outcome after 12 months of different subgingival irrigation solutions during scaling and root planing (SRP). Methods: Fifty‐one adult volunteers with generalized chronic periodontitis were treated by full‐mouth SRP using 0.9% sodium chloride, 0.12% chlorhexidine digluconate, or 7.5% povidone–iodine for subgingival irrigation during SRP. Before SRP and after 3 and 12 months, probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were recorded. Subgingival plaque samples were analyzed for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Results: PD, CAL, and BOP were significantly improved in all groups after 12 months (P <0.001 to P = 0.044). No significant differences were seen among the groups for all sites and sites with 4 to 6 mm PD at 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 = 0.045 and P = 0.002) 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. Conclusions: No differences were seen among the groups in the clinical results after 12 months. Regarding the microbiologic results, a slight benefit seemed to derive from the use of povidone–iodine.