Adjunctive Povidone-Iodine Improves Bleeding Outcomes in Step 2 of Periodontal Therapy: A Retrospective Cohort Study.

Abstract

<h4>Background</h4>This retrospective cohort study evaluated the effects of adjunctive povidone-iodine (PVP-I), full-mouth disinfection (FMD), and conventional full-mouth scaling (FMS) following Step 2 of periodontal therapy on clinical outcomes.<h4>Methods</h4>Patient records from the Department of Conservative Dentistry, University Hospital Tubingen (2004-2016), with complete periodontal data before (T0) and after Step 2 of periodontal therapy (T1), were analyzed. The influence of treatment modality, baseline bleeding on probing (BOP%), proportion of sites with probing pocket depth (PPD) ≥ 5 mm, age, smoking, diabetes, and re-evaluation interval on changes in BOP and PPD, as well as on the clinical endpoints <i>BOP ≤ 20%</i> and <i>≤ 4 sites with PPD ≥ 5 mm</i>, was assessed using multivariable regression.<h4>Results</h4>A total of 227 patients were included (52% female; mean ± SD age: 56.5 ± 11.2 years): 96 FMS, 93 FMD, and 38 PVP-I. Adjunctive PVP-I led to a significantly greater reduction in BOP compared with both FMD and FMS and substantially increased the likelihood of achieving <i>BOP ≤ 20%</i> (adjusted OR = 11.5; p = 0.03), independent of baseline inflammation and re-evaluation period. For the pocket-related endpoint (<i>≤ 4 sites with PPD ≥ 5 mm</i>), regression models were unstable due to the small number of successful cases; baseline PPD % remained the only consistent predictor.<h4>Conclusion</h4>Adjunctive PVP-I use was significantly associated with improved bleeding-related outcomes after Step 2 of periodontal therapy, whereas no additional benefit was observed for deep-pocket reduction. PVP-I may therefore enhance the resolution of gingival inflammation but does not substantially affect pocket closure beyond conventional mechanical therapy.