Relationship between 1-, 3-, and 6-Month Gingival Bleeding Outcomes

Abstract

Introduction: Results from systematic reviews and meta-analyses show generally consistent antigingivitis effects between 3- and 6-mo observation time points with twice-daily use of stannous fluoride (SnF2) dentifrice. However, the relationship between 1-, 3-, and 6-mo gingivitis responses has not been investigated. Methods: This pooled analysis was conducted to understand the relationship of 1-, 3-, and 6-mo gingival bleeding outcomes. Number of bleeding sites, derived from Löe-Silness Gingival Index (LSGI) or Gingival Bleeding Index, was identified as the primary end point of the analysis for the biological and clinical relevance. Randomized, double-blinded, controlled clinical studies meeting the following predefined selection criteria were identified: 1) published and unpublished gingivitis clinical trials conducted from 1995 to 2022 comparing efficacy of 0.454% SnF2 dentifrices to negative controls (sodium fluoride or sodium monofluorophosphate dentifrice) and 2) studies with a 3-mo assessment and at least a 1- or 6-mo assessment. Results: The search resulted in ten 6-mo and fourteen 3-mo studies meeting selection criteria. A mixed-effects model was performed on the pooled data to assess gingival bleeding outcomes across time. The bleeding efficacy significantly increased between months 1 and 3 (P < 0.0001) and plateaued between months 3 and 6 (P = 0.007), supporting the fact that bleeding reduction relative to control established by 1 mo will increase and be maintained through 3 and 6 mo (R2 = 0.857). In addition, gingival bleeding and gingivitis efficacy, as measured by LSGI, were found to be highly correlated (R2 = 0.874). Conclusion: A clear relationship has been demonstrated between 1-, 3-, and 6-mo gingival bleeding outcomes in gingivitis clinical studies comparing SnF2 dentifrice to negative control dentifrice. These findings have important implications to the dental practice and scientific research as antigingivitis efficacy evaluations can be observed as early as 1 mo and are consistent with those seen at 3 or 6 mo. Knowledge Transfer Statement: Outcomes from this investigation indicate that the clinical evaluation of antigingivitis efficacy at 1 mo is predictive of that at 3 and 6 mo, supporting studies of 1-mo duration as a viable method of knowledge acquisition. This more efficient, expedited research design has positive implications for patient care, clinical practice guidelines, protocols, and policies.