Greater prior fluoride intensity decreases caries in high risk veterans

Objectives:   The purpose of this study was to examine the effectiveness of multiple applications and multiple modalities of topical fluoride in reducing caries among a high risk population of adults with multiple chronic conditions.

Methods:   High caries risk adults were defined as those receiving two restorations in one year which was defined as the index year. Based on this definition, 140,114 adults with multiple chronic conditions and high caries risk were included in our study.  A multiple logistic regression model was fit with adjustment for all putative risk factors to determine the effect of (1) the number of applications and number of modalities of topical fluoride given to subjects during the year prior to inclusion in the study, (2) number of applications and number of modalities of topical fluoride given to subjects following the first restoration in the index year, and (3) number of applications and number of modalities of topical fluoride given to subjects following the last restoration in the index year.

Results:   The following table shows odds ratios and 95% confidence intervals for risk of a new restoration based on number of applications and number of modalities of topical fluoride according to time of application.

More modes/exposures of fluoride in the year prior to inclusion were associated with a decreased risk of a new restoration.  In contrast, more modes/exposures of fluoride during the index year were associated with an increased risk of a new restoration.  Increasing modes/exposures of fluoride following index year were also associated with increasing risk of a new restoration.

Conclusion:   Increased modalities/applications of fluoride after restoration placement may represent high caries risk patients in contrast to showing effectiveness, whereas increased modalities/applications of fluoride provided prior to restoration placement likely represents effectiveness in caries prevention.