A randomized controlled trial on the efficacy of fluoride varnish in preventing dental caries of Sjögren's syndrome patients

Abstract

OBJECTIVES: The primary objective of this study was to evaluate the efficacy of fluoride varnish in caries prevention and arrest on coronal and root surfaces of teeth over a 24-month period in Chinese Sjögren’s syndrome (SS) patients. Secondary objective was to investigate the effect of fluoride varnish on oral microorganism (Candida and lactobacilli).

METHODS: This study was a randomized, double-blind, placebo-controlled clinical trial. A total of 85 SS patients participated in this study. They were randomly assigned to two groups to receive either fluoride varnish or placebo gel quarterly. Dental examination, and assessment of the sicca symptoms, oral hygiene, salivary flow / pH / buffering capacity and oral microbiological profiles were carried out at the baseline, 12-month and 24-month visits.

RESULTS: Seventy-eight patients (92%) completed the 24-month trial. At the 24-month visit, no statistically significant differences (Mann-Whitney test, P > 0.05) were found between the fluoride and the placebo groups regarding their mean numbers of coronal surfaces with new enamel caries lesions (fluoride: 1.6; placebo: 1.6), arrested caries lesions (fluoride: 0.6; placebo: 0.7), and also root surface caries lesions (fluoride: 0.3; placebo: 0.1). SS patients who had received application of fluoride varnish were significantly less likely to develop dentin caries in coronal surfaces over the 24-month study period (P = 0.035). The mean numbers of coronal surfaces with new dentin caries lesions found at the 24-month visit in the fluoride and placebo groups were 1.4 and 2.7, respectively (Mann-Whitney test, P > 0.05). The caries prevented fraction of fluoride varnish for coronal dentin caries was 33.3%.

No significant differences in the mean counts of Candida and lactobacilli between fluoride and placebo groups were detected (Mann-Whitney test, P > 0.05).

Results of the logistic regression analysis showed that SS patients who had high baseline DMFS scores (P = 0.050), harbored more species of Candida in the dental plaque samples (P = 0.019), or had low pH of unstimulated whole saliva (P = 0.005) were significantly more likely to develop dentin caries in coronal surfaces over the 24-month study period.

CONCLUSIONS: Fluoride varnish may be efficacious in preventing coronal dentin caries in Chinese patients with SS. However, it may not be efficacious in preventing root caries and has no effect on oral microorganism.