Inhibition of Secondary Caries Lesion Progression Using Fluoride Varnish

Abstract

The purpose of this study was to determine the efficacy of fluoride varnish (FV) in inhibiting progression of secondary caries (SC). In a first experiment, human teeth, restored either with amalgam or resin composite, were exposed for 4 days to a microbial caries model. Half of each specimen was then painted with an acid-resistant nail varnish to maintain the baseline SC lesion. Specimens were then either treated with a FV (removed after 24 h) or not treated (control groups) prior to being exposed for 4 more days to the caries model. A second experiment was conducted to compare the effect that the varnish (with and without fluoride) had on SC development around amalgam. Confocal laser scanning microscopy data from these experiments suggested that the application of a FV to early, active SC lesions significantly slowed down their progression. Furthermore, the application of a placebo varnish showed a trend towards slowing down lesion progression, suggesting that the effect of FV on SC is not only due to its fluoride release.

In Vitro-evaluation of Secondary Caries Formation around Restoration

“…Control of carious lesions is mainly related to the presence of fluoride in the oral cavity, and may not be considered as directly dependent on the amount incorporated by the tooth 6,17) , since the main mechanism of action of fluoride is dynamic, inhibiting demineralization and enhancing remineralization 4,19) . Therefore, the constant presence of fluoride in the oral cavity, in saliva or oral fluids, dental plaque and enamel, may control or even inhibit the appearance of secondary carious lesions, as well as lead to arrest of existing lesions, preventing progression of incipient lesions to formation of cavity 6,22) .…”

“…Therefore, the constant presence of fluoride in the oral cavity, in saliva or oral fluids, dental plaque and enamel, may control or even inhibit the appearance of secondary carious lesions, as well as lead to arrest of existing lesions, preventing progression of incipient lesions to formation of cavity 6,22) . It should be noted that the model of caries development adopted in this in vitro study is similar to that advocated by Featherstone et al 4) , which assumes a correlation with the onset and progression of carious lesions in vivo where there is a high risk of caries.…”

“…Fluoridated materials offer a potential source of this element, which would expand the spectrum of prevention in restorative dentistry. The use of fluoride to demineralize and remineralize early enamel carious lesions directly interferes with the evolution of caries 1,6,19) . It is accepted that part of the fluoride present in restorative materials may be directly released onto areas of risk, such as restoration margins, where secondary caries may develop 1,19,22) .…”

“…in restorative dentistry 1,6) . Fractures, insufficient marginal adaptation and excess restorative material, failures that are frequently observed in restorations, result in microleakage.…”

Evaluation of Several Techniques for the Detection of Secondary Caries Adjacent to Amalgam Restorations

“…Confocal laser scanning microscopy (CLSM) presents several advantages such as not requiring a thin section nor involving radiation and can be done in shorter time [Fontana et al, 1996]. Several studies have demonstrated that CLSM is a valid technique to quantify mineral changes in smooth surface caries lesion and secondary caries lesion using area measurement [Fontana et al, 1996[Fontana et al, , 2002Gonzá lez-Cabezas et al, 1998]. In this current investigation, the severity of secondary caries lesions was determined with the CLSM technique to measure the area of fluorescence.…”