Effectiveness of plant-derived proanthocyanidins on demineralization on enamel and dentin under artificial cariogenic challenge
. J Appl Oral Sci.
infLuence of eR:yAG LAseR on micRoHARdness of enAmeL AdJAcent to RestoRAtions submitted to cARioGenic cHALLenGe
Moreover, these verying results may be explained by the different methodologies used for simulated cariogenic challenge
; however, pH-cycling is a proven method for producing artificial carious lesions in enamel [ten Cate and Djuisters, 1982].
(7) Among these methods, F varnishes as a tooth surface coverage seems to be a simple and effective way to protect at-risk enamel against acid (8) provided by bacterial metabolism during a cariogenic challenge
. In addition, F varnishes do not require patient's compliance.
, but simulating a low cariogenic challenge
. The specimens in each group were initially immersed in a demineralising solution (2.0 mM calcium, 2.0 mM phosphate in 75 mM acetate buffer, pH 4.3) for three hours at 37[degrees]c, then washed for one minute in de-ionised water, blot dried and immersed in a remineralising solution (1.5 mM calcium, 0.9 mM phosphate, 150 mM of KCl in 0.1M TRIS buffer, pH 7.0) for 21 hours at 37[degrees]c.
After the simulated cariogenic challenge
, the specimens proceeded to the final AFM analyses to obtain the roughness (Ra) and surface topography records by performing three distinct readouts in the delimited center of each specimen, under similar conditions to those in the initial analysis.
Thus, it is relevant to consider that when the affected dentine layer is kept on the pulpal wall of the cavity, chemical mechanism of bonding and fluoride release can be beneficial to resistance against degradation [De Munck et al., 2005], as well to as facing cariogenic challenge
. In this sense, it seems plausible to investigate the behaviour of restorations in caries-affected dentine, made with Resin Modified Glass Ionomer Cement (RM-GIC) and composite restorations (CR) made with a bonding agent containing functional agents.
(25,32) In experiments designed to evaluate the anticaries effect of low-fluoride toothpastes under different cariogenic conditions, it was demonstrated that, for caries-active children (33) or for those subject to a high cariogenic challenge
(biofilm accumulation and exposure to sugar 6-8 times/day), (28) low-fluoride toothpaste is significantly less effective than conventional fluoride toothpaste (1100 ppm F) in controlling caries progression.
Thus, a concentration of 1100 [micro]g F/g might not be high enough to reduce dentine demineralization if this dental tissue is exposed to a high cariogenic challenge
by biofilm accumulation and sugar exposure over time.