The effects of lesion baseline characteristics and different Sr:Ca ratios in plaque fluid-like solutions on caries lesion de- and remineralization

Arch Oral Biol. 2012 Oct;57(10):1299-306. doi: 10.1016/j.archoralbio.2012.08.012. Epub 2012 Sep 7.

Abstract

This study investigated the effects of lesion baseline characteristics and different strontium (Sr) to calcium (Ca) ratios in plaque fluid-like solutions (PF) on lesion de- and remineralization. Caries lesions were formed in enamel using three protocols: methylcellulose acid gel (MeC) and partially saturated lactic acid solutions containing carboxymethylcellulose (CMC) or not (SOLN). Lesions were exposed to PF with four distinct Sr:Ca molar ratios (0:1/3:1:3), but otherwise identical composition and total Sr+Ca molarity, for seven days. Lesions were characterized using transverse microradiography (TMR) at baseline and post-treatment. At baseline, MeC and CMC had similar integrated mineral loss values, whereas SOLN lesions were more demineralized. All lesions showed significant differences in their mineral distributions, with CMC and SOLN having lower R values (integrated mineral loss to lesion depth ratio) than MeC. Post-PF exposure, no interaction was found between lesion type and Sr:Ca ratio. Within lesion type, MeC demineralized, whereas CMC and SOLN exhibited some remineralization, with the differences between MeC and the other lesion types being of statistical significance. Within Sr:Ca ratio, the 1:3 ratio exhibited some remineralization whereas other groups tended to demineralize. Only the difference between groups SrCa1/3 and SrCa0 was of statistical significance. In summary, both lesion baseline characteristics and Sr:Ca ratio were shown to effect lesion de- and remineralization. Under the conditions of the study, high-R lesions are more prone to demineralize under PF-like conditions than low-R lesions. In addition, partial Sr substitution for Ca in PF was shown to enhance lesion remineralization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Calcium Chloride / chemistry
  • Calcium Chloride / pharmacology*
  • Cattle
  • Dental Caries / chemically induced
  • Dental Caries / drug therapy*
  • Dental Plaque / chemistry*
  • In Vitro Techniques
  • Lactic Acid
  • Methylcellulose
  • Microradiography
  • Solutions / chemistry
  • Strontium / chemistry
  • Strontium / pharmacology*
  • Tooth Demineralization / chemically induced
  • Tooth Demineralization / drug therapy*
  • Tooth Remineralization / methods*

Substances

  • Solutions
  • Lactic Acid
  • Methylcellulose
  • Calcium Chloride
  • Strontium