Linseed based saliva substitutes and their effect on mineral dissolution of predemineralized bovine dentin in vitro

Abstract 

Objectives

Polymers used in saliva substitutes might inhibit remineralization. The present study evaluated the effects of various calcium, phosphate, and fluoride concentrations of linseed based solutions on the mineral loss of predemineralized bovine dentin in vitro.

Methods

Dentin specimens were prepared, embedded and polished. The specimens were demineralized (pH 5.6; 6 d; 37°C) and half of each sample was covered with nail varnish. Subsequently, the specimens (n=10) were exposed to 14 linseed based solutions (calcium 0–1.1mM; phosphate 0–7.7mM, fluoride 0–0.03mM) at pH 5.5 and 6.5 as well as to Salinum^® for 14 days (37°C). The differences in mineral loss (ΔΔZ) between the values prior to and after storage in the solutions were evaluated from microradiographs of thin sections.

Results

After the exposure to the various solutions decreased mineral contents compared to those after demineralization could be observed (p<0.05; paired t-test) whereas for the specimens stored in solution with the highest calcium and phosphate concentration no significant change in mineral loss could be evaluated (p>0.05). Salinum^® induced a significantly greater mineral loss compared to the equivalent saturated solution (p<0.05; ANOVA, Bonferroni). The general linear model revealed a significant dependency for ΔΔZ on ‘phosphate’ (p=0.000) and ‘fluoride’ (p=0.001), but not on ‘calcium’ (p=0.397) and ‘pH’ (p=0.368).

Conclusions

The addition of calcium, phosphates, and fluorides seems to have a positive effect on the remineralizing qualities of linseed based saliva substitutes.

Keywords: Bovine dentin, Linseed, Microradiography, Remineralization, Demineralization, Saturation of apatites, Octacalciumphosphate, Saliva substitute