Evaluating the Effect of Sumac Extract on Dentine Micro-Hardness during pH Cycling

Statement of the Problem:

 Although sumac extract (SE) is reported as a collagen cross linker, the available data regarding its effect on the dentine micro-hardness is quite sparse.

Therefore, the aim of this study includes evaluating the effect of different concentrations of SE on dentine micro-hardness comparing to grape seed extract (GSE).

In this experimental study, the GSE was purchased from available market and convert to 5% solution. Meanwhile the 5, 10, and 20% of SE solutions were prepared experimentally. The base line micro-hardness of 60 samples (30 premolars divided to buccal and lingual segments) was recorded triplicate for each specimen and they were randomly divided into 5 groups (four abovementioned experimental solutions and de-ionized water as negative control). For 35 consecutive days, each sample was twice pH cycled and treated by solutions. Ultimately, the final micro-hardness was recorded triplicate again for each sample and the numerical data was compared with each other using one-way ANOVA and Tukey HSD Post Hoc tests (α=0.05).     

The mean±SD values of micro-hardness for the groups was recorded as 54.45± 13.4, 65.65±18.5, 39.57±2.26, 41.13±1.66 and 43.79±4.96 at base line and 10.4±0.99, 11.85± 0.75, 10.16±1.84, 8.48±1.16 and 6.31±1.01 at final stage for control, GSE 5%, SE 5%, SE 10% and SE 20% respectively. There was no significant difference among the micro-hardness of the groups before treatment (p= 0.369). However, after experimental treatment, there was significant difference between the groups (p= 0.024) while in pairwise comparison just two groups (GSE 5% and SE 20%) had significant difference with each other (p= 0.017).

The efficacy of SE was reversely related to its concentration. Moreover, neither GSE nor SE had significant effect on dentine micro-hardness after 35 day pH cycling.