Dear Editor:

Our paper Habiba et al. 2016 [1] made appropriate analyses. While the point raised by Mortazavi et al. [2] is good, we considered the idea that dental amalgam could be a confounding effect. A question on having dental amalgam was included in our questionnaire. However, none of the respondents had dental amalgam; thus, we made no mention of the influence of dental amalgam in our manuscript.