1. In the first phase, children are required to bring at the day care centres the tooth brush and the toothpaste used at home. There is no randomization, since the inclusion in either children's or regular toothpaste groups will be done based on each child's preference. The children are requested to tooth brush as the usual manner that the parent and the child do at home. Saliva expectorates are collected as the protocol described by Guha-Chowdhury et al. (1996). No instructions are provided in this phase or interventions by the researcher. Saliva expectorates are collected for further laboratory analysis. Toothpastes are collected for laboratory analysis.