IRCT20171020036896N4 IRCT 2018-03-09 Kerman University of Medical Sciences The antibacterial effectiveness of thymes and chamomile extract and chlorhexidine and on the salivary Streptococcus mutans ندارد Comparison of the antibacterial effectiveness of thymes and chamomile extract and chlorhexidine on the salivary Streptococcus mutans of preschool childrens with early childhood caries by the quantitative Real Time PCR 2017-12-22 anticipated 90 Complete https://irct.ir/trial/27451 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Health service research, Randomization description: Simple randomization or unrestricted method will be used and randomization unit is Individual .we will use from Roll of a die from the methods of simple randomization because there are 3 groups in this study that actually the tool of randomization is dice. So the numbers 1 and 2 are for the first group (chlorhexidine) 3 and 4 for the second group ( thymes) and 5 and 6 for the third (chamomile). The next step Allocation concealment will be done, In such a way that the allocated group is not known before the assignment of the individual. To achieve this goal, a non-transparent, sealed, random sequence envelope is used . In this way, the statistical specialist will provide 90 envelopes and each of the randomly generated links will be recorded on a card and the cards are arranged in the envelopes . In order to maintain a random sequence, the numbering of envelopes on the outer surface is done in the same order. Finally, the envelops are enclosed and placed in the box, respectively. At the time of the implementation of the study, according to the order of entry of eligible participants, one of the envelopes is opened respectively and will determine the group assigned to that participant. In this study, the assistant of Pediatric Dentistry examines the participants in terms of inclusion and exclusion criteria. Randomization methods are done by an statistical specialist and performance of the study is done by a trained dental student, Blinding description: Because all the materials are in the same consistency gel, in a uniform shape and color, considering the informed consent, participants are unaware of material that what materials is used for. Outcome evaluator, who performs PCR, is also unaware of the groups. 3 Streptococcus mutans. Intervention 1: Intervention group1: thyme extract 5% , 30 minutes and 1 week after first salivary sampling from 4 to 6 year old children, 1 cc gel measured with a syringe and with a cotton swab is applied to all teeth of the child. Intervention 2: Intervention group2: Chamomile extract 5% , 30 minutes and 1 week after first salivary sampling from 4 to 6 year old children, 1 cc gel measured with a syringe and with a cotton swab is applied to all teeth of the child. Intervention 3: Control group1: cholorhexidine 0.02 % , 30 minutes and 1 week after first salivary sampling from 4 to 6 year old children, 1 cc gel measured with a syringe and with a cotton swab is applied to all teeth of the child. No - There is not a plan to make this available Justification or reason for not sharing IPD is Because the study data do not have any other scientific application.