IRCT20171020036896N3 IRCT 2018-03-04 Kerman University of Medical Sciences The effect of Green tea, Chlorhexidine and green coffee extract on salivary Streptococcus mutans ندارد Comparison of the effect of metanolic green tea، green coffee extract and chlorhexidine and on the salivary Streptococcus mutans ُin preschool children with early childhood caries by the PCR 2017-12-22 anticipated 90 Complete https://irct.ir/trial/27450 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Prevention, 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 (green coffee) and 5 and 6 for the third (green tea). 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. Outcome evaluator, who performs PCR, is also unaware of the groups. 3 Streptococcus mutans. Intervention 1: Intervention group:Green tea methanolic extract 20%, for 30 minutes and 1 week after saliva taking from 4 to 6 year old children, 1 cc gel with a syringe and a cotton swab is applied to all teeth of the child. Intervention 2: Intervention group: Green coffee 10% , for 30 minutes and 1 week after saliva taking from 4 to 6 year old children, 1 cc gel with a syringe and a cotton swab is applied to all teeth of the child. Intervention 3: Control group: Chlorhexidine 0.2% , 30 minutes and 1 week after saliva taking from 4 to 6 year old children, 1 cc gel with a syringe and a cotton swab is applied to all teeth of the child. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is Because the study data do not have any other scientific application.