IRCT20140601017935N8 IRCT 2019-12-14 Yazd University of Medical Sciences Comparative evaluation of the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and Xylitol-containing chewing gum on salivary Comparative evaluation of the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and Xylitol-containing chewing gum on salivary flow rate, pH and concentration of calcium and phosphate 2019-12-21 anticipated 60 Complete https://irct.ir/trial/43029 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Randomization description: Simple randomization personal, using the random number table, Blinding description: The researcher does not know in which group each person belongs, and the outcome assessor is unaware of which group the samples were in. N/A Condition 1: chewing gum. Condition 2: chewing gum. Intervention 1: Intervention group:First Intervention group : First,They will brush twice daily for 3 weeks with a toothbrush(Medical) and toothpaste(Nasim). On the sampling day they will not eat anything for 2 hours and then give them a chewing gum CCP-ACP (Trident Recaldent with The peppermint flavor) is given and after 5 minutes of chewing, the saliva is collected. Intervention 2: Intervention group: : second Intervention group : First,They will brush twice daily for 3 weeks with a toothbrush(Medical) and toothpaste(Nasim). On the sampling day they will not eat anything for 2 hours and then give them a chewing gum Xylitol (Trident) with The peppermint flavor is given and after 5 minutes of chewing, the saliva is collected. Intervention 3: Control group: First,They will brush twice daily for 3 weeks with a toothbrush(Medical) and toothpaste(Nasim). On the sampling day they will not eat anything for 2 hours and then give them a piece of paraffin is given and after 5 minutes of chewing, the saliva is collected. 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 this project is a thesis. Further study of the study protocol will be published