This study will require a total of 6 study visits over a 2 to 3 year period. The first study visit will last about one hour. At this study visit, parent-administered questionnaires will be used to collect information on the following: (a) the participant's demographic background (age, gender, and race), (b) socio-economic status (parents' income and housing condition), (c) participant's oral health practice (feeding histories, diet habits, oral hygiene measures, and dental attendance), and (d) systemic diseases. During the study visit, the participant's complete medical and dental history will be obtained and reviewed, and a dental exam will be performed in order to determine participants' caries status, and intraoral pictures may be taken of participants' teeth. At this visit and remaining visits participants will not be allowed to brush or clean teeth using any type of oral hygiene procedures for 8 hours prior to the visit. Saliva and plaque (the solf white-yellowish material on the tooth surface) will be collected at each visit. The Investigator will use a small probe to measure the pH of the dental plaque that builds up on the teeth. The participant will be asked to dip one finger into a glass containing a buffer solution and the probe will be placed on the teeth from which plaque will be taken. Plaque samples will be collected by gently scrapping the tooth using a sterile instrument. If the participant does not have enough plaque samples, they will be asked to return on the following day.
