Inclusion Criteria  Male and/or female subjects 16 years and above Minimum of 20 natural uncrowned teeth (excluding third molars) must be present Caries active subjects will have at least 3 active caries lesions (ICDAS score 1 - 3). Caries free control subjects will either have ICDAS score 0 or ICDAS score of 1 - 3 where the lesion is inactive. Available throughout entire study Willing to use only assigned products for oral hygiene throughout the duration of the study Must give written informed consent Must be in good general health  Exclusion Criteria  Unwilling or unable to sign an Informed Consent Form Advanced periodontal disease Medical condition which requires premedication prior to dental visits/procedures Diseases of the soft or hard oral tissues Orthodontic appliances that interfere with clinical assessments Impaired salivary function Current use of drugs that can affect salivary flow Use antibiotics 3 months prior to or during this study Use of any arginine containing oral care products such as Colgate Sensitive Pro-Relief and Colgate Maximum Cavity Protection plus Sugar Acid Neutralizer dentifrices 3 months prior to or during this study Pregnant or breastfeeding Participate in another clinical study 1 week prior to the start of the washout period or during the study period Use of tobacco products Allergic to common dentifrice ingredients Allergic to amino acids Immune compromised individuals (HIV, AIDS, immuno-suppressive drug therapy)