A Study to Evaluate the Cariostatic Efficacy of Nano Silver Fluoride (NSF) vs. Silver Diamine Fluoride (SDF) in Children

Inclusion Criteria * Are between the ages of 6 to 10 years. * Are medically healthy. * Have a minimum of one permanent deciduous molar tooth and one permanent first molar with an occlusal and/or proximal carious lesion classified as ICDAS II (International Caries Detection and Assessment System) Stage 3-4 (moderate caries) or Stage 5-6 (advanced caries). * Must be able to understand and be willing to provide written child assent and parent/guardian consent for study participation. * Must be willing and able to attend all study visits. * Must be able to read and understand English and/or Spanish. * Must be willing to provide feedback about study outcomes in their child (patient-reported/parent-reported outcome measures). Exclusion Criteria * Have a known sensitivity/allergy to fluoride, silver or other heavy-metal ions. * Have a significant medical history, such as cardiac conditions that require antibiotic prophylaxis prior to dental treatment, or poorly controlled/uncontrolled diabetes. * Present with ulcerative gingivitis or aphthous stomatitis. * Have a history of full mouth gingivectomy. * Chronically take medications that reduce salivary flow, including stimulants for ADHD and antihistamines for seasonal allergies. * Have a history of systemic disease that reduces salivary flow, such as an autoimmune disease. * Deciduous molars are loose at the initial screening examination visit. * Deciduous molars or first permanent molars with occlusal and/or proximal caries have an existing restoration or recurrent caries at the site of potential study treatment. * Deciduous molars or first permanent molars have extensive occlusal and/or proximal caries with pulpal involvement and/or require surgical intervention for treatment.