Introduction: Carbonic anhydrase 6 (CA6) is the only secreted member of the carbonic anhydrase enzyme family. This enzyme catalyzes the reversible hydration of carbon dioxide: CO2 + H2O ⇔ H+ + HCO3-. The dehydration reaction contributes to net acidification in several tissues and biological fluids. Salivary CA6 attaches to the enamel and predisposes to caries probably by acidifying the dental biofilm ...