What concentration of phosphoric acid is used in acid etch?

In dental procedures, phosphoric acid is primarily used for acid etching, particularly when preparing enamel and dentin for adhesive bonding. The most common concentration utilized for this purpose is 37%. This concentration effectively removes the smear layer and enhances the surface roughness of the tooth structure, allowing for better mechanical interlocking with bonding agents used in restorative dentistry.

Using a concentration that is too low may not adequately prepare the surface, while a higher concentration could potentially damage the tooth structure or dentin, complicating the bonding process. Thus, the choice of 37% phosphoric acid reflects a balance that allows for effective etching while minimizing potential harm to the tooth. This makes it the standard choice in dental practices worldwide.