Resin-Based Cement Applied to Enamel and Dentin Pre-Treated with Phytic Acid: An In Vitro Study

Phytic acid (IP6) has the ability to etch tooth structure due to its acidity and chelating properties. This study aimed to evaluate the micro-tensile bond strength (μTBS) of resin-based cement to enamel and dentin using manufacturer-provided etchants, phosphoric acid (PA) for enamel and a mixture of 10% citric acid and 3% ferric chloride (CAF) for dentin and compare them to IP6. Enamel surfaces were etched for 30 s with either PA or IP6 (1%, 5% or 10%). Dentin surfaces were etched for 15 s with either CAF or 1% IP6. Pre-polymerized composite blocks were bonded to enamel and dentin surfaces. After 24 h, the specimens were sectioned into beams and subjected to μTBS testing. De-bonded specimens and smear layer removal were analyzed with a scanning electron microscope. Etching enamel with 1% and 5% IP6 resulted in μTBS values that are comparable to the control (PA) (p > 0.05), while 10% IP6 negatively affected the μTBS (p < 0.05). The μTBS to dentin etched with 1% IP6 was higher compared to the control (CAF) (p = 0.001). IP6 effectively removed enamel and dentin smear layer, and at specific concentrations, it may be a suitable alternative conditioner agent for bonding resin-based cement to enamel and dentin.