Calcium and Microhardness Quantification in Healthy and Fluorotic Dentin Conditioned with a Self-Etching System: An In Vitro Study

<b>Background:</b> Dental fluorosis can affect the micromorphology of dentin, a fact that could present constraints relating to the structural, mechanical, and chemical stability of dentin when it is demineralized in operative maneuvers. <b>Introduction:</b> The aim of this article is to quantify the amount of calcium and the microhardness of both a healthy and a fluorotic dentin through conditioning with a two-step self-etching system (Optibond Versa, Kerr, CA, USA). <b>Methods:</b> Dentin samples were obtained from healthy molars diagnosed with mild, moderate, and severe fluorosis. The amount of calcium was quantified utilizing an atomic absorption spectrophotometer. The hardness was evaluated using a Vickers durometer. Two dentin samples from each study group were examined using scanning electron microscopy (SEM). <b>Results:</b> A one-way analysis of variance (ANOVA) and Tukey-Kramer test were applied as post hoc tests for determining the differences in calcium values between the study groups and to show the difference in the hardnesses evaluated. The Student's t-test was applied to related samples. The level of significance was set at <i>p</i> < 0.05. Statistically significant results were obtained for the amount of calcium and microhardness of the healthy dentin group. The SEM images demonstrated irregular etching patterns in the fluorotic dentin, indicating potential bonding challenges. <b>Conclusion:</b> In conclusion, there is a lower amount of calcium and a significant reduction in microhardness in healthy dentin when applying the self-etching system compared to fluorotic dentin. Fluorotic dentin is more resistant to demineralization, which may influence adhesive bonding strategies. Clinicians should consider adjusting conditioning protocols for optimal adhesion in fluorotic teeth.