pH Evaluation over a Period of 6 months of Two-bottle Water-based Self-etching Primers: An In Vitro Study

Abstract

Aim and objective: The objective of this study was to monitor the pH stability over a period of 6 months of two-bottle self-etching (SE) primers. Materials and methods: Four commercially available two-bottle SE primer solutions, Adhese SE (Ivoclar Vivadent; Schaan, Liechtenstein), Clearfil SE (Kuraray; Tokyo, Japan), Contax Primer (DMG; Hamburg, Germany), and Enabond SE (Micerium; Avegno (Ge), Italy), containing water as the main solvent were selected. The pH values during a 6-month storage period at intermittent temperature were daily measured by means of a microprocessor-based pH/temperature meter and hence recorded, tabulated, and analyzed. Results: The mean values of overall pH measurements and standard deviation for Adhese SE, Clearfil SE, Contax Primer, and Enabond SE are, respectively, 1.70 (±0.01), 1.72 (±0.01), 1.20 (±0.01), 1.80 (±0.01). One-way ANOVA did not detect any significant change of the mean pH values of all measurements over time. Conclusion: The conventional 6-months storage did not affect the pH values of the water-containing primers of two-bottle SE adhesives. Clinical significance: This study provides evidence that conventional storage under adequate conditions did not affect the pH values of the water-containing primers of two-bottle SE adhesives with different monomer formulations. Clinicians may rely on the known pH value of the selected SE adhesive during shelf-life.