Changes in surface roughness of primary dentin after conditioning treatments

Dentin roughness is one of the factor influencing dentin wettability and bond strength. Objectives: To evaluate the effect of different conditioning treatments of primary dentin for resin bonding on its surface roughness. Methods: Human primary dentin surfaces were obtained and treated with: 1) Polished (1/4 mm diamond paste), 2) After polishing, 35% phosphoric acid was applied for 7 s or 15 s and washed out with water for 30 s, 3) After polishing, Clearfil SE Bond (SEB) primer was applied for 10 s or 20 s and afterwards removed trough washing and ultrasonic agitation with different alcohol solutions, 4) After polishing, One Up Bond F (OUB) was applied for 10 s or 20 s and afterwards removed from the surface. Digital images (20 x 20 microns) from the surfaces were obtained by means an AFM microscope (Nanoscope IIIa- Digital Instruments). Roughness in the total area and intertubular roughness (Ra) were measured. Data were analyzed by One-way Anova and SNK multiple comparisons tests (p<0.05). Results: Mean roughness (Ra-microns) and standard deviations are presented in the table. Means with the same symbol are not different. Conclusions: All tested treatments increased primary dentin surface roughness. The highest increase in total roughness was obtained by phosphoric acid, meanwhile intertubular roughness attained similar roughness values when applying OUB or phosphoric acid. Acknowledgements: CICYT/FEDER MAT2004-06872-C03-02.