SURFACE TOPOGRAPHY AND ENERGY DISPERSIVE X-RAY OF RESIN MATRIX CERAMICS CONDITIONED WITH AN ULTRASHORT PULSE LASER, TRI-BIOCHEMICAL SILICA, AND HYDROXYAPATITE - AN IN-VITRO STUDY

The effect of different surface modifiers, i.e., a tri-biochemical silica coating (TBC), an ultrashort pulsed laser (UPL), nano-hydroxyapatite (HA) on the surface roughness (Ra), and shear bond strength (SBS) of hybrid ceramics (HBCs) bonded to the resin luting cement was elucidated upon. Eighty-four squared HBC discs were prepared and randomly allocated into four groups based on the different surface pre-treatment: Group 1 (SB), Group 2 (TBC), Group 3 (UPL) and Group 4 (Nano-HA). A surface topography analysis was performed on one pair of samples from each group using scanning electron microscopy (SEM) followed by an EDX analysis. Forty discs underwent an Ra analysis using a profilometer. Luting cement was bonded to the HBC discs followed by artificial ageing on ten samples from each group. The SBS was measured using a universal testing machine and the failure was examined under a stereomicroscope. Data normality was assessed using the Kolmogorov-Smirnov test, and the Ra and SBS data were analysed using a one-way analysis of variance and Tukey's post-hoc test. (p ≤0.05). The maximum Ra (1075.21 ± 0.5 μm) and SBS (9.6 ± 0.1 MPa) scores were obtained in the Group 4 (HAp coating) specimens. Nevertheless, the Group 3 (UPL) treated discs demonstrated the lowest outcomes of the Ra (999.42 ± 1.1 μm) and bond strength scores (8.9 ± 0.2 MPa). The nano-hydroxyapatite and tri-biochemical silica coating can be used as an alternative to sandblasting to condition hybrid ceramics.