Abstract
The aim was to investigate the surface roughness of de-bonded ceramic surfaces with residual resin when treated with different resin removal treatment protocols. Sixty disc specimens of 5mm diameter and 3mm height of Lithium disilicate ceramic (IPS Emax Press) were fabricated. All specimens were treated with Hydrofluoric (HF) acid (9.5%) for 30 secs. Except 10 specimens as controls, all received silane treatment and a resin cement build-up (3mm x 2mm). All build-ups were sheared with universal testing machine and residual resin was removed using 5 protocols. Group 1: No treatment; Group 2: Bur treatment; Group 3: Heat treatment at 650 degrees C (1min); Group 4: Heat treatment at 750 degrees C (7 min); Group 5: Sandblasting (Al2O3) (2 min). The surface roughness (Ra) of all specimens was assessed using a non-contact laser surface profilometer. Data was assessed using ANOVA and multiple comparisons test. The highest roughness value was observed in the ceramic specimens exposed to sandblasting (Gp 5), which was 9.027 (1.362) mu m. However the lowest Ra was observed for Gp 1 specimens [5.092 (0847) mu m]. Overall, the difference among the study groups for surface roughness values was statistically significant (p<0.05). Presence of residual resin on de-bonded ceramic surfaces, compromises the surface roughness. Removal of residual resin with heat treatment at 650 degrees C (1min) and sandblasting significantly improved and restored the surface roughness of de-bonded ceramics in comparison to Hydrofluoric acid etched ceramic surface.