Influence of acidulated phosphate fluoride agent and effectiveness of subsequent polishing on composite material surfaces

This study examined the surface morphological changes of prosthodontic composite materials when exposed to an acidulated phosphate fluoride (APF) agent and the effectiveness of subsequent polishing on APF-treated material surfaces. Nine composite materials (Conquest Sculpture, Dentacolor Sirius, Diamond Crown, Estenia, Eye Sight, Gradia, New Meta Color Infis, Prywood Color and Vita Zeta) were assessed. After half the surface of each composite disk specimen was coated with a varnish, the entire surface was treated with an APF solution (Floden A). The varnish was removed and a surface analyzer helped to determine changes in the surface roughness value (Ra). A scanning electron microscope (SEM) was used to observe relief patterns for all specimens. The composite surfaces treated with the APF were then polished and examined using the SEM. Ra values for the Conquest Sculpture, Diamond Crown, Estenia, Gradia and Prywood Color materials (macro inorganic filler) showed a significant increase as a result of treatment with the APF solution, and the macro-inorganic fillers (Estenia, Prywood Color) demonstrated noticeable etched patterns. There were no significant statistical differences in Ra values between the treated and untreated halves for any of the microfilled materials. In addition, photographs of the microfilled materials indicated no changes in the surfaces and showed the effectiveness of polishing on the material surfaces. Microfilled material surfaces were not sensitive to the APF agent compared with macroinorganic filled material surfaces. For the latter, the effectiveness of surface polishing was demonstrated.