Surface characterization of modern resin composites: a multitechnique approach.
OBJECTIVE
To characterize the surface properties of some modern resin composites employing a series of physicochemical methods.


METHODS
Specimens from three microhybrid (Palfique Estellite-PE, Z250 Filtek-ZF, Tetric Ceram-TC) and one nanofilled (Supreme Filtek-SF) conventionally photo-cured resin composites polished with Soflex disks were studied for the following properties: Surface chemical composition and degree of C=C conversion (FTIR), surface energetics (contact angles), surface texture (AFM), surface roughness (AFM, stylus profilometry) and gloss (60 degrees-, 20 degrees-angle specular gloss).


RESULTS
Polar and non polar molecular groups were identified in all products including NH and CONH (SF, ZF, TC). SF and ZF demonstrated higher conversion than PE and TC (P< 0.05). No significant differences (P> 0.05) were found in critical surface tension, total work of adhesion and its polar and dispersion components, the latter being the highest in all products. AFM showed the smoothest surface texture in PE. The ranking of Sa, Sq, Ra and Rz roughness parameters was PE<SF<ZF, TC (P< 0.05). 20 degree-angle gloss measurements (PE, SF>ZF>TC, P< 0.05) were more sensitive than 60 degree-angle measurements (PE, SF>TC, P< 0.05) in revealing gloss differences. A positive correlation was found between Sa and Ra and a negative one between Sa and 20 degree-angle gloss.
Biomaterials Science Research Group, School of Dentistry, The University of Manchester, UK.
Nick
N
Silikas
Katerina
K
Kavvadia
George
G
Eliades
David
D
Watts
D000268:Adhesiveness; D002244:Carbon / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003188:Composite Resins / Q000737:chemistry*; D003775:Dental Polishing / Q000295:instrumentation; D006801:Humans; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013500:Surface Tension; D013674:Technology, Dental; D017155:Wettability
D003188:Composite Resins; C474035:Filtek Supreme; C444701:Filtek Z250; C121818:Tetric ceram; C086113:palfique estelite; D002244:Carbon