[Surface analysis of 2 composite filling materials after various methods of finishing and sealing]

The surface quality of 2 composite filling materials (Adaptic with coarse hard quartz fillers and Cosmic with fine softer glass fillers) was evaluated using profilometry, scanning electron microscopy and light reflectometry after finishing with experimental diamond discs, 3M discs, corundum discs, polishing paste and also after sealing. Plaque formation on standardized surfaces of both composites was photographically recorded in 20 subjects. The sealed surfaces and the surfaces finished by the matrix alone were approximately 10 times less rough than after finishing procedures. Under in vivo conditions they reflected the most light, for both composites. The sealer failed to cover the whole composite surface. The unfinished and sealed surfaces lost their shine 3-7 days after placement in the mouth. Decrease in reflectance was independent of mechanical oral hygiene procedures. There were no significant differences in the roughness produced by the various discs on Adaptic surfaces. Diamond discs with particle size 1-3 micrometer resulted in least surface roughness and were the only instruments not destroying the filler particles of either composite. 3M discs and the rough corundum discs caused significantly more surface roughness of the Cosmic surface. Reflectometry showed that the finishing methods unfavourably affected composite surface smoothness. Among all finishing methods polishing paste produced the highest reflection value on the Cosmic surface. Adaptic surfaces were always associated with more plaque formation than Cosmic surface after all finishing methods.