Water sorption of CH3- and CF3-Bis-GMA based resins with additives.

Autor:	Prakki A; Department of Clinical Sciences, Restorative Dentistry, Faculty of Dentistry, University of Toronto, Toronto, Canada. anuradha.prakki@dentistry.utoronto.ca, Cilli R, Vieira IM, Dudumas K, Pereira JC
Jazyk:	angličtina
Zdroj:	Journal of applied oral science : revista FOB [J Appl Oral Sci] 2012 Jul-Aug; Vol. 20 (4), pp. 472-7.
DOI:	10.1590/s1678-77572012000400014
Abstrakt:	Objectives: To evaluate the effect of additives on the water sorption characteristics of Bis-GMA based copolymers and composites containing TEGDMA, CH3Bis-GMA or CF3Bis-GMA. Material and Methods: Fifteen experimental copolymers and corresponding composites were prepared combining Bis-GMA and TEGDMA, CH3Bis-GMA or CF3Bis-GMA, with aldehyde or diketone (24 and 32 mol%) totaling 30 groups. For composites, barium aluminosilicate glass and pyrogenic silica was added to comonomer mixtures. Photopolymerization was effected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Specimen densities in dry and water saturated conditions were obtained by Archimedes' method. Water sorption and desorption were evaluated in a desorption-sorption-desorption cycle. Water uptake (%WU), water desorption (%WD), equilibrium solubility (ES; µg/mm³), swelling (f) and volume increase (%V) were calculated using appropriate equations. Results: All resins with additives had increased %WU and ES. TEGDMA-containing systems presented higher %WU, %WD, ES, f and %V values, followed by resins based on CH3Bis-GMA and CF3Bis-GMA. Conclusions: Aldehyde and diketone led to increases in the water sorption characteristics of experimental resins.
Databáze:	MEDLINE
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