Effect of carbamide peroxide bleaching gel on composite resin flexural strength and microhardness

This study investigated the effect of 16% carbamide peroxide (Whiteness Perfect/FGM) on the Vickers microhardness and flexural strength of the restorative composites Filtek Z100 (hybrid), Filtek Z350 (nanofill), Brilliant (micro-hybrid) and Opallis (micro-hybrid). Discshaped (4×2 mm; n=5) and bar-shaped (12×2×1 mm; n=10) specimens of each restorative material were randomly divided into 2 groups: (G1) 16 weeks stored in distilled water; (G2) 16 weeks stored in distilled water, with 16% carbamide peroxide application during 6 h per day for the last 4 weeks. The mechanical properties were evaluated using a Vickers microhardness tester and a mechanical testing machine. Data were analyzed by twoway ANOVA and Tukey's (HSD) post-hoc test (α=0.05). Filtek Z100 presented the highest microhardness value, followed by Filtek Z350 and finally by Brilliant and Opallis (p=0.00). Filtek Z100 and Brilliant exhibited the highest flexural strength value, followed by Filtek Z350 and Opallis (p=0.00). Bleaching treatment decreased significantly microhardness of Brilliant and Opallis (p=0.00). The flexural strength of all studied materials was not affected by the home bleaching (p=0.28).

Draft resolutions adopted by the Economic Commission for Latin America at its Twentieth Session, Lima, Peru, 28 March-6 April 1984

Includes bibliography

Report of the Workshop to Develop a Plan of Action for the Small Island States of the Caribbean, Castries, Saint Lucia, 24-28 August 1987

Informe de la reunion en que se reviso el desarrollo cooperativo, la agricultura, la ciencia y tecnologia y el comercio y la industria de las islas pequenas del Caribe.

Informe de la Reunión Interinstitucional para Coordinar la Ejecución del Programa de Trabajo del CDCC, Nueva York, 28-30 junio 1976 = UN Inter-Agency Meeting on Co-ordination for Implementation of the Work Programme of the CDCC, New York, 28-30 June 1976

El símbolo ECLA/POS/76/10 corresponde al documento en inglés solamente