Influence of different shades and LED irradiance on the degree of conversion of composite resins

Author(s)

Gaglianone, Livia Aguilera ^[1] ; Lima, Adriano Fonseca ^[1] ; Napoleao de Araujo, Larissa Sgarbosa ^[1] ; Cavalcanti, Andrea Nobrega ^[2] ; Marchi, Giselle Maria ^[1]

Affiliation

^[1] State Univ Campinos, Dept Restorat Dent, Operat Dent Area, Piracicaba Dent Sch, Piracicaba, SP - Brazil

^[2] Sch Med & Publ Hlth Bahia, Dept Oral Rehabil, Sch Dent, Salvador, BA - Brazil

• Document type: Journal article
• Source: Brazilian Oral Research; v. 26, n. 2, p. 165-169, MAR-APR 2012.
• Web of Science Citations: 8

Abstract

The aim of this study was to evaluate the degree of conversion (DC) of two composite resins with different shades that were light cured by light-emitting diodes (LEDs) of different irradiances. Specimens (5 mm x 2 mm) were prepared with a nanofilled (Filtek Supreme A2E, A2D, and WE) or microhybrid resin (Opallis A2E, A2D, and EBleach Low) and were randomly divided into 12 groups (n = 5 each) according to the composite resin and light-curing unit (Elipar Free Light 2, 1250 mW/cm(2); Ultralume 5, 850 mW/cm(2)). After 24 h, the DC was measured on two surfaces (top and bottom) with Fourier Transform infrared spectroscopy (FTIR). Data were statistically analyzed with two-way ANOVA and Tukey test (alpha = 0.05). Statistical differences among the surfaces were observed in all experimental conditions, with higher values on the top surface. The microhybrid resin presented the highest DCs for shades A2E and A2D on the top surface. The LED with higher irradiance promoted better DCs. Taken together, the data indicate that the shade of a composite resin and the irradiance of the light source affect the monomeric conversion of the restorative material. (AU)

• FAPESP's process: 07/02800-3 - Effect of light curing modes and light curing time on degree of conversion and leachability of uncured substances of bonding systems and composite resins
• Grantee: Flávio Henrique Baggio Aguiar
• Support Opportunities: Regular Research Grants
• FAPESP's process: 09/08992-7 - Effect of direct and trans-dentinal application of low level laser on odontoblast cells exposed to bleaching agents
• Grantee: Adriano Fonseca de Lima
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 09/03661-2 - Effect of different volatilization times and temperatures of solvents on degree of conversion and mechanical properties of dentin bonding systems
• Grantee: Larissa Sgarbosa de Araújo Matuda
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 09/03763-0 - Influence of different curing light sources, depth of cure and storage in mechanical properties of different adhesive systems.
• Grantee: Lívia Aguilera Gaglianone
• Support Opportunities: Scholarships in Brazil - Master