H Baharav1, T Brosh, R Pilo, H Cardash. 1. Section of Oral Rehabilitation, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel.
Abstract
PURPOSE: We compared the effect of irradiation time on the diametral tensile strength and stiffness of three visible light-cured composites. The sensitivity of the two mechanical properties to differentiate between the materials was also investigated. MATERIAL AND METHODS: Cylindrical specimens of three composites were cured for 20, 40, 80, and 120 seconds (n = 10) and loaded up to failure in a diametral tensile strength test. Stiffness and diametral tensile strength values were recorded. RESULTS: Irradiation time significantly influenced diametral tensile strength (p = 0.0017) and stiffness (p = 0.0002). With the same irradiation times the three tested materials demonstrated no significant difference when diametral tensile strength was studied (p = 0.31). However, stiffness values did show a significant difference (p = 0.0002). CONCLUSIONS: This study found that stiffness is more sensitive in disclosing differences in tensile properties between the materials than diametral tensile strength.
PURPOSE: We compared the effect of irradiation time on the diametral tensile strength and stiffness of three visible light-cured composites. The sensitivity of the two mechanical properties to differentiate between the materials was also investigated. MATERIAL AND METHODS: Cylindrical specimens of three composites were cured for 20, 40, 80, and 120 seconds (n = 10) and loaded up to failure in a diametral tensile strength test. Stiffness and diametral tensile strength values were recorded. RESULTS: Irradiation time significantly influenced diametral tensile strength (p = 0.0017) and stiffness (p = 0.0002). With the same irradiation times the three tested materials demonstrated no significant difference when diametral tensile strength was studied (p = 0.31). However, stiffness values did show a significant difference (p = 0.0002). CONCLUSIONS: This study found that stiffness is more sensitive in disclosing differences in tensile properties between the materials than diametral tensile strength.