Effect of Argon laser Activation on Some Properties of Different Composite Resins

Abstract

This study was conducted to investigate the effect of argon laser. activation on some properties of different shades of composite resins. Two types of composite resins were used; microfilled and hybrid: Three shades of each composite (light, universal and dark) were utilized.

A total of one thousand, six hundred and eighty specimens; 480 of each composite, were prepared in accordance with the ADA specification No. 27 for direct filling resins. One half of these specimens (420 specimens) was activated by argon laser and the other half was activated utilizing visible light. The three different shades of the argon laser activated composite specimens (microfilled and hybrid types) were tested immediately and following dry and wet storage. Testing of the composite •specimens was carried out following storage at three different post-: polymerization times: one day, one week and one month. Same storage conditions and testing periods were also followed with the three different shades of the visible light activated composite specimens (microfilled and hybrid types). Degree of conversion, hardness, tensile strength as well as dimensional change were determined for all composite specimens FTIR spectroscopy was utilized to determine the degree of conversion (DC) using the KBr pellet technique. Hardness was evaluated utilizing Vickers hardness tester. The diametral tensile strength testing was carried out on a Universal testingmachine. Finally, measurements of dimensional change were determined using an electronic caliper. From this study, the ,, following conclusions could be drawn: 1. The degree of conversion values ofthe argon laser activated hybrid composite were higher than those activated by visible light following one week storage.