Effect of glycerin on the surface hardness of composites after curing
نویسندگان
چکیده
Growing patient demands for esthetics and concerns about environmental contamination by amalgam have led to a large increase in restorations using dental composites. Polymerization of dental composites occurs through a chain reaction that is induced by free radicals. If composite is exposed to air during this process, oxygen in the air decreases the excitability of the photo initiator and stabilizes the free radicals, causing polymerization interference or delay. As a result, oxygen inhibition layer (OIL) is formed on the surfaces of cured composites. Depending on the type of composite used, the thickness of the OIL is between 10 and 200 μm. The OIL adversely affects the prognosis of composite Effect of glycerin on the surface hardness of composites after curing
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