Comparative evaluation of marginal microleakage around fluoride containing, traditional, and non-gamma-2 amalgam restorations in vitro

Marginal micro leakage occurring around a fluoride-containing amalgam was evaluated and compared to that occurring around other types of amalgam. Three types of amalgam alloys were studied, a fluoride - containing amalgam [Flour Alloy], a traditional amalgam [Solila Alloy] and a non-gamma-2 amalgam [Luxalloy]. Micro leakage was evaluated in vitro using a standardized class V restorations and dye penetration. Micro leakage scores were recorded after two days, two, four, and six months of storage in phosphate buffered saline[PH=6].The results of this study indicated that the sealing properties of fluoride containing amalgam were superior to that of the non-gamma-2 amalgam. However, the addition of fluoride to the amalgam alooy did not improve its sealing ability compared to that of the traditional amalgam

use of a dentin adhesive instead of enamel bonding agent to reduce the etching time of enamel in primary teeth

Forty exfoliated primary incisors were divided into four groups. In two groups, enamel bonding agent was applied after etching the enamel for either 60 or 120 seconds. In the other two groups, universal bonding agent was applied after etching for either 60 or 30 seconds. The shear bond strength was evaluated in the four groups. The use of the universal bonding agent after etching the enamel for 60 seconds showed the highest shear resin bond strength. This bond strength did not differ significantly from that obtained with etching for 120 seconds followed by the application of enamel bond. Also, there was no significant difference between etching for 60 or 120 seconds before using the enamel bonding agent. It could be concluded that etching the enamel for 60 seconds is adequate for primary teeth. Etching time could be reduced to 30 seconds when a dentin adhesive designed to bond to the inorganic component of the tooth is used for resin bonding