The Effect of Filler Loading and Packing Technique on Physical Properties and Nanoleakage of Different Composite Formulations

Abstract

This study was performed to evaluate the effect of different filler loading and different packing techniques on some physical properties of resin composite materials as well as their effect on the occurrence of nanoleakage in extracted human teeth immediately, after six months and after 12 months of water storage. To evaluate water sorption and solubility, 10 specimens were made from each resin composite material; Filtek Z350XT and GrandioSO, packed either horizontally, obliquely or vertically and stored for either one week, six months or 12 months. In addition, another 10 specimens were made from Xtra Fil by bulk packing as a control group. In the first stage, specimens were desiccated and weighed till a constant dry mass was recorded. In the second stage, specimens were stored in water for the prespecified storage time in an incubator. Then saturated mass was recorded. At the third stage, specimens were desiccated and weighed till a final constant dry mass was reached and recorded. The three recorded mass values as well as the measured height and diameter values of each specimen were used to calculate water sorption and solubility values using Oysaed and Ruyter formula.