Dimensional Changes in Dental Materials Stored in Phosphate Buffered Saline

Objectives: Dimensional stability is a critical feature of dental materials. This study measured and compared the length and weight of five dental materials stored in phosphate buffered saline.
Methods: Cylinders of 5 dental materials were made following the manufacturers directions. A 2.5 mm diameter tube was filled with one of the 5 materials and allowed to chemically polymerize (Biodentine) or was light cured (Calibra Universal, Calibra Bio, RelyX Ultimate, Panavia SA Universal) with a LED curing light/Deep Cure, irradiance >1000mW/cm2. The specimens were separated from the tubes, examined for defects and porous species discarded. The length of each specimen was measured using an electronic gauge 3 times and the average used as the baseline. The weight of each specimen was measured using a Mettler Balance and recorded. After measurements, the specimens were stored in sealed glass test tubes filled with phosphate buffered saline/98⁰F in an incubator. For subsequent measurements the specimens were removed from the test tubes, carefully dried using a laboratory tissue, and re-measured after 8 weeks, 9 weeks, and 10 weeks. The difference in length and weight from baseline to 10 weeks were analyzed by 1-way ANOVA and Tukey post-hoc analysis (alpha=.05).
Results: 1-way ANOVAs determined that there were significant differences between materials for length (p=.01) and weight (p<.01).
Materials with different superscripts in each row are significantly different.
Conclusions: Within the limitations of this study it can be concluded that Biodentine weight decreased more than other materials.