Abstract
Objective: The aim was to evaluate the volumetric dimensional changes of calcium aluminate glass-ionomer luting agent to resin modified-Glass ionomer cement (RM-GIC), self-etch and conventional resin based cement (RBC) among different storage conditions. Methods: Twenty
cylindrical specimens (7 mm × 2 mm) for four cements [Calcium aluminate (Ceramir-CM), RM-GIC (Fuji Plus-FP), RBC (Rely X Ultimate-RA) and RBC-self-etch (Rely X Unicem-RU)] were fabricated and polished. Five specimens from each material were randomly assigned to the four test conditions.
These conditions were silicone oil at 22 °C and 37 °C and distilled water at 22 °C and 37 °C respectively. A resolution balance was used to measure the weight of each specimen at 1, 2, 3 and 4 weeks. Archimedes' principle equations were used to measure volumetric dimensional
changes. Ion release analysis for Ca+ and OH- of the storage medium solution of calcium aluminate cement was performed using atomic absorption spectroscopy and pH measurement respectively at 1, 2, 3 and 7 weeks. Data was analyzed using ANOVA and Tukey post hoc test. Results:
A significant difference in volumetric changes (ρ < 0.05) was observed for different cements. Calcium aluminate (CM) showed maximum volumetric changes followed by FP. However, resin cements (RA and RU) showed significantly lower volumetric changes. Oil immersion exhibited shrinkage
and water immersion showed volumetric expansion in all materials. Increase in duration of immersion, increased the dimensional changes (shrinkage or expansion) among all cement groups (ρ < 0.05). Both temperature and duration showed significant influence on Ca+ ion
release. Conclusions: Calcium aluminate cement had the highest level of dimensional changes (17.28% and 20.52%) while both resin luting agents show least expansion without a significant difference between them. Ceramir luting agent expands significantly in water and continues to release
Ca2+ ions with time and higher temperature. The clinical use of calcium aluminate cements based on the high dimensional changes observed in the study is debatable.