Comparative evaluation of compressive strength and fracture resistance of posterior restorative materials alkasite and newer glass ionomers with amalgam: An in vitro study

Aim: The conventional restorative materials amalgam and glass ionomer have multifarious drawbacks leading to introduction of newer materials with superior biomechanical attributes. The present study aimed to assess and compare the compressive strength of ceramic-reinforced glass ionomer cement, zirconia-reinforced glass ionomer cement, high strength glass ionomer posterior restorative material, alkasite restorative material, and amalgam when used as posterior restorative materials. Materials and Methods: Five restorative materials were evaluated: modified glass ionomer cements including ceramic-reinforced, zirconia-reinforced, and high strength glass ionomer; alkasite restorative material; and dental amalgam. Fifty cylindrical specimens were fabricated using test materials (n = 10 for each group). Class II cavities prepared on 50 intact permanent molars were restored with test materials. After thermocycling and 24 h of storing, the specimens in artificial saliva, compressive strength, and fracture resistance were tested. Data were analyzed statistically. One-way analysis of variance and post hoc Tukey test were used for intergroup comparison. Pearson's correlation was used for correlating the maximum load by cylindrical and tooth specimens. Results: A significantly high compressive strength was displayed by specimens of group 4, followed by group 5, group 3, group 1, and least by group 2. The highest fracture resistance was displayed by teeth restored with the test materials in group 4, group 1, group 5, group 2, and least by group 3. Conclusion: Within the limitations of the present study, alkasite restorative material (Cention N) showed the highest compressive strength in cylindrical and highest fracture resistance in tooth specimens.