Cusp Deformation of Artificial Cavities by Silorane and Methacrylate Flowables

Objectives: The goal of this study was to compare the polymerization-induced cusp deformation by an experimental Silorane flowable composite and conventional methacrylate flowable composites in a tooth cavity model.

Materials and methods: Slot-shaped cavities (8mm x 2mm x 2.5mm) were prepared in aluminium blocks (8mm x 8mm x 15mm), with the thinner cavity wall having a thickness of 2mm. Aluminium was chosen in order to eliminate the variation inherent in natural teeth, and because of its elastic modulus (70GPa) comparable to enamel. The cavities were bulk-filled with X-Flow (XF, Dentsply), Venus Flow (VF, Heraeus Kulzer), Tetric EvoFlow (TEF, Ivoclar-Vivadent), experimental Silorane Flow (SF, 3M ESPE) after pre-treatment with appropriate adhesives. The specimens (n=3-5 per material) were light-cured (60s, Elipar Freelight 2, 3M ESPE) and the dimensional change was recorded until 1h after cure with a Linear Variable Displacement Transducer placed on the thinner cavity wall.

Results: The following table shows the cusp deformation (µm) after 1h. Standard deviations are given in parentheses. All data were analyzed by ANOVA and multiple comparisons using the Tukey test (p<0.05). Means with the same superscripted letters are statistically the same.

Conclusion: Multiple statistically significant differences were found. The experimental Silorane Flow showed the lowest polymerization-induced cusp deformation of all materials tested.