3D Digital Image Correlation Analysis of Local Deformation Field of Different Endodontic Calcium Silicate Cements

Abstract

The objective was to compare the strain of three calcium silicate cements using an optical system based on the 3D digital image correlation method (3D-DIC). Dentine disks from 30 upper premolars were sectioned transversely to obtain 2 mm-thick sections and enlarged with a 4 mm diameter bur. An additional 30 samples were made in Teflon molds (4 × 2 mm). Dentine discs and Teflon molds were divided into three groups with ten samples each and then filled with MTA+ (Cerkamed), Biodentine (Septodont) and Well-Root PT (Vericom). The strain was determined using the 3D-DIC method in two zones: the peripheral and central zones. Data were analyzed using ANOVA with Scheffe’s post hoc test, a paired t-test and Pearson correlation (α = 0.05). Analysis showed that there were significant differences in the values of deformation between all tested materials in both zones. Comparing the strain in both zones, there were significant differences between zones in the Biodentin and Well-Root PT group on dentine discs, and in the Biodentine and MTA group on Teflon discs. Comparing the strain measured on different disc types, the higher values were found on Teflon. All the examined calcium silicate-based cements showed deformation after initial setting. The highest strain was recorded for Biodentine and the lowest was for Well-Root PT.

Keywords

• strain
• deformation field
• calcium silicate
• image processing
• three-dimensional
• digital image correlation method