Related Experiment Video
Updated: May 24, 2026

Shrinkage of Dental Composite in Simulated Cavity Measured with Digital Image Correlation
Published on: July 21, 2014
A method to investigate the shrinkage stress developed by resin-composites bonded to a single flat surface
Lucas V S Pabis1, Tathy A Xavier, Ecinele F Rosa
1Department of Dental Materials, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
Objectives:
To purpose a method for predicting the shrinkage stress development in the adhesive layer of resin-composite cylinders that shrink bonded to a single flat surface, by measuring the deflection of a glass coverslip caused by the shrinkage of the bonded cylinders. The correlation between the volume of the bonded resin-composite and the stress-peak was also investigated.
Methods:
A glass coverslip deflection caused by the shrinkage of a bonded resin-composite cylinder (diameter: d=8 mm, 4 mm, or 2 mm, height: h=4 mm, 2 mm, 1 mm, or 0.5 mm) was measured, and the same set-up was simulated by finite element analysis (3D-FEA). Stresses generated in the adhesive layer were plotted versus two geometric variables of the resin-composite cylinder (C-Factor and volume) to verify the existence of correlations between them and stresses.
Results:
The FEA models were validated. A significant correlation (p<0.01, Pearson's test) between the stress-peak and the coverslip deflection when the resin-composites were grouped by diameter was found for diameters of 2 and 4 mm. The stress-peak of the whole set of data showed a logarithmic correlation with the bonded resin-composite volume (p<0.001, Pearson's test), but did not correlate with the C-Factor.
Significance:
The described method should be considered for standardizing the stress generated by the shrinkage of resin-composite blocks bonded to a single flat surface.
Related Concept Videos
Stress Concentrations
Flexural Stress
Hooke's Law states that within the material's elastic limits, stress is directly proportional to strain. In a member experiencing a bending moment, the strain at any point is relative to its distance...
Shrinkage in Concrete
When concrete is still in its plastic state, it can undergo a decrease in volume by about 1% of its absolute volume. This decrease is known as plastic shrinkage. It arises either...
Distribution of Stresses in a Narrow Rectangular Beam
Residual Stresses in Bending
Residual Stresses

