Related Experiment Video
Updated: Feb 7, 2026

Ultrasonic Welding of Thermoplastic Composite Coupons for Mechanical Characterization of Welded Joints through Single Lap Shear Testing
Published on: February 11, 2016
Influence of a cylindrical crosshead on shear bond testing of composite-tooth interfaces
Chris S Ivanoff1,2, Timothy L Hottel3, Franklin Garcia-Godoy1
1Department of Bioscience Research, College of Dentistry, The University of Tennessee Health Science Center.
Abstract:
The effect of a cylindrical crosshead on shear bond strength of composite to dentin was assessed by finite element analysis (FEA) after shear bond testing thirty mandibular molars restored with composite cylinders (Tetric EvoCeram-3 mm diameter) perpendicular to conditioned dentin. Cross-sectional geometric models were created with quadrilateral linear plane stress elements. Stress distributions for normal, shear, and major principal stresses were plotted. Mean shear bond strength for the experimental group was 23.9 MPa (±4.54), about 15-75% higher than values reported with other methods. FEA showed localized 'hot spots' (±16-20 MPa) at the corners of the base of the adhesive layer under a 20 N vertical load. Principal stresses across the composite-dentin interface were lower (±12-16 MPa), but significantly homogenous, approximating closely the nominal strength value. With uniform stress distributions across the adhesive layer, FEA confirmed that a cylindrical crosshead may be an optional tool to improve shear bond testing of dental materials.
More Related Videos
Related Concept Videos
Bond Energies and Bond Lengths
Protein-protein Interfaces
Peptide Bonds
Bonding in Metals
Ionic Bonds
When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions with opposite charges. Ionic compounds are rigid and brittle when solid and may dissociate into their constituent ions in water. Covalent compounds, by contrast, remain intact unless a chemical reaction breaks them.
Opposing Charges Hold Ions Together in Ionic Compounds
Ionic bonds are reversible electrostatic interactions between ions...
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...

