Related Experiment Video
Updated: Aug 21, 2026

Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
Effects of bonded composites vs. amalgam on resistance to cuspal deflection for endodontically-treated premolar teeth
Antonio Cerutti1, Piera Flocchini, Lorenzo Madini
1Department of Restorative Dentistry, School of Dentistry, University of Brescia, P. le Spedali Civili 1, 25123 Brescia, Italy. cerant@tin.it
Purpose:
To determine, by means of a non-destructive experimental procedure, the extent to which tooth cusps are weakened by endodontic procedures and the effectiveness of adhesive bonding restoration in reducing cuspal deflection as a function of different restorative procedures.
Methods:
A mechanically controlled loading device induced cuspal deflection by axial force (range 98-294 N) on an occlusal surface while LTS laser twin sensors registered the amount of deflection. Cusp deflection values, in microns, were recorded for each tooth. Thirty sound maxillary premolars teeth were sequentially evaluated in the following conditions: A) intact tooth; B) completion of endodontic and restorative procedures. Teeth were randomly divided into five groups and restored respectively with: A) amalgam (Dispersalloy); B) Spectrum TPH; C) Surefil; D) Esthet-X; E) Esthet-X + Dyract Flow.
Results:
The average loading force needed to induce 1 microm cusp deflection was evaluated, for all groups, in intact teeth (range 49.52-58.76 N/microm) and in restored teeth (range 8.56 - 47.05 N/microm). Statistical analysis (ANOVA for repeated measures) has been performed. Mean structural recovery values after restorative treatment were 17% with amalgam, 60% with Spectrum TPH, 59% with SureFil, 54% with Esthet-X, and 99% with Esthet-X/Dyract.
