Title: 0585 - Silane Influence on PICN Interfacial Fracture Toughness With Resin Cement


Maher Eldafrawy (Presenter)
University of Liège (ULiège)

Laura Greimers, University of Liège (ULiège)
Sandrine Bekaert, University of Liège (ULiège)
Patrick Gailly, University of Liège (ULiège)
Cédric Lenaerts, University of Liège (ULiège)
Jean-François Nguyen, Université Paris Diderot
Michael Sadoun, MaJEB sprl
Amélie Mainjot, University of Liège (ULiège)


Objectives: To evaluate the influence of silane on Interfacial Fracture Toughness (IFT) of composite cement with two sub-classes of CAD-CAM composites, polymer-infiltrated ceramic network (PICN) and dispersed filler (DF), after etching or gritblasting. Secondary objectives were to correlate results with developed interfacial area ratio (Sdr) and surface wettability.

Methods: Experimental PICN blocks were prepared by partially sintering Vita Mark II glass-ceramic powder (73.8-vol%) then infiltrating it under vacuum with UDMA and polymerizing it under high temperature-pressure (HT-HP) at 180°C-300MPa. Experimental DF blocks were composed of 70.4-wt% fillers in a matrix of UDMA and TEGDMA polymerized under HT-HP. Blocks were cut and polished into equilateral half prisms (6.0±0.1-mm) and pre-treated with either 5% hydrofluoric acid (HF) or gritblasting with 50-µm Al2O3 particles, then bonded to their counterparts with an experimental light-cure resin cement, adjusted at 50-µm thickness using a custom-built device, either with or without an experimental silane (n=30 per group). All samples were subjected to thermocycling (10,000 cycles) and tested for IFT using the Notchless Triangular Prism test in a water bath at 36°C. Moreover, rectangular samples of each group, in addition to samples of Vita Mark II and pure UDMA receiving the same surface pre-treatments, were examined for contact angle measurement (n=15 per group), and Sdr by profilometry (n=5 per group).

Results: PICN-HF with silane gave the highest IFT significantly compared to all the other groups. Three-way ANOVA revealed the influence of silane, material class, surface pre-treatment and all combined on IFT (p<0.05). When silane was used, IFT was shown to be correlated with Sdr (r2=0.84), while surface wettability was increased. PICN gave better results when etched and DF when gritblasted.

Conclusions: This study highlighted the importance of silane pre-treatment on PICN bonding effectiveness. Results suggest that silane enhances bond micromechanical interlocking by increasing surface wettability and consequently resin penetration in surface micro-porosities.

Student Presenter

Disclosure Statement:
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE