Akademik Veri Yönetim Sistemi
The 7th international congress on adhesive dentistry, Konya, Türkiye, 1 - 03 Haziran 2023
Fracture behavior of short fiber-reinforced CAD/CAM inlay restorations after aging
Deniz BARLAS1
, Sufyan GAROUSHI2
, Pekka Kalevi VALLITTU2
, Mine Betül ÜÇTAŞLI1
, Lippo LASSILA2
1Department Of Restorative Dentistry, Faculty Of Dentistry, Gazi University, Turkey
2Department Of Biomaterials Science And Turku Clinical Biomaterial Center -Tcbc Institute Of Dentistry, University
Of Turku, Finland
Corresponding Author: barlasdeniiz@gmail.com
Introduction: The aim of this study was to assess the fracture-behavior of molar teeth restored with MOD inlays made of
experimental short fiber-reinforced CAD/CAM composite block (SFRC CAD) before and after cyclic fatigue
aging compared with commercially available hybrid CAD/CAM composites.
Materials and Methods: Standardized MOD cavities were prepared on 60 intact molars by one operator. The teeth were
then randomly distributed into three groups.
A photoimpression of the prepared cavity was taken and then restoration was designed and milled (CEREC, Sirona Dental
Systems Inc) from Cerasmart 270, Enamic and SFRC CAD blocks (n=20/group). All restorations were luted with selfadhesive dual-cure resin cement (G-Cem One). Half of restored teeth per each group (n=10) were statically loaded until
fracture without aging. The remaining half were subjected to cyclic fatigue aging to 500.000 cycles (Fmax=150 N), and then
loaded statically to fracture. Fracture type was then visually examined. SEM and EDS were used to evaluate the
microstructure of CAD/CAM materials. The data were statistically analyzed with 2-way analysis of variance (ANOVA)
followed by Tukey HSD test (α=.05).
Results: ANOVA demonstrated that both material type and aging had a significant effect (p<0.05) on the load-bearing
capacity values of the restorations. Visual analysis of the fracture behavior of the experimental SFRC CAD restorations
revealed that chipping of only tooth structure was predominant. Teeth restored with SFRC CAD showed significantly the
highest (p<0.05) load-bearing capacity (2535±830 N) after fatigue aging among all groups. SEM images showed the ability
of short fibers in SFRC CAD composite to redirect and hinder crack propagation. With regard to fracture mode, Enamic
group revealed 85% of catastrophic failure (vs. 45% and 10% for Cerasmart 270 and SFRC CAD, respectively).
Conclusion: The fracture crack in the experimental SFRC CAD specimens was blocked by discontinuous fibers. Large
MOD cavities on molar teeth were most favorably restored with SFRC CAD inlays, yielding the highest load-bearing
capacity and more restorable failures.
Keywords: CAD/CAM, fatigue aging, inlays, short fiber composite