Fracture load and microcrack comparison of crowns manufactured from tooth-shaped and traditional blocks

Arslan M., TOSUN İ.

MICROSCOPY RESEARCH AND TECHNIQUE, vol.84, no.1, pp.111-118, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 84 Issue: 1
  • Publication Date: 2021
  • Doi Number: 10.1002/jemt.23571
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), Biotechnology Research Abstracts, CAB Abstracts, Communication Abstracts, EMBASE, MEDLINE, Metadex, Veterinary Science Database, Civil Engineering Abstracts
  • Page Numbers: pp.111-118
  • Çanakkale Onsekiz Mart University Affiliated: Yes


This study intended to analyze microcracks and fractographic markings on the surface of all ceramic crowns after milling and compare the fracture loads. 90 crowns were manufactured from two feldspathic (Priticrown-Pr and Vita Mark II-Vi) and a lithium disilicate (EmaxCAD-Em) blocks (n= 30). Two groups (n= 15) were prepared for each ceramic. In the first group, crowns were analyzed twice via the fluorescent penetrant method for microcrack detection, after the manufacturing process and thermal cycles. The load to fracture test was applied at a crosshead speed of 0.5 mm/min until catastrophic failure. Second group crowns were directly cemented onto the Co-Cr dies following the manufacturing process and loaded to fracture. Fractographic markings were analyzed through scanning electron microscope. Spearman correlation analysis, Kruskal-WallisHtest, Mann-WhitneyUtest, and Wilcoxon Signed Rank test were applied (alpha= .05). Fracture loads of Em crowns were higher than other groups (p <.05), with and without the aging procedure. Except for second group Pr (r= -.532), no significant relationship was found between microcrack numbers and fracture loads (p > .05). Thermal cycling did not affect microcrack numbers and fracture loads (p > .05). Tooth-shaped multilayered Pr blocks did not provide an advantage in terms of microcrack and fracture loads.