"Methods:", After calculating the sample size using a statistical formula, twenty eight specimens were fabricated: fourteen first premolar crowns (fracture strength) and fourteen ceramic bars (flexural strength). Crowns were fabricated to fit a preparation following the manufacturer indications. All restorations were cemented. The center of the occlusal surface on each crown per ceramic system was axially loaded to fracture in a universal testing machine (crosshead speed of 5 mm/min). For the bars, three point bending tests were performed using the same testing machine (crosshead speed of 0.5 mm/min). Maximum loads (MPa) were recorded. Fractured mode was examined using a stereomicroscope in order to determine the most prevalent failure for each ceramic system. Statistical analysis was performed using a non parametric Mann-Whitney U test.
"Results:", the results in terms of fracture strength showed no statistical significant difference (p>0.05) between the two all ceramic systems, presenting higher values the Turkom-cera system (1024,9 MPa vs. 824,5 MPa). However, In Ceram system showed higher flexural strength with a statistical significant different (p<0.05). The predominant fracture mode presented for both systems was veneer porcelain and ceramic core together. Only one specimen fractured within the veneer (Turkom-cera).
"Conclusion:", with the limitations of this in-vitro experimental study, it was concluded that both systems have satisfactory fracture strength. However, the use of Turkom cera to fabricate fixed dental prostheses would be not recommended.