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Comparative fracture strength analysis of Lava and Digident CAD/CAM zirconia ceramic crowns.

Kwon TK, Pak HS, Yang JH, Han JS, Lee JB, Kim SH, Yeo IS - J Adv Prosthodont (2013)

Bottom Line: To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns.A metal die was also duplicated from the original prepared tooth for fracture testing.The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain.

View Article: PubMed Central - PubMed

Affiliation: Department of Dentistry, St. Catholic Hospital, Catholic University of Korea, Suwon, Republic of Korea.

ABSTRACT

Purpose: All-ceramic crowns are subject to fracture during function. To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns. The aim of this study was to compare the fracture strengths of two computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia crown systems: Lava and Digident.

Materials and methods: Twenty Lava CAD/CAM zirconia crowns and twenty Digident CAD/CAM zirconia crowns were fabricated. A metal die was also duplicated from the original prepared tooth for fracture testing. A universal testing machine was used to determine the fracture strength of the crowns.

Results: THE MEAN FRACTURE STRENGTHS WERE AS FOLLOWS: 54.9 ± 15.6 N for the Lava CAD/CAM zirconia crowns and 87.0 ± 16.0 N for the Digident CAD/CAM zirconia crowns. The difference between the mean fracture strengths of the Lava and Digident crowns was statistically significant (P<.001). Lava CAD/CAM zirconia crowns showed a complete fracture of both the veneering porcelain and the core whereas the Digident CAD/CAM zirconia crowns showed fracture only of the veneering porcelain.

Conclusion: The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain.

No MeSH data available.


Related in: MedlinePlus

Schematic view of the fracture strength determination procedure with CAD/CAM zirconia crowns. The direction of the load applied was 30°, and the loading points were consistently maintained by repositioning the metal die.
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Figure 2: Schematic view of the fracture strength determination procedure with CAD/CAM zirconia crowns. The direction of the load applied was 30°, and the loading points were consistently maintained by repositioning the metal die.

Mentions: A universal testing machine (STM-5; United Calibration Corp., Huntington Beach, CA, USA) was used for the fracture strength test. The load was applied to the lingual fossa at 30 degrees to the long axis of the specimen until catastrophic failure occurred (Fig. 2). Catastrophic failure was defined as exhibition of visible cracks, load drops and acoustic events of chipping or fracture. Each specimen was positioned and fixed in a matrix to maintain identical loading position and angle during the fracture strength test. The force was applied to the artificial crown with a 5 mm diameter spherical steel rod at a crosshead speed of 1 mm per minute.


Comparative fracture strength analysis of Lava and Digident CAD/CAM zirconia ceramic crowns.

Kwon TK, Pak HS, Yang JH, Han JS, Lee JB, Kim SH, Yeo IS - J Adv Prosthodont (2013)

Schematic view of the fracture strength determination procedure with CAD/CAM zirconia crowns. The direction of the load applied was 30°, and the loading points were consistently maintained by repositioning the metal die.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3675299&req=5

Figure 2: Schematic view of the fracture strength determination procedure with CAD/CAM zirconia crowns. The direction of the load applied was 30°, and the loading points were consistently maintained by repositioning the metal die.
Mentions: A universal testing machine (STM-5; United Calibration Corp., Huntington Beach, CA, USA) was used for the fracture strength test. The load was applied to the lingual fossa at 30 degrees to the long axis of the specimen until catastrophic failure occurred (Fig. 2). Catastrophic failure was defined as exhibition of visible cracks, load drops and acoustic events of chipping or fracture. Each specimen was positioned and fixed in a matrix to maintain identical loading position and angle during the fracture strength test. The force was applied to the artificial crown with a 5 mm diameter spherical steel rod at a crosshead speed of 1 mm per minute.

Bottom Line: To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns.A metal die was also duplicated from the original prepared tooth for fracture testing.The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain.

View Article: PubMed Central - PubMed

Affiliation: Department of Dentistry, St. Catholic Hospital, Catholic University of Korea, Suwon, Republic of Korea.

ABSTRACT

Purpose: All-ceramic crowns are subject to fracture during function. To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns. The aim of this study was to compare the fracture strengths of two computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia crown systems: Lava and Digident.

Materials and methods: Twenty Lava CAD/CAM zirconia crowns and twenty Digident CAD/CAM zirconia crowns were fabricated. A metal die was also duplicated from the original prepared tooth for fracture testing. A universal testing machine was used to determine the fracture strength of the crowns.

Results: THE MEAN FRACTURE STRENGTHS WERE AS FOLLOWS: 54.9 ± 15.6 N for the Lava CAD/CAM zirconia crowns and 87.0 ± 16.0 N for the Digident CAD/CAM zirconia crowns. The difference between the mean fracture strengths of the Lava and Digident crowns was statistically significant (P<.001). Lava CAD/CAM zirconia crowns showed a complete fracture of both the veneering porcelain and the core whereas the Digident CAD/CAM zirconia crowns showed fracture only of the veneering porcelain.

Conclusion: The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain.

No MeSH data available.


Related in: MedlinePlus