Stress analysis of zirconia abutment

Objectives:

The purpose of this study was to conduct the stress analysis of the zirconia abutment compared with the titanium abutment.

Methods:

The GENESiO (GC ) was applied as an implant system in this study.

The abutment, the implant body and the abutment screw were modelled with 3D CAD (SolidWorks) in order to compare the results of real mechanical test with those of FEM (finite element method / COSMOS Works Designer) analysis.

On 3D CAD, the implant body was fixed in a condition of osseointegration and the abutment was tightened by an abutment screw with recommended torque.

The modelled data were analyzed with two kinds of tests by FEM.

Test1: A compression-loading test (25° to the implant axis)

Test2: A repetition durability test (5,000,000 times, 25kgf, 25° to the implant axis)

The materials of the abutment were postulated as titanium and zirconium for FEM analysis.

The real mechanical test with the same condition as Test1 and 2 was conducted and compared with the results of FEM analysis.

Results:

Test1:

In the real mechanical test, breaking load of the zirconia abutment resulted in 51.1kgf.

Contrastingly, the titanium abutment was bent with the almost same load (One-way ANOVA, p>0.05).

Breaking (Bending) load (kgf)

	FEM analysis	Real mechanical test
Zirconia	51.0	51.1 (1.8) Breaking
Titanium	56.1	52.6 (3.1) Bending

Test2: Neither abutment was broken by FEM analysis. The same result was provided by the real mechanical test.

In addition, the results of FEM analysis were equal with those of real mechanical test (One-way ANOVA, p>0.05).

Conclusion:

The zirconia abutment had the approximately same mechanical strength with the titanium abutment and it could be applied clinically with the same design as the titanium abutment.