The comparison of relative reliability on biaxial and three point flexural strength testing methods of light curing composite resin

Article information

Restor Dent Endod. 2006;31(1):58-65

Publication date (electronic) : 2006 January 31

doi : https://doi.org/10.5395/JKACD.2006.31.1.058

Department of Conservative Dentistry, College of Dentistry, Yonsei University, Korea.

Corresponding Author: Byoung-Duck Roh. Department of Conservative Dentistry, College of Dentistry, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-752, Korea. Tel: 82-2-2228-3146, Fax: 82-2-313-7575, operatys16@yumc.yonsei.ac.kr

Received 2005 August 09; Revised 2005 October 30; Accepted 2005 December 28.

Abstract

The possibility of applying a bi-axial flexure strength test on composite resin was examined using three point and bi-axial flexure strength tests to measure the strength of the light-cured resin and to compare the relative reliability using the Weibull modulus.

The materials used in this study were light-curing restorative materials, MICRONEW™, RENEW® (Bisco, Schaumburg, USA). The bi-axial flexure strength measurements used the piston-on-3-ball test according to the regulations of the International Organization for Standardization (ISO) 6872 and were divided into 6 groups, where the radius of the specimens were 12 mm (radius connecting the 3-balls: 3.75 mm), 16 mm (radius connecting the 3-balls: 5 mm), and the thickness were 0.5 mm, 1 mm, 2 mm for each radius.

The bi-axial flexure strength of the MICRONEW™ and RENEW® were higher than the three point flexure strength and the Weibull modulus value were also higher in all of the bi-axial flexure strength groups, indicating that the bi-axial strength test is relatively less affected by experimental error.

In addition, the 2 mm thick specimens had the highest Weibull modulus values in the bi-axial flexure strength test, and the MICRONEW™ group showed no significant statistical difference (p > 0.05). Besides the 2 mm MICRONEW™ group, each group showed significant statistical differences (p < 0.05) according to the thickness of the specimen and the radius connecting the 3-balls.

The results indicate that for the 2 mm group, the bi-axial flexure strength test is a more reliable testing method than the three point flexure strength test.

Keywords: Biaxial flexure strength; Three point flexure strength; Weibull modulus; Composite resin

References

1. Anusavice KJ, Hojjatie B. Stress distribution in metal ceramic crowns with a facial porcelain margin. J Dent Res 1987. 661493–1498.

2. Zidan O, Asmussen E, et al. Tensile strength of restorative resins. Scand J Dent Res 1980. 88285–289.

3. Bryant RW, Mahler DB. Modulus of elasticity in bending of composites and amalgams. J Prosthet Dent 1986. 56243–248.

4. Radford KC, Lange FF. Loading factors for the biaxial flexure test. J Am Ceram Soc 1978. 61(5-6)211–213.

5. Han BS. Al2O3 selamigseu-ui yeolchunggyeog pagoe geodonggwa yeol-eunglyeog haeseog 1997. Yeonsei Univ. Graduate School; doctorate thesis.

6. Mckinney KR, Herbert CM. Effect of surface finish on structual ceramic failure. J Am Ceram Soc 1970. 53513–516.

7. Kirstein AF, Woolley RM. Symmetrical bending of thin circular elastic plates of equally spaced point supports. J Res Nall Burstds 1967. 71(C)1–10.

8. Kao R, Perrone N, Capps W. Large-deflection solution of the coaxial-ring-circular-glass-plate flexure problem. J Am Ceram Soc 1971. 54566–571.

9. Shetty DK, Roesinfield AR, Duckworth WH, Held PR. A Biaxial-flexure test for evaluating ceramic strength. J Am Ceram Soc 1983. 6636–42.

10. Marshall DB. An improved biaxial flexure test of ceramics. Am Ceram Soc Bull 1980. 59551–553.

11. Lamon J. Statistical approaches to failure for ceramic reliability assessment. J Am Ceram Soc 1988. 71106–112.

12. Wilshaw TR. Measurement of tensile strength of ceramics. J Am Ceram Soc 1968. 51111–117.

13. Park SE. Biaxial fracture behavior and simulation for prediction of fatigue lifetime in alumina by ball-on-3ball test 2000. Yeonsei Univ. Graduate School; doctorate thesis.

14. Shetty DK, Roesinfield AR, Macguire P, Bansal GK, Duckworth WH. Biaxial flexure tests for ceramics. Am Ceram Soc Bull 1980. 59(12)1193–1197.

15. Shetty DK, Roesinfield AR, Bansal GK, Duckworth WH. Biaxial fracture stuies of a glass-ceramic. J Am Ceram Soc 1981. 64(1)1–4.

16. Williams RM, Swank LR. Use of Weibull statics to correlate MOR, Ball-on-ring, and rotational fast fracture tests. J Am Ceram Soc 1983. 66(11)756–768.

17. Ham-Su R, Wilkinson DS. Strength of tape cast and laminated ceramics. J Am Ceram Soc 1995. 78(6)1580–1584.

18. Chiang MYM, Tesk JA. Differences: Hertz vs finite element calculation for diametral tensile strength. J Dent Res 1989. 68341–348.

19. Ban S, Anusavice KJ. Influence of test method on failure stress of brittle dental materials. J Dent Res 1990. 69(12)1791–1799.

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This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Figure 1

Schematic illustration of three point flexure test.

Figure 2

Schematic illustration of piston-on-three-ball bi-axial flexure test.

Figure 3

Weibull modulus graph according to specimen thickness on 3.75 mm supporting ball radius (MICRONEW™, Bisco, Schaumburg, U.S.A.).

Figure 4

Weibull modulus graph according to specimen thickness on 5 mm supporting ball radius (MICRONEW™, Bisco, Schaumburg, U.S.A.).

Figure 5

Weibull modulus graph according to specimen thickness on 3.75 mm supporting ball radius (RENEW®, Bisco, Schaumburg, U.S.A.).

Figure 6

Weibull modulus graph according to specimen thickness on 5 mm supporting ball radius (RENEW®, Bisco, Schaumburg, U.S.A.).

Table 1

Light cured composite resin used in this study

Table 2

Mean flexure strength and Weibull modulus of three point flexure test and biaxial flexure test

If the alphabet is different, significant difference at α= 0.05 (between the thickness on the same diameter).

^*indicates significant difference at α= 0.05 (between the diameter on the same thickness).

Table 3

Mean flexure strength and Weibull modulus of three point flexure test and biaxial flexure test

If the alphabet is different, significant difference at α= 0.05 (between the thickness on the same diameter).

^*indicates significant difference at α= 0.05 (between the diameter on the same thickness).