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The effect of intermittent composite curing on marginal adaptation

The effect of intermittent composite curing on marginal adaptation

Article information

Restor Dent Endod. 2007;32(3):248-259
Publication date (electronic) : 2007 May 31
doi : https://doi.org/10.5395/JKACD.2007.32.3.248
Department of Conservative Dentistry, The Gaduate School, Yonsei University, Korea.
Corresponding Author: Sung-Ho Park. Department of Conservative Dentistry, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul, Korea, 120-752. Tel: 82-2-2228-3147, Fax: 82-2-361-7575, sunghopark@yumc.yonsei.ac.kr
Received 2007 March 28; Revised 2007 April 20; Accepted 2007 April 30.

Abstract

The aim of this research was to study the effect of intermittent polymerization on marginal adaptation by comparing the marginal adaptation of intermittently polymerized composite to that of continuously polymerized composite.

The materials used for this study were Pyramid (Bisco Inc., Schaumburg, U.S.A.) and Heliomolar (Ivoclar Vivadent, Liechtenstein). The experiment was carried out in class II MOD cavities prepared in 48 extracted human maxillary premolars. The samples were divided into 4 groups by light curing method; group 1- continuous curing (60s light on with no light off); group 2- intermittent curing (cycles of 3s with 2s light on & 1s light off for 90s); group 3- intermittent curing (cycles of 2s with 1s light on & 1s light off for 120s); group 4- intermittent curing (cycles of 3s with 1s light on & 2s light off for 180s). Consequently the total amount of light energy radiated was same in all the groups. Each specimen went through thermo-mechanical loading (TML) which consisted of mechanical loading (720,000 cycles, 5.0 kg) with a speed of 120 rpm for 100 hours and thermocycling (6000 thermocycles of alternating water of 50℃ and 55℃). The continuous margin (CM) (%) of the total margin and regional margins, occlusal enamel (OE), vertical enamel (VE), and cervical enamel (CE)) was measured before and after TML under a × 200 digital light microscope.

Three-way ANOVA and Duncan's Multiple Range Test was performed at 95% level of confidence to test the effect of 3 variables on CM (%) of the total margin: light curing conditions, composite materials and effect of TML. In each group, One-way ANOVA and Duncan's Multiple Range Test was additionally performed to compare CM (%) of regions (OE, VE, CE).

The results indicated that all the three variables were statistically significant (p < 0.05). Before TML, in groups using Pyramid, groups 3 and 4 showed higher CM (%) than groups 1 and 2, and in groups using Heliomolar, groups 3 and 4 showed higher CM (%) than group 1 (p < 0.05). After TML, in both Pyramid and Heliomolar groups, group 3 showed higher CM (%) than group 1 (p < 0.05). CM (%) of the regions are significantly different in each group (p < 0.05). Before TML, no statistical difference was found between groups within the VE and CE region. In the OE region, group 4 of Pyramid showed higher CM (%) than group 2, and groups 2 and 4 of Heliomolar showed higher CM (%) than group 1 (p < 0.05). After TML, no statistical difference was found among groups within the VE and CE region. In the OE region, group 3 of Pyramid showed higher CM (%) than groups 1 and 2, and groups 2,3 and 4 of Heliomolar showed higher CM (%) than group 1 (p < 0.05).

It was concluded that intermittent polymerization may be effective in reducing marginal gap formation.

References

1. Burke FJ. Light-activated composites. the current status. Dent Update 1985. 12182184–188.
2. Feilzer AJ, De Gee AJ, Davidson CL. Curing contraction of composites and glass ionomer cements. J Prosthet Dent 1988. 59297–300.
3. Carvalho RM, Pereira JC, Yoshiyama M, Pashley DH. A review of polymerization contraction: The influence of stress development versus stress relief. Oper Dent 1996. 2117–24.
4. Hansen EK. Visible light-cured composite resins: polymerization contraction, contraction pattern and hygroscopic expansion. Scand J Dent Res 1982. 90(4)329–335.
5. Suliman AA, Boyer DB, Lakes RS. Cusp movement in premolars resulting from composite polymerization shrinkage. Dent Mater 1993. 01. 96–10.
6. Unterbrink GL, Muessner R. Influence of light intensity on two restorative system. J Dent 1995. 23183–189.
7. Goracci G, Mori G, De Martinis LC. Curing light intensity and marginal leakage of resin composite restorations. Quintessence Int 1996. 27355–362.
8. Mehl A, Hickel R, Kunzelmann KH. Physical properties and gap formation of a light-cured composites with and without 'softstart-polymerization'. J Dent 1997. 25321–330.
9. Kanca J 3rd, Suh BI. Pulse activation. Reducing resin-based composite contraction stresses at the enamel cavosurface margins. Am J Dent 1999. 12107–112.
10. Alonso RC, Cunha LG, Correr GM. Association of photoactivation methods and low modulus liners on marginal adaptation of composite restoration. Acta Odontol Scand 2004. 62298–304.
11. Rueggeberg F. Contemporary issues in photocuring. Compend Contin Educ Dent Suppl 1999. (25)S4–S15.
12. Obici AC, Sinhoreti MAG, Goes MF, Consani S, Sobrinho LC. Effect of photo-activation method on polymerization shrinkage of restorative composites. Oper Dent 2002. 27192–198.
13. Kim MK, Lee CY. Effect of intermittent polymerization on the rate of polymerization shrinkage, microhardness and cuspal deflection in composite resin 2005. Yonsei University; PhD thesis.
14. Lee SY, Park SH. Measurements of shrinkage stress and reduction of inter-cuspal distance in maxillary premolars resulting from polymerization of composites and compomers. J Korean Acad Conserv Dent 2004. 29346–352.
15. Krejci I, Lutz F, Reimer M. Marginal adaptation and fit of adhesive ceramic inlays. J Dent 1993. 2139–46.
16. Park SH, Jung IY, Lee KY. Development of chewing simulator. J Korean Acad Conserv Dent 2003. 2834–40.
17. Luescher B, Lutz F. Obschenbein H and Muehlemann HR: Microleakage and marginal adaptation in conventional and adhesive class II restorations. J Prosthet Dent 1977. 37300–309.
18. Dietschi D, Bindi G. Marginal and internal adaptation of stratified compomer-compostie class II restorations. Oper Dent 2002. 27500–509.
19. Choi IB, Park SH. Marginal adaptation of indirect composite resin systems in three different base materials 2003. Yonsei University; MD thesis.
20. Feilzer AJ, De Gee AJ, Davidson CL. Quantitative determination of stress reduction by flow in composite restorations. Dent Mater 1990. 6167–171.
21. Davidson CL, de Gee AJ. Relaxation of polymerization contraction stress by flow in dental composites. J Dent Res 1984. 63146–148.
22. Uno S, Asmussen E. Marginal adaptation of restorative resin polymerized at reduced rate. Scand J Dent Res 1991. 99440–444.
23. Davidson CL, Feilzer AJ. Polymerization shrinkage and polymerization shrinkage stress in polymer-based restoratives. J Dent 1997. 25435–440.
24. Alvarez-Gayosso C, Barcelo-Santana F, Guerrero-Ibarra J, Saes-Espinola G, Canseco-Martinez MA. Calculation of contraction rates due to shrinkage in light-cured composites. Dent Mater 2004. 20(3)228–235.
25. Shimada Y, Tagami J. Effects of regional enamel and prism orientation on resin bonding. Oper Dent 2003. 2820–27.
26. Jung W, Park SH. The effect of additional etching on the marginal adaptation of self etching adhesives; evaluation through thermo-mechanical loading 2005. Yonsei University; MD thesis.

Article information Continued

Figure 1

Schematic drawing of cavity preparation.

Figure 2

Upper view of the shutter appliance.

Figure 3

Metallic fixer with a tooth (R&B, Daejeon, Korea).

Figure 4

Gap on margin between the tooth and the resin (× 200).

Figure 5

Continuous margin between the tooth and the resin (× 200).

Figure 6

Chewing simulator (R&B, Daejeon, Korea).

Figure 7

Experimental procedures.

Figure 8

Marginal adaptations before loading in the regions (Pyramid).

T: total margin, OE: occlusal enamel margin, VE: vertical enamel margin, CE: cervical enamel margin

The letters represent the results of Duncan's Multiple Range Test.

Figure 9

Marginal adaptations before loading in the regions (Heliomolar).

T: total margin, OE: occlusal enamel margin, VE: vertical enamel margin, CE: cervical enamel margin

The letters represent the results of Duncan's Multiple Range Test.

Figure 10

Marginal adaptations after loading in the regions (Pyramid).

T: total margin, OE: occlusal enamel margin, VE: vertical enamel margin, CE: cervical enamel margin

The letters represent the results of Duncan's Multiple Range Test.

Figure 11

Marginal adaptations after loading in the regions (Heliomolar).

T: total margin, OE: occlusal enamel margin, VE: vertical enamel margin, CE: cervical enamel margin

The letters represent the results of Duncan's Multiple Range Test.

Table 1

Restorative materials used in this study

Table 1

Table 2

List of investigated photoactivation methods with their curing cycles

Table 2

Table 3

Three-way ANOVA for 3 variables

Table 3

a): before or after TML (thermo-mechanical loading)

b): Pyramid or Heliomolar

Table 4

Mean total CM (%) of each group and DMR Grouping

Table 4

CM: continuous margin, DMR: Duncan's Multiple Range Test, TML: thermo-mechanical loading

*: statistically significant difference between Pyramid and Heliomolar (p < 0.05).

Table 5

Mean CM (%) of tooth regions and DMR Grouping (Pyramid)

Table 5

T: total margin, OE: occlusal enamel, VE: vertical enamel, CE: cervical enamel

DMR: Duncan's Multiple Range Test

Table 6

Mean CM (%) of tooth regions and DMR Grouping (Heliomolar)

Table 6

T: total margin, OE: occlusal enamel, VE: vertical enamel, CE: cervical enamel

DMR: Duncan's Multiple Range Test