:: Volume 27, Issue 4 (10-2015) ::
J Iran Dent Assoc 2015, 27(4): 168-172 Back to browse issues page
Shear Bond Strength of Composite to Dentin following Light Curing with Light Emitting Diode and Quartz Tungsten Halogen Light Curing Units
Mansoreh Mirzaee1, Esmaeil Yassini *2, Mohammad Javad Kharazifard3, Mehrnaz Vaziri4
1- Assosiated Professor, Dental Research Center, Dentistry Research Institute, Department of Restorative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
2- Professor, Dental Research Center, Dentistry Research Institute, Department of Restorative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran , denthstry@tums.ac.ir
3- Research Member, Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran
4- Dentist, Private Office, Ahvaz, Iran
Abstract:   (3232 Views)

Background and Aim: The use of light emitting diode (LED) light curing units has recently increased due to optimal properties such as longer durability, no need for filter and less heat generation compared to quartz tungsten halogen (QTH) devices. The aim of this study was to assess the shear bond strength of composite to dentin following lightcuring with QTH and LED light curing units for different time periods.

Materials and Methods: In this experimental study, 60 sound extracted human molar and premolar teeth with no decay or restorations were collected. The buccal surface of the teeth was ground to expose adequate amount of dentin. The teeth were randomly divided into six groups. After acid etching and bonding, composite was packed in plastic cylindrical molds and placed on dentin surface. Groups one, two and three were cured by a LED unit (Wood Pecker) with ramp method for 20, 30 and 40 seconds, respectively. Groups four, five and six were cured with a QTH unit (Optilux 501) with a light intensity of 500 mW/cm2 for 20, 30 and 40 seconds, respectively. After keeping the samples for two weeks in distilled water at room temperature, shear bond strength was measured by a universal testing machine at a crosshead speed of 1mm/minute. The data were analyzed by Two-way ANOVA, one-way ANOVA and Tukey’s HSD test.

Results: One-way ANOVA showed a significant difference among the groups and the mean shear bond strength was the highest following light curing by LED device for 40 seconds (18.63 MPa). Pairwise comparisons by Tukey’s test showed significant differences in shear bond strength of groups cured with LED unit (P= 0.059 for the difference between 20 seconds and 40 seconds and P=0.004 for the difference between 30 seconds and 40 seconds).

Conclusion: Use of LED units (ramp method) yielded superior results in terms of shear bond strength compared to QTH. Also, 40 seconds of curing is recommended in use of LED devices.

Keywords: Shear Strength, Composite Resins, Curing Lights, Dental
Full-Text [PDF 152 kb]   (1513 Downloads)    
Type of Study: Orginal | Subject: Restorative Dentistry
1. Hervás-García A, Martínez-Lozano MA, Cabanes-Vila J, Barjau-Escribano A, Fos-Galve P. Composite resins. A review of the materials and clinical indications. Med Oral Patol Oral Cir Bucal. 2006 Mar 1;11(2):E215-20.
2. He Z, Shimada Y, Tagami J. The effects of cavity size and incremental technique on micro-tensile bond strength of resin composite in ClassI cavities. Dent Mater. 2007 May;23(5):533-8.
3. T. P. Rodrigues, A. N. S. Rastelli, M. F. Andrade, J.R.C. Saad. Effect of different dental composite resins on the polymerization process. Laser physics. 2009 Dec; 19:2224.
4. Theodore M, Roberson Harald O, Heymann Edward J, Swift Jr. Sturdevant's art and science of operative dentistry, 5th Ed. MOSBY Elsevier Health Sciences, 2006.
5. Bala O, Olmez A, Kalayci S. Effect of LED and halogen light curing on polymerization of resin based composites. J Oral Rehabil; 2005 Feb; 32 (2):134-40.
6. L.R. Calixto, D.M. Lima, R.S. Queiroz, A.N.S. Rastelli, V.S. Bagnato, M.F. Andrade. Curing depth of composite resin light cured by LED and halogen light-curing units. Laser physics; 2008; 18 (11):1365-1369.
7. Fernanda Regina Voltarelli, Claudia Batitucci dos Santos-Daroz, Marcelo Corrêa Alves, Alessandra Rezende Peris, Giselle Maria Marchi. Effect of different light-curing devices and aging procedures on composite knoop mi-crohardness. Braz Oral Res. 2009 Oct-Dec; 23(4):473-479.
8. Uzel A, Buyukyilmaz T, Kayalioglu M, Uzel I. Temperature Rise During Orthodontic Bonding With Various Light-curing Units-an In Vitro Study. Angle Orthod. 2006 Mar;76(2):330-4.
9. Yazici AR, Müftü A, Kugel G, Perry RD. Comparison of temperature changes in the pulp chamber induced by various light curing units, in vitro. Oper Dent. 2006 Mar-Apr;31(2):261-5.
10. Luis Felipe J Schneider, Rafael R de Moraes, Mário Alexandre C Sinhoreti, Lourenço C Sobrinho, Simonides Consani. Temperature rise and Knoop hardness promoted by different light-curing units. Braz Dent Sci. 2008 Jan-March; 11 (1(:6-12.
11. Knobloch L, Kerby RE, Clelland N, Lee J. Hardness and degree of conversion of posterior packable composites. Oper Dent. 2004 Nov-Dec; 29(6):642-9.
12. Yap AU, Soh MS. Curing efficacy of a new generation high – power LED lamp. Oper Dent. 2005 Nov-Dec;30(6):758-763.
13. Oberholzer TG, Du Preez IC, Kidd M. Effect of LED curing on the microleakage, shear bond strength and surface hardness of a resin-based composite restoration. Biomaterials. 2005 Jun; 26 (18):3981-3986.
14. Lin CP, Douglas WH. Failure mechanisms at the human dentin-resin interface: A fracture mechanics approach. J Biomech. 1994 Aug; 27(8): 1037–47.
15. Nomoto R, McCabe JF, Hirano S. Comparison of halogen, plasma and LED curing units. Oper Dent. 2004 May-Jun;29(3):287-94.
16. Korkmaz Y, Attar N. Dentin bond strength of composites with self-etching adhesives using LED curing lights. J Contemp Dent Pract. 2007 Jul; 1; 8 (5):34-42.
17. Leonard DL, Charlton DG, Roberts HW, Cohen ME. Polymerization efficiency of LED curing lights. J Esthet Restor Dent. 2002; 14(5): 286-95.
18. Price RB, Felix CA, Andreou P. Evaluation of a second-generation LED curing light. J Can Dent Assoc. 2003 Nov;69(10):666.

XML     Print

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Volume 27, Issue 4 (10-2015) Back to browse issues page