The Journal of Contemporary Dental Practice

Register      Login

SEARCH WITHIN CONTENT

FIND ARTICLE

Volume / Issue

Online First

Archive
Related articles

VOLUME 11 , ISSUE 5 ( October, 2010 ) > List of Articles

RESEARCH ARTICLE

Effects of Load Cycling on the Microleakage of Beveled and Nonbeveled Margins in Class V Resin-Based Composite Restorations

Hamideh Ameri, Marjaneh Ghavamnasiri, Ehsan Abdoli

Citation Information : Ameri H, Ghavamnasiri M, Abdoli E. Effects of Load Cycling on the Microleakage of Beveled and Nonbeveled Margins in Class V Resin-Based Composite Restorations. J Contemp Dent Pract 2010; 11 (5):25-32.

DOI: 10.5005/jcdp-11-5-25

License: CC BY-NC 3.0

Published Online: 01-10-2010

Copyright Statement:  Copyright © 2010; Jaypee Brothers Medical Publishers (P) Ltd.


Abstract

Aim

This study evaluated the influence of mechanical loading and thermocycling on microleakage of class V resin-based composite restorations with and without enamel bevel.

Methods and Materials

Sixty class V cavity preparations measuring 3.0 mm wide (mesiogingivally) x 2.0 mm high (occluso-gingivally) x 1.5 mm deep with the occlusal margin in enamel and the gingival margin in cementum were prepared on the buccal surfaces of human premolars using a #12 diamond round bur (Drendel & Zweiling Diamant GmbH, Lemgo, Germany) in a high-speed, water-cooled handpiece. The specimens were then divided into two groups of 30 specimens each, based on the type of enamel cavosurface margin configuration as beveled or nonbeveled (butt joint). After restoring the preparations with a flowable resin-based composite (Tetric Flow, Ivoclar Vivadent-AG, Schaan, Liechtenstein) and finishing and polishing with sequential discs (Sof-Lex Pop-on, 3M-ESPE, St. Paul, MN, USA), the teeth were stored at 37°C and 100 percent humidity. Twenty-four hours later, half of the specimens in each group (nonbeveled “N” or beveled “B”) were exposed to a cycling loading for 250,000 cycles to simulate occlusal loading and assigned to two subgroups (NL+ or BL+), while the remainder of the specimens in each group were only maintained in a 100-percent-humidity environment, without any cyclical loading, until tested (NL– or BL–). The specimens were sealed with sticky wax (Kemdent, Associated Dental Products, Swindon, UK) and nail polish. The apical foramen of each tooth was sealed with sticky wax and the rest of the tooth was covered with nail varnish, except for an area within 1.0 mm around the composite restoration. To detect marginal leakage, all of the samples were stored in a 0.5 percent basic fuchsine solution for 24 hours. The specimens were then sectioned longitudinally using a low-speed diamond blade (IsoMet, Buehler Ltd., Lake Bluff, IL, USA), machined, and evaluated under 25X magnification using a stereomicroscope (M9, Wild Heerbrugg, Switzerland). The specimens were scored on a scale from 1 to 4 on the degree of dye penetration. The qualitative data were analyzed by the Mann- Whitney U test at a 5 percent significance level (p<0.05). The null hypothesis of this study was that there is no difference in microleakage between beveled and nonbeveled class V buccal preparations in premolar teeth restored with resinbased composite and subjected to simulated occlusal loading and thermocycling.

Results

In each group the gingival margin showed significantly more microleakage than the enamel margin (p<0.05). Load cycling did not result in an increase in microleakage in nonbeveled (p=0.259) or in beveled (p=0.053) occlusal margins. However, the gingival margins showed a statistically significant difference in microleakage after load cycling whether in cavities with enamel occlusal bevel (p=0.004) or in groups without a bevel. This means the enamel margin configuration of the enamel occlusal margin had no effect on decreasing microleakage in the gingival aspect of class V composite restorations. In general, the nonbeveled preparations in this study had significantly less microleakage than the bevel specimens whether they were loaded occlusally or not (p=0.001).

Clinical Significance

Within the limitations of this in vitro study, no benefit was derived from placing an enamel cavosurface bevel on the occlusal margin of a standardized class V composite restoration located at the cementoenamel junction. The most important consideration is to prevent microleakage along the gingival margin regardless of whether the occlusal enamel margin is beveled.

Citation

Ameri H, Ghavamnasiri M, Abdoli E. Effects of load cycling on the microleakage of beveled and nonbeveled occlusal margins in class V resin-based composite restorations. J Contemp Dent Pract [Internet]. 2010 October; 11(5):025- 032. Available from: http://www.thejcdp.com/ journal/view/volume11-issue5-ghavamnasiri


PDF Share
  1. Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent. 2003;28(3):215–35.
  2. Marginal adaptation in vitro and clinical outcome of Class V restorations. Dent Mater. 2009; 25(5):605-20.
  3. Effect of material properties of composite restoration on the strength of the restoration–dentine interface due to polymerization shrinkage, thermal and occlusal loading. Med Eng Phys. 2007; 29(6):671-6.
  4. Effect of elastic cavity wall and occlusal loading on microleakage and dentin bond strength. Oper Dent. 2007; 32(5):466-75.
  5. The effect of load cycling on the nanoleakage of dentin bonding systems. Dent Mater. 2002; 18(2):111-9.
  6. Microleakage of cervical cavities restored with flowable composites. Am J Dent. 2004; 17(1):33-7.
  7. The effect of flexural load cycling on the microleakage of cervical resin composites. Oper Dent. 2001; 26(5):451-9.
  8. The effect of flowable resin composite on microleakage in class V cavities. Oper Dent. 2003; 28(1):42-6.
  9. Sturdevant's art & science of operative dentistry. 5th ed. St. Louis: Mosby, 2006. p. 529-64.
  10. The effect of dentine bonding agents on marginal leakage of composite restorations. J. Oral Rehabil. 1990; 17(6):519-27.
  11. Microleakage of tooth-colored restorations with a beveled gingival margin. Quintessence Int. 1998; 29(6):356-61.
  12. Effect of resin viscosity and enamel beveling on the clinical performance of class V composite restoration: Three year result. Oper Dent 2003;28(5):482-487.
  13. Influence of marginal bevels on microleakage around Class V cavities bonded with seven self-etching agents. Am J Dent. 2004; 17(4):257-61.
  14. Effect of cavosurface margin configuration of Class V cavity preparations on microleakage of composite resin restorations. J Contemp Dent Pract. 2008; 9(2):122-9.
  15. Depth of cure of dental resin composites: ISO 4049 depth and microhardness of types of materials and shades. Oper Dent. 2008; 33(4):408-12.
  16. Edge-strength of flowable resin-composites. J Dent. 2008; 36(1):63-8.
  17. Wear of composite resin veneering materials in a dual-axis chewing simulator. J Oral Rehabil. 1999; 26(5):372-8.
  18. Effect of load cycling and in vitro degradation on resin-dentin bonds using a self-etching primer. J Biomed Mater Res A. 2005; 72(4):399-408.
  19. Influence of design and mode of loading on the fracture strength of all-ceramic resinbonded fixed partial dentures: an in vitro study in a dual-axis chewing simulator. J Prosthet Dent. 2000; 83(5): 540-7.
  20. Clinical and laboratory evaluation of adhesive restorative systems. Am J Dent. 1994; 7(4):217-9.
  21. SEM and microleakage evaluation of the marginal integrity of two types of class V restorations with or without the use of a light-curable coating material and of polishing. J Dent. 2008; 36(11):885-91.
  22. Influence of location of the gingival margin on the microleakage and internal voids of nanocomposites. J Contemp Dent Pract. 2008; 9(7):65-72.
  23. The effect of occlusal loading on the microleakage of class V restorations. Oper Dent. 2008; 33(2):135-41.
  24. Bond strengths to superficial, intermediate and deep dentin in vitro with four dentin bonding systems. Dent Mater. 1993; 9(1):19-22.
  25. Mapping of tubule and intertubule surface areas available for bonding in Class V and Class II preparations. J Dent. 1997; 25(5):375-89.
  26. Influence of the direction of tubules on bond strength of dentin. Oper Dent. 2001; 26(1):27-35.
  27. [The preparation of enamel margin beveling in proximal cavities]. Schweiz Monatsschr Zahnmed. 1992; 102(10):1181-8.
  28. Effect of occlusal load cycling on the marginal integrity of adhesive Class V restorations. Am J Dent. 1994; 7(2):111-4.
  29. The wear of dental amalgam in an artificial mouth: a clinical correlation. Dent Mater. 1985; 1(6):238-42.
  30. Bonding to enamel and dentin: a brief history and state of the art, 1995. Quintessence Int. 1995; 26(2):95-110.
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.