International Journal of Prosthodontics and Restorative Dentistry

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VOLUME 4 , ISSUE 3 ( July-September, 2014 ) > List of Articles

RESEARCH ARTICLE

Comparative Evaluation of Heat-Polymerized and Auto-Polymerized Soft Liners with Regard to Transverse Bond Strength, Peel Bond Strength and Water Sorption: An in vitro Study

Prasanna Laxmi Krishnappan, Ragavendra Jaiesh, TN Swaminathan

Citation Information : Krishnappan PL, Jaiesh R, Swaminathan T. Comparative Evaluation of Heat-Polymerized and Auto-Polymerized Soft Liners with Regard to Transverse Bond Strength, Peel Bond Strength and Water Sorption: An in vitro Study. Int J Prosthodont Restor Dent 2014; 4 (3):61-67.

DOI: 10.5005/jp-journals-10019-1109

Published Online: 01-09-2014

Copyright Statement:  Copyright © 2014; The Author(s).


Abstract

Purpose

This is an in vitro study for comparative evaluation of transverse bond strength, peel bond strength and water sorption properties between heat polymerized and auto-polymerized resins.

Materials and methods

Two denture soft liners (Molloplast-B, Coe-Soft) were investigated. A total number of 60 specimens were used. Twenty specimens were used for evaluation of each physical property of soft liner. For transverse bond strength, ten specimens (64 ⨯ 2.5 ⨯ 10 mm) of each liner were made by processing the denture liners with heat cure polymethyl methacrylate (Meliodent). All specimens for transverse bond strength were conducted on samples immersed in distilled water at 37°C for 50 hours by using three-point transverse flexural tests in a Lloyd's Universal Testing Machine and transverse bond strength was calculated based on the maximum load, span length, breadth and thickness. Another set of ten specimens of (75 ⨯ 25 ⨯ 3 mm) of each denture liner were bonded over 25 mm of heat cure PMMA and separated over the remaining 50 mm of acrylic plate to estimate the peel bond strength. The peel bond strength were conducted on specimens which were dried at room temperature for 48 hours and tested at 21 1 ± C in a Lloyd's testing machine that was linked to an IBM Compatible Computer. The specimens were deformed with a cross head speed of 5 mm/minute according to ASTMD-903 and peel bond strength was calculated when peel angle was 180°. For water sorption tests, ten disc shaped samples of each liner of 50 mm in diameter and 0.5 mm in thickness were fabricated. After polymerization of the liners, the samples were then stored in distilled water at 37°C for 7 days. After one week, excess moisture was removed and each sample was weighed using electronic weighing machine.

Results

The transverse bond strength of Molloplast-B and Coe-Soft were almost similar and did not show any significant difference in their values. But, there is a significant decrease in the peel bond strength and water sorption property of Molloplast-B and Coe-Soft.

Conclusion

The reason for transverse bond strength results being similar for both the liners is because they were polymerized chemically with the denture base resins and this chemical affinity could have made its bond strength almost equal. Since, there is a decrease in the peel bond strength of Molloplast-B, the chances of stripping of the liner at the flanges of the denture is minimal. The decrease in water sorption of Molloplast-B can be expected to retain the bond with the denture and sustain the resilience property of the material for a longer time.

How to cite this article

Krishnappan PL, Jaiesh R, Swa- minathan TN. Comparative Evaluation of Heat-Polymerized and Auto-Polymerized Soft Liners with Regard to Transverse Bond Strength, Peel Bond Strength and Water Sorption: An in vitro Study. Int J Prosthodont Restor Dent 2014;4(3):61-67.


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  1. Resilient soft liners and tissue conditioners. Br Dent J 1988;164(11):357-360.
  2. Variations in the elastic modulus of a soft lining material. Br Dent J 1980;149(3):79-82.
  3. Resiliency of surface sealed temporary soft denture liners. J Prosthet Dent 1997; 77(4):370-374.
  4. The science of dental materials. 10th ed. Co. Philadelphia; 1996. p. 246-248.
  5. A polyvinyl siloxane denture soft lining material. J Dent 1998;26(5-6):521-526.
  6. Characterisation of the physical properties of resilient denture liners. Int J Prosthodont 1994; 7(2):120-128.
  7. Variables affecting silicone Polymethyl methacrylate interfacial bond strengths. J Prosthodont 1993;2(1):13-18.
  8. Dynamic viscoelastic properties of processed soft denture liners. Part-I Initial properties. J Prosthet Dent 1995;73(5):471-475.
  9. Dynamic viscoelastic properties of processed soft denture liners. Part- II. Effect of aging. J Prosthet Dent 1995;74(2):299-304.
  10. Water sorption, solubility and bond strength of two autopolymerizing acrylic resins and one heat polymerizing acrylic resin. J Prosthet Dent 1998;80(4):434-438.
  11. Effect of heat treatment on the linear dimensional change of hard chair side reline resin. J Prosthet Dent 2002;88(6):611-615.
  12. Unrestricted linear dimensional changes of two hard chair side reline resins and heat cured acrylic resin. J Prosthet Dent 1996;76(4):414-417.
  13. Transverse bond strength of repaired acrylic resin strips and temperature rise of dentures relined with VLC resin. J Prosthet Dent 1995;74(4):392-396.
  14. Bond strength of permanent soft denture liners bonded to the denture base. J Prosthet Dent 1995 1995;74(6):595-600.
  15. Effect of test method on the bond strength of a silicone resilient denture lining material. J Prosthet Dent 1996;76(5):535-540.
  16. Comparison of tensile and peel bond strength of resilient liners. J Prosthet Dent 1994;71(5):525-530.
  17. Some variables influencing the bond strength between PMMA and a silicone denture lining material. Int J Prosthodont 2002; 15(1):55-58.
  18. The effect of thermocycling on peel strength of six soft lining materials. J Oral Rehabil 2002;29(6):583-587.
  19. Shear Bond strength of denture reline polymers to denture base polymers. Int J Prosthodont 2001;14(3):271-275.
  20. Assessment of shear bond strength between three denture reline materials and adventure base acrylic resin. Int J Prosthodont 2001;14(6):531-535.
  21. Comparative study of water sorption, solubility and tensile bond strength of two soft lining materials. J Prosthet Dent 2000;83(3):356-365.
  22. Tissue conditioners III: Water immersion characteristics. J Dent Re 1971;50(6):144-147.
  23. Water absorption and water solubility of soft lining for acrylic dentures. J Dent Res 1983;62(60):764-768.
  24. Sorption and solubility of 12 soft denture liners. J Prosthet Dent 1994;72(4):393-397.
  25. Soft lining materials, their absorption and solubility in artificial saliva. BR Dent JK 1988;165(10): 91-94.
  26. Winter-Water sorption of RTV Silicone soft denture lining material. J Dent 1996;24(1-2):105-108.
  27. In vitro hardness, water sorption and resin solubility of laboratory processed and auto polymerized long term resilient denture liners over one year storage. J Prosthet Dent 2002;88(2):139-144.
  28. Influence of lining design of three processed soft denture liners on cushioning effect. J Oral Rehabil 1999;26(12): 962-968.
  29. The influence of immersion solutions on the visco elasticity of temporary soft lining mater. Dent Mater 1996;12(1):19-24.
  30. Composition and properties of soft lining materials for acrylic dentures. J Dent 1981;9(3):297-300.
  31. Restorative dentalmaterials. 11th ed; 2002. p. 668-670.
  32. Kawamura M. Mccabe. Dynamic viscoelasticity of soft liners and masticatory function. J Dent Res 2002;81(2):123-128.
  33. Fletcher, Ritchie. Nature of interface between PMMA denture base materials and soft lining materials. Presented at the annual conference for the study of prosthetic dentistry in April 1981. J Dent 1981;9(4):336-346.
  34. Characterisation of the rupture properties of denture soft lining materials. J Dent Res 1980;59(3):614-619.
  35. Dental laboratory procedures. Complete Dentures. 2nd ed. 1980;1:432-445.
  36. Resilient lining materials for dentures. Aust Prosthodont J 1993;(7):45-47.
  37. Comparison of the physical properties of 11 soft denture liners. J Prosthet Dent 1992; 67(5):707-712.
  38. The clinical serviceability of two permanent denture soft linings. Br Dent J 1994;177(1):11-16.
  39. Consistency and softness of soft liners. J Prosthet Dent 1996;75(1):412-415.
  40. A 6 years retrospective study of Molloplast-B lined dentures. Part II linear serviceability. J Prosthet Dent 1983;50(4):459-462.
  41. A clinical evaluation of Silastic 390 as a lining material for dentures. J Prosthet Dent 1996;16(4):650-660.
  42. Comparison of tensile and peel bond strength of resilienet liners. J Prosthet Dent 1994;71(5):525-530.
  43. Water sorption by denture acrylic resin and consequent changes in vertical dimension. J Prosthet Dent 1987;58(6):689-693.
  44. Resilient materials for denture prostheses. J Prosthet Dent 1966;16(3):438-444.
  45. Resilient liners for dentures. J Prosthet Dent 1960;10(4):664-668.
  46. Effect of storage duration on the hardness and tensile bond strength of silicone and acrylic resin based resilient denture liners to a processed denture base acrylic resin. J Prosthet Dent 2008 Feb;99(2):153-159.
  47. Sorption, solubility, bond strength and hardness of denture soft lining material. Int J Molecul Sci 2012 Dec 27;14(1):563-574.
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