International Journal of Prosthodontics and Restorative Dentistry

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VOLUME 1 , ISSUE 3 ( October-December, 2011 ) > List of Articles

RESEARCH ARTICLE

A Comparative Study on the Effect of Two Different Investing Mediums on the Movement of Artificial Teeth during the Fabrication of Complete Denture: An in vitro Study

Citation Information : A Comparative Study on the Effect of Two Different Investing Mediums on the Movement of Artificial Teeth during the Fabrication of Complete Denture: An in vitro Study. Int J Prosthodont Restor Dent 2011; 1 (3):141-146.

DOI: 10.5005/jp-journals-10019-1027

Published Online: 01-12-2011

Copyright Statement:  Copyright © 2011; Jaypee Brothers Medical Publishers (P) Ltd.


Abstract

Purpose

Acrylic processing of waxed-up dentures is considered to be a crucial and technique-sensitive procedure. Even after investing a lot of time and clinical skill a definitive movement of teeth during and after processing has long been observed which lead to occlusal discrepancies and disturb the harmonious occlusal scheme achieved earlier. Shifting of the teeth can occur as a result of the investing procedures and investing materials. The objective of this study was to evaluate and compare the movement of artificial teeth in two-dimensions of space (anteroposterior and mediolateral) during processing of the waxed-up dentures using two different gypsum materials for investing.

Methods

Two groups of 15 waxed-up maxillary dentures were processed using two different investing mediums (a) dental plaster and (b) combination of dental stone core and plaster mold. The artificial teeth movement was measured in the mediolateral and the anteroposterior directions between predetermined reference points before and after processing with the aid of a traveling microscope. The findings were statistically analyzed using parametric t-tests and ANOVA F-test.

Results

Artificial teeth movement in both the anteroposterior and mediolateral direction was less with the use of investment combination of dental stone core and plaster mold when compared to the conventional method of investing with dental plaster.

Conclusion

The dental stone core method is superior in view of the fact that it produces significantly less artificial teeth movement than the conventional method. However, neither of the investing methods is successful in completely preventing artificial teeth movement.


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  1. Physical properties of denture resins: Part I. Curing shrinkage and water sorption. J Am Dent Assoc 1943;30:1845-52.
  2. Changes caused by processing complete mandibular dentures. J Prosthet Dent 1994;72:605-13.
  3. Control of increased vertical dimension of compression molded dentures. J Prosthet Dent 1961;11: 1080-85.
  4. Elevation of incisal guide pin following attachment of casts to articulator. J Prosthet Dent 1963;13:664-68.
  5. Comparison of the dimensional accuracy of injection-molded denture base materials to that of conventional pressure-pack acrylic resin. J Prosthodont 2004;13:83-89.
  6. Comparison of the occlusal vertical dimension after processing complete dentures made with lingualized balanced occlusion and conventional balanced occlusion. J Prosthet Dent 2006;96:200-04.
  7. Denture duplication technique with alternative materials. J Prosthet Dent 1997;77: 97-98.
  8. Comparison of palatal adaptation in acrylic resin denture bases using dimensional change in dentures processed in silicone and stone moulds. Eur J Prosthodont Restor Dent 2002;10:43-45.
  9. Effect of processing method on the dimensional accuracy and water sorption of acrylic resin dentures. J Prosthet Dent 1999;81: 300-04.
  10. Movement of artificial teeth in waxed trial dentures. J Prosthet Dent 1986;56:644-48.
  11. Relationship of investing medium to occlusal changes and vertical opening during construction. J Prosthet Dent 1976;36:501-08.
  12. Rigid and resilient investing materials- expected movement of teeth in the fabrication of complete dentures: An in vitro study. J Indian Prosthodont Soc 2005;5: 23-25.
  13. Dimensional stability of distances between posterior teeth in maxillary complete dentures. Braz Oral Res 2006;20:241-46.
  14. Distortion behavior of heat-activated acrylic denture-base resin in conventional and long, low-temperature processing methods. J Dent Res 1998;77:1446-53.
  15. The effect of cyclic drying on dimensional changes of acrylic resin maxillary complete dentures. Journal of Oral Rehab 2006;33:654-59.
  16. J Oral Rehab 2002;29:787-90.
  17. Effect of bench cooling on the dimensional accuracy of heat-cured acrylic denture base material. J Dent 2005;33:57-63.
  18. Complete denture prosthodontics (2nd ed), New York; McGraw-Hill Book Company Inc: page 266.
  19. Changes in the relative position of teeth in the construction of denture bases. J Dent Res 1962;41:1450-60.
  20. Dimensional and occlusal changes in fluid resin dentures. J Prosthet Dent 1978;39:605-15.
  21. The comparison of denture- base processing techniques-Part II. Dimensional changes due to processing. J Prosthet Dent 1977;39:605-15.
  22. Dimensional accuracy of two denture base processing methods. Int J Prosthodont 1989; 2:421-28.
  23. The effect of denture teeth on the dimensional accuracy acrylic resin denture bases. Int J Prosthodont 1990;3:528-37.
  24. Moire topography for measuring the dimensional accuracy of resin complete denture bases. Int J Prosthodont 1989; 2:272-79.
  25. Comparison of changes in vertical dimension between compression and injection molded complete dentures. J Prosthet Dent 1989;62:716-18.
  26. Microwave energy polymerization of poly (methyl methacrylate) denture base resin. Int J Prosthodont 1989;2:453-58.
  27. Dimensional accuracy of denture resin cured by microwave energy. J Prosthet Dent 1991;66:403-08.
  28. Comparison of the adaptation of acrylic resin cured by microwave energy and conventional water bath. Quintessence Int 1991;22:181-86.
  29. Dimensional stability of distances between teeth in complete dentures comparing microwave polymerization and conventional cycles. Braz J Oral Sci 2010;9(3):384-87.
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