Influence of dietary simulating solvents on the viscoelasticity of temporary soft lining materials
N J Jepson1, J T McGill, J F McCabe
1The Dental School, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom. n.j.a.jepson@ncl.ac.uk
Statement Of Problem:
Clinical changes in the viscoelasticity of temporary soft lining materials are characterized by a more rapid and increased reduction in compliance than is seen after in vitro immersion. A possible explanation for these differences is a solvent effect, acting clinically to encourage the loss of ethanol and plasticizer. Dietary solvents have been suggested as likely agents.
Purpose:
This study examined the effect of immersion in dietary simulating solvents on the viscoelasticity of temporary soft lining materials, with a view to formulating more clinically relevant immersion regimes used in the evaluation of these materials.
Material And Methods:
Four temporary soft lining materials were immersed in distilled water and solutions chosen to simulate dietary solvents. Changes in viscoelasticity over time were recorded with a penetrometer, modified to record creep strain and strain during recovery.
Results:
All immersion solutions caused a significant reduction in compliance values of each material over time (P <.05). However, only heptane and corn oil immersants produced the rapid and increased reduction in compliance that is evident clinically. Changes in elastic recovery were less pronounced.
Conclusion:
Results of this study offer support to a dietary source of solvent acting to effect clinical changes in the viscoelasticity of temporary soft lining materials.
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