Background: Reprocessing the permanent denture base after try-in is a common procedure in the complete denture fabrication. It is speculated that subjecting polymerized Poly-methyl methacrylate resin again to heat, during reprocessing can induce dimensional changes and a significant loss of intimate fit in the denture base to the tissues, can ultimately reduce the retention and stability of the complete denture.
Aim and Objectives: The aim of the study is to evaluate the effect of reprocessing on the accuracy of fit of permanent poly-methyl methacrylate den-ture bases.
Material and Methods: A resin edentulous maxillary model was duplicated and a total of twenty casts were poured with type III gypsum product. Group I: Permanent denture bases fabricated with heat polymerized Polymethyl-methacrylate resin. Group II: Group I permanent denture bases with wax rims reprocessed with heat polymerized Po-lymethylmethacrylate resin. Both the group were evaluated for fit using a travelling microscope.
Results: Statistical analysis revealed that at each measurement period the mean posterior palatal border openings were not significantly different for processed and reprocessed denture bases. (p > 0.05).
Discussion: Reprocessing permanent denture base under controlled laboratory conditions without significant dimensional change, will encourage the clinicians to use permanent record base during jaw relations and try-in. Conclusion: Maxillary permanent complete denture bases were not found to distort significantly as a result of first and second curing cycle. The central part of the posterior palatal border of the denture showed the greatest discrepancy, which was as less as 0.11 to 0.13mm. Reprocessing the perma-nent complete denture base in controlled laboratory conditions will not affect the fit and adaptation.
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