World Journal of Dentistry

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VOLUME 13 , ISSUE 5 ( September-October, 2022 ) > List of Articles


Effect of Recycled Denture Base Polymeric Powder Incorporation on the Surface Properties of Heat-cured PMMA Denture Base Acrylic Resin: An In Vitro Study

Divya Krishnamoorthi, Syed A Ali, Gunaseelaraj Rajkumar, Somasundaram Santhakumari, Soundararaj Ashna

Keywords : Acrylic resins, Hardness test, Recycling, Reuse

Citation Information : Krishnamoorthi D, Ali SA, Rajkumar G, Santhakumari S, Ashna S. Effect of Recycled Denture Base Polymeric Powder Incorporation on the Surface Properties of Heat-cured PMMA Denture Base Acrylic Resin: An In Vitro Study. World J Dent 2022; 13 (5):527-533.

DOI: 10.5005/jp-journals-10015-2077

License: CC BY-NC 4.0

Published Online: 22-07-2022

Copyright Statement:  Copyright © 2022; The Author(s).


Aim: The present in vitro research aimed to assess the polishability (P), translucency (T), surface hardness (SH), and surface roughness (SR) of heat-cured PMMA-based denture base resin processed after modification with recycled denture base resin (r-PMMA) at 10, 20, 30, 40, and 50% (w/w) to commercially available resin (R10, R20, R30, R40, and R50) (w/w). Materials and methods: In total, 90 rectangular specimens (n = 15) were fabricated to test P and T and were analyzed through visual inspection accordingly to ISO standardization. 90 disk-shaped specimens (n = 15) were fabricated to test SR and SH. The mean arithmetic roughness (Ra) was recorded using a surface profilometer to assess the SR. Vicker's microhardness testing was done to obtain Vickers hardness number (VHN). Data were tabulated and compared using ANOVA (α = 0.05). Further post hoc Bonferroni tests were performed on each pair of groups. Results: All the specimens tested for P and T comply with the ISO 1567. The Ra of the control group- SR R0 was found to be 0.10 µm. The modification resulted in an increase in SR and was found to be ranging from 0.11 µm (SR R10) to 0.16 µm (SR R50). The VHN recorded for the control group (SH R0) was 20.35 kg/mm2. The experimental groups demonstrated a decrease in VHN, from 16.67 kg/mm2 (SH R10) to 13.85 kg/mm2 (SH R50). Conclusion: The polymeric modification does not affect the P and T of the cured specimens. The modification resulted in an increase of SR proportional to the w/w of r-PMMA added. The experimental groups demonstrated a decrease in VHN as a function of an increase in the addition of r-PMMA w/w. Clinical significance: The ability to reuse denture base resin would significantly reduce the nonbiodegradable type of biomedical waste that is produced and sent out of the dental institutes and practice.

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