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


Chemical Characterization and Degree of Conversion of a Novel Denture Base Polymer Processed by a Novel Photon-thermal Dual Polymerization Technique

Raaja Raajalakshmi, Natesan Devi, Kandasamy Balu, Veeramalai Devaki, Paramasivam Arunkumar

Keywords : Camphorquinone, Co-initiator, Copolymer, Denture base resin, Dual-cure

Citation Information : Raajalakshmi R, Devi N, Balu K, Devaki V, Arunkumar P. Chemical Characterization and Degree of Conversion of a Novel Denture Base Polymer Processed by a Novel Photon-thermal Dual Polymerization Technique. World J Dent 2022; 13 (5):513-519.

DOI: 10.5005/jp-journals-10015-2109

License: CC BY-NC 4.0

Published Online: 22-07-2022

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


Aims and objectives: The present research aimed to characterize the thermo-polymerized poly(methyl methacrylate) [TP-P(MMA)] with camphorquinone-2-(dimethylamino)ethyl methacrylate (CQ-DMAEMA) complex and to evaluate the degree of conversion (DC) of the formed novel copolymer P(MMA-co-DMAEMA). Materials and methods: The CQ was incorporated in the prepolymeric powder and the DMAEMA in the liquid monomer so that the CQ-DMAEMA ratio was 1:2. The CQ-DMAEMA complex concentration in the TP-P(MMA) was 5% (group B), 10% (group C), and 15% (group D). The TP-P(MMA) without the CQ-DMAEMA complex served as control (group A). Ten polymerized and unpolymerized specimens (n = 10 per group) were subjected to Fourier transform infrared spectroscopy (FTIR) using potassium bromide technique for assessing the copolymerization (CP) and DC. Results: New peaks ascribed to the methyl amino and tertiary amine groups were evident in all the trial groups which were absent in the control group. These peaks of the trial groups confirm the CP of the methacrylated amine with TP-P(MMA). Absence of the alkenyl C=C stretch peak in all the trial groups signifies higher DC than the control group. The TP-P(MMA) with 15% CQ-DMAEMA complex had the highest DC. Conclusion: The methacrylated amine successfully copolymerized with TP-P(MMA) which along with CQ formed a novel photon-thermal dual polymerized denture base copolymer P(MMA-co-DMAEMA) exhibiting higher DC than the conventional P(MMA). Clinical significance: The novel photon-thermal dual-polymerized denture base copolymer possessing good DC is expected to release meager or negligible amount of unreacted residual monomer and would possess palatable biocompatibility than the conventional P(MMA) without inducing denture-induced stomatitis in the edentulous geriatric population.

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