• Journal of Technologic Dentistry
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• v.35 no.3
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• pp.209-218
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• 2013

Purpose: The purpose of this study was to know the availability of two photosensitizers, PD, DA, as a photosensitizer instead of CQ in UDMA dental composite resin. We want to know photopolymerization effect of UDMA unfilled resin and surface hardness of composite resin containing PD and DA were compared with those of CQ, most widely used photosensitizer for dental composite resins. Methods: The photopolymerization effect of UDMA studied by FT-IR spectroscopy increased with irradiation time and the amount of photosensitizer. Knoop hardness of experimental composite resins prepared by the addition of the photosensitizer content and irradiation time. Results: The relative photopolymerization effect of UDMA increased in the order of PD > CQ > DA. The composite resin of UDMA containing DA or PD, which shows better Knoop hardness than that containing CQ. Conclusion: PD and DA show as effective photosensizers, suitable for UDMA dental composite resin compare with a higher efficiency than CQ.

• Journal of Technologic Dentistry
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• v.33 no.4
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• pp.291-297
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• 2011

Purpose: The purpose of this study was to know the availability of three photosensitizers, CQ, PD, DA, as a photosensitizer of dental resin composite. We want to know abortion band around visible light region for the using potential possibility as a photosensitizer for visible light cured dental composite resin. And I studied to know the relative photodecomposition ratio of three photosensitizers with or without photoinitiator, DAEM. Methods: The photodecomposition of three photosensitizers were studied by UV absorption spectroscopy in ethanol and determined by same instrument with irradiation time for relative photodecomposition. In order to study the effect of amine on photodecomposition was added the DAEM in the photosensitizer solution and the relative rate was measured by the same procedure with aove mentioned. Results: The all of three photosensitizers are absorbed around visible light region. The relative rate of decrease in absorbance incereased in the order: CQ < BD < PD. The effect of DAEM on the photodecomposition of the photosensitizers was appeared different results without DAEM. The photodecomposition rate of PD and DA decreased somewhat with the addition of amine, while that of CQ increased. The rtealtive photodecomposition rate increased in the oprder: BD ${\leq}$ CQ < PD with the addition of amine, but the differnce was not significant. Conclusion: PD and DA like CQ gives to the possibility of use as a photosensitizer for visible light cured dental composite resin by absorption around visible light region and photodecomposition in the maximum absorption wavelength. And it is showed that PD and DA are not effective decomposed with amine initiator, DAEM but CQ decomposed with DAEM effectively. This result may be due to a different mechanism operating for the decomposition of photosensitizers in the presence of amine.