Degree of conversion, depth of cure, and color stability of experimental dental composite formulated with camphorquinone and phenanthrenequinone photoinitiators.

Autor: Albuquerque PP; Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo-USP, São Paulo, Brazil., Bertolo ML, Cavalcante LM, Pfeifer C, Schneider LF
Jazyk: angličtina
Zdroj: Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.] [J Esthet Restor Dent] 2015 Mar-Apr; Vol. 27 Suppl 1, pp. S49-57. Date of Electronic Publication: 2015 Apr 17.
DOI: 10.1111/jerd.12131
Abstrakt: Purpose: This study evaluated the applicability of 9,10-phenanthrenequinone (PQ) in experimental dental composites.
Materials: Camphorquinone (CQ), PQ, ethyl 4-N,N-dimethylaminobenzoate (EDMAB) and diphenyliodonium salt (DPI) were employed. A mixture of 2,2-bis(4-[2-hydroxy-3-methacryloxypropoxy]phenyl)-propane/triethylene glycol dimethacrylate (60:40%) and silanated glass filler at 60% were used. A two-peak-based light-emitting diode (LED) was used.
Methods: The photoinitiator absorption and the light emission spectra were determined by a Ultraviolet-visible spectroscopy and a spectroradiometer, respectively. Relative photon absorption (RPabs) was calculated. Fourier-transformed infrared spectroscopy analysis was used to determine the degree of conversion (DC). The optical properties were determined with a spectrophotometer. Depth of cure was assessed from adapted International Organization for Standardization (ISO) 4049. Results were analyzed with descriptive analysis, analysis of variance, and Tukey's test (α = 5%).
Results: PQ showed higher RPabs than CQ. Regarding the DC, CQ + EDMAB (control), CQ + EDMAB + DPI, PQ + DPI, and PQ + EDMAB + DPI produced statistically similar results. Groups formulated with CQ presented higher depth of cure. Only the group formulated with CQ + EDMAB presented satisfactory color stability (ΔE < 3.3).
Conclusion: PQ presented higher RPabs than CQ and it was able to produce DC similar to CQ + EDMAB, when used with DPI. However, groups formulated with PQ produced lower depth of cure, greater yellowing, and less color stability than the traditional combination CQ and amine.
Clinical Significance: Although research with novel photoinitiator systems should be encouraged, the traditional camphorquinone and amine pair remains as a reliable combination for the formulation of dental composites.
(© 2015 Wiley Periodicals, Inc.)
Databáze: MEDLINE
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