Can phenyl-propanedione influence Knoop hardness, rate of polymerization and bond strength of resin composite restorations?
In: Journal of dentistry, Jg. 39 (2011), Heft 6, S. 438-447
academicJournal
- print, 23 ref
Zugriff:
Objectives: The aim of this study was to evaluate the degree of conversion (DC), rate of polymerization (Rpmax), Knoop hardness (KHN) and bond strength between tooth/restoration of composite resins containing different photo-initiators photo-activated by different light-curing units (LCUs). Materials and methods: A mixture of BisGMA, UDMA, BisEMA and TEGDMA was prepared along with the following photo-initiators: camphorquinone (CQ), phenyl-propanedione (PPD) or the association (CQ/PPD) and 65 wt% of silanated filler particles. The LCUs included a halogen lamp XL 2500 and two LEDs: UltraBlueIS and UltraLume5. The conversion profiles during photo-polymerization were investigated using middle-infrared spectroscopy (mid-IR). Bond strength was evaluated using push-out test in ninety teeth with prepared cavities. Before the push-out test, Knoop hardness (KH) was verified in the top and at the base of the restorations. Results: PPD obtained lower Rpmax values, regardless of the LCU used. It also provided a greater bond strength than CQ when the LEDs LCUs were used. The degree of conversion after 40 s of irradiation was the same for all composite resins, except PPD photo-activated for XL 2500, which showed lower DC values than CQ and CQ/PPD. In the top and at the base of the restorations, PPD showed the lowest KH values when photo-activated with XL 2500. XL 2500 produced higher KH values than UltraBlueIS when used with CQ or CQ/PPD photo-initiators. Conclusion: Because it increased the bond strength without compromising the properties of composite resins when photo-activated by an LED, PPD can be used as an alternative photo-initiator.
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Can phenyl-propanedione influence Knoop hardness, rate of polymerization and bond strength of resin composite restorations?
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Autor/in / Beteiligte Person: | CUNHA BRANDT, William ; DE OLIVEIRA TOMASELLI, Lucas ; CORRER-SOBRINHO, Lourenço ; COELHO SINHORETI, Mário Alexandre |
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Zeitschrift: | Journal of dentistry, Jg. 39 (2011), Heft 6, S. 438-447 |
Veröffentlichung: | Kidlington: Elsevier, 2011 |
Medientyp: | academicJournal |
Umfang: | print, 23 ref |
ISSN: | 0300-5712 (print) |
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