Compressive strength of esthetic restorative materials polymerized with quartz-tungsten-halogen light and blue LED

Abstract

This study compared the compressive strength of a composite resin and compomer photoactivated with a conventional quartz-tungsten halogen-light (XL 3000, 3M/SPE) and a blue light-emitting diode (LED) (SmartLite PS; Dentsply/De Trey). Forty disc-shaped specimens were prepared using a split polytetrafluoroethylene matrix (4.0 mm diameter x 8.0 mm hight) in which the materials were inserted incrementally. The curing time of each increment was of 40 s with the QTH and 10 s with the LED. The specimens were randomly assigned to 4 groups (n=10), according to the light source and the restorative material. After storage in distilled water at 37 degrees C +/- 2 degrees C for 24 h, the specimens was tested in compressive strength in a universal testing machine with load cell of 500 kgf running at a crosshead speed of 0.5 mm/min. Data (in MPa) were analyzed statistically by ANOVA and Student-Newman-Keuls test (p<0.05). For the composite resin, light curing with the QTH source did not produce statistically significant difference (p>0.05) in the compressive strength when compared to light curing with the LED source. However, light curing of the compomer with the QTH source resulted in significantly higher compressive strength than the use of the LED unit (p>0.05). The composite resin presented significantly higher (p>0.05) compressive strength than the compomer, regardless of the light source. In conclusion, the compressive strength of the tested materials photoactivated with a QTH and a LED light source was influenced by the energy density employed and the chemical composition of the esthetic restorative materials.

Fracture process characterization of fiber-reinforced dental composites evaluated by optical coherence tomography, SEM and optical microscopy

“…A compressive study was performed by Dias and Silva (18), the authors found that the composite resin light-cured with either a halogen lamp or a LED source was similar. However, it may be speculated that the high radiation emitted by the LED in short exposure duration, accelerates the curing reaction, reducing the polymer flowability, increasing the modulus of elasticity and shortening the pre-gel phase, which could interfere with the results of resistance to compression.…”

Effects of Curing Time on Compressive Strength of Hybrid Ionomer (In Vitro Study)

“…Silva CM et al 14 concluded that the compressive strength of the composite resin light-cured with either a halogen lamp or a LED source was similar.…”

Composite adhesive restorative materials for dental applications

“…Contrary to the paper by Yüzügüllü et al (2008), outcomes indicate that the compressive strengths of resin-composite fi lling materials are less than dental amalgam, showing the lowest physical properties in the microfi lled hybrid materials, whereas all other groups (hybrid, nano-hybrid, packable and ormocer) were not signifi cantly different. They concluded that most categories of resin composite, except the microfi lled materials, can be regarded as being suitable for loading in posterior restorations, but care is needed for large restorations and for those patients that show © Woodhead Publishing Limited, 2013 Bryant (1979); Combe et al (1999); el-Kalla and Garcia-Godoy (1999); Xie et al (2000); Peez and Frank (2006); Craig (1997), Yüzügüllü et al (2008); Ilie and Hickel (2009); Silva and Dias (2009). occlusal functional habits such as bruxism. It is known that microfi lled materials tend to chip more easily than 'conventional' composite materials (Lambrechts et al, 1982) and therefore should not be used in load bearing restorations.…”