European Journal of Prosthodontics and Restorative Dentistry
- Cover Date:
- March 2006
- Print ISSN:
- 0965-7452
- Vol:
- 14
- Issue:
- 1
Surface Microhardness of a Resin Composite: a Comparison of a Tungsten Halogen and a LED Light Curing Unit, in vitro
Abstract - A comparison has been made between published surface microhardness numbers (VHN) of a commercial resin composite for different exposure times to a quartz tungsten halogen (QTH) and light-emitting diode (LED) light-curing unit (LCU). Both LCUs produced comparable hardness at both top and bottom surfaces, respectively, and similar bottom/top hardness ratios, for a specimen thickness of 1.5 mm, given sufï¬cient exposure time (40 s) and an elapsed time of 24 h before measurement (for hardness numbers). However, some data are signiï¬cantly different. There is no advantage in either LCU regarding optimal hardness and hardness ratios given an appropriate protocol. Immediate ï¬nishing (1 h) was more appropriate to the use of the LED LCU (with adequate exposure time). The effect of elapsed time after exposure on microhardness was more pronounced with the QTH LCU.
KEY WORDS: Resin Composite; Surface Microhardness; Light-Activation; Tungsten Halogen; Light Emitting Diode; Exposure Times
- Article Price
- £15.00
- Institution Article Price
- £
- Page Start
- 7
- Page End
- 12
- Authors
- Noel J. Ray, Christopher D. Lynch, Francis M. Burke, Ailish Hannigan
Articles from this issue
- Title
- Pg. Start
- Pg. End
- Effect of Five Staining Solutions on the Colour Stability of Two Acrylics and Three Composite Resins Based Provisional Restorations
- 2
- 6
- Surface Microhardness of a Resin Composite: a Comparison of a Tungsten Halogen and a LED Light Curing Unit, in vitro
- 7
- 12
- The effect of cooking method upon the titratable acidity of a popular vegetarian dish – Scope for reducing its erosive potential?
- 28
- 31