Abstract | OBJECTIVES: A potential problem with high-intensity lights might be failure of polymer chains to grow and cross-link in a desired fashion, thereby affecting the structure and properties of the polymers formed. The purpose of this study was to evaluate mechanical properties of resin composites polymerized using four different light-curing units. METHODS: A conventional quartz- tungsten- halogen (QTH) light, a soft-start light, an argon-ion laser, and a plasma- arc curing light were used to polymerize disk-shaped (9.0mm diameter x 1.0 mm high) and cylinder-shaped (4mm diameter x 8 mm high) specimens of a universal hybrid and a flowable hybrid composite. Biaxial flexure strength, fracture toughness, hardness, compressive strength, and diametral tensile strength were determined for each composite. RESULTS: The use of the plasma- arc curing light, a high-intensity light, resulted in significantly lower hardness for the universal hybrid composite compared with the hardness obtained using the conventional QTH and the soft-start units. Hardness was the only mechanical property that was adversely affected by the use of a high-intensity light. SIGNIFICANCE: High-intensity lights might affect some resin composite mechanical properties, but this effect cannot be generalized to all resin composites and all properties.
|
Authors | Annie J St-Georges, Edward J Swift, Jeffrey Y Thompson, Harald O Heymann |
Journal | Dental materials : official publication of the Academy of Dental Materials
(Dent Mater)
Vol. 19
Issue 5
Pg. 406-13
(Jul 2003)
ISSN: 0109-5641 [Print] England |
PMID | 12742436
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
|
Chemical References |
- Composite Resins
- Halogens
- Resin Cements
- Revolution (composite resin)
- Herculite XR
- Xenon
|
Topics |
- Composite Resins
(radiation effects)
- Compressive Strength
(radiation effects)
- Dental Restoration, Permanent
- Dental Stress Analysis
- Halogens
- Hardness
(radiation effects)
- Lasers
- Light
- Materials Testing
- Pliability
(radiation effects)
- Resin Cements
(radiation effects)
- Tensile Strength
(radiation effects)
- Xenon
|