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Surface properties of an indirect composite polymerized with five laboratory light polymerization systems
1Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry, Tokyo, Japan. matsumura@dent.nihon-u.ac.jp
Journal of Oral Science
|June 25, 2009
Summary
High-intensity light polymerization units effectively cure dental composites like Sinfony, ensuring good hardness and wear resistance. Proper selection of polymerization systems and modes is crucial for optimal post-curing properties.
Area of Science:
- Dental Materials Science
- Polymer Chemistry
Background:
- The properties of dental composites are significantly influenced by the light polymerization process.
- Understanding the impact of different laboratory light polymerization systems is essential for optimizing composite performance.
Purpose of the Study:
- To evaluate how various laboratory light polymerization systems affect the post-curing properties of an indirect composite (Sinfony).
- To determine the influence of different polymerization modes on Knoop hardness, wear depth, and gloss.
Main Methods:
- An indirect composite (Sinfony) was polymerized using five different light systems and nine polymerization modes.
- Knoop hardness number, wear depth after toothbrush abrasion, and surface gloss changes were measured post-polymerization.
Main Results:
- Hyper LII (120s) and Pearlcure Light (120s) yielded the highest Knoop hardness numbers.
- Six polymerization groups showed comparable or superior wear resistance to toothbrush abrasion.
- Surface gloss was significantly reduced after toothbrush dentifrice abrasion, irrespective of the initial polymerization mode.
Conclusions:
- High-intensity light polymerization units can sufficiently cure the Sinfony composite.
- The choice of polymerization system and mode impacts hardness and wear resistance.
- Further research may explore long-term clinical performance and different composite materials.
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