Comparison of the Heat Generation of Light Curing Units
Bora Bağiş, Yildirim Bagis, Ertan Ertas, Seda Ustaomer
Citation Information :
Bağiş B, Bagis Y, Ertas E, Ustaomer S. Comparison of the Heat Generation of Light Curing Units. J Contemp Dent Pract 2008; 9 (2):65-72.
The aim of this study was to evaluate the heat generation of three different types of light curing units.
Methods and Materials
Temperature increases were recorded from a distance of 1 mm from a thermocouple to the tip of three different types of light curing units including one quartz-tungsten halogen (QTH), one plasma arc (PAC), and one light emitting diode (LED) unit. An experimental model was designed to fix the 1 mm distance between the tip of the light curing units and the thermocouple wire. Temperature changes were recorded in 10 second intervals up to 40 seconds. (10, 20, 30, and 40 seconds). Temperature measurements were repeated three times for every light curing unit after a one hour standby period. Statistical analysis of the results was performed using the analysis of variance (ANOVA) and the Bonferroni Test.
Results
The highest temperature rises (54.4±1.65°C) occurred during activation of a PAC light curing unit for every test period (p<.05). The least temperature increase (11.8±1.3°C) occurred with a LED curing unit for each tested period except for the measurement of the temperature rise using the QTH curing unit at the tenth second interval (p<.05).
Conclusion
These results indicate the choice of light activation unit and curing time is important when polymerizing light activated resin based restorations to avoid any thermal damage to the pulp.
Citation
Bagis B, Bagis Y, Ertas E, Ustaomer S. Comparison of the Heat Generation of Light Curing Units. J Contemp Dent Pract 2008 February;(9)2:065-072.
Curing of dental composites by use of InGaN light-emitting diodes. Opt Lett. 1999; 24:67-68.
Performance of two blue light-emitting-diode dental light curing units with distance and irradiation-time. Dent Mater. 2004; 20:72-79.
Candela-class high brightness InGaN/AlGaN double heterostructure blue-light-emitting diodes. Appl Phys Lett 1994;64:1687–9.
Handbook of optics. Vol. 2: Devices, measurements, and properties. New York: McGraw-Hill, 1995;121–123.
An in vivo study to compare a light and a conventional quartz halogen curing light in ortodontiv bonding. Eur J Orthod. 2004; 26:573-577.
Huck, Kahl-Nieke B. Curing lights for orthodontic bonding. Am J Orthod Dentofacial Orthop. 2002; 122:643-8.
Effects of conventional and high-intensity lightcuring on enamel shear bond strength of composite resin and resin-modified glass-ionomer. Am J Orthod Dentofacial Orthop. 2000; 119:30-5.
Characterization of resin composites polymerized with curing units. Dent Mater. 2000;16:330–336.
Cure performance of light-activated composites by differential thermal analysis (DTA). Dent Mater. 1985;1:231–234.
Pulp chamber temperature changes with visible-lightcured composites in vitro. Dent Mater. 1990;6:99–102.
Computer-controlled differential calorimetry of dental composites,. IEEE Trans Biomed Eng. 1991;131:319–325.
In vitro temperature rises produced by five polymerising light sources. Restorative Dent. 1988;4:33–35.
The use of differential scanning calorimetry for the evaluation of dental materials. I. Cements, cavity lining materials and anterior restorative materials. J Oral Rehabil. 1980;7:103–110.
Effect of Light-tip Distance on the Shear Bond Strengths of Composite Resin. Angle Orthodont 2005;75:386–391.
Comparison of quartz-tungsten-halogen, light-emitting diode, and curing lights. J Adhes Dent. 2003; 5(3):193-207.
Effect of different light sources and guides on shear bond strength of brackets bonded with 2 adhesive systems. Am J Orthod Dentofacial Orthop. 2005; 128:99-102.
Thermal emission by different light-curing units. Oper Dent. 2003;28:260–266.
Jandt Polymerization and light-induced heat of dental composites cured with LED and halogen technology. Biomater. 2003; 24:1809-1820.
Temperature rise in the pulp chamber induced by a conventional halogen light-curing source and a lamp. Am J Dent. 2004;17:203-8.