Eric Rompen

Temperature rise during photo-activated disinfection of root canals

The aim of this study was to determine whether it is safe to use photo-activated disinfection (PAD) during root canal treatment without heating the periodontal tissues. Root canals of 30 freshly extracted single-rooted teeth were prepared using ProFiles up to size ISOxa040 and then filled with photo-sensitiser: tolonium blue (1.2xa0mg/l). The 635xa0nm diode laser was used with the manufacturer’s endo-tip. Samples were irradiated for 150xa0s (output power 100xa0mW, approximate energy density 106.16xa0J/cm2). Temperatures were recorded at working length on the external root surface. After 150xa0s of PAD irradiation, the average temperature rise was 0.16u2009±u20090.08°C. All values were lower than the 7°C safety level for periodontal injury. It was concluded that, regarding the temperature increase, the use of PAD in root canals could be considered harmless for periodontal tissues.

Comparison of microleakages of photo-cured composites using three different light sources: halogen lamp, LED and argon laser: an in vitro study

In this study, we compared the microleakage of composite fillings cured with halogen bulb, LED and argon ion laser (488xa0nm). Twenty-four extracted human molars were divided randomly in three groups. Six cavities were prepared on the coronal part of each tooth. Standard cavities (1.7u2009×u20092xa0mm) were prepared. Cavities were acid etched, sealed with Scotch Bond 1 and filled by a hybrid composite. Cavities were exposed to one light source, thermocycled and immersed in a 2% methylene blue dye solution. Dye penetration in the leakage of cavities was recorded using a digital optical microscope. Mean values of percentage of dye penetrations in microleakages of cavities were 49.303u2009±u20095.178% for cavities cured with LED, 44.486u2009±u20096.075% with halogen bulb and 36.647u2009±u20095.936% for those cured by argon laser. Statistically significant difference exists between cavities cured by halogen vs LED (Pu2009<u20090.01), halogen vs laser (Pu2009<u20090.001) and LED vs laser (Pu2009<u20090.001). The lowest microleakage was observed in the cavities and composites cured with argon ion laser.