Heat generation caused by ablation of restorative materials with an ultrashort pulse laser (USPL) system
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Andreas Braun & Richard Johannes Wehry & Olivier Brede & Claudia Dehn & Matthias Frentzen & Florian Schelle
- چاپ و سال / کشور: 2010
Description
Heat generation during the removal of dental restorative materials may lead to a temperature increase and cause painful sensations or damage dental tissues. The aim of this study was to assess heat generation in dental restoration materials following laser ablation using an ultrashort pulse laser (USPL) system. A total of 225 specimens of phosphate cement (PC), ceramic (CE), and composite (C) were used, evaluating a thickness of 1 to 5 mm each. Ablation was performed with an Nd:YVO4 laser at 1,064 nm, a pulse length of 8 ps, and a repetition rate of 500 kHz with a power of 6 W. Employing a scanner system, rectangular cavities of 1.5-mm edge length were generated. A temperature sensor was placed at the back of the specimens to record the temperature during the ablation process. All measurements were made employing a heatconductive paste without any additional cooling or spray. Heat generation during laser ablation depended on the thickness of the restoration material (p<0.05) with the highest values in the composite group (p<0.05), showing an increase of up to 17 K. A time delay for temperature increase during the ablation process depending on the material thickness was observed in the PC and C group (p< 0.05) with highest values for cement (p<0.05). Employing the USPL system for removal of restorative materials, heat generation has to be considered. Especially during laser ablation next to pulpal tissues, painful sensations might occur.
Lasers Med Sci DOI 10.1007/s10103-010-0875-9 Received: 4 August 2010 / Accepted: 23 December 2010
