Aim : The aim of the study is to compare the effectiveness of using Er: YAG and Er,Cr:YSGG lasers in debonding of two different types of ceramic brackets and its effect on enamel surface.
Materials and Methods : 72 polycrystalline and 72 monocrystalline ceramic brackets were bonded to 144 freshly extracted human premolars. The teeth were randomly divided into three groups of 48 and each group was further subdivided into 2 subgroups of 24. Group 1 was the control group where mechanical debonding of the two types of ceramic brackets was performed. Group 2 and 3 , Er:YAG and Er,Cr:YSGG lasers were used in the debonding process of the two types of the ceramic brackets , during the laser debonding process , a K-type thermocouple device was used to assess intrapulpal temperature change during laser irradiation. The adhesive remnant index was recorded for all 3 groups. Time needed for debonding was also recorded. Data were analyzed using SPSS version 20, Graph Pad Prism and Microsoft Excel.
Results: Laser debonding ceramic brackets is effective and more convenient than conventional methods. Monocrystalline brackets debond faster with Er:YAG laser than Er,Cr:YSGG laser, but polycrystalline brackets have a highly significant difference in ARI, with Er,Cr:YSGG laser having lower ARI values than the other two methods. The two laser groups' temperature rise was below the biological limit, making ceramic bracket debonding safe. No group had enamel damage.
Conclusions: Er:YAG laser debond monocrystalline brackets faster than polycrystalline brackets. Lasers are more effective in debonding ceramic brackets.