@article{article_514162, title={Fracture resistance of root-filled teeth after cavity preparation with conventional burs}, journal={European Oral Research}, volume={52}, pages={59–63}, year={2018}, author={Aydın, Uğur and Aksoy, Fatih and Tosun, Samet}, keywords={Bur, cavity preparation, Er, Cr:YSGG, Er:YAG, fracture resistance}, abstract={<p class="MsoNormal"> <span lang="en-us" xml:lang="en-us"> </span> </p> <p class="MsoNormal">Purpose <br />The aim of the present study is to compare the fracture resistance of teeth after <br />access cavity preparation with conventional rotary burs, Erbium-doped yttrium <br />aluminum garnet laser (Er:YAG) and Erbium, cromium: yttrium scandium gallium <br />garnet laser (Er,Cr:YSGG) lasers. <br />Materials and methods <br />Fifty five intact mandibular molars were divided into 3 negative groups (groups 1, 2, <br />3; n=5 for each), 3 study groups (groups 4, 5, 6; n=10 for each) and 1 positive control <br />group (intact teeth; n=10). Access cavities of groups 1, 2 and 3 were prepared with <br />conventional burs, Er:YAG laser and Er,Cr:YSGG laser respectively. After root canal <br />obturation, their coronal portions were left non-restored. Access cavities of groups 4, <br />5 and 6 were prepared by using the same equipment but their coronal portions were <br />restored with composite resinafter root canal obturation. Following thermocycling, <br />fracture strength was evaluated with a Universal Testing Machine. Mean force at which <br />each sample is fractured was recorded in Newton unit and statistically analyzed. <br />Results <br />Fracture resistance of group 7 (intact teeth) was significantly higher than all other <br />groups (p<0.001). Differences among the fracture resistance values of groups 4, 5 and 6 <br />were not significantly different but they were significantly higher than those of groups <br />1, 2 and 3 (p<0.001). No significant difference was found between Groups 1, 2 and 3. <br />Conclusion <br />Preparing access cavities with either laser or bur has no effect on the fracture <br />resistance of teeth with root canal treatment. <br /> </p>}, number={2}, publisher={Istanbul University}