Burs
abbr. Bursar (大学的)会计员,出纳员,大学生津贴
He picked off the burs that had stuck to his overcoat.
他摘下粘在外衣上的刺果.
Methods: The root canalroot canal orifice burs and helical drilling bits were prepared in advance.
方法: 采用根管口台阶状车针与螺旋型根管钻组合起来扩大根管.