基本解釋[醫(yī)藥科學]被動逐步后退法英漢例句雙語例句Methods Forty-five mesiobuccal root canals in fleshly extracted nu a an molar teeth were instrumented by the step-back technique , the step-down technique or the passive step-back technique.目的對逐步后退法、逐步深入法、被動逐步后退法（超聲波與手用器械聯(lián)合應用）三種不同方法預備后牙細彎根管的根管清理能力及操作時間進行比較研究。passive step-back technique更多例句專業(yè)釋義醫(yī)藥科學被動逐步后退法