目的　研究 RPA卡环在游离端义齿应用中支持组织的应力分布状况。方法　用三维有限元的方法对 RPA卡环和传统三臂卡环修复下颌末端游离缺失时 ,在垂直加载情况下 ,对近基牙支持组织的应力和位移进行分析。结果　 RPA卡环在 3个方向上的最大应力值和位移值均明显小于三臂卡环 ,其基牙受力趋向于轴向力。结论　 RPA卡环有利于基牙的健康 ,为临床应用提供了生物力学依据 Objective To study the stress distribution of RPA retaining ring in the application of free end denture. Methods Three-dimensional finite element method was used to analyze the stress and displacement of the supporting tissue of the proximal abutment under the vertical loading condition when the RPA retaining ring and the traditional three-armed retaining ring were used to repair the mandibular distal free loss. Results The maximum stress and displacement of RPA ring in three directions were significantly less than those of the three-arm ring, and the abutment force tended to axial force. Conclusion RPA ring is beneficial to the health of abutments and provides a biomechanical basis for clinical application