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目的:探讨预烧结工艺及粉体粒度对口腔再生氧化锆性能的影响。方法:将口腔再生氧化锆粉体筛分为大颗粒（粉体粒度>50 μm且≤125 μm）及小颗粒（粉体粒度≤50 μm）两种，并分别压制成试样。将再生氧化锆粉坯依据预烧结升温速率分为A、B、C组，设置预烧结升温速率分别为2、5、8 ℃/min。以商用氧化锆预烧结体为对照，检测预烧结体的相对密度、显气孔率及切削面边缘缺口宽度。按厂家终烧结参数对各组氧化锆预烧结体进行终烧结，比较终烧结体的相对密度、显气孔率、线性收缩率及弯曲强度。通过扫描电镜观察终烧结体断裂面形貌，并用X射线衍射分析各组物相组成。结果:相同粉体粒度下（大颗粒或小颗粒），A、B、C组再生氧化锆预烧结体的相对密度及显气孔率差异均无统计学意义（n P>0.05）。对照组终烧结体弯曲强度为（988.4±129.8） MPa，显著大于大颗粒A、B、C组［分别为（421.2±54.7）、（444.2±70.1）、（427.5±68.4） MPa］和小颗粒A、B、C组［分别为（750.1±74.1）、（777.2±95.5）及（746.7±73.0） MPa］（n P<0.05）；小颗粒A、B、C组弯曲强度均分别显著大于相应大颗粒A、B、C组（n P<0.05）。n 结论:与大颗粒再生氧化锆粉体相比，小颗粒再生氧化锆粉体可有效改善再生氧化锆终烧结体的弯曲性能，预烧结升温速率对再生氧化锆性能没有影响。“,”Objective:To evaluate the effects of pre-sintering heating rate and powder size on dental recycled zirconia.Methods:Recycled zirconia powders were sieved to obtain the large (50 μm0.05). When the pre-sintering heating rates were 2 ℃/min, 5 ℃/min, and 8 ℃/min, the flexural strengths of the large-particle recycled zirconia were (421.2±54.7), (444.2±70.1) and (427.5±68.4) MPa, the flexural strengths of the small-particle recycled zirconia were (750.1±74.1), (777.2±95.5) and (746.7±73.0) MPa, respectively. The flexural strength of commercial zirconia was (988.4±129.8) MPa. The flexural strengths of the recycled zirconia were significantly lower than that of the commercial zirconia (n P<0.05). At the same pre-sintering heating rate, the flexural strengths of the small-particle recycled zirconia were significantly higher than that of the large-particle recycled zirconia (n P<0.05).n Conclusions:Compared with the large particles, small-particle recycled zirconia powders can effectively improve the properties of recycled zirconia, while the pre-sintering heating rate has no effect on the properties of the recycled zirconia.