目的: 对混合牙列儿童的咬合力和咬合接触进行测量分析，初步提供混合牙列个别正常 儿童咬合情况的基线数据。方法: 采用横断面研究，共纳入20例混合牙列个别正常 儿童，其中男童12例，女童8例，年龄在6.5~9.8岁。使用Dental Prescale Ⅱ咬合分析系统进行牙尖交错位时咬合力和咬合接触的测量，包括全牙列最大咬合力(N)及咬合接触面积(mm²)、左右双侧最大咬合力及咬合接触面积、平均咬合压强(MPa)、最大咬合压强(MPa)，并确定咬合力重心位置。对最大咬合力、平均咬合压强、咬合接触面积的性别差异进行分析，比较混合牙列个别正常 儿童咬合的双侧对称性，对咬合数据与年龄、身高、体质量、体重指数(body mass index, BMI)的相关性进行分析。结果: (1) 20例混合牙列儿童在牙尖交错位时平均最大咬合力为(869.18±106.64) N，平均咬合接触面积为(25.19±2.89) mm²，平均咬合压强为(34.37±5.98) MPa，最大咬合压强中位数(P₂₅, P₇₅)为120(120, 120) MPa；(2)左右双侧在最大咬合力、咬合接触面积、平均咬合压强、最大咬合压强上差异无统计学意义(P>0.05)；(3)牙尖交错位时，12例男童和8例女童的平均咬合接触面积分别为(26.71±3.91) mm²和(21.62±3.08) mm²，平均最大咬合力分别为(911.92±145.05) N和(769.47± 116.45) N，差异有统计学意义(P < 0.05)，而平均咬合压强在男童和女童间差异无统计学意义(P>0.05)；(4)牙尖交错位时的最大咬合力与年龄呈弱相关(r=0.219，P=0.046)，与咬合接触面积呈极强的正相关(r=0.949，P < 0.001)，平均咬合压强、最大咬合压强、咬合接触面积与年龄、身高、体质量、BMI均无相关性；(5)20例混合牙列个别正常 儿童的咬合重心均位于磨牙区，最大咬合压强点有7例儿童仅位于第一恒磨牙区，有10例儿童在乳磨牙区和第一恒磨牙区均存在，有3例儿童仅位于乳磨牙区。结论: 混合牙列个别正常儿童在牙尖交错位时的最大咬合力、咬合接触面积、平均咬合压强、最大咬合压强双侧对称性良好；最大咬合力、咬合接触面积存在性别差异，男童大于女童；最大咬合力与咬合接触面积呈正相关。

Objective: To measure and analyze the occlusal force and contact in children with mixed dentition, and to preliminarily provide baseline data on the occlusion of individual normal occlusion children with mixed dentition. Methods: A cross-sectional study was conducted, including 20 children with mixed dentition and individual normal occlusion, consisting of 12 boys and 8 girls, aged 6.5-9.8 years. The Dental Prescale Ⅱ occlusal analysis system was used to measure the occlusal force and contact at the intercuspal position, including the maximum occlusal force (N) and the occlusal contact area (mm²) of the entire dentition, and the left and right sides, average occlusal pressure (MPa), maximum occlusal pressure (MPa), and to determine the position of the center of occlusal force. The gender differences in maximum occlusal force, average occlusal pressure, and occlusal contact area were analyzed, the bilateral symmetry of occlusion in children with mixed dentition and individual normal occlusion was compared, and the correlation between occlusal data and age, height, weight, and body mass index (BMI) was analyzed. Results: (1) The average maximum occlusal force of the entire dentition in the 20 children with mixed dentition at the intercuspal position was (869.18±106.64) N, the average occlusal contact area was (25.19±2.89) mm², the average occlusal pressure was (34.37±5.98) MPa, and the maximum occlusal pressure M(P₂₅, P₇₅) was 120 (120, 120) MPa; (2) There was no statistically significant difference in the maximum occlusal force, average occlusal pressure, maximum occlusal pressure, and occlusal contact area between the left and right sides (P>0.05); (3) At the intercuspal position, the average occlusal contact area for 12 boys and 8 girls was (26.71±3.91) mm² and (21.62±3.08) mm² respectively, and the average maximum occlusal force was (911.92±145.05) N and (769.47±116.45) N respectively, with statistically significant differences (P < 0.05), while there was no statistically significant difference in the average occlusal pressure between boys and girls (P>0.05); (4) The maximum occlusal force at the intercuspal position was weakly correlated with age (r=0.219, P=0.046), and strongly positively correlated with the occlusal contact area (r=0.949, P < 0.001), while the average occlusal pressure, maximum occlusal pressure, and occlusal contact area were not correlated with age, height, weight, or BMI; (5) The center of occlusal force in the 20 children with mixed dentition and individual normal occlusion was located in the molar region, with 7 children having the maximum occlusal pressure point only in the first permanent molar region, 10 children having it in both the deciduous molar region and the first permanent molar region, and 3 children having it only in the deciduous molar region. Conclusion: In children with mixed dentition and individual normal occlusion, the maximum occlusal force, occlusal contact area, average occlusal pressure, and maximum occlusal pressure at the intercuspal position show good bilateral symmetry; there are gender differences in the maximum occlusal force and occlusal contact area, with boys having greater values than girls; the maximum occlusal force is positively correlated with the occlusal contact area.