摘要目的:比较二维口内照片和三维数字模型分析上前牙美学参数的差异，为口腔美学诊疗提供参考。方法:2024年1至2月于武汉大学口腔医（学）院口腔医学本科生中招募志愿者100名。通过口内扫描仪获取牙列三维数字模型，数码相机拍摄正面二维口内照片。分别测量三维数字模型和二维口内照片上颌双侧中切牙、侧切牙、尖牙长度和宽度（三维模型组和二维照片组），计算两组各牙位上前牙宽长比，在二维口内照片和三维模型正面视图中计算相邻前牙正面投影宽度比。结果:二维照片组上颌侧切牙宽度［（5.85±0.60）mm］、尖牙宽度［（4.73±0.71）mm］、尖牙长度［（8.72±0.96）mm］均显著小于三维模型组［分别为（6.65±0.59）、（7.76±0.60）、（8.90±0.86）mm］（ t=-18.24， P<0.001； t=-54.43， P<0.001； t=-4.40， P<0.001），其余牙长度或宽度两组差异均无统计学意义（ P>0.05）。二维照片组侧切牙、尖牙宽长比（分别为0.74±0.08、0.55±0.08）均显著小于三维模型组（分别为0.84±0.09、0.88±0.09）（ t=-19.68， P<0.001； t=-50.21， P<0.001），两组中切牙宽长比差异无统计学意义（ P>0.05）。二维照片组侧切牙与中切牙正面投影宽度比、尖牙与侧切牙正面投影宽度比（分别为0.72±0.06、0.85±0.11）均显著小于三维模型组（分别为0.75±0.06、0.89±0.11）（ t=-9.31， P<0.001； t=-6.58， P<0.001）。 结论:美学区牙齿的二维测量与三维测量结果存在差异，差异大小因其在牙弓中的位置不同而不同。进行上前牙测量分析时需根据目标牙位选择合适的方法。

abstractsObjective:To assess the accuracy of two-dimensional (2D) photographs in measuring esthetic parameters of the maxillary anterior teeth by comparing them with measurements obtained from three-dimensional (3D) dental models.Methods:A total of one hundred volunteers (49 males, 51 females, aged 18-23 years) were recruited from School and Hospital of Stomatology, Wuhan University from January to February 2024. 3D digital models of their dentitions were obtained using an intraoral scanner, and standardized frontal 2D intraoral photographs were captured with a digital camera. The lengths, widths and width/length ratio of the bilateral incisors, lateral incisors and canines were measured on both the 3D digital models and the 2D intraoral photographs. The width ratios of adjacent maxillary anterior were also calculated on the 2D intraoral photographs and the frontal view of 3D digital models.Results:The widths of lateral incisors [(5.85±0.60) mm] and canines [(4.73±0.71) mm] and the lengths of canines [(8.72±0.96) mm] in the 2D intraoral photographs were significantly lower than those in 3D digital models [(6.65±0.59), (7.76±0.60), (8.90±0.86) mm] ( t=-18.24, P<0.001; t=-54.43, P<0.001; t=-4.40, P<0.001), while there were no significant differences in the lengths and widths of the other teeth ( P>0.05). The width/length ratios measured from the 2D intraoral photographs for the lateral incisors and canines (0.74±0.08, 0.55±0.08) were significantly lower than those measured in the 3D digital models (0.84±0.09, 0.88±0.09) ( t=-19.68, P<0.001; t=-50.21, P<0.001), and the width/length ratio of the central incisors showed no significant difference between the two groups ( P>0.05). The width ratios of canines/lateral incisors and lateral incisors/central incisors measured on the 2D intraoral photographs (0.72±0.06, 0.85±0.11) were significantly smaller than those measured in the frontal view of 3D digital models (0.75±0.06, 0.89±0.11) ( t=-9.31, P<0.001; t=-6.58, P<0.001). Conclusions:There is a difference between 2D and 3D measurement results of teeth in the esthetic area and the magnitude of the difference varies with their position in the dental arch. When analyzing the measurement of the anterior teeth, it is necessary to choose the appropriate method according to the target tooth position.