Abstract: Objective    To analyze common issues and reasons for inadequate capture of nine standardized intraoral photographs during clinical periodontal internship of dental students. Methods    Fifty sets of nine standardized intraoral photographs were collected from 28 eight-year program dental students at the College of Stomatology，Shanghai Jiao Tong University，from the 2018 cohort，during their clinical internship in periodontology. The occurrence rates of 10 common photographing issues were calculated. Further analysis was conducted on issues with occurrence rates ≥ 50%. Results    The occurrence rates of common photographing issues，from highest to lowest，were as follows：coexistence of actual and mirror images：80.0%（40/50）；failure to capture direct frontal view：74.0%（37/50）；incomplete removal of saliva：56.0%（28/50）；incorrect cropping：56.0%（28/50）；insufficient retraction of lips for anterior teeth：52.0%（26/50）；reflection of mirror edges in image：50.0%（25/50）；insufficient gingival exposure：46.0%（23/50）；excessive brightness or darkness：36.0%（18/50）；incomplete capture of teeth：34.0%（17/50）；fogging/saliva/stains on mirror：34.0%（17/50）. Coexistence of actual and mirror images primarily occurred in the posterior teeth region，mainly mirror images coexisting with actual images of tooth/gum or lips/cheeks；failure to capture direct frontal views mainly included midline deviation，lingual/palatal side occlusal surface capture，and posterior teeth captured too mesially；incomplete removal of saliva was predominantly observed on tooth surfaces，interdental spaces，and the floor of the mouth；errors in cropping primarily involved failure to remove actual image and mirror edge；the most common occurrence of insufficient retraction of lips for anterior teeth was in the palatal side images；the reflection of the mirror edge primarily occurred in lingual-side images of the posterior teeth. Conclusion    There are many problems with the nine standardized intraoral photographs taken by dental students in the periodontal clinical internship. During teaching，it is necessary to emphasize the correct methods of mirror placement，lip traction and framing during shooting. Before taking photos，emphasis should be placed on removing saliva on tooth surfaces，interdental spaces，and the floor of the mouth. After photography，it is crucial to stress the standard of photo cropping.

Key words: dental students, periodontal internship, nine standardized intraoral photographs, digital dental photography, teaching

摘要： 目的    分析口腔医学生在牙周临床实习阶段拍摄口内9张规范照片的常见问题及其原因。方法    收集上海交通大学口腔医学院2018级口腔医学专业八年制28名学生在牙周病科临床实习阶段拍摄的口内9张规范照片50组，计算10项常见拍摄问题的发生率，并对发生率≥ 50%的拍摄问题做进一步分析。结果    常见拍摄问题发生率由高至低依次为：实像与镜像共存为80.0%（40/50），未正面摄影为74.0%（37/50），口内唾液未去除干净、裁剪错误均为56.0%（28/50），前牙唇部未拉开为52.0%（26/50），反光板边缘入画为50.0%（25/50），牙龈暴露过少为46.0%（23/50），亮度过亮或过暗为36.0%（18/50），牙未拍全、反光板有雾气/唾液/污渍均为34.0%（17/50）。其中，实像与镜像共存主要发生于后牙区，大多为镜像与牙齿/牙龈实像或与唇颊部实像共存；未正面摄影主要包括中线偏移、舌腭侧偏咬合面拍摄、后牙偏近中拍摄；口内唾液未去除干净的主要部位为牙面、牙间隙及口底；裁剪错误主要为未裁掉实物像、反光板边缘等；前牙唇部未拉开最常见于上前牙腭侧像；反光板边缘入画主要发生在后牙的舌腭侧像。结论    口腔医学生在牙周临床实习阶段拍摄的口内9张规范照片存在较多问题，在教学过程中需重点教授拍摄时反光板使用、口唇牵拉及取景的正确方法，强调拍摄前需去除牙面、牙间隙、口底的唾液及拍摄后照片的裁剪标准。

关键词: 口腔医学生, 牙周实习, 口内9张规范照片, 口腔数码摄影, 教学