Abstract: Objective  To establish an evaluation method for the image quality of periapical radiographs based on target teeth and assess its clinical application effect. Methods  A total of 1 000 periapical radiographs were collected from Beijing Stomatological Hospital, Capital Medical University in 2023. Two oral radiologists independently evaluated and graded from six dimensions: target tooth location, image clarity, horizontal projection angle, vertical projection angle, artifacts, and cut-off. The simple agreement and Gwet's test were used to assess the inter-observer consistency between the two radiologists. Meanwhile, McNemar's test and Wilcoxon signed-rank test were applied to compare the evaluation differences of the same radiologist with and without reference to the target tooth. Results  Across all six dimensions, regardless of whether the target tooth was marked or not, both the simple agreement between the two evaluators and the AC1（agreement coefficient 1）values from Gwet's test were greater than 0.9, indicating extremely high consistency. For the grading results, the simple agreement was all above 0.8, and the AC2 values from Gwet's test exceeded 0.65, showing good overall consistency. When comparing the evaluations of each radiologist with and without target tooth reference, significant differences were observed in the two dimensions of target tooth location and artifacts, as well as in the grading evaluation (P<0.05). When evaluating with reference to the target tooth, more periapical radiographs met the evaluation criteria, and the image quality grading was better. Conclusion  This standard demonstrates good consistency. Compared with the overall evaluation, the target tooth-based specific evaluation of periapical radiographs can further improve the image grading of periapical radiographs.

Key words: periapical radiograph,  , image quality, evaluation criteria, target tooth,  , consistency,  quality control