Discussion
orthodontic, malocclusions
Cephalometric measurement is essential for diagnosis and treatment plan design of patients with malocclusions, which are the most significant procedures in orthodontic clinical work. Orthodontic educators put forward that orthodontic teaching for undergraduates should focus on diagnosis and recognition of problems.
In our study, three cephalometric items measured by two methods were statistically different, while other items were basically similar. These results implied that digital technology could achieve similar results to the traditional method during cephalometric measurement. Additionally, the majority of items measured by digital technology were closer to the standards, including five statistically significant items, which suggested students could achieve more accurate results by digital technology. This may be attributed to the function of digital software to adjust the gray contrast value of X-ray films (Supplementary figure 1), making it easier to identify the unclear points on the printed paper. In addition, the automatic generation of results also helped to avoid evitable errors during manual measurement. These results were in accordance with previous studies, which suggested that the accuracy of digital measurement on 3-dimensional cone beam computed tomography images was basically similar to or even higher than that of manual measurement.
However, in spite of the convenience it provided, the digital technology may lead to a lack of deep understanding of corresponding contents, such as definitions and meanings of these measurement items. The traditional method could better cultivate practical abilities of students and enhance their memory of relevant knowledge. Besides, although the accuracy of some items obtained by digital technology were significantly higher, a few items showed the opposite result (SNA, ANB and NA-PA). The subspinale point (the A point) was associated with these three items, which suggested that the traditional method was more accurate than digital technology in positioning the subspinale point on the lateral cranial radiograph. The subspinale point is the most concave point of the arc from the anterior nasal spine point (the ANS point) to the superior prosthion point (the Spr point). Compared with digital measurement, the advantage of manual measurement is that the arc can be traced on paper, and some auxiliary instruments like ruler and protractor can help to locate the subspinale point (Supplementary figure 2). These results indicated abundant experience was required to identify the subspinale point, reminding both orthodontic educators and students to devote more time and energy to deep learning it.Before the course, the majority of students showed fear towards abstract and complex concepts, assuming cephalometric measurement was difficult to master. However, with instruction and practice, most students could master 50-80% of relevant knowledge, which could result from digital technology realizing visualization of numerous and complicated anatomical markers. Previous studies found that visualization was extremely attractive to young students, and significantly aroused their interest and sense of participation.
This study still had some limitations. For example, the sample size could be further enlarged. Secondly, the measurement time for students were not strictly required, which may have resulted in the underperformances or supernormal performances of students. Thirdly, exploration of student’s attitudes towards digital technology being applied in this course was not sufficient. The mentioned issues needed to be improved may interrupt us from to accurately assessing the real advantages and disadvantages of the appliance of this digital technology. These findings could guide and encourage university orthodontic teachers to apply this technology in cephalometric teaching and pay more attention to considering the position identification of the subspinale point.