Comparison of the Time and Accuracy of Intraoral Scans Performed by Dentists, Nurses, Postgraduates, and Undergraduates.

OBJECTIVE: This study aimed to assess the scanning time (ST) and accuracy of 10 repeated upper and lower dentition scans by four groups of operators with different professional backgrounds. METHODS: There were a total of 32 participants, including dentists, nurses, postgraduates, and undergraduates (n=8). They received the same training about intraoral scanning and then performed 10 repeat scans on the plaster maxillary and mandibular dentition models in a manikin head, with the first five scans being the T1 phase and the last five scans being the T2 phase. Each ST was recorded. Trueness and precision were evaluated by root mean square (RMS) value gained from alignments of corresponding virtual models. For statistical analysis, the paired-sample t-tests, one-way ANOVA, and Pearson correlation tests were employed (alpha=0.05). RESULTS: Limiting the comparison in scan phase and scan target the sequence of STs for the four groups was the same (p<0.05), by which undergraduates, postgraduates, nurses, and dentists were in descending order. Undergraduates gained the best precision, followed by postgraduates, dentists, and nurses, in both maxillary and mandibular scanning (p<0.05). Compared with corresponding items of the T1 phase, the trueness of the T2 phase was much higher (p<0.05), while the ST of the T2 phase was much shorter (p<0.05). CONCLUSIONS: The operator's professional background affects the precision and scanning time but not the trueness. Most dental personnel have good access to the intraoral scanner. As the number of scans increased, the accuracy and scanning efficiency also improved.