## 1 Introduction
Although a small percentage of patients preferred conventional intra-office visits, patients were generally satisfied with the use of DM and reported that taking the intra-oral photos required by the system was easy [20]. Similar results were found by a randomized trial in which CA patients treated with the aid of DM required fewer in-office appointments than conventionally treated controls thanks to remote monitoring [22]. However, no study has yet investigated the hypothesis that DM could improve treatment quality. [PERSON] et al. analyzed the changes in weighted peer-assessment rating (PAR) in CA patients treated with and without DM, finding no significant differences between end-of-treatment PAR scores for the two groups [23]. Another feature of DM is that the software can generate remotely reconstructed intra-oral model files, which appear to be accurate as models generated by intra-oral scans. An initial study, published in 2019, evaluated the accuracy of DM intra-oral models with respect to conventional digital intra-oral models on a group of typodonts with Class 1 malocclusion and anterior crowding. Superimpositions of intra-oral models from DM scansand the Itero intra-oral scanner (Align Technology, San Jose, CA, USA) showed that the difference between the two renderings was not statistically significant [24]. Subsequently, [PERSON] and colleagues demonstrated that in vivo DM photographs can successfully be used to generate intra-oral renderings, which were found to be almost as accurate intra-oral scans [25]. In clinical practice, dental models are useful not only for appliance production, but also for taking sagittal, vertical, and transverse measurements to track orthodontic treatment progress. Transverse measurements in both the lower arch and upper arch are fundamental to the diagnostic process. Proper assessment of the transverse dimensions plays a key role not only in achieving occlusal harmony, but also in long-term treatment stability. Distinguishing between skeletal and dentoalveolar transverse discrepancies is essential, as each requires a different therapeutic approach. Moreover, untreated maxillary constriction has been associated with an increased risk of relapse, underscoring the importance of precise and early identification [26; 27; 28; 29]. Transverse deficiency of the upper jaw is a common situation that orthodontists encounter on a daily basis [30]. It is important to assess whether the problem is related to skeletal or dentoalveolar constriction. There are different ways to assess transverse dimensions, including measurements on postero-anterior radiographs or cone-beam computed tomography scans, and clinical evaluation--i.e., for the presence of cross-bites or degree of crowding--or dental cast analysis [26]. Transverse dimensions may be analyzed on plaster casts or on digital models, which have been proven to be reliable for taking measurements [31]. Previous studies used this method to assess linear distances between dental landmarks [32]. Being able to track transverse dimensions during orthodontic treatment could help the clinician to determine whether skeletal or dentoalveolar transverse dimensions require intervention. Hence, remote monitoring could be invaluable in the assessment of transverse dimensions during orthodontic treatment. The accuracy of this approach has been previously investigated by [PERSON] et al., who assessed remote monitoring measurements during rapid palatal expander treatment in a group of children treated via hyrax expander. They reported that DM software is well capable of recognizing cross-bite correction [33]. In addition, [PERSON] et al. assessed the precision of DM software in evaluating transverse linear movements, as compared to measurements taken on dental models, reporting good correspondence between the two sets of measurements [15].