In dental radiology, different indications, such as impacted- and supplementary teeth, orofacial clefts, pre-surgical planning among others, warrant 3D imaging [
36‐
38]. With regard to sutural maturation status, there is no linear correlation between chronological or skeletal age and mid-palatal suture fusion [
39]. Cross-sectional imaging can be beneficial to the assessment of the precise maturation stage, facilitating clinical decision making and outcome [
13]. Up-to-date, axial CBCT images present the gold standard for the assessment of sutural maturation status [
13,
17,
18]. As opposed to 2D panoramic images, which are routinely performed in dental medicine, CBCT creates 3D images without superimposition with other anatomic landmarks, allowing for a standardized description of mid-palatal sutures maturation [
40,
41]. However, since children and young adults present a large proportion of the orthodontic patient collective, the medical indication for employing ionizing radiation has to be well-considered [
38]. Children are significantly more vulnerable to long term, stochastic irradiation effects than adults, with radiation risk being inversely proportional with age [
42]. With regard to radiation exposure, pronounced differences have been observed between CBCT units, with dose assessment being particularly challenging in children [
43,
44]. CBCT doses in pediatric dento-maxillofacial imaging range from 103 µSv for upper and lower jaw imaging (FOV 10 × 10, small FOV) to 175 µSv for skull protocols (medium 17 × 11 and large 24 × 19 FOV) [
44]. The lifetime attributable risk is particularly high in skull protocols, which have equally been reported to dramatically increase the likelihood of brain cancer in children [
23,
44]. A further disadvantage seems to be that many dental CBCT units are tailored to usage in adults and many do not have imaging protocols specific for a paediatric population, resulting in elevated radiation doses for the thyroid gland, the eye lenses, the brain, and the salivary glands [
42,
45]. Due to the above-mentioned disadvantages of ionising radiation in pediatric dentistry, there have been increasing efforts to implement non-ionising cross-sectional imaging into clinical routine [
31]. In this pilot study we investigated the suitability of 3T MRI for the conspicuity of the hard palate and its adjacent sutures. A robust intra-, and inter-rater reliability were observed, however, our reliabilities values are not as high as those reported in other CBCT studies, evaluating sutural maturation [
17,
39]. This might be attributed to the image quality of MRI, which is still inferior to CT/CBCT, particularly with regard to spatial resolution. Furthermore, dentists are not accustomed to routinely evaluate MR images, however, with respective training, the skills in evaluating dental MRI could certainly be improved. We consciously inverted the T1w MRI sequences to obtain an image impression that is comparable to CBCT, facilitating the transition from CBCT to MRI for dentists (Fig.
6). Discrepancies with regard to inter-rater reliability, were primarily found in stages B, C and D while stages A and E were scored with relative ease. This might be due to the fact that stages A (an open and wide suture, Figs.
1A,
6A) and E (a completely fused suture, Figs.
1E,
6E) are more likely a visual diagnosis with less differential diagnostic contemplations to be made. In patients with a very high or very thick palate, the respective axial slices are often not appropriate for the visualization of the entire suture in a single image. In those cases, the evaluation of at least two slices per jaw has been described by Angelieri et al. for a valid assessment of the actual anatomy [
17]. We utilized curved MPR reconstructions, which are widely available on MRI scanners and in 3D post-processing tools. Those curved reconstructions and can ease the reading and increase the accuracy of the respective maturation status (Fig.
5). The fact that our approach is based on MRI data, might certainly present a limitation for many dentists, since MRI, as opposed to CBCT, is not readily available in every clinical setting. In addition, the acquisition recording time of 07:26 min is quite long, which leads to an increased risk of movement artefacts and is impractical in clinical orthodontic routine. However, with novel MRI devices and respective protocol optimization using artificial intelligence, acquisition times are likely to decrease in the near future, resulting in patient friendly examination times. Due to the retrospective design of this study the patient collective is comprised of adults only and the respective MR sequences have to be confirmed in paediatric patients to improve clinical validity. The validity of the Angelieri method in general has been questioned and alternative grading methods based on CBCT images e.g. density of the sutural area relative to soft tissues have been introduced [
46]. The presented MRI protocol might, therefore, be helpful to reduce ionizing radiation in other study settings investigating the hard palate and adjacent sutures. The results of the preset pilot study display the feasibility of 3T MRI with a T1w single slab 3D TSE sequence for the depiction of the hard palate and mid-palatal suture. Inversion of the MR images yields a closer resemblance to an image impression comparable to CBCT. Further studies with larger sample sizes, including a pediatric collective, are aimed to improve and standardize non-ionizing imaging in dental radiology.