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Introduction: Dental-dedicated magnetic resonance imaging (ddMRI) is emerging as a radiation-free imaging modality capable of visualizing both soft and mineralized tissues relevant to orthodontic diagnosis. Advances in coil technology and ultrashort echo-time sequences have expanded MRI’s suitability for hard-tissue imaging, positioning ddMRI as a potential alternative to cone-beam computed tomography (CBCT).
MRI acquisition and image processing workflow: A standard ddMRI workflow includes an initial low-resolution scout scan for anatomical localization, followed by a high-resolution three-dimensional acquisition covering the maxillofacial region. Scout images are commonly acquired using T1-weighted gradient-echo sequences, providing rapid anatomical orientation. Compressed sensing techniques are frequently employed to reduce acquisition time without substantial loss of image quality, resulting in total examination times typically under 10 minutes, including patient setup.

Rationale: This review synthesizes current developments in ddMRI, with particular emphasis on image acquisition and processing in dentomaxillofacial imaging. Visualization of facial hard tissues and anatomical landmarks is essential for orthodontic diagnosis and treatment planning. A key technological advancement enabling ddMRI is the use of ultrashort echo-time (UTE) and zero echo-time (ZTE) sequences, which allow signal detection from tissues such as enamel, dentin, and cortical bone, in addition to soft tissues.
Evidence and current limitations: Current evidence demonstrates that ddMRI enables accurate evaluation of impacted teeth, temporomandibular joint anatomy, airway volume, growth-related structures, periodontal conditions, and pulpal health, without exposure to ionizing radiation. Technological innovations now support high-resolution three-dimensional datasets suitable for digital orthodontic analysis. However, challenges remain, including motion susceptibility, acquisition time, limited accessibility, and the need for standardized imaging and measurement protocols.

Conclusion:ddMRI represents a significant step toward comprehensive, radiation-free orthodontic imaging. With its expanding capabilities, it offers valuable diagnostic information for clinicians and researchers, particularly in paediatric orthodontics and temporomandibular joint evaluation. Broader clinical adoption will depend on continued workflow optimization, reliability studies, the establishment of standardized clinical protocols, and the maintenance costs of the machines.