Magnetic resonance imaging of the maxilla and mandible: signal characteristics and features in the differential diagnosis of common lesions

Imaging approach for jaw and maxillofacial bone tumors with updates from the 2022 World Health Organization classification

Jaw and maxillofacial bone lesions encompass a wide variety of both neoplastic and non-neoplastic pathologies. These lesions can arise from various tissues, including bone, cartilage, and soft tissue, each presenting distinct challenges in diagnosis and treatment. While some pathologies exhibit characteristic imaging features that aid in diagnosis, many others are nonspecific. This overlap often necessitates a multimodal imaging approach, combining techniques such as radiographs, computed tomography, and magnetic resonance imaging to achieve a diagnosis or narrow the diagnostic considerations. This article provides a comprehensive review of the imaging approach to jaw and maxillofacial bone tumors, including updates on the 2022 World Health Organization classification of these tumors. The relevant anatomy of the jaw and dental structures that is important for accurate imaging interpretation is discussed.

Radiolucent Jaw Lesions: Imaging Approach

Jaw lesions are a wide array of benign, malignant, and locally aggressive lesions. On radiography, they can appear radiolucent, mixed, or radioopaque. The imaging appearances of radiolucent jaw lesions are markedly overlapping. The role of the radiologist is to formulate a narrow differential diagnosis based on imaging characteristics and aid appropriate management decisions. The aim of this pictorial review is to familiarize the reader with the imaging approach to radiolucent jaw lesions, which form the bulk of jaw lesions in clinical practice.

Virtual implant planning and fully guided implant surgery using magnetic resonance imaging-Proof of principle

OBJECTIVES

To present a workflow of virtual implant planning and guided implant surgery with magnetic resonance imaging (MRI) and virtual dental models without the use of ionizing radiation.

METHODS

Five patients scheduled for implant placement underwent an MR examination at three Tesla using individualized 2D and 3D turbo spin-echo (TSE) sequences and dedicated head coils. The MRI data and virtual dental models derived from either optical model scans or intraoral scans were imported to a virtual implant planning software (coDiagnostiX, Dental Wings, Montreal, Canada). Virtual prosthetic planning and implant planning were performed regarding the hard and soft tissue anatomy. A drill guide was designed on the virtual dental model using computer-aided design (CAD) and manufactured in-house, using a 3D printer (Eden 260V, Stratasys, Eden Prairie, MN, USA).

RESULTS

The MRI displayed all relevant anatomical structures for dental implant planning such as cortical and cancellous bone, floor of the nasal and maxillary sinus, inferior alveolar nerve and neighboring teeth. The manual alignment of virtual dental models with the MRI was possible using anatomical landmarks. Dental implant planning, CAD/CAM of a drill guide and fully guided implant placement were successfully performed.

CONCLUSIONS

Guided implant surgery is feasible with MRI without ionizing radiation. Further studies will have to be conducted to study the accuracy of the presented protocol and compare it to the current workflow of guided surgery using CBCT.