Trends in dentomaxillofacial radiology

Abstract

Oral and maxillofacial diagnostic imaging is of paramount importance in dental clinical diagnosis, treatment planning, and follow-up procedures. Periapical radiographic examination and numerous panoramic systems are used in routine clinical dental practice. Cone beam CT is widely used and currently the method of choice in oral and maxillofacial implantology, endodontics, maxillofacial surgery, periodontics, degenerative temporomandibular joint disease, orthodontics, airway studies, sleep disorders, and forensic dentistry. Another innovative laboratory research tool that offers three-dimensional (3D) detailed high-resolution images of in vitro teeth and neighboring structures with submicrometric accuracy is microcomputed tomography. Ultra-high radiation doses, long scanning times, and high costs preclude its routine clinical use. In response to the high demand for a technique that could provide real-time images using a cost-effective, rapid, user-friendly, and portable technique without ionizing radiation, some authors proposed ultrasound imaging methods as an alternative to X-ray imaging techniques. Ultrasonography can be used in the dentomaxillofacial region for various diagnostic purposes such as salivary gland and superficial tissue examination. Recently, dedicated dental magnetic resonance imaging with appropriate software, hardware, sequences, and field of view tailored to fit dentomaxillofacial anatomy was introduced. Lately, 3D printing technologies and their application in dentistry has attracted attention. During 3D printing a given material is added in successive layers to create a 3D object. The application of this technology has the potential to decrease operation time and minimize operator bias and the possibility of procedural errors. Another hot topic regarding dentomaxillofacial radiology is artificial intelligence, which is a field related to computer science dedicated to developing systems or machines that can perform tasks traditionally associated with human intelligence. It is obvious that further investigation and research in the field of dentomaxillofacial radiology will make great contributions to diagnostic imaging for various dental specialties.

Keywords: Artificial intelligence; Cone beam CT; Dental microcomputed tomography; Dentomaxillofacial radiology; Diagnostic imaging; Microcomputed tomography; Three-dimensional printing; Ultrasonography.

Figure 1

Periapical radiographic examination. A: Periapical image taken from a patient with replacement external root resorption visible on the distal root surface of right mandibular first molar tooth. As can be seen, detailed root and bone structures were discernable but limited to a two-dimensional view; B: Bitewing image taken from a patient with alveolar bone destruction between the right maxillary first and second molar teeth along with a proximal caries on the distal surface of the first maxillary right molar.

Figure 2

Panoramic images. A: Patient with fixation screws and no visible alveolar bone defect in the mandibular anterior region on cropped panoramic radiography. Significant bone loss was evident around the right mandibular lateral incisor on cropped periapical radiography; B: A 35-year-old male patient with a vague radiopacity in the maxillary anterior region on cropped panoramic radiography. A clearly depicted inverted mesiodens tooth was evident between the maxillary incisors on cropped periapical radiography; C: Cropped panoramic image of a 55-year-old male patient with aggressive periodontitis and two horizontally impacted canine teeth visible on the mandibular anterior region. Also, a well-defined round Stafne bone cavity can be seen on the right mandibular region extending under the mandibular canal.

Figure 3

Multiplanar reformatted reconstruction images of a 60-year-old male patient requiring implant treatment referred for cone beam CT imaging. Reformatted axial, panoramic, and cross-sectional images obtained at implant planning mode indicated severe maxillary bone resorption.

Figure 4

Diagnostic X-ray images of a 16-year-old female patient with histopathologically confirmed cemento-ossifying fibroma between the mandibular right premolar teeth. A-D: Two-dimensional panoramic X-ray image (A), reformatted axial cone beam CT (CBCT) image (B), reformatted panoramic CBCT image (C), and reformatted cross-sectional CBCT images (D) showed a well-defined lesion. The mixed radiopacity degree of the inner structures of the lesion observed in different CBCT sections was not detectable on two-dimensional panoramic radiography.

Figure 5

Cone beam CT images of mandibular right (upper image) and left (lower image) third molar teeth of a 25-year-old female patient referred for persistent pain on both retromolar sides. Three-dimensional bone model, panoramic, and cross-sectional images showed a dentigerous cyst related to the mandibular right third molar tooth and direct contact of mandibular left third molar tooth root with mandibular canal.

Figure 6

Axial cone beam CT and ultrasonographic measurement images. A and B: Axial cone beam CT (A) and ultrasonographic measurement (B) images of a 25-year-old female patient referred to our clinic with the complaints of pain and swelling of the cheek after meals. The radiopaque lesion on cone beam CT and hyperechoic lesion on ultrasound images in the submandibular region were suggestive of a submandibular sialolithiasis.

Figure 7

Cropped panoramic radiography (left) and laser doppler ultrasonographic image of a 30-year-old female patient referred for slight percussion sensitivity in the right mandibular first molar region. On panoramic radiography, a well-defined radiolucent lesion on the mesial root of the first mandibular right molar was observed. Laser Doppler ultrasonographic evaluation revealed that there was blood flow in the region suggestive of a granuloma, which was proved by histopathological examination.

Figure 8

Open mouth sagittal T1 magnetic resonance image of a 65-year-old female patient with pain and limitation during chewing suggested anterior disc displacement without reduction.

Figure 9

Cone beam CT images. A-C: Intraoral periapical image (A) and three-dimensional printed bone model (B) of a patient from cone beam CT data obtained in order to assess right mandibular anterior lateral tooth for implant placement; C: According to diagnostic images and the three-dimensional bone model, an implant was successfully placed in the anterior lateral incisor region of the patient as can be seen from the postoperative periapical image.