Michael J. Pharoah

The evolution and application of dental maxillofacial imaging modalities.

During the last decades, an exciting new array of imaging modalities, such as digital imaging, CT, MRI, positron emission tomography, and cone-beam CT (CBCT), has provided astounding new images that continually contribute to the accuracy of diagnostic tasks of the maxillofacial region. The most recent, cone-beam imaging, is gaining rapid acceptance in dentistry because it provides cross-sectional imaging that is often a valuable supplement to intraoral and panoramic radiographs. The information content in such examinations is high and the dose and costs are low. The increasing trend toward the use of CBCT in dental offices may be expected to result in improved diagnosis, but with increased patient dose and health care costs. Using CBCT as a secondary imaging tool helps optimize health-to-risk ratio.

Radiographic features of segmental odontomaxillary dysplasia: A study of 12 cases

The purpose of the study was to analyze the radiographic features of segmental odontomaxillary dysplasia by studying the radiographs of 12 new cases. With a standard data collection form, the radiographic characteristics were assessed by the two principal investigators who studied available radiographs of all cases. As in previously reported cases, abnormal findings in all patients were confined to the posterior segment of one maxilla. The most common findings in the cases studied were sclerosis and thickening of bony trabeculae, missing permanent premolar teeth, abnormal spacing of primary molars vertical orientation of bony trabeculae, a smaller maxillary sinus, and delayed eruption of permanent posterior teeth. Less commonly observed features were enlarged crowns, roots, and pulps of primary molars, irregular resorption of primary molar roots, mediolateral expansion of the alveolar process, splayed roots of primary molars, and an abnormal medial position of the teeth.

Central giant cell granuloma of the mandibular condyle: a case report and review of the literature

Central giant cell granuloma (CGCG) is a benign intraosseous lesion. The true nature of this lesion is controversial and remains unknown; the three competing theories are that it could be a reactive lesion, a developmental anomaly or a benign neoplasm. Furthermore, the actual aetiology of CGCG is still unclear, although inflammation, haemorrhage and local trauma have all been suggested; it has also been hypothesized that CGCG may have a genetic aetiology. Lesions central to the mandibular condylar head are very rare, with only three documented cases in the English language literature, none of which elaborates on the CT features. In this case report, a 31-year-old male patient complaining of a left pre-auricular mass underwent radiographic investigation. CT images revealed a lesion central to the mandibular condyle and demonstrated features that were highly suggestive of CGCG. The patient underwent surgical curettage, and the subsequent histopathological examination confirmed the diagnosis of CGCG. 3 years after the procedure the patient presented with a recurrence and underwent complete resection of the mandibular condyle with immediate reconstruction. This report presents CT characteristics of a rare occurrence of CGCG of the mandibular condyle, compares it with other published cases and poses the question of the role of radiology in predicting the degree of aggressive behaviour of these lesions before surgery.

Intraosseous mucoepidermoid carcinoma: a review of the diagnostic imaging features of four jaw cases

The purpose of this case series is to present the common features of intraosseous mucoepidermoid carcinoma (IMC) of the jaws in plain film and CT imaging. Two oral and maxillofacial radiologists reviewed and characterized the common features of four biopsy-proven cases of IMC in the jaws in plain film and CT imaging obtained from the files of the Department of Oral Radiology, Faculty of Dentistry, University of Toronto, Toronto, Canada. The common features are a well-defined sclerotic periphery, the presence of internal amorphous sclerotic bone and numerous small loculations, lack of septae bordering many of the loculations, and expansion and perforation of the outer cortical plate with extension into surrounding soft tissue. Other characteristics include tooth displacement and root resorption. The four cases of IMC reviewed have common imaging characteristics. All cases share some diagnostic imaging features with other multilocular-appearing entities of the jaws. However, the presence of amorphous sclerotic bone and malignant characteristics can be useful in the differential diagnosis.

Gorham's disease of the maxilla: a case report

A case of Gorhams disease in the maxilla of a 56-year-old male patient is described. The clinical presentation, radiographic and histopathological features and treatment are presented. A discussion of the current understanding of this rare disease, based on review of the literature, is offered.

Pictorial Essay: Cysts and Cyst-like Lesions of the Jaws

The diverse spectrum of pathologies that can manifest as cystic jaw lesions can present a challenge even for experienced radiologists. Part of the difficulty is that some lesions, particularly those commonly detected on dental radiography, are more familiar to dental radiologists. However, it is not uncommon for medical radiologists to be confronted with these lesions when cross-sectional imaging is performed. This review summarizes the clinical, radiologic, and histopathologic features of selected cystic jaw lesions, including both odontogenic and nonodontogenic diseases. Although not exhaustive, the lesions discussed cover a range of cysts and cyst-like lesions likely to be encountered by the radiologist.

A retrospective analysis of referral patterns for oral radiologic consultation over 3 years in Ontario, Canada

OBJECTIVES To determine the types of practitioners who most commonly refer and the film type and diagnostic entities that are most frequently submitted for oral radiologic consultation in Ontario, Canada. STUDY DESIGN A total of 430 referral letters and responses from 2 Ontario oral radiologists from 2003 to 2005 were analyzed. Data collected included the specialty of the referring practitioner, the film type(s) submitted, the radiographic density of the entity of interest, and the interpretation by the radiologist. RESULTS General practitioners (58.9%) and oral surgeons (21.5%) were the most frequently referring practitioner types, representing 1.2% and 17.1% respectively of each group practicing in Ontario. Also, 18.2% of oral pathologists referred. Panoramic radiographs (79.5%) were included in referrals more often than intraoral radiographs (46.0%). Of the entities, 37.0% were radiopacities, 27.4% were radiolucencies, and 13.5% had mixed radiopaque-radiolucent density. The radiologists interpreted normal features (55.6%) most often. CONCLUSION Panoramic radiographs with normal findings were submitted to oral radiologists for consultation most frequently in Ontario.

Characteristics of an oral and maxillofacial radiology department. Report of the ad hoc Department Characteristics Committee of the American Academy of Oral and Maxillofacial Radiology.

Oral and maxillofacial radiology is a dynamic and multifaceted discipline that plays a critical role in patient care, the education of general dentists and dental specialists, and the academic health of the dental school. Diagnostic and treatment advances in temporomandibular joint disorders (TMD), implants trauma and orthognathic surgery, and craniofacial abnormalities depend heavily on conventional and advanced imaging techniques. Oral and maxillofacial radiology contributes to the education of pre- and post-doctoral dental students with respect to biomedical and clinical knowledge, cognitive and psychomotor skills, and the professional and ethical values necessary to properly prescribe, obtain, and interpret radiographs. The development of an active and successful oral and maxillofacial radiology department, division, or section requires the committment of institutional resources. This document may serve as a guide to dental schools committed to excellence in oral and maxillofacial radiology.