Imaging characteristics of neoplasms and other lesions of the jawbones

Neoplasm or not? General principles of morphologic analysis of dry bone specimens

Unlike modern diagnosticians, a paleopathologist will likely have only skeletonized human remains without medical records, radiologic studies over time, microbiologic culture results, etc. Macroscopic and radiologic analyses are usually the most accessible diagnostic methods for the study of ancient skeletal remains. This paper recommends an organized approach to the study of dry bone specimens with reference to specimen radiographs. For circumscribed lesions, the distribution (solitary vs. multifocal), character of margins, details of periosteal reactions, and remnants of mineralized matrix should point to the mechanism(s) producing the bony changes. In turn, this allows selecting a likely category of disease (e.g. neoplastic) within which a differential diagnosis can be elaborated and from which a favored specific diagnosis can be chosen.

Nonodontogenic mandibular lesions: differentiation based on CT attenuation

Mandibular lesions are classified as odontogenic and nonodontogenic based on the cell of origin. Odontogenic lesions are frequently encountered at head and neck imaging. However, several nonodontogenic pathologies may also involve mandible and present further diagnostic dilemma. Awareness of the imaging features of nonodontogenic lesions is crucial in order to guide clinicians in proper patient management. Computed tomography (CT) may provide key information to narrow diagnostic considerations. Nonodontogenic mandibular lesions may have lytic, sclerotic, ground-glass, or mixed lytic and sclerotic appearances on CT. In this article, our aim is to present various nonodontogenic lesions of the mandible by categorizing them according to their attenuations on CT.

Visual perception of multilocular radiolucent mandibular lesions quantified by morphometric analysis

OBJECTIVE

The aim of this study was to analyse the visual perceptions of different experts with respect to multilocular radiolucent lesions in circumstances when the diagnosis is either known or unknown.

METHODS

6 radiographs of ameloblastomas (AMELs), keratocystic odontogenic tumours (KOTs), central giant cell lesions (CGCLs) and myxomas (MIXs) were analysed by 16 dental experts [stomatologists/oral surgeons (SS) and dental radiologists (R)]. They delimited the lesions prior to having knowledge of the diagnosis (T1) and after 30 days, when they were aware of the histopathological results (T2). For each image, the following morphometric parameters were calculated: area (A), perimeter (P) and shape factor (SF); after image subtraction procedures (T1 - T2), the exclusive area (EA) of the non-overlapping delimited region was also calculated.

RESULTS

For both groups, the T2 area was larger than the T1, although the EA of the SS group was higher than that of the R group independently of the type of lesion. The SF from the SS group was greater than that from the R group, and at T2 the SF values were higher for both groups. AMELs and MIXs showed larger SF and A values; the SS group tended to have the greatest changes in the delimitations of the lesions at T2.

CONCLUSIONS

The methodology allowed us to quantify differences in the spatial perceptions of professionals. The knowledge of the diagnosis and the expertise of examiners influenced the examiner's perception of the limits of the lesions independently of the actual biological behaviour of the lesion.

Pre-clinical evaluation of a new dental panoramic radiographic system based on tomosynthesis method

OBJECTIVES

The purpose of the study was to compare the image generated by a classic panoramic machine equipped with a cadmium telluride sensor capable of digital tomosynthesis and special software with images produced by other popular panoramic X-ray machines using a charge-coupled device and native software for image capture.

METHODS

Panoramic images were made using a phantom of a human skull on Planmeca ProMax, Planmeca EC Proline, Kodak 8000 and PC-1000. With the last machine we used the PanoACT® software to adjust the entire arch and to adjust the image in selected regions of interest (ROIs). Ten viewers evaluated the images and provided the viewer data. ANOVA for repeated measures was used to compare the means by pairwise comparisons of means.

RESULTS

The image of the entire arch adjusted by the PanoACT® software was statistically superior to the images produced by other machines. The images generated and individually adjusted by PanoACT® were statistically superior to all other images.

CONCLUSIONS

The image generated by the cadmium telluride sensor has great potential and can be processed to create superior images to those taken with other machines. Furthermore, the ROI individual images enhanced by the PanoACT® were superior to the entire arch adjusted by the same software.