Evaluation of CT and MRI Imaging Results of Radicular Cysts, Odontogenic Keratocysts, and Dentigerous Cysts and their Contribution to the Differential Diagnosis

AIM

This study aimed to evaluate the contribution of the MRI and CT results to the differential diagnosis of histopathologically different odontogenic cysts.

BACKGROUND

Odontogenic cysts are commonly seen in the jaw bone and their surgical operations have an important place in the practice of maxillofacial surgery; treatment options for these cysts differ according to their histopathology. Differential results that can be obtained from the radiological evaluations of different cyst groups will allow the surgeon to plan a more accurate approach at the beginning of the operation. In this study, computed tomography (CT) and magnetic resonance imaging (MRI) results of different cyst groups were interpreted together with their histopathological diagnosis.

METHODS

CT and MRI results of 17 patients aged between 19-61 were evaluated, whose histopathological diagnosis consisted of 3 radicular cysts (RC), a total of 9 odontogenic keratocysts (OKC) of which 4 were inflamed, and a total of 5 dentigerous cysts (DC) of which one of them was inflammatory.

RESULTS

In the CT scan, all cysts showed lytic, a sclerotic surrounding, and showed MRI peripheral enhancement, whereas solid nodular enhancement was only observed in OKCs. Edema and/or air in the surrounding bone medulla was observed in the infected lesions. OKC was heterogeneous, whereas RC and DC were more homogeneous. Diffusion restriction was observed to be frequent in OKCs. The OKCs were ellipsoidal in appearance and were located parallel to the long axis of the bone, and their dimensions were observed to be larger than the other cysts. OKCs may be accompanied by unerupted teeth. Radicular cysts were located perpendicular to the long axis of the bone and were globular in appearance, and their dimensions were smaller and more homogeneous compared to the OKCs. Dentigerous cysts are also accompanied by an unerupted tooth, and their peripheral enhancement is minimal and homogeneous. However, dentigerous cysts can be dense in content and smaller in size, and ellipsoidal localization is more common than OKCs.

CONCLUSION

In addition to classic panoramic radiography in the evaluation and differential diagnosis of maxillary and mandibular lesions, CT and MRI evaluations can provide helpful information to the surgeon and pathologist in making the diagnosis and may further help plan the operation.

Genotoxicity of fixation devices analyzed by the frequencies of sister chromatid exchange

BACKGROUND

Metal alloys utilized in the management of jaw fractures may exert genotoxic effects. Our purpose was to compare the genotoxicity of intermaxillary fixation devices containing nickel and chromium to that of titanium miniplates utilized in treatment of jaw fractures through the analysis of sister chromatid exchange.

METHODS

In this prospective study, in a total of 28 non-smoker patients (10 females, 18 males; mean age 33.43±10.76; range 15 to 60 years) with jaw fractures, 14 were treated with intermaxillary fixation by administration of nickel-chromium wire and arch bar and 14 with titanium miniplates to investigate the genotoxicity of different metal alloys. The outcome variable was the frequency of sister chromatide exchange in peripheral lymphoctyes, determined through the analysis of venous blood samples obtained preoperatively and 4 to 6 weeks postoperatively.

RESULTS

The frequency of the average sister chromatid exchange was found to be significantly higher in patients treated with the nickel-chromium intermaxillary fixation devices than those treated by titanium miniplates (1.29±0.29 vs. 0.46±0.39, p<0.001).

CONCLUSION

Although titanium miniplate osteosynthesis is an invasive technique in comparison with the nickel-chromium-containing intermaxillary fixation devices, titanium seems to exert less genotoxic effect than the nickel-chromium alloy. However, this finding should be supported in clinical studies with a larger sampling size.