الفهرس | Only 14 pages are availabe for public view |
Abstract Although cysts of the mandible are easily detected by radiographic images, it is sometimes difficult to differentiate the cysts from odontogenic tumors by conventional radiography. Conventional radiography is important in early detection of these lesions and detect site, size and extension of lesions. Also the relationship of the tooth to the pathologic lesions. CT is superior to plain radiography in expression of bone .The role of CT is the diagnosis of expansion ,destruction of bone , cortical thinning and extraosseous extension. MRI take the upper hand in differentiation between solid and cystic lesions components. This differentiation is useful in younger patients with cystic lesion in which surgical intervention is not indicated such as haemorrhagic bone cyst. On Gd-T1WI odontogenic cysts (odontogenic keratocysts, dentigerous cysts, radicular cysts) show marginal enhancement without enhancement of the inner part of the cyst. This finding is a characteristic feature of the odontogenic cysts which can be differentiated from the odontogenic tumors. Odontogenic tumors such as ameloblastoma show enhancement on Gd-T1WI. The treatment of ameloblastomas is basically different from that of odontogenic cysts due to the higher recurrence rate of ameloblastomas than that of odontogenic cysts . We could not find a great value of diffusion MRI and ADC map in differentiation between the different jaw cystic and cyst-like lesions. Their diffusion weighted images appear similar with overlap in their ADC values. Further studies of high number of cases could lead to another result in the future. |