Korean J Oral Maxillofac Radiol.  2002 Sep;32(3):167-173.

Radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst: with emphasis on CT

• Soh BC
• Heo MS
• An CH
• Choi M
• Lee SS
• Choi SC
• Park TW

Abstract

PURPOSE: To evaluate clinical and radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst (OKC) using clinical data, plain radiographs, and CT.
MATERIALS AND METHODS
25 cases of ameloblastoma and 44 cases of OKC diagnosed in biopsy, were selected from the files stored in Department of Oral and Maxillofacial Radiology, Seoul National University Dental Hospital from 1999 to 2001, and evaluated using following criteria: sex and age, location, shape, border to normal bone tissue, effect to adjacent tissues, homogeneity in the lumen of the lesion, response of the cortical bone, long-to-short length (L/S) ratio of the lesion, and expansion angle of the cortex.
RESULTS
Ameloblastoma and OKC were seen most frequently in third decades and no statistical significance was noted between both sexes. Ameloblastoma occurred most frequently in mandibular angle and ramus area (68%) and OKC at the maxillary molar (34.1%), and mandibular angle and ramus area (43.2%). The root resorption of the adjacent teeth, mandibular canal displacement, and the impaction of teeth were seen more frequently in ameloblastoma than in OKC. The L/S ratio measured in CT was largest in maxillary OKC cases, followed by mandibular ameloblastoma, and mandibular OKC (1.2, 1.8 and 2.4 respectively). The expansion angle of the cortex shows a statistically significant difference between ameloblastoma (48.8degrees) and OKC (31.5degrees).
CONCLUSION
The numeric morphology (L/S ratio) and expansion angle of the cortical bone of the lesion measured in computed tomography can be used to differentiate the ameloblastoma and odontogenic keratocyst.

Keyword

ameloblastoma; odontogenic cysts; tomography; x-ray computed

MeSH Terms

Ameloblastoma*
Biopsy
Bone and Bones
Diagnosis, Differential*
Molar
Odontogenic Cysts*
Root Resorption
Seoul
Tooth