RESUMO
The aim of this study was to establish radiographic criteria for early diagnosis of cystic changes in dental follicles associated with impacted third molars and thereby prevent the development of a pathological cyst and its associated complications. This case control study was performed involving 20 cases of impacted third molars with follicle size measuring <2.5mm and 4 controls with follicle size measuring >3mm, as measured on panoramic radiographs, followed by histopathologic evaluation of the follicles for cystic changes. 55% of follicles associated with impacted third molars, with pericoronal radiolucency less than 2.5mm actually showed presence of stratified squamous epithelium consistent with a dentigerous cyst. Thus on the basis of the results obtained in this study, it was concluded that a pericoronal radiolucency associated with impacted third molar and measuring less than 2.5 mm in the greatest dimensions should be considered as a potential source for the development of a dentigerous cyst when seen in an OPG