Purpose: To determine the biological behaviour of common odontogenic cystic lesions by analysing andcomparing bcl-2 expression amongst them. Materials and
Methods: Our study covered 90 formalin fixed paraffinembedded tissue samples: 26 primary cases each of radicular cysts (RC), dentigerous cysts (DC) and odontogenickeratocysts (OKC) and 12 of recurrent OKCs. Bcl-2 expression was analysed immunohistochemically anddata analysis was accomplished using SPSS version 17.0. Means were taken for age while for gender and siteof the lesions frequencies and percentages were determined. The Chi-square test was applied to evaluate anystatistically significant difference of bcl-2 expression in these lesions and p value of ≤0.05 was taken as significant.
Results: All the recurrent OKCs showed a strong positivity for bcl-2 that was absent in all of its primary cases(p value<0.05). Although variation in expression of bcl-2 was not found to be statistically significant betweenRC and DC, however, it became significant when all primary cases of these common odontogenic lesions werecompared.
Conclusions: Recurrent OKC showed comparatively a more aggressive behaviour than their primarycounterparts and also from RC and DC. Bcl-2 proved to be a valuable adjunct in determining aggressive biologicalbehaviour of odontogenic lesions.