Ki67 as a proliferation marker plays a critical role in assessing cellular activity in various pathological tissues, including cystic lesions. Odontogenic keratocysts (OKCs) and radicular cysts (RCs) are two common types of jaw cysts that exhibit distinct biological behaviors, particularly in their proliferative patterns. OKCs are known for their aggressive nature and high recurrence rate, while RCs are typically less aggressive and exhibit lower recurrence risk. By evaluating the expression of Ki67, a nuclear protein linked to cell proliferation, researchers can gain valuable insights into the growth potential and recurrence tendencies of these cysts.

The study involved analyzing 32 biopsy samples from patients with OKCs and RCs, using immunohistochemical techniques to assess Ki67 expression levels. These samples were surgically removed and prepared for histological examination, with Ki67-positive cells quantified in both basal and suprabasal layers of the cystic epithelium. The findings revealed that OKCs exhibited a higher concentration of Ki67-positive cells in the basal layers, while RCs showed proliferative activity in both basal and suprabasal layers. This differential pattern highlights the more aggressive proliferative behavior of OKCs.

The statistical analysis confirmed significant differences in Ki67 expression between the two cyst types, underscoring the importance of this marker in differentiating OKCs from RCs. The confined expression of Ki67 in the basal layer of OKCs, as opposed to the broader distribution in RCs, suggests that OKCs have a higher proliferative potential, contributing to their increased recurrence rates.