To understand the expression of miR-155 in the periodontal ligament cell population of patients with chronic periodontitis.

Periodontal ligament cells from the teeth of patients (n = 11) with chronic periodontitis were isolated and cultured, as were periodontal ligament cells from intact teeth obtained from healthy patients (n = 13) who had been treated with orthodontic extraction (the control group). The expression level of miR-155 in the two groups of periodontal ligament cell populations was detected by real-time fluorescence-based quantitative PCR.

The periodontal ligament cell expression level of miR-155 was significantly higher in the chronic periodontitis group (0.93 ± 0.12) than in the control group (0.76 ± 0.25) (P < 0.01).

miR-155 expression in periodontal ligament cells was obviously stronger in patients with chronic periodontitis.