Cholesterol crystals in periapical lesions of root filled teeth.

AIM: To determine the prevalence of cholesterol crystals in periapical biopsies and to evaluate the correlation between cholesterol crystals in periapical biopsies and age, gender, location of the periapical lesion, pathologic diagnosis and lesion size. METHODOLOGY: The biopsy report database (Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand) during 2005-2014 was reviewed. The prevalence of cholesterol crystals in the periapical lesions of root filled teeth was determined. Pathological diagnosis, patients' age, gender and the location (maxilla or mandible) of the periapical lesion were obtained from treatment records. The area of the lesion from the periapical radiograph before surgery was calculated using ImageJ software. Univariate and multivariate logistic regression analyses were used to determine the association between independent variables and the presence of cholesterol crystals. RESULTS: The overall prevalence of cholesterol crystals was 20.31%. The periapical biopsies >100 mm(2) in size on periapical films had a significantly greater prevalence of cholesterol crystals than those <100 mm(2) (P = 0.005). The biopsies diagnosed as radicular cysts had a significantly greater prevalence of cholesterol crystals than the biopsies with other diagnoses (P < 0.001). A pathological diagnosis of radicular cyst was the variable with the strongest association with the presence of cholesterol crystals (P < 0.001; adjusted OR, 12.39). CONCLUSIONS: Presence of cholesterol crystals was associated with periapical lesion diagnosed as a radicular cyst and lesion >100 mm(2) in area. Age, gender and location of the lesion did not influence the presence of cholesterol crystals.