Apical periodontitis (AP) is an inflammatory lesion around the apex of a tooth caused by bacterial infection of the pulp canal system. AP appears radiographically as a radiolucent periapical lesion (RPL). The elective treatment for teeth with AP is root canal treatment (RCT). No study is available about the frequency of RPL and RCT in patients with inherited coagulation disorders (ICD). The aim of this study was to investigate the prevalence of RPL and RCT in patients with ICD and control subjects. In a cross-sectional study, the radiographic records of 58 patients with haemophilia A, haemophilia B or von Willebrand's disease (study group) and 58 control subjects were examined. The frequency of RPL and RCT was assessed using digital panoramic radiographs and the Periapical Index. RPL in one or more teeth was found in 67.2% of patients with ICD and in 48.3% of control subjects (odds ratio = 2.20; P = 0.038). At least one RCT was found in 34.5% and 65.5% of subjects in the study and control groups respectively (odds ratio = 0.28; P = 0.001). Multivariate logistic regression analysis indicated that subjects with ICD had RPL with higher likelihood than control subjects (odds ratio = 7.4; P = 0.0005). Patients with ICD disorders showed a significantly higher prevalence of RPL and lower frequency of RCT than control patients.