Prevalence of Sinus Tract in the Patients Visiting Department of Endodontics, Kermanshah School of Dentistry.

INTRODUCTION: Sinus tract is one of the manifestations of chronic dental infections, which is a path for the drainage of the infection and pus. The present study was aimed to investigate the prevalence of sinus tract with dental origin analyze the correlation between sinus tract and related factors. METHODS: This study was conducted on 1527 patients, visiting Kermanshah school of dentistry, in 2014.The related teeth were examined in terms of vitality test and exact location of sinus tract. Moreover, the causes of this lesion and the needs for root canal treatment were assessed in these teeth. Having obtained the data from the patients, analyzed by Mann-Whitney, Chi-square tests. RESULTS: The frequency of sinus tract was 9.89% patients. There was a significant correlation between the prevalence of sinus tract and factors such as age, general health status, location of sinus tract and history of root canal treatment. The prevalence of sinus tract in maxilla was higher than the mandible (p=0.087). The prevalence of sinus tract in the posterior teeth (69.54%) was significantly higher than that of anterior teeth (30.46%) (p=0.000). From 724 teeth with periapical inflammation and radiolucency, 9.89% teeth had odontogenic sinus tract, and 23.42% teeth with history of root canal treatment had sinus tract. CONCLUSIONS: The most common cause of sinus tract incidence was previous root canal treatment. Therefore, clinicians need to pay a more attention to examining the posterior teeth referred for endodontic treatment.