Root canal therapy is usually performed in single or multiple-visit treatment. The choice of single or multiple visit depend on dentist and patient available time. In general dentistry, multiple-visit is widely chosen by dentist whereas endodontic speciality recommend single-visit. In this study we analyzed 120 root canal therapy performed by students, to determine the number of visits needed to achieve treatment from endodontic-cavity-access to root canal filling and its possible, influence in the successful rate. Results showed that globally, 60% of treatments were performed in multiple-visit. Results showed also hat 89.3% of anteriors teeth were performed in single-visit but there is a higher rate of fail: 31.78%. Nevertheless, these results do not condemn endodontic single visit therapy.