The Effect of Using Different Single File Systems With Coronal Flaring Instruments on Postoperative Pain

Pain after root canal treatment is an important problem that affects the quality of life of patients. Common factors affecting the formation of pain after root canal treatment include insufficient root canal shaping, irrigation solution extrusion, intracanal medicament extrusion, hyperocclusion, missed canals, presence of pre-procedural pain, presence of periapical pathology, and extrusion of apical debris . It has been reported that the file systems and instrumentation technique used in root canal preparation affect apical extrusion, which is the main cause of postoperative pain . It has been reported that single-file systems introduced to the market to shorten root canal treatment time cause less postoperative pain than multi-file systems. However, there are different opinions about the effect of reciprocal and rotational file systems on postoperative pain. It has been reported that coronal flaring during root canal shaping facilitates apical access of instruments and irrigation solution. NiTi instruments generally tend to orient tissue debris coronally, coronal shaping can create a reservoir for collecting debris accumulated in the coronal portion of the root. Therefore, increasing the coronal space for debris reduces the amount of apically removed extrusion. However, single file systems do not have a coronal flaring file and canal preparation is completed with a single file. An increased amount of apical extrusion may occur due to insufficient coronal shaping during canal preparation using single-file systems. In this study, the effect of the use of coronal flaring file together with rotational and reciprocal single file systems on postoperative pain will be investigated, since there are different results about the effects of rotational and reciprocal file systems on postoperative pain, and although it has been reported that coronal flaring reduces apical extrusion, there is no study that determines the effect on postoperative pain. Thus, it is aimed to reduce