Evaluation of effectiveness of the protaper system and ni-ti hand files in young permanent teeth with micro-computed tomography

The success and reliability of the Ni-Ti rotary systems used in the root canal treatment had proven with several studies. However, there is not enough information present with the use of the Ni-Ti rotary systems in young permanent teeth with closed apices.The purpose of this study was to evaluate the root canal volume changes, unprepared surface area and deviation from the center line of the canal by shaping properties of ProTaper system and Ni-Ti hand files with micro-computed tomography (?CT) in young permanent teeth.In the study, 30 second permanent molar teeth extracted from patients 15-18 years of age were used. 1.Group (Ni-Ti hand files): the root canal preparation was made with the conventional step-back technique with 2.25 % NaOCl irrigation soluotion. 2.Group (ProTaper system): the root canal preparation was made with the crown-down technique with Glyde lubricant gel and 2.25 % NaOCl irrigation soluotion. The data was recorded by ?BT before and after the root canal shaping. In this study, before and after root canal preparation, the root canal volume changes, the percentage differences between these volumes, unprepared surface area ratio of the total surface and amount of deviation from the center line were evaluated with the recorded data and analized statistically.According to the results of this study, the increase of amount and percentage of the root canal volume before and after preparation for all canals in both groups was statistically significant (p<0,001). When the evaluation is made between Ni-Ti hand files group and ProTaper Ni-Ti rotary system group and within groups (narrow and wide canals), for the root canal volume changes, the percentage differences between these volumes, unprepared surface area ratio of the total surface and amount of deviation from the center line; there was no statistically significant difference (p> 0.05).The ProTaper system can be an alternative to preparation with hand files in root canal treatment of young permanent teeth with closed apices, due to shortening the duration of the session in child patients which is a significant advantage.Key Words: ProTaper, Micro Computed Tomogrphy (?BT), Young Permanent Teeth