NiTi K type hand file (Perfect Medical Instrument Co., Ltd. Shenzhen, China), Contrary to stainless steel files, turning is produced with the buckling method. torsional resistance and bending resistance of files compared to stainless steel files found more successful in comparison. 16 mm of the files are finished It has the edge. Our Work is 25mm long; 15K (white), 20K (yellow), 25K (red), 30 K (blue) files were used. NiTi K type #15, #20, #25, and #30 hand files were used with a quarter-turn pulling motion, respectively.

The ProTaper Next (PTN) system is produced by adding M-Wire alloy to the ProTaper Universal (PU) system. With the M-Wire alloy, it is aimed to increase the flexibility and cyclic fatigue resistance of the files. The combination of three important design features in PTN files, including changing taper on a single file, M-wire technology and offset design, is one of the important features that distinguish it from other files. PTN X1 and X2 files have both an ascending and a descending conical design on a single file; PTN X3, X4 and X5 files have a constant taper from D1-D3, then taper design that tapers off over the rest of their active segments.

They are produced by applying Gold-wire process to the WaveOne (WO) system. The WOG file system exhibits repetitive back-and-forth mutual 'reciprocation' motion during preparation, in contrast to the continuous rotational motion. While rotating 150° counterclockwise during the reciprocating motion, clockwise It turns 30° in the direction of, and after 3 cycles, it completes 1 full cycle. Thus, it contributed positively to the file reaching the apical without applying excessive pressure, increasing the cutting efficiency, and accelerating the coronal movement of the debris. Small (yellow-20/0.07), WO Primary (red-25/0.07), and WOG Medium (green-35/0.06) files were used with the appropriate speed and torque values recommended by the manufacturer (300 rpm and 2.0 Ncm) by applying crown down technique. WOG files were operated in a reciprocating motion (150° counterclockwise, 30° clockwise).

It is used for cleaning and shaping root canals.

Evaluation of the effect on pain after root canal treatment; Parents were trained to use the pain scale; Postoperative pain occurring at the 6th hour was evaluated. All parents participating in the study were blinded to the treatment protocol used for the children. Evaluation of postoperative pain was performed using the VAS . It was explained that the closest score between "0" no pain and "10" severe pain scores should be recorded by the parents.

Evaluation of the effect on pain after root canal treatment; Parents were trained to use the pain scale; Postoperative pain occurring at the 12th hour was evaluated. All parents participating in the study were blinded to the treatment protocol used for the children. Evaluation of postoperative pain was performed using the VAS. It was explained that the closest score between "0" no pain and "10" severe pain scores should be recorded by the parents.

Evaluation of the effect on pain after root canal treatment; Parents were trained to use the pain scale; Postoperative pain occurring at the 24th hour was evaluated. All parents participating in the study were blinded to the treatment protocol used for the children. Evaluation of postoperative pain was performed using the VAS. It was explained that the closest score between "0" no pain and "10" severe pain scores should be recorded by the parents.

Evaluation of the effect on pain after root canal treatment; Parents were trained to use the pain scale; Postoperative pain occurring at the 48th hour was evaluated. All parents participating in the study were blinded to the treatment protocol used for the children. Evaluation of postoperative pain was performed using the VAS. It was explained that the closest score between "0" no pain and "10" severe pain scores should be recorded by the parents.