Root canal lengths were determined by an electronic apex locator with a 15-K file R25 and R50 Reciproc files were used at working lengths to complete the canal preparation. During instrumentation, the root canals were irrigated with 2 mL 1% NaOCl. To obtain the first samples, 3 sterile paper points were placed into the root canals beyond the 2-mm root apex and were kept in position for 60 seconds. Thereafter, the paper points were cut 4 mm from the tip30.

Afterward, root canals were dried with paper points, and calcium silicate based medicament was placed in the canals using a file at a distance of 1 or 2 mm less than the root canal length. Next, the coronal cavities were restored with temporary material.

Seven days later, the medication was mechanically removed using a master apical file. Subsequently, root canals were irrigated.The final samples were collected from the interstitial fluid of the apical tissue as previously described.

Root canal lengths were determined by an electronic apex locator with a 15-K file R25 and R50 Reciproc files were used at working lengths to complete the canal preparation. During instrumentation, the root canals were irrigated with 2 mL 1% NaOCl. To obtain the first samples, 3 sterile paper points were placed into the root canals beyond the 2-mm root apex and were kept in position for 60 seconds. Thereafter, the paper points were cut 4 mm from the tip30.

Afterward, root canals were dried with paper points, and calcium hydroxide based medicament was placed in the canals using a file at a distance of 1 or 2 mm less than the root canal length. Next, the coronal cavities were restored with temporary material.

Seven days later, the medication was mechanically removed using a master apical file. Subsequently, root canals were irrigated.The final samples were collected from the interstitial fluid of the apical tissue as previously described.

The samples were taken from the interstitial fluid of the apical tissues using 3 paper points before medicament placement.

Calcium hydroxide based medicament was placed in the canals using a file at a distance of 1 or 2 mm less than the root canal length.

At the second appointment, medicamentswere removed, and second samplingwas performed using the same method.

The RANKL/OPG, TNF alpha, TGF beta, PGE2 levels were measured by the enzyme-linked immunosorbent assay, and their ratio was calculated.

The amounts of cytokines RANKL and OPG were measured using an enzyme-linked immunosorbent assay kit.

The amounts of PGE2 were measured using an enzyme-linked immunosorbent assay kit.

The amounts of TNF alpha were measured using an enzyme-linked immunosorbent assay kit.

The amounts of TGF beta were measured using an enzyme-linked immunosorbent assay kit.

Did the teeth number, age, sex, smoking habit have any effect on pretreatment or posttreatment levels of RANKL/OPG, PGE2, TNF alpha, TGF beta?