Effect of separated instruments on periapical pH using calcium hydroxide as an intracanal medicament in curved root canals

Abstract

Objective: To evaluate the effect of intracanal separated instruments with different lengths on periapical pH levels using calcium hydroxide (CH) as an intracanal medicament in curved root canals. Materials and Methods: 120 teeth (root canal curvature >25˚) were divided into six groups following the root canal preparation. In Group 1, 2 mm and in Group 2, 4 mm NiTi instruments were separated in the apical portion of the root canals and CH paste was applied. In Groups 3 and 4, no separated instrument but CH was applied. In Groups 5 and 6, neither a separated instrument nor CH. The samples were placed inside a glass tubes with distilled water. pH of this distilled water was measured at different time-points. Results: At all-time points, pH values between the experimental groups were similar except at 1-day (Group 1 < Group 2, P<0.05). At the 2-day and 30-day time points, Group 3 showed higher pH values than Group 1 (P<0.05). At 7-day and 14-day points, pH values were similar. Conclusions: The presence of a separated instrument with different lengths in curved root canals did not have a significant effect on the pH increase caused by CH used as an intracanal medicament.