Eficácia da irrigação ultrassônica na remoção de diferentes medicações intracanal a base de hidróxido de cálcio e biocerâmicos: um estudo por micro-CT

Abstract

Intracanal medication must be completely removed before obturation, as its residue can prevent the penetration of the sealer into the dentinal tubules and potentially increasing apical leakage. Therefore, this study evaluated the efficacy of ultrasonic irrigation (UI) in removing calcium hydroxide-based (MIC-HC) and bioceramic-based (MIC-BIO) intracanal medications in mandibular premolars. Thus, 24 single-rooted mandibular premolars were selected, accessed, and instrumented. The teeth were scanned using micro-computed tomography (micro-CT) for evaluate the volume of the root canals and the specimens were divided into two experimental groups (n=12): MIC- HC and MIC-BIO. After the insertion of the intracanal medications, a new scan was performed to analyze the volume of intracanal medication using the CTan software. After 14 days, the medications were removed using ultrasonic irrigation, with three activation cycles of 20 seconds each. The teeth were then rescanned to evaluate the percentage of residual intracanal medication. Data normality was assessed using the Shapiro-Wilk test, and statistical comparisons were performed using Student’s t-test (for normally distributed data) or Mann-Whitney test (for non-normally distributed data), with a significance level of P < 0.05. The results showed that ultrasonic irrigation was not able to completely remove the intracanal medication, although it demonstrated high efficacy, removing 99.02% of MIC-HC and 96.4% of MIC-BIO. No statistically significant difference was found between the groups regarding the percentage of residual MIC after the removal protocols (P > 0.05). It was concluded that ultrasonic irrigation is a viable and effective technique for removing calcium hydroxide-based and bioceramic-based intracanal medications in mandibular premolars. However, complete removal of the tested medications was not achieved in any of the specimens.