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UBC Theses and Dissertations

Effectiveness of different irrigation protocols in removing calcium hydroxide from simulated internal root resorptions Fedorova, Ksenia


Introduction: Calcium hydroxide removal from internal inflammatory root resorptions (IRR) is challenging and many different irrigation techniques have been proven ineffective in clearing this medicament completely. Objective: The aim of this study was to compare the effectiveness of different irrigation methods in removing calcium hydroxide in the 3D printed molar tooth model including deep and shallow internal resorptions. Hypotheses: The presence, depth and location of resorption, irrigation method and composition of calcium hydroxide (Ca(OH)₂) do not affect the effectiveness of Ca(OH)₂ removal by different irrigation devices. Methods: 3D printed transparent models with artificial IRR cavities were designed, printed and filled with UltraCal XS or Multi-Cal calcium hydroxide paste. Apices and side vents were sealed with SoundSeal material. Open-ended needle irrigation (ONI) at 5 ml/L and 15 ml/min, double-side-vented needle irrigation (DNI) at 5 ml/min, EndoActivator (EA), PiezoFlow (PF) at 15 ml/min and GentleWave system (GW) with distilled water as irrigant were used to remove Ca(OH)₂ from the root canal system and resorptions at manufacturer recommended maximum irrigation times. 36 groups (n=10) were established. Ca(OH)₂ removal was assessed visually under 4.2 x magnification on dental operating microscope (DOM). The data were statistically analyzed by Chi-Square, Fisher’s exact test, independent t-test and binary logistic regression analysis, with the significance level set at 5%. Results: Bivariate analyses found statistically significant outcome associations with presence, location and depth of resorption, type of irrigation and type of Ca(OH)₂. Binary logistic regression models showed that Ca(OH)₂ removal was associated with four predictors: type of Ca(OH)₂ (OR = 2.022; 95% CI, 1.245 – 3.285), use of GW as irrigation method (OR = 99.502; 95% CI, 44.928-202.348), location of resorption (OR = 1.441; 95% CI, 1.082 – 1.918) and reverse resorption type (OR = 8.774; CI = 95%, 4.988 – 15.402). Overall, GW was the greatest predictor of effective Ca(OH)₂ removal, followed by absence of resorptions, use of Multi-Cal and coronal location of resorption. Conclusions: GentleWave was more effective in removing Ca(OH)₂ from deep and shallow resorptions than other irrigation methods. Removal of Ca(OH)₂ was affected by the presence, depth and location of resorption and type of Ca(OH)₂.

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