Microleakage Assessment of Single Cone Gutta Percha Obturation Technique Using Different Types of Sealers

Abstract

Introduction: Endodontic sealers play a critical role in providing an impervious seal and creating a fluid-tight apical and coronal seal to prevent microleakage which can potentially lead to treatment failure. Voids in the sealer mass have the potential to allow leakage through obturation. They are more serious in single cone (SC) obturation as the volume of sealer used in this obturation is large. Aim: To compare the coronal and apical seal of canals obturated with different root canal sealers and to evaluate gaps or voids occurring in roots filled with different root canal sealers. Materials and Methods: One hundred extracted human upper molars with fully formed and sound palatal roots were used in the study. Sixty teeth were used for microleakage test and the other forty teeth were subjected to voids detection test. The crown of each tooth was decoronated at cement-enamel junction and the palatal root canal was prepared using ProTaper gold rotary instruments. For microleakage testing: Sixty specimens were used and divided into 3 equal groups(n=20) for SC obturation using two different types of epoxy resin sealers AH26 and vioseal sealers respectively and one control group without sealer. All the specimens were exposed dye penetration test using 2% methylene blue dye. Samples were then evaluated under a stereomicroscope to detect the linear measurement of the dye penetration from the apical constriction. For voids detection test: The remaining forty samples were divided into two groups each group (n=20) for SC obturation using AH26 and vioseal sealers respectively. The obturated teeth were sectioned at apical, middle, and coronal third, and area of voids in the sealer was assessed using a stereomicroscope. The collected data was statistically analysis by using Graph Pad Instat software for windows. One-way ANOVA was done for compared time followed by Tukey‘s pair-wise if showed significant for leakage results. Two-way analysis of variance was performed for gap results. Student t-test was done between groups at different regions for gap. Correlation between leakage and gap/voids area was performed by Pearson correlation test. Results showed that for microleakage assessment, the difference in dye penetration microleakage means between groups was statistically significant as revealed by one-way ANOVA test (p < 0.05). Pair-wise Tukey‘s post-hoc test showed non-significant (p>0.05) difference between (AH26 and Vioseal sealers) groups. For gap/voids area area (μm2) for both sealer groups regardless to radicular regions, it was found that vioseal sealer recorded statistically significant higher mean value of gap area than AH26 sealer. Totally irrespective of sealer type it was found that coronal region recorded the highest mean value of gap area followed by apical region mean value. There was a statistically significant direct correlation between leakage and gap/voids area as proved by Pearson correlation test. Conclusion none of the tested root canal sealers could eliminate the dye infiltration or microleakage formation. Single cone gutta-percha combined with AH26 sealer exhibited less microleakage than vioseal sealer. Key words: AH26, Vioseal, root canal sealer, single cone obturation, microleakage, voids