E. & Qplus Root Canal Filling Sealing Ability In Vitro Studies

Objectives:The purpose of the study was to compare the apical sealability of E&Qplus system and cold lateral condensation technique in vitro and evaluate the effects of three different sealers and smear layer removal to the sealability of E&Qplus system. Methodology:Part one: sixty-four extracted human single-rooted teeth were distributed randomly in six experimental groups:A1_A2A₃B₁ B₂ B₃(each of 10 teeth) ,one group of two positive controls and one of two negative controls. After all root canals were prepared by using crown-down technique. GroupA₁,A₂,A₃ were filled with E&Qplus system in combination with three different sealers (ADSEAL, cortisomol, Apexit ) respectively. GroupB₁,B₂,B₃ were filled with lateral condensation technique in combination with sealers (ADSEAL, cortisomol,Apexit). Digital radiograghs of each was taken in a bucco-lingual and a mesio-distal direction and the qualities of filling was evaluated. Apical microleakage was evaluated with 2% methylene blue dye penetration. Part two: forty-four extracted maxillary central or lateral incisors were collected and had the crown cut off at the enamelo-cemental junction. Teeth were randomly assigned to four group: G₁( smear layer removed), G₂( smear layer present), G₃ (positive control ),G₄ (negative control). After canal preparation,G1G2were obturated using E&Qplus system and ADSEAL sealer. G₃ was filled with only warm gutta-percha. Removal of the smear layer was accomplished by rinsing with 15%EDTA and 5.25%NaClO. All the roots were in corporated in a model system using Enterococcus faecalis as a microbial marker. Bacterial penetration was monitored for 60 days. Results were analyzed after 30 days and 60 days with Fisher's exact test. Result: The digital X-ray showed there was no difference between cold lateral condensation and E&Qplus technique in a bucco-lingual direction (P>0.05) and E&Qplus technique was better than cold lateral condensation in a mesio-distal direction(P<0.05). The measured results for the distance of dye penetration showed cold lateral technique had greater dye penetration compared with E&Qplus technique(P<0.05). To E&Qplus technique,three sealers had no difference in terms of dye penetration(P>0.05). To lateral condensation technique,the apical sealability of three sealers was different(ADSEAL>Apexit> cortisomol).There was no statistical difference as to bacterial penetration between removal of smear layer and presence of smear layer at 30 days(P>0.05). After 60 days smear layer removal was significantly better in preventing coronal bacterial leakage than the smear layer presence(P<0.05). Conclusion: Under laboratory conditions E&Qplus system had better apical sealability than cold lateral condensation technique. Effect of sealer was smaller to the E&Qplus system than to the cold lateral condensation technique.The smear layer removal reduced the leakage of bacteria through the root canal system filled with E&Qplus system.