Void and Gap Formation in Canals Prepared with Different Techniques

Objective: The aim of the study was to analyze of void and gap formation in curved root canals instrumented and filled with different techniques by using a micro-computed tomography (micro-CT). Method: Mesial roots of 20 extracted mandibular first molars were used. Root canals (mesiobuccal and mesiolingual) were instrumented with SAF or Revo-S. For the standardization, mesiobuccal canals (n=20) were instrumented with SAF and mesiolingual canals (n=20) were instrumented with Revo-S in each tooth. Canals were filled with qutta-percha and AH Plus sealer using cold lateral compaction (CLC) or thermoplasticized injectable (TT) techniques. Roots were then scanned with a micro-CT, and 3D analysis of void and gap incidence was carried out by using the specialized CT software. Data were analyzed using the unpaired-t and Kruskal-Wallis tests. Result: There was no statistically significant difference between the identified void and gap formation after prepared canals with SAF (p=0.364) or Revo-S (p=0.239). When the used filling techniques are considered independently from the instrumentation techniques, it was found that similar features (p=0.880 and p=0.622). Conclusion:  None of the tested techniques provided void or gap-free fillings. There was no difference between the used instrumentation and filling techniques.