Comparative Evaluation of Microleakage of Two Variables of Glass-Ionomer Cement: An In vitro Study

Introduction: The emergence of nanotechnology, which has become an important research area in dentistry, has made it possible to obtain nano-structured materials with improved properties compared to their basic form. In this work, we have performed an experimental study on natural teeth to evaluate the microleakage of a Ketac (TM) Universal nano-filled GIG in box cavities and compare it to a Ketac (TM) Fil Plus (3M ESPE) conventional GIG. Materials and Methods: 80 Class II cavities were prepared on the mesial and distal surfaces of forty teeth (twenty molars and twenty premolars). The sample was divided randomly into two groups: Group1 with conditioning and Group 2 without conditioning. The mesial cavities were obturated with Ketac (TM) Universal nano-filled GIG and the distal cavities with Ketac (TM) Fil Plus GIG. The teeth underwent thermocycling, followed by infiltration with methylene blue. The teeth roots were inserted into methacrylate resin blocks and then sectioned with a chainsaw in the center of both restorations. After observation with a stereomicroscope, the extent of methylene blue infiltration in each restoration was recorded separately for the cervical surface (from 0 to 2) and the axial surface (from 0 to 3).The Chi-squared test with SPSS20.2 software was used to investigate the score distribution. Results: Results were considered significant if P<0.05. The Chi-square test showed a significant difference between the nano-filled GIG and the condensable GIG. The nano-filled GIG showed less infiltration, and it was found to be more tight than the conventional GIG. Conclusion: The results of the current study suggest that the use of nanotechnology is a promising strategy to improve the clinical performance of GIG. However, this study is limited to an experimental in vitro strategy, which cannot reliably reproduce clinical reality.