Microleakage study of a restorative material via radioisotope methods

ObjectivesTo validate the quantitative method used in the evaluation of microleakage and to evaluate the microleakage of dental restorations using GCP Fill. The null hypothesis was that the restorative system doesn’t have any influence regarding microleakage.MethodsSixty noncarious extracted human molars were cut in two equal halves occlusogingivally and Class V cavities were prepared on the buccal or lingual surfaces of each tooth. The specimens were randomly divided into 4 groups. Two were restored with GCP Fill, while another was restored with Filtek Supreme. The control group was not restored. The specimens were stored in distilled water at 37°C for 7 days before 500 cycles of thermocycling between 5°C and 55°C, dwell time of 30s. The specimens were submersed in a solution of 99mTc-pertechnetate for 3h and the radioactivity was determined. The nonparametric Kruskal–Wallis and Mann–Whitney test with Bonferroni correction at a significance level of 5% were used for statistical analyses.ResultsThere were statistically significant differences between experimental groups and control groups (p<0.05). Apart from these differences, a significant difference was observed between negative and positive control groups (p<0.001). In the control+group there was a large microleakage, and the control-group received minimum counts.ConclusionThe GCP Fill and the Filtek Supreme XTE do not differ as regards microleakage; this technique proved to be simple, quick and fulfilled the objective of a quantitative method in the evaluation of microleakage. Long-term clinical studies need to be carried out to substantiate these results