Marginal Adaptation of Bulk Fill Composite Resins

Objectives: To compare the marginal adaptation of several bulk-fill composite resins (list in the Table).
Methods: Typodont teeth with Class II preparations (4mm*5mm*5mm/bucco-lingual x mesio-distal x depth) were cleaned and coated with Optibond Solo Plus adhesive prior to being restored with each composite in one single increment of about 5 mm depth. The composite was cured first from side then from top for 10s each using a Demi Plus curing light. The restored specimens were sectioned in the mesial-distal direction and the entire margin was examined for gap formation (only the margin with a gap greater than 10 microns wide is counted as the gap length) using Leica Microscopes (S9i & DM6). The adaption is calculated by the ratio of total non-gap length to total margin length for each specimen (n=6). Statistical analysis was performed using One-way ANOVA and Tukey’s method for pair-wise comparison to determine significant differences among groups (p<0.05).
Results: The marginal adaptation of bulk-fill composite resins are summarized in following Table. ANOVA analysis revealed that SonicFill 3 achieved comparable (p>0.05) marginal adaptation to that of bulk-fill flowable and significantly (p<0.05) better than Filtek One Bulk Fill. In comparison to Tetric EvoCeram Bulk Fill, SonicFill 3 didn’t show significant difference in terms of marginal adaptation, but indicated higher percentage samples with gap-free margins.
Conclusions: Because of the unique rheological behavior of SonicFill 3 in response to sonic energy that enables good flowability, SonicFill 3 is able to achieve excellent marginal adaptation, which is critical to minimize the risk of microleakage for bulk-filled restorations.