The Evaluation of Restored Proximal Contact Areas with Four Direct Adherent Biomaterials: An In Vitro Study

The aim of this study was to compare the interproximal contact tightness of lateral teeth after restoring adjacent proximal walls with four types of direct adherent biomaterials. Distal and mesial boxes were prepared on 160 artificial right first and second upper molars. Each set of 40 pairs of boxes was restored using one bulk biomaterial: Equia Forte Fil HT (GC), Cention^® Forte (IVOCLAR VIVADENT), Admira Fusion x-tra (VOCO), or 3M^TMFiltek^TM One Bulk Fill. The mean difference in the passing-through force varied from sound to restored surfaces immediately after application, as well as at 7 and 14 days after: Equia Forte Fil HT-4.07 ± 0.01, 4.08 ± 0.01, and 4.11 ± 0.01; Cention^® Forte-3.30 ± 0.01, 3.50 ± 0.01, and 3.56 ± 0.01; Admira Fusion x-tra-4.10 ± 0.01, 4.13 ± 0.01, and 4.13 ± 0.01; 3M^TMFiltek^TM One Bulk Fill-4.08 ± 0.01, 4.09 ± 0.01, and 4.07 ± 0.01 (<i>p</i> < 0.05). The passing-through force of the restored contact areas showed significantly higher values when compared to those for the sound surfaces, and among them, all biomaterials presented similar values, except for Cention^® Forte. The potential clinical relevance of this study relates to better knowing the most appropriate restorative material for large proximal caries on adjacent surfaces from the outset of the treatment protocol.