Fracture Resistance of Class II MOD Cavities Restored by Direct and Indirect Techniques and Different Materials Combination

Abstract

This study aimed to evaluate the fracture resistance of class II MOD cavities restored using different techniques and materials. Sixty extracted maxillary molars were selected and standardized class II MOD cavities were prepared using a custom-made paralleling device. The specimens were divided into four groups based on the restoration technique used: Group 1 (direct resin composite), Group 2 (short-fiber-reinforced composite resin), Group 3 (composite polyethylene fiber reinforcement), and Group 4 (CAD/CAM resin inlays). Fracture resistance was assessed for each group after thermocycling aging for 10,000 cycles. The mode of fracture was assigned to five types using Burke’s classification. To compare the fracture force among the tested materials, a paired sample t-test was performed. The significance level for each test was set at p < 0.05. Significant differences in fracture resistance were observed among the different restoration techniques. CAD/CAM inlays (2166 ± 615 N), short-fiber-reinforced composite resin (2471 ± 761 N), and composite polyethylene fiber reinforcement (1923 ± 492 N) showed superior fracture resistance compared to the group restored with direct resin composite (1242 ± 436 N). The conventional resin composite group exhibited the lowest mean fracture resistance. The choice of restoration material plays a critical role in the clinical survival of large MOD cavities. CAD/CAM inlays and fiber-reinforced composites offer improved fracture resistance, which is essential for long-term success in extensive restorations.

Fracture Resistance of Direct versus Indirect Restorations on Posterior Teeth: A Systematic Review and Meta-Analysis

“…There was no statistically significant difference in fracture resistance between direct and indirect restorations when composite is used for the restoration of posterior teeth (WMD: −7.09 [95%CI: −129.96, 145.76]; p = 0.16) (Figure 3). [24,26,27,29,31,40,42,45,47].…”

“…There was no statistically significant difference in fracture resistance between direct composite and indirect ceramic restorations (WMD: 18.87 [−212.04, 249.78]; p = 0.87) (Figure 4). [24,26,27,29,31,40,42,45,47].…”

Mechanical Performance of Extensive Restorations Made with Short Fiber-Reinforced Composites without Coverage: A Systematic Review of In Vitro Studies

“…However, due to their physical limitations, clinical failure may occur in the case of extensive restorations. The two most concerning problems with conventional particulate filler composites (PFCs) are polymerization shrinkage [ 11 , 12 , 13 , 14 ] and that—even though they are brittle, strong materials—they lack fracture toughness [ 15 ]. The problem of low fracture toughness is particularly evident in larger direct restorations, as the volume of the material increases.…”

“…Short-fiber-reinforced composite (SFRC) materials seem to offer a solution to this problem, as these materials are much closer to dentine in terms of their physical parameters [ 16 ]. In previous studies, it has been shown that even deep MOD cavities can be reinforced by the application of SFRCs in direct restorations [ 15 , 20 ]. Due to this reinforcing effect, in recent years, numerous innovative restoration techniques and materials have appeared.…”

“…In previous studies, it has been shown that even deep MOD cavities can be reinforced by the application of SFRCs in direct restorations [15,20]. Due to this reinforcing effect, in recent years, numerous innovative restoration techniques and materials have appeared.…”