Reattachment or restoration? Fracture resistance of uncomplicated crown fractures using various intermediate materials
Australian Endodontic Journal. 2025;51(3):691-698.
ABSTRACT
This study aimed to evaluate the fracture resistance of different bonding materials used in fragment reattachment for uncomplicated crown fractures, compared to direct composite resin restoration. Sixty human maxillary incisors were divided into five groups (n = 12): G1, control; G2, direct composite resin; G3, flowable composite; G4, preheated composite; G5, self-adhesive resin cement. After simulated fractures and thermocycling, fracture resistance was tested using a universal machine. Data were analysed with one-way ANOVA and Tukey's test (α = 0.05). G1 showed the highest resistance (75.7 ± 10.5 MPa); G2 the lowest (44.7 ± 7.9 MPa). G4 and G5 showed significantly higher resistance than G2 (p < 0.001). No significant difference was found amongst G3–G5 (p > 0.05). Preheated composite and self-adhesive resin cement demonstrated improved fracture resistance compared to direct composite resin. Appropriate material selection may enhance the long-term performance of fragment reattachment in uncomplicated crown fractures.
KEYWORDS
bonding · crown fractures · dental trauma · fragment reattachment · traumatic dental injuries
STUDY SUMMARY
This laboratory study on 60 extracted human maxillary incisors compared the fracture resistance of fragment reattachment using three intermediate materials against direct composite resin restoration and an intact control, after simulated fracture and thermocycling. The intact control showed the highest fracture resistance and direct composite restoration the lowest, while preheated composite and self-adhesive resin cement gave significantly higher values than direct composite; the three reattachment materials did not differ significantly from one another. The results describe laboratory fracture resistance rather than clinical survival.