RESUMO
BACKGROUND/AIMS: Following coronal tooth fracture, keeping the fragment hydrated is of the utmost importance in the tooth fragment bonding technique. The aim of this study was to evaluate the effects of different immersion times in different storage media on multimode adhesive bonding between reattached fragments and teeth. MATERIALS AND METHODS: A total of 195 bovine incisors were fractured and randomized into the following storage groups (n = 15): G0-control group (sound tooth); GA-saline solution: for 1 hour (A1) or 24 hours (A2); GB-artificial saliva: for 1 hour (B1) or 24 hours (B2); GC-coconut water: for 1 hour (C1) or 24 hours (C2); GD-tap water: for 1 hour (D1) or 24 hours (D2); GE-milk: for 1 hour (E1) or 24 hours (E2); GF-dry (dehydration): for 1 hour (F1) or 24 hours (F2). Tooth fragments were then reattached using a multimode adhesive in a self-mode technique with a flowable resin composite. Fracture resistance was evaluated in a universal testing machine under a compressive load (1 mm/min). The data were submitted to two-way analysis of variance and the post hoc Tukey test (5%). RESULTS: The group submitted to the dehydration factor (GF) exhibited a mean value of 599.1 ± 144.2 N, while those submitted to all hydration protocols (GA, GB, GC, GD, GE) exhibited a mean value of 751.8 ± 285.4 N. Dehydration significantly affected the fracture strength values (P = .005). No significant interaction between the rewetting solutions was observed (P > .05). CONCLUSIONS: Hydration of the tooth fragment increased fracture resistance, regardless of the storage solution and/or immersion time.