Effects of proanthocyanidin-functionalized hydroxyapatite nanoparticles on dentin bonding Enrich Essvein, Tattiana González López, Santiago Rodríguez Navarro, Alejandro Cifuentes Jiménez, Carolina Cecilia Maravic, Tatjana Mazzitelli, Claudia Checchi, Vittorio Josic, Uros Mazzoni, Annalisa Breschi, Lorenzo Collagen cross-linkers Dentin biomodification Nanomaterials MMPs Zymography Microtensile bond strength Objectives To evaluate the effect of proanthocyanidin-functionalized hydroxyapatite nanoparticles (nHAp_PA) used as pretreatment at different concentrations on the microtensile bond strength (µTBS) and endogenous enzymatic activity (MMPs) on pH-cycled dentin after 24 h and 6 months of artificial aging. Materials and methods Fifty human sound dentin blocks were randomly assigned to 5 groups (n = 10): (i) negative control (no treatment); (ii) positive control (pH-cycling); (iii) pH-cycling + 2% nHAp_PA for 60s; (iv) pH-cycling + 6.5% nHAp_PA for 60s; (v) pH-cycling + 15% nHAp_PA for 60s. A self-etch adhesive was used for bonding procedures before resin composite build-ups. Specimens were tested with the µTBS test after 24 h and 6 months of laboratory storage. The proteolytic activity in each group was evaluated with gelatin zymography and in situ zymography. Data were statistically analyzed (p < 0.05). Results At 24 h, the µTBS of the experimental groups were significantly higher than the controls (p ≤ 0.001), and no differences were observed between different concentrations (p > 0.05). Artificial aging significantly decreased bond strength in all groups (p ≤ 0.008); however, nHAp_PA 2% still yielded higher bonding values than controls (p ≤ 0.007). The groups pretreated with nHAp_PA exhibited lower MMP-9 and MMP-2 activities compared to the positive control group and almost the same enzymatic activity as the negative control group. In situ zymography showed that after 6 months of aging, nHAp_PA 2% and nHAp_PA 6,5% decreased enzymatic activity as well as the negative control. Conclusions Dentin pretreatment with nHAp_PA increased the bonding performance of a self-etch adhesive and decreased MMP-2 and MMP-9 activities after 6 months. 2024-09-03T09:57:52Z 2024-09-03T09:57:52Z 2024-07-24 journal article Enrich-Essvein, T., González-López, S., Rodríguez-Navarro, A.B. et al. Effects of proanthocyanidin-functionalized hydroxyapatite nanoparticles on dentin bonding. Clin Oral Invest 28, 444 (2024). https://doi.org/10.1007/s00784-024-05836-7 https://hdl.handle.net/10481/93831 https://doi.org/10.1007/s00784-024-05836-7 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Springer