Objective

This study evaluated the potential combined effects of nanohydroxyapatite and proanthocyanidin on the remineralization and collagen stabilization of demineralized dentin.

Methods

Seventy-five coronal dentin beams (6 × 1 × 1 mm³) were randomly allocated into five experimental groups (n = 15): Sound (no treatment), Control (pH-cycling), nHAp (nanohydroxyapatite), nHAp_PA (Proanthocyanidin-functionalized nanohydroxyapatite), and PA (proanthocyanidin) treatments. The sound group (negative control) were immersed in distilled water over the experimental period. The remaining groups were submitted to a pH-cycling process for 14 days. Following the de-re mineralization process, specimens corresponding to the control group (positive control) were immersed in distilled water whereas the test groups were immersed in 1 mL of respective solution treatment (nHAp, nHAp_PA, or PA) for 1 min. The dentin samples were analyzed to determine their chemical composition (ATR-FTIR and Thermogravimetric) and mineralogical (XRD) characteristics as well as their mechanical response, obtained by three-point bending test.

Results

Higher phosphate content (v₄ PO₄: ATR-FTIR) and amount of mineral (XRD) was observed in the nHAp_PA group. Furthermore, a larger induction of collagen cross-links (ATR-FTIR) and %Organic Matter (TGA) would indicate the PA incorporation and the achievement of dentin matrix stability. These effects on dentin properties were related to increasing flexural strength (MPa), demonstrating that 15% w/v nHAp_PA treatment improved the mechanical properties of the samples.

Significance

nHAp_PA shows significant potential for promoting remineralization while improving collagen stability into demineralized dentin in a clinically feasible period of 1 min.

中文翻译：

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原花青素功能化羟基磷灰石纳米颗粒作为牙本质生物改性剂

客观的

本研究评估了纳米羟基磷灰石和原花青素对脱矿牙本质的再矿化和胶原稳定的潜在联合作用。

方法

七十五根冠状牙本质梁（6 × 1 × 1 mm ³) 随机分配到五个实验组 (n = 15)：声音（无处理）、对照（pH 循环）、nHAp（纳米羟基磷灰石）、nHAp_PA（原花色素功能化纳米羟基磷灰石）和 PA（原花色素）处理。在整个实验期间，健全组（阴性对照）浸入蒸馏水中。其余组进行 14 天的 pH 循环过程。在去re矿化过程之后，将对应于对照组（阳性对照）的标本浸入蒸馏水中，而测试组则浸入1mL各自的溶液处理（nHAp、nHAp_PA或PA）中1分钟。分析牙本质样品以确定它们的化学成分（ATR-FTIR 和热重）和矿物学（XRD）特性以及它们的机械响应，

结果

在 nHAp_PA 组中观察到更高的磷酸盐含量 ( v ₄ PO ₄ : ATR-FTIR) 和矿物质 (XRD) 量。此外，胶原交联 (ATR-FTIR) 和有机物百分比 (TGA) 的更大诱导将表明 PA 掺入和牙本质基质稳定性的实现。这些对牙本质性能的影响与弯曲强度 (MPa) 的增加有关，表明 15% w/v nHAp_PA 处理改善了样品的机械性能。

意义

nHAp_PA 显示出促进再矿化的巨大潜力，同时在临床上可行的 1 分钟内提高胶原蛋白稳定性进入脱矿牙本质。