Department of Pediatric Dentistry and Public Health, School of Dentistry, Araçatuba, São Paulo State University (UNESP), Araçatuba, SP, Brazil.
Department of Physics and Chemistry, São Paulo State University (UNESP), Ilha Solteira, SP, Brazil.
Clin Oral Investig. 2019 May;23(5):2345-2354. doi: 10.1007/s00784-018-2674-9. Epub 2018 Oct 8.
To evaluate the effects of hexametaphosphate microparticles (mHMP) or nanoparticles (nHMP) incorporated in glass ionomer cement (GIC) on antimicrobial and physico-mechanical properties, fluoride (F) release, and enamel demineralization.
HMP solutions were obtained at concentrations of 1, 3, 6, 9, and 12%, for screening of antimicrobial activity. Next, mHMP or nHMP at 6, 9, and 12% were incorporated into a resin-modified GIC and the antibacterial activity was evaluated. The resistance to diametral tensile and compressive strength, surface hardness, and degree of monomer conversion as well as F and HMP releases of GICs were determined. Furthermore, specimens were attached to enamel blocks and submitted to pH-cycling, and mineral loss was determined. Parametric and non-parametric tests were performed, after checking data homoscedasticity (p < 0.05).
HMP solutions at 6, 9, and 12% demonstrated the best antibacterial activity. GIC containing HMP showed better antibacterial effects at 9 and 12% for nHMP. Regarding F and HMP releases, the highest levels of release occurred for groups containing 9 and 12% nHMP. With the increase in HMP concentration, there was lower mineral loss. However, the incorporation of mHMP or nHMP in GIC reduced values of physico-mechanical properties when compared to the control GIC.
nHMP improves antimicrobial activity and fluoride release, and decreases enamel demineralization, but reduces the physico-mechanical properties of GIC.
The association of GIC/HMP could be an alternative material for patients at high risk for dental caries and could be indicated for low-stress regions or provisional restorations.
评估六偏磷酸镁微/纳米颗粒（mHMP/nHMP）掺入玻璃离子水门汀（GIC）对其抗菌性能、物理机械性能、氟化物（F）释放和牙釉质脱矿的影响。
将 HMP 溶液制备成 1%、3%、6%、9%和 12%的浓度，用于筛选抗菌活性。然后，将 6%、9%和 12%的 mHMP/nHMP 掺入树脂改性 GIC 中，评估其抗菌活性。测定 GIC 的抗直径拉伸和抗压强度、表面硬度、单体转化率以及 F 和 HMP 的释放。此外，将标本粘贴到釉质块上，进行 pH 循环，测定矿物质损失。在检查数据同方差性（p < 0.05）后，进行参数和非参数检验。
6%、9%和 12%的 HMP 溶液表现出最佳的抗菌活性。含 HMP 的 GIC 中，nHMP 含量为 9%和 12%时，具有更好的抗菌效果。就 F 和 HMP 的释放而言，含有 9%和 12%nHMP 的组释放量最高。随着 HMP 浓度的增加，矿物质损失减少。然而，与对照 GIC 相比，mHMP 或 nHMP 掺入 GIC 会降低其物理机械性能。
nHMP 提高了抗菌活性和氟化物释放，降低了牙釉质脱矿，但降低了 GIC 的物理机械性能。
GIC/HMP 的联合应用可为高患龋风险的患者提供一种替代材料，可用于低应部位或临时修复。
