Besinis Alexandros, van Noort Richard, Martin Nicolas
School of Clinical Dentistry, University of Sheffield, Sheffield, UK.
School of Clinical Dentistry, University of Sheffield, Sheffield, UK.
Dent Mater. 2014 Mar;30(3):249-62. doi: 10.1016/j.dental.2013.11.014. Epub 2014 Jan 17.
This study investigates the potential of a novel guided tissue regeneration strategy, using fully demineralized dentin infiltrated with silica and hydroxyapatite (HA) nanoparticles (NPs), to remineralize dentin collagen that is completely devoid of native hydroxyapatite.
Dentin blocks were fully demineralized with 4N formic acid and subsequently infiltrated with silica and HA NPs. The remineralizing potential of infiltrated dentin was assessed following a twelve week exposure to an artificial saliva solution by means of TEM, EDS and micro-CT. Measurements were taken at baseline and repeated at regular intervals for the duration of the study to quantify the P and Ca levels, the mineral volume percentage and mineral separation of the infiltrated dentin specimens compared to sound dentin and non-infiltrated controls.
Infiltration of demineralized dentin with nano-HA restored up to 55% of the P and Ca levels at baseline. A local increase in the concentration of calcium phosphate compounds over a period of twelve weeks resulted in a higher concentration in P and Ca levels within the infiltrated specimens when compared to the non-infiltrated controls. Remineralization of demineralized dentin with silica NPs by immersion in artificial saliva was the most effective strategy, restoring 20% of the P levels of sound dentin. Micro-CT data showed a 16% recovery of the mineral volume in dentin infiltrated with silica NPs and a significant decrease in the mineral separation to levels comparable to sound dentin.
Demineralized dentin infiltrated with silica NPs appears to encourage heterogeneous mineralization of the dentin collagen matrix following exposure to an artificial saliva solution.
本研究调查一种新型引导组织再生策略的潜力，该策略使用浸润有二氧化硅和羟基磷灰石（HA）纳米颗粒（NPs）的完全脱矿牙本质，使完全不含天然羟基磷灰石的牙本质胶原再矿化。
用4N甲酸将牙本质块完全脱矿，随后用二氧化硅和HA NPs浸润。通过透射电子显微镜（TEM）、能谱仪（EDS）和微型计算机断层扫描（micro-CT），在将浸润后的牙本质暴露于人工唾液溶液12周后，评估其再矿化潜力。在基线时进行测量，并在研究期间定期重复测量，以量化浸润牙本质标本与健康牙本质和未浸润对照相比的磷（P）和钙（Ca）水平、矿物质体积百分比和矿物质分离情况。
纳米HA浸润脱矿牙本质在基线时可使P和Ca水平恢复高达55%。与未浸润对照相比，在12周内磷酸钙化合物浓度的局部增加导致浸润标本中P和Ca水平更高。通过浸入人工唾液用二氧化硅NPs使脱矿牙本质再矿化是最有效的策略，可恢复健康牙本质P水平的20%。Micro-CT数据显示，用二氧化硅NPs浸润的牙本质中矿物质体积恢复了16%，矿物质分离显著降低至与健康牙本质相当的水平。
浸润有二氧化硅NPs的脱矿牙本质在暴露于人工唾液溶液后似乎促进了牙本质胶原基质的非均相矿化。
