Schwass D R, Swain M V, Purton D G, Leichter J W
Department of Oral Rehabilitation, University of Otago, Dunedin, New Zealand.
Caries Res. 2009;43(4):314-21. doi: 10.1159/000226230. Epub 2009 Jun 24.
Desktop microcomputed tomography (micro-CT) offers a non-invasive 3-dimensional analysis of structures and their physical properties. To date, the use of micro-CT has mostly involved qualitative observations, with the extent of quantitative analysis relying on automated internal calibration by the micro-CT control software. However, the value of such calibration is limited by machine drift. For an accurate quantitative use of micro-CT, it is recognized that external means of calibration are needed. A novel system of calibration standards, also known as 'phantoms', is presented. A range of low mineral concentration phantoms involving triethylene glycol dimethacrylate/glycerolate dimethacrylate resin mixed with commercial pure hydroxyapatite (HAP), from 0.07 to 1.05 g/cm(3), was fabricated. Sintered HAP was impregnated with the same resin, producing phantoms with medium-level mineral concentrations up to 1.90 g/cm(3). These phantoms were easy to create, proved accurate and stable with repeated use, and were found to mimic the composite nature of dental enamel and dentine structures under investigation.
桌面式微型计算机断层扫描（显微CT）能够对结构及其物理特性进行非侵入性三维分析。迄今为止，显微CT的应用主要涉及定性观察，定量分析的程度依赖于显微CT控制软件的自动内部校准。然而，这种校准的价值受到机器漂移的限制。为了准确地定量使用显微CT，人们认识到需要外部校准方法。本文介绍了一种新型的校准标准体系，也称为“体模”。制备了一系列低矿物质浓度体模，这些体模由三乙二醇二甲基丙烯酸酯/甘油酸二甲基丙烯酸酯树脂与商业纯羟基磷灰石（HAP）混合而成，密度范围为0.07至1.05 g/cm³。将烧结的HAP用相同的树脂浸渍，制备出矿物质浓度高达1.90 g/cm³的中等浓度体模。这些体模易于制作，经反复使用证明准确且稳定，并且发现它们能够模拟所研究的牙釉质和牙本质结构的复合性质。
