Sundberg M, Friskopp J
Scand J Dent Res. 1985 Feb;93(1):30-8. doi: 10.1111/j.1600-0722.1985.tb01305.x.
Selected area electron diffraction of sections and individual crystal fragments of human dental calculus has demonstrated that octacalcium phosphate, hydroxyapatite and whitlockite form the inorganic part of both supragingival and subgingival dental calculus. However, the major constituents in supragingival calculus are platelet-shaped crystals of octacalcium phosphate and needle-shaped crystals of hydroxyapatite, while bulk crystals of whitlockite is the predominant component in subgingival calculus. The subgingival samples seemed to be better crystallized than the supragingival ones. The results obtained by the electron optical and X-ray powder investigations are in good agreement.
对人类牙结石切片及单个晶体碎片进行的选区电子衍射表明，磷酸八钙、羟基磷灰石和白磷钙矿构成了龈上和龈下牙结石的无机部分。然而，龈上牙结石的主要成分是磷酸八钙的片状晶体和羟基磷灰石的针状晶体，而白磷钙矿的块状晶体是龈下牙结石的主要成分。龈下样本似乎比龈上样本结晶更好。通过电子光学和X射线粉末研究获得的结果吻合良好。
