Mineralization of Sialoliths Investigated by Ex Vivo and In Vivo X-ray Computed Tomography

Microsc Microanal. 2019 Feb;25(1):151-163. doi: 10.1017/S1431927618016124. Epub 2019 Feb 4.

Abstract

The fraction of organic matter present affects the fragmentation behavior of sialoliths; thus, pretherapeutic information on the degree of mineralization is relevant for a correct selection of lithotripsy procedures. This work proposes a methodology for in vivo characterization of salivary calculi in the pretherapeutic context. Sialoliths were characterized in detail by X-ray computed microtomography (μCT) in combination with atomic emission spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Correlative analysis of the same specimens was performed by in vivo and ex vivo helical computed tomography (HCT) and ex vivo μCT. The mineral matter in the sialoliths consisted essentially of apatite (89 vol%) and whitlockite (11 vol%) with average density of 1.8 g/cm3. In hydrated conditions, the mineral mass prevailed with 53 ± 13 wt%, whereas the organic matter, with a density of 1.2 g/cm3, occupied 65 ± 10% of the sialoliths' volume. A quantitative relation between sialoliths mineral density and X-ray attenuation is proposed for both HCT and μCT.

Keywords: X-ray attenuation; composition; computed tomography; lithotripsy efficiency; lithotripsy methods; multimodal management; sialoliths.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium Phosphates / analysis
  • Humans
  • Lithotripsy / methods
  • Microscopy, Electron, Scanning / methods
  • Microscopy, Electron, Transmission / methods
  • Minerals / analysis
  • Salivary Gland Calculi / chemistry
  • Salivary Gland Calculi / diagnostic imaging*
  • Salivary Gland Calculi / pathology*
  • Submandibular Gland
  • Tomography, Spiral Computed / methods
  • Tomography, X-Ray Computed / methods*
  • X-Ray Diffraction / methods
  • X-Ray Microtomography / methods

Substances

  • Calcium Phosphates
  • Minerals
  • whitlockite