Publications [#174114] of G. Allan Johnson

Papers Published
  1. RS Dhariwal, GA Johnson, RM Browne, SL Rowles, Reprecipitation phenomena arising during the preparation of demineralised sections. III Scanning electron microscopic examinations of secondary calcium phosphate deposits., Stain technology, vol. 51 no. 6 (November, 1976), pp. 293-9 .

    Sections of teeth partly demineralized in 10% formic acid were examined by X-ray diffraction, microradiography and scanning electron microscopy. In the undemineralized circumpulpal dentin, the tubules were empty, lying in a matrix containing hydroxyapatite. In the "plume" areas of remineralisation, the tubules were filled with mineral deposits. X-ray diffraction revealed the presence of brushite and monetite in these areas. In the outer layers of dentin the tubules were empty, lying in a matrix containing some residual hydroxyapatite. These findings confirmed that the remineralisation process occurred within the dentinal tubules.