Examples of the presence of certain hydrolases and oxido-reductases in soft carious dentine of extracted human molar teeth.
A = Arylaminopeptidase activity in the dentinal tubules of soft carious dentin. Substrate: L-leucyl-2-naphthylamine, Fast Blue B, pH 7.0. Original magnification x48.
B = Higher magnification (x165) of arylaminopeptidase on the borderland between hard (under) and soft carious dentine (above).
C = Glocose-6-phosphate-dehyrogenase in soft carious dentine. Substrate: sodium glucose 6-phosphate, coenzyme: nitroblue tetrazolium, pH 8.0. Original magnification x48.
D = Succinate dehydrogenase in the predentine layer under a carious lesion. Substrate: sodium succinate, coenzyme: neotetrazolium, pH 7.8. Original magnification x451.
E = Lactate dehyrorogenase activity in the soft carious dentine. Substrate: sodium lactate, coenzyme: NAD, nitroblue tetrazolium, pH 8.0. Original magnification x48.
F = Higher magnification (x451) of lactate dehydrogenase activity on the borderland between hard (fractured) and soft carious dentine revealing enzyme activity in dentinal tubules, ahead microorganims.
The picture is reconstructed from the original slides published by Larmas et al. in Acta Odontol Scand 26: 127-136, 1968 (A and B) and Larmas in Arch oral Biol. 17: 1143-1153, 1972 (C - F).