Opaque dentin in relation to caries (Gottlieb, Dental Caries, 1946)

       Bernhard Gottlieb (one of the fathers of Oral Histology; former professor of the College of Dentistry at Baylor University, Texas, USA, and College of Dentistry at University of Vienna, Austria) studied dentin reactions to caries in his book “Dental Caries. Lea & Febiger, 1946” (out of print). Ground sections of carious teeth were analyzed by both transmission light microscopy and microradiography (known as Grenz rays at that time), and some sections presented opaque dentin in relation to caries:

Figure. Light microscopic (left) and microradiogarphic (right) images of the same ground section of the tooth crown showing that some areas of opaque dentin (area B in the figure on the left) are sclerotic dentin (A, B, and C areas in the figure on the right) and another area is demineralized dentin (area E in the figure on the right).

       This rare evidence is important for the understanding of the nature of caries lesions.