Tooth, Incisor - Degeneration

Tooth, Incisor - Degeneration in a female Harlan Sprague-Dawley rat from a subchronic study. Odontoblast degeneration and dentin niche formation (arrows) are present.
Figure 1 of 4

Tooth, Incisor - Degeneration in a female Harlan Sprague-Dawley rat from a subchronic study (higher magnification of Figure 1). There is thinning of the dentin layer and loss of and degeneration of odontoblasts (arrow) in a dentin niche.
Figure 2 of 4

Tooth, Incisor - Degeneration in a female Harlan Sprague-Dawley rat from a subchronic study. Abnormal dentin and osteodentin production (arrow) are present.
Figure 3 of 4
comment:
Degenerative changes of the incisors are uncommon in NTP studies. Incisor degeneration comprises a set of lesions that may not all be present concurrently. Early lesions include focal mesenchymal cell vacuolation and osteodentin formation within the pulp. More severe lesions include focal or multifocal odontoblast degeneration with dentin niche formation ( Figure 1



recommendation:
Tooth, Incisor - Degeneration should be diagnosed and graded whenever present. If the dentin layer appears normal and the odontoblasts only are undergoing degeneration or necrosis, then "tooth, odontoblast - degeneration" or "tooth, odontoblast - necrosis" should be diagnosed.references:
Long PH, Herbert RA, Nyska A. 2004. Hexachlorobenzene-induced incisor degeneration in Sprague-Dawley rats. Toxicol Pathol 32:35-40. Abstract: https://www.ncbi.nlm.nih.gov/pubmed/14713546
Ten Cate AR. 1998. Dentin-pulp complex. In: Oral Histology: Development, Structure, and Function, 5th ed. Mosby-Year Book, St Louis, MO, 150-196.
Web page last updated on: November 17, 2014