Enamel hypoplasia in molars of sheep and goats and its relationship to the pattern of tooth crown growth

Horst Kierdorf, Carsten Witzel, Bethan Upex, Keith Dobney, Uwe Kierdorf

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Enamel is the most highly mineralized and durable tissue of the mammalian body. As enamel does not undergo remodeling or repair, disturbances of enamel formation leave a permanent record in the tissue that can be used for life history reconstruction. This study reports light and scanning electron microscope findings on hypoplastic enamel defects, and on the chronology of crown growth in the molars of sheep and goats. A marked reduction of enamel extension rates in cervical compared with more cuspal crown portions of sheep and goat molars was recorded, with formation of the cervical 25% of the crown taking about the same time as that of the upper 75% of the crown. This explains the more frequent occurrence of enamel hypoplasia in cervical compared with upper and middle crown portions. Regarding the identification of hypoplastic enamel defects by external inspection, our results suggest a dependence on the type of defect and the associated presence of smaller or larger amounts of coronal cementum. Defects considered to reflect a slight to moderate impairment of secretory ameloblast function can normally be correctly diagnosed as they are not occluded by thick layers of cementum. In contrast, defects denoting a severe impairment of enamel matrix secretion can typically not be correctly identified because they are occluded by large amounts of cementum, so that neither depth nor extension of the defects can be assessed on external inspection. In these cases, microscopic analysis of tooth sections is required for a correct diagnosis of the hypoplastic enamel defects.
Original languageEnglish
Pages (from-to)484-495
Number of pages12
JournalJournal of Anatomy
Volume220
Issue number5
Early online date21 Feb 2012
DOIs
Publication statusPublished - May 2012

Fingerprint

Dental Enamel Hypoplasia
Tooth Crown
enamel
goat
Dental Enamel
Crowns
Goats
sheep
tooth
Sheep
teeth
Dental Cementum
goats
defect
Growth
Ameloblasts
Chronology
Tooth
Electrons
Light

Keywords

  • hypoplastic defects
  • coronal cementum
  • crown formation
  • dental enamel
  • enamel extension rate

Cite this

Enamel hypoplasia in molars of sheep and goats and its relationship to the pattern of tooth crown growth. / Kierdorf, Horst; Witzel, Carsten; Upex, Bethan; Dobney, Keith; Kierdorf, Uwe.

In: Journal of Anatomy, Vol. 220, No. 5, 05.2012, p. 484-495.

Research output: Contribution to journalArticle

Kierdorf, Horst ; Witzel, Carsten ; Upex, Bethan ; Dobney, Keith ; Kierdorf, Uwe. / Enamel hypoplasia in molars of sheep and goats and its relationship to the pattern of tooth crown growth. In: Journal of Anatomy. 2012 ; Vol. 220, No. 5. pp. 484-495.
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