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Updated: Jul 18, 2026
Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants
Published on: March 29, 2018
Qualitative effects of dioxin on molars vary among inbred mouse strains
J M Keller1, Y M Huet-Hudson, L J Leamy
1Department of Biology, University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001, USA. jmkeller@email.uncc.edu
Objective:
We evaluated the effects of different levels of the potent environmental toxicant and teratogen, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on molar development in mice in six inbred strains, all with TCDD responsive Ahr alleles.
Design:
Pregnant females were exposed on gestation day 13 to 4 different levels of TCDD (control, 0.01, 0.1 and 1.0 microg/kg) and their offspring were examined for the frequency of missing third molars (M3s) and for differences in first mandibular molar (M1) cuspal morphology.
Results:
Missing M3s were prevalent only in mice in two strains, C3H/HeJ and CBA/J, and their frequency significantly increased with increasing TCDD exposure. The frequency of the M1 variant was high in mice in only one strain, C57BL/10J, and was significantly higher in the treated compared with the control group.
Conclusions:
Inbred mice strains exhibited differential responses to TCDD suggesting that there is a genetic component, beyond Ahr differences, mediating the effects of TCDD on molar development.
