@article{ref1,
title="Enamel changes in permanent teeth after trauma to their primary predecessors",
journal="Scandinavian journal of dental research",
year="1973",
author="Andreasen, J. O. and Ravin, J. J.",
volume="81",
number="3",
pages="203-209",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0029-845X",
doi="",
url="http://dx.doi.org/"
}