Dear Idoia -- What you have here is a geriatric superior M1. The
posterior-buccal corner of the enamel is broken off, which does tend to
give the tooth as a whole a wierdly sub-cylindrical appearance.
The two 'holes' in the center represent the normal anatomy of the tooth;
they are the anterior and posterior fossettes (also called infundibulae).
That their centers are eroded out to form pits is due to two factors:
first, that they probably did not completely fill when they initially
developed. The cementum that fills the fossettes is deposited by a tissue
fold containing cementoblasts that has to work in a very restricted space,
not well supplied by the circulation, so that the failure of this tissue
to fully fill the fossettes is quite common. Generally, the greatest
weakness or deficit will be right down the center.
The second factor is that the tooth is in fact geriatric, so that some of
the erosion is just due to wear. We cannot attribute it to loss due to
deposition in an acid environment of course because the other cementum or
dentine pertaining to this tooth, which would equally be vulnerable to
this kind of postmortem degradation, does not seem affected.
Horse teeth can certainly be wierd sometimes. Cheers -- Dr. Deb
> Dear zooarchers,
>
> I have found a weird looking Equus upper tooth. You can see a photo here:
> http://api.ning.com/files/C31AgRiB4u5tq8e86WvAUPZmTn1D9y4-bcJsfhp4XfI8Wl4dHfHt*SP3JIuBqxWpQ*iTZs9FIdBBvpWpf3ur1H2Gq4zavQXL/DSC_0064.JPG
>
> I apologise for the quality of the photo, but I have taken it with an old
> mobile phone. I hope it is good enough for you to see that there are two
> cavities on the occlusal surface. They do not seem to be caries to me, but
> I have no idea what might have caused this, I have never seen something
> similar. Any help or comments would be much appreciated.
>
> Thank you very much in advance and best regards to everyone!
> Idoia
>
> *Dr. Idoia Grau Sologestoa*
> Postdoctoral Fellowship funded by the Basque Government
> University of Sheffield - Department of Archaeology
> https://www.shef.ac.uk/archaeology/people/grau-sologestoa
> University of the Basque Country - Departamento de Geografía, Prehistoria
> y
> Arqueología
>
> https://sheffield.academia.edu/IdoiaGrauSologestoa
> https://www.researchgate.net/profile/Idoia_Sologestoa
> http://scholar.google.co.uk/citations?user=etZUCgQAAAAJ
>
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