Kevin, the pathology you present is not terribly uncommon and occurs in
both cattle and horses. The malformation of the tooth is the result of
damage to the dental sac. The damage might be due to trauma, i.e. the calf
was kicked in the jaw; or else due to infection. It is evident from the
greater than usual amount of swelling to the jaw that the problem was not
so much that the tooth was having trouble erupting as that there was an
infection (abscess) affecting the sac and alveolus. That could have been
due directly to trauma, but also could have been due to some kind of
low-grade, systemic and chronic infection -- the common culprits there
would be tuberculosis, or else "joint ill" due to infection of the
umbilicus at birth.

Best references to learn the details of tooth development are all
textbooks for human dental hygeinists or dentists. The general plan is
applicable to all mammals. My favorite is:

Ten-Cate, A.R. 1985. Oral Histology: Development, Structure, and Function,
2nd ed. C.V. Mosby & Co. 452 pp.

Once you've got a solid understanding of tooth formation, then move on to
studying 'bauplan' as it differs in the different taxa by reading either
of these classics:

Romer, Alfred Sherwood. 1971. The Vertebrate Body (Shorter Version). W.B.
Saunders Co., 452 pp.

Hyman, Libbie H. 1953. Comparative Vertebrate Anatomy. University of
Chicago Press, 544 pp.

There's also a third step for the person interested in cattle, horses, and
other hypsodont and sub-hypsodont species -- and that is to get a good
mental picture of what both hypsodonty and lophodonty mean -- in other
words, how you get from a bunodont, brachydont tooth to a lophodont,
hypsodont tooth. You can get this to a pretty good degree from Romer, but
IMHO some of the older authors, i.e. Henry Fairfield Osborn and his
contemporaries, had the best grasp of it: find Osborn's publications at
the American Museum of Natural History library website (they have all
their stuff available as free PDF downloads).

I go into this a little because it's a subject dear to my own heart; I am
currently writing a textbook on equine dentistry, which I have been
researching for years. I have a great admiration for all zooarchaeologists
but I also know, from talking with some anthro/archaeo graduates, that
they can be mixed up about some things. For example recently I had to
demur (for the sake of peace) in a conversation in which someone trained
in physical anthropology insisted to me that a certain human tooth
represented a 'deciduous molar'. She is confusing 'molar' in the sense of
'cheek tooth' with 'molar' in its technical sense, i.e. molar vs.
premolar. When I told her there are no deciduous molars, that only the
premolar teeth are replaced, or again that there are 'one-tooth alveoli'
vs. 'two-tooth alveoli', she was surprised and confused because she also
has muddled the term 'pre' in 'premolar', confusing 'pre' meaning anterior
in TIME with 'pre' meaning anterior in POSITION. I sympathize; it is easy
for anyone to get mixed up when the information presented in most existing
textbooks fails to convey an adequate mental picture. -- Dr. Deb


> Dear All,
>
> I have a very strange highly modified adult second molar in a cattle
> mandible from a 1st century AD deposit found at Stone Castle, near
> Dartford in Kent. I would very much like to hear if any one has any ideas
> concerning this 'modification'. It's certainly something I've never seen
> before.
>
> You can access pictures of this mandible and tooth at
> http://zooarchaeology.ning.com/photo/albums/pathology
>
> All the best
>
> Kevin Rielly
>