body size and teeth

[r.diesel@t-online.de]

With a colleague, I have been discussing the reason why predatory land mammals 
never rerached the size of the predatory sauropods. He came up with the 
interesting 
argument that the reason may be their differnet teeth, that sauropod theeth 
would be 
replaced througout life but thoose of mammals not. Is there anybody who has 
heared 
about such a theory and can help me with a literature source?
Cheers,
RDiesel