Dimetrodon and Cteno Teeth

[Dinosaur World <dinoworld@msn.com>]

Does the secondary row of teeth (pterygoid?) in Dimetrodon, Ctenospondylus, 
etc. have a function? Do they show signs of wear or use?  Are they just 
vestigial appendages passed down from predecessors?

Are their pterygoids similar in any way to Mosasaurs as well?


Thanks

George