 The size of the teeth varies greatly along the length of the jaws , lending Dimetrodon its name , which means " two measures of tooth " in reference to sets of small and large teeth . One or two pairs of caniniforms ( large pointed canine @-@ like teeth ) extend from the maxilla . Large incisor teeth are also present at the tips of the upper and lower jaws , rooted in the premaxillae and dentary bones . Small teeth are present around the maxillary " step " and behind the caniniforms , becoming smaller further back in the jaw . 
