Hirschfeld Z, Michaeli Y, Weinreb M M
J Dent Res. 1977 Jul;56(7):850-7. doi: 10.1177/00220345770560072201.
A histologic and anatomic investigation of the symphyseal region in rabbits did not reveal a bony fusion between the two halves of the mandible; these two bones are united in the anterior part by a synchrondrosis, and a definite histologic suture with interdigitating bony rugosities and interposed connective tissue, in the posterior part. Functionally, the two parts are immobile and thus constitute one bone.