Abstract: A support post of each alveolar retractor, which is adjustably supported in a clamp means terminating each opposite end of a transverse inferior bar of a surgical mouth gag for both axial rotational and sliding movement, has a superior arcuate bar which at its medial end terminates in an upper jaw engaging member and is mounted in the upper end of said post for lateral-medial sliding adjustment to provide increased surgical exposure. Several modifications of the superior arcuate bar provide pivoting of the upper jaw engaging member to insure an optimum fit. Additional modifications of the transverse inferior bar provide mandibular engaging members which coact with the upper jaw engaging members to mount the mouth gag in operative position independently of the tongue retractor, the latter being removably mountable from the front of the transverse inferior bar without disturbing the position of the mouth gag.