oblique ridge : the elevation in the enamel that runs obliquely across the occlusal surface of a maxillary molar ob·tun·dent : an agent or remedy that lessens or relieves pain or sensibility ob·tu·ra·tor: 1. a maxillofacial prosthesis used to close a congenital or acquired tissue opening, primarily of the hard palate and/or contiguous alveolar/soft tissue [&hellip