The premaxilla articulates with its contralateral member via the palatal process. The caudal edge of this also sutures to the maxilla. The ascending or nasal process of the premaxilla sutures to the nasal and maxilla. The bony nares are the opening of the airway in the head. They are filled with sphincter-like circular muscles that form the fleshy nostril. The palatal process of the premaxilla helps form the rostral portion of the secondary palate. This gap between the premaxillae is crossed by sutural ligaments and is a region where the ophthalmic nerve innervates the premaxillary portion of the oral cavity.