Anterior surface of maxilla

The anterior surface of maxilla points forward and laterally, showcasing several important features. At its medial end, it curves inwards, forming the nasal notch, a concave border. This notch leads to a bony projection, which, together with its counterpart from the opposite side, creates the anterior nasal spine. Positioned just above the incisor teeth is a shallow depression known as the incisive fossa, from which the depressor septi nasi muscle originates. Near this area, at a slightly higher and more lateral position along the nasal notch, the nasalis muscle fibers begin.

Moving along the anterior surface, to the side of the canine eminence, you'll find a deeper depression called the canine fossa. It serves as the originating point for the levator anguli oris muscle fibers. Positioned just above the canine fossa is a critical opening named the infraorbital foramen. It provides a passageway for the infraorbital vessels and nerve. Situated slightly above this foramen, yet below the infraorbital margin, is where the levator labii superioris muscle starts.

The infraorbital margin is what separates the anterior surface of maxilla from the orbital surface.