Dental Maxillary sinus is described as a four sided pyramid containing base, apex, roof and floor. The apex of maxillary sinus extends A Laterally into zygomatic process of maxilla B Medially into zygomatic process of maxilla C Laterally into lateral nasal wall D Superiorly into floor of orbit 💡 Explanation Maxillary sinus is described as a four sided pyramid containing base, apex, roof and floor. The apex of maxillary sinus extends ✓ Correct Answer: A. Laterally into zygomatic process of maxilla