but congenital absence or hypoplasia of one or more sinus cavities is not uncommon. The maxillary and ethmoidal sinuses form during the third and fourth month of gestation and are present at birth.

Endoscopic sinus surgery (ESS) is a minimally invasive ... Cone-Beam Computed Tomography (CBCT): A specialized type of X-ray equipment that provides 3D images of dental and craniofacial structures.