[1][verification needed] It is situated within the body of the maxilla,[1][3][4] but may extend into its zygomatic and alveolar processes when large.

[citation needed] In the articulated skull this aperture is much reduced in size by the following bones: The sinus communicates through an opening into the semilunar hiatus on the lateral nasal wall.

In such cases, tooth extraction can create a fistula between the oral cavity and the sinus that nevertheless usually resolves spontaneously.

At birth, it is about 6 to 8 cm3 in volume, elongated, as is orientated in antero-posterior direction, located at the next to the medial orbital wall of the eye.

[5] After the first permanent tooth erupted at the age of six to seven, aeration of maxillary sinus is the main growth feature.

The skin over the involved sinus can be tender, hot, and even reddened due to the inflammatory process in the area.

The maxillary sinus may drain into the mouth via an abnormal opening, an oroantral fistula, a particular risk after tooth extraction.

Iatrogenic damage during dental treatment accounts for nearly half of the incidence of dental-related maxillary sinusitis.

[9] Therefore, in certain individuals the membrane +/- the bony floor of the sinus can be perforated easily, creating an opening into the mouth when a tooth is extracted.

[11] Epithelialisation happens when an OAC persist for at least 2–3 days and oral epithelial cells proliferate to line the defect.

[11] Traditionally the treatment of acute maxillary sinusitis is usually prescription of a broad-spectrum cephalosporin antibiotic resistant to beta-lactamase, administered for 10 days.

Also, surgical procedures with chronic sinus infections are now changing with the direct removal of the mucus, which is loaded with toxins from the inflammatory cells[citation needed], rather than the inflamed tissue during surgery.

If any surgery is performed, it is to enlarge the ostia in the lateral walls of the nasal cavity, creating adequate drainage.

[7] The maxillary sinus was first discovered and illustrated by Leonardo da Vinci, but the earliest attribution of significance was given to Nathaniel Highmore, the British surgeon and anatomist who described it in detail in his 1651 treatise.