Findings:
There is a well-defined cystic lesion arising from the posterior right maxillary alveolus and extending into the maxillary sinus. The walls are thin and smooth and there is no spiculation or periosteal reaction present. Superiorly the lesion is centered around the crown of the impacted and displaced 18, with its roots embedded in the lateral wall of the maxillary sinus. The tooth is intact. The lesion measures 39 x 29 x 25 mm (cc by AP by transverse), essentially unchanged to the previous study. The roots of the right upper first and second molars protrude into this cystic lesion.
There is bony erosion of posterior and inferior wall of the right maxillary sinus, resulting in oroantral fistula.
Compared to the previous study there is a significant decrease in the size of the cystic lesion surrounding the crown of the horizontally impacted 28, currently measuring approximately 24 x 20 x 18 mm (CC x AP x ML), compared to 33 x 27 x 23 mm in the previous study. There is bony erosion of the inferior wall of the left maxillary sinus with consequential oroantral fistula. There is no associated odontogenic sinusitis identified.
Unchanged to the previous study a 8 x 6 mm measuring, well-defined cystic lesion is seen between the 26 and 27 teeth with cortical thinning and areas of cortical breach.
Interlamellar cell of Grunwald is noted bilaterally. Nasal septal deviation to the right with right-sided bony spur is seen.
Minimal mucosal thickening is seen in several ethmoid air cells on the left. The paranasal sinuses are otherwise clear.
The mastoid air cells on the middle ear cavities are clear.
Conclusion:
Compared to the previous study of August 2022 essentially unchanged appearance of the known dentigerous cyst surrounding the unerupted 18.
Decrease in the size of the known dentigerous cyst surrounding the unerupted 28.
No associated odontogenic sinusitis.
Stable appearance of the small cystic lesion in the left maxillary alveolar ridge between the 26 and 27, likely in keeping with a small unilocular ameloblastoma.