Intraosseous anastomosis in the maxillary sinus

During sinus-lift surgery, certain intra-osseous vessels may be accidentally cut and this cause bleeding complications in approximately 20% of osteotomies. Therefore, understanding vascular details of the maxilla is very important for the surgeon. Here, we have given an anatomical overview of maxillary sinus vascularization through anatomical dissection. We have analyzed the distribution, localization and distance from the alveolar ridge of intraosseous branches of the maxillary artery found during sinus lift surgery.

Fifty-six maxillary bone doors were made bilaterally in twenty-eight unfixed cadavers; the doors were made between the first molar and the second molar (24 doors) or between the first and the second premolar (32 doors).

Intraosseous arteries were found in 37 maxillary bones (66%). The average height of the artery from the alveolar crest was 13+/-3.2 mm in the distal doors and 18 +/- 6.1 mm in the mesial doors. Generally, the intraosseous maxillary branches ran caudo-rostrally; but in five maxillae, we found two parallel arteries, while in three cases the maxillary artery ran vertically. No differences were found between the left and right side.

The risk of vascular damage in sinus floor elevation surgery is a real problem for the oral surgeon. Detailed anatomical knowledge about sinus vascularization is very important to reduce the risk of vascular damage and bleeding. In addition the visualization of sinus anastomosis by radiology and less invasive surgery, such as piezo-surgery, could be helpful.