Zygomatic implants require additional training and experience. Only a qualified and experienced implant dentist should perform this procedure. Some of the most common complications associated with zygomatic implants include pain and discomfort in the upper jaw, bruising and swelling around the implant and infection due to poor oral hygiene. There are risks of temporary sensory nerve deficits, orbital injury. There is also a danger that the zygomatic implant is not integrated into the zygomatic bone where it is anchored. But, the most common side-effect is chronic sinusitis.  The zygomatic implant passes from the mouth to the closed cavity of the sinuses. It brings bacteria passing from the mouth to the sinuses that results in an infection of the sinuses that can become chronic. Chronic sinusitis can be treated with antibiotics. In some cases it needs to be treated with functional endoscopic sinus surgery. The lack of osseointegration can be treated by the removal of the implant and bone grafting.