Zygomatic dental implant induced orbital fracture and inferior oblique trauma

A 51-year-old female underwent four upper zygomatic dental implants (ZI) and one upper and four lower conventional implants. Immediately postoperatively, the patient had pain and diplopia upon manual elevation of the edematous eyelid. Panoramic x-ray showed a malpositioned right upper ZI, requiring removal of the right upper ZI the following day. The patient had delayed referral to ophthalmology one month later for persistent diplopia. Computed tomography scan and magnetic resonance imaging demonstrated a right inferolateral fracture with fibrosis surrounding the inferior oblique muscle. Clinical exam showed right lower eyelid retraction, right hypotropia, and inability to elevate in adduction, consistent with a right inferior oblique paresis. Surgical exploration revealed incarceration of lid and orbital tissue into the fracture. After repositioning of the prolapsed tissue, a high-density porous polyethylene implant was placed for fracture repair. The inferior fornix was reconstructed with amniotic membrane and 5-fluorouracil was injected into the scar tissue. Six months later, the patient underwent strabismus surgery with resolution of symptoms.