Comparative study used to assess if the patient specific zirconia implant will provide better accuracy, intraoperative adaptability, precise orbital volume and soft tissue reaction with more cost effectiveness than the patient specific titanium implants in orbital floor reconstruction after blow out fractures .

Patients of both groups will be subjected to:

1. Case history including personal data, medical, surgical history and family history.
2. A full examination of the cranial and maxillofacial skeleton and soft tissue .
3. Evaluation of Visual Functions
4. Ophthalmologic consultation and clearance
5. Radiographic examination: CT scan
6. All DICOM data will be imported to the surgical planning software.

Virtual planning:

1. A midsagittal plane will be constructed then the normal orbit will be mirrored to the affected side.

2. The mirrored orbital floor will be meshed with 1.6 mm holes then its peripheries will be extended downwards by 3 mm and meshed also in order to accommodate the fixation.

3. The designed part will be subtracted then exported in Stereolithography (STL) format to be fabricated .

   The surgery will be done under General anesthesia and undertaken within 14 days to prevent fibrosis. Can be delayed 24-72 hours to allow the edema to subside before undertaking surgery.

   Intervention Group: -

   • The STL file will be milled from zirconium and then will be ready for sterilization and intraoperative fixation

   - A transconjunctival incision will be done to allow for good exposure that optimizes visualization of the orbital floor during the repair and insertion and fixation of the patient specific zirconia implant.

   Control Group: -

   • The STL file be milled from grade 4 titanium and then will be ready for sterilization and intraoperative fixation with the same surgical steps.

   Follow up:

   All patients will be examined clinically and radiographically, during postoperative 1st and 2nd week .

   Only one postoperative CT scan will be done after 2 weeks.

Inclusion Criteria:

• Patients with blow out fracture isolated and / or combined with other fracture.
• Age group: from 18 to 60 years old
• No sex predilection
• Patients with no contraindications to surgical intervention.
• Patients willing for the surgical procedure and follow-up, with an informed consent.

Exclusion Criteria :

• Medically compromised patients.
• Patients with history of previous orbital reconstruction surgery.
• Uncooperative patients.
• Patients with systemic contraindication to general anesthesia.