How long does a zygoma repair operation take to perform?

Depends . It really depends on what needs to be done. If you have a fractured zygoma, than likely it would take about 90 minutes to 2.5 hours. It then takes about 6 weeks to heal.
Severity dictates. It depends on the specifics of your particular fracture, but most zygomatic and maxillary fractures can be reduced and fixated with plates in 1.5 to 2 hours.