Custom implants are a paradigm shift in aesthetic augmentations of the midface. While there are numerous off-the-shelf augmentation options such as cheek, tear trough, and pyriform aperture (premaxillary and paranasal) implants, their effects are limited or only a subtotal midface enhancement. While this is what the vast majority of patients seek there is a subset of patients seeking a more complete or total middle third of the face projection increase.
Custom midface implants can be designed that literally push this part of the face forward in its totality. They are in some ways similar to a LeFort III advancement…minus the dentoalveolar and nose segments. By covering the entire infraorbital-malar-maxillary bony areas the midface soft tissues are pushed forward minus the lips. (whose projection is more dentoalveolar based)
Placement of custom midface implants is primarily through an intraoral approach. In some cases this may be supplemented with a lower eyelid incision as well but the reverse is never true. (primary placement through lower eyelid incisions. The intraoral approach offers the key to the custom midface implant placement which is getting it around the infraorbital nerve. The tissues must be fully released around the nerve without injury to it and the implant successfully placed around it. (if that is what the design requires)
In custom midface implants that completely cover the maxilla the infraorbital nerve location is marked by a circle but a full thickness hole in the implant is not made for it. Because of manufacturing limitations it can not be made with the nerve relief in it. That is done during surgery.
In surgery a wide hole is made in the nerve location on each side. The wider the relief the better. There is no aesthetic benefit to making a small hole and the risk of any implant compression or scarring to the nerve. Once the nerve relief is done a split in made in the upper part of the hole so the implant can be placed around the nerve.
In most custom midface implants, besides the infraorbital nerve hole, multiple perfusion holes are also placed in the implant over the maxillary surface. This allows for the overlying soft tissues to reconnect to the bone in multiple locations. This turns a large single implant pocket into multiple connected smaller ones.
The custom midface implant, often called the mask implant, provides complete coverage of the midface around the pyriform aperture centrally and the orbits superiorly. Successful placement requires navigation around the infraorbital nerve superiorly as well as a good cuff of soft tissue inferiorly for a competent closure.,
Dr. Barry Eppley
World-Renowned Plastic Surgeon