Orbital implants are medical prosthetics used to replace the eye following enucleation or evisceration procedures. These implants aid in replacing the lost eye in the orbit and allow for realistic movement of an ocular prosthesis. After orbital implantation, an ocular prosthesis, or artificial eye, is then fit over the implant to mimic the appearance of a natural eye.
Orbital implants in history have most commonly been constructed with hydroxyapatite as their main material. Original eye implant models even recruited substances such as cork, glass, and various metals. Although hydroxyapatite is well-tolerated by the body and recognized as a similar substance, the later introduction of bioceramic material has accelerated this advancement to a new level. The bioceramic orbital implant of today uses a ceramic biomaterial made of aluminum oxide (Al2O3). This material is well-known in the medical industry and has found use for more than 30 years in the orthopedic and dental fields for many types of prosthetics. Bioceramic implants became FDA-approved in April of 2000.
The body has shown to respond better to this aluminum oxide material and is therefore more biocompatible than its hydroxyapatite counterpart. Tissue grows more readily on this recent advancement, and has thus helped it to become the new standard in orbital implant material.
Noted Benefits of the Bioceramic Implant
There are three basic types of bioceramic implants: mesh wrapped, spherical, and egg-shaped. These three forms of bioceramic orbital implants have an improved vascularization structure, allowing for quick fibrovasculariation. This bioceramic material is a biocompatible, bioinert, nontoxic, and nonallergenic substance. These implants are well-known by surgeons as a stable and easily handled implant for use in enucleation and evisceration procedures. Beneficial features of these implants include:
- Porous, strong and non-brittle composition
- Rapid fibrovascularization
- No risk of disease-transmission
- Lightweight and easy to insert during surgery
- Easy to suture to extra ocular muscles
- Effortlessly hand-drilled without crumbling
- Does not release soluble components
- Does not cause excessive tissue inflammation
- Improved motility of the artificial eye
Another great benefit of this material comes in that after implanted, a protein coating is formed over the implant that camouflages the implant and prevents rejection. On the mesh-wrapped form of these implants, the vinyl mesh wrapping allows the intraocular muscles to be sutured directly to the implant, which creates a more natural movement. The porous composition of the implant allows for the previously mentioned fibrovascular ingrowth, which also helps to prevent migration of the implant over time.
One study performed to assess the effectiveness and benefits of bioceramic orbital implants showed marked benefits in the reviewed patient surgeries. One such study mapped 107 patients who received bioceramic orbital implants over a 3-year period (Jordan, D., Gillberg, S, Mawn, L. 3,2003. The Bioceramic Orbital Implant: Experience with 107 Implants Ophthalmic Plastic & Reconstructive Surgery: 19 (2):128-135). This study analyzed many of the aspects of these patients and their procedures, including, but not limited to: patient age, surgery type, implant type, complications, and treatment.
Results showed implant-related problems in only 11% of these patients, with no patients suffering from infection. Additionally, in a paper published after this study, researcher Dr. Jordan stated that these implants were also quieter than other implants. The conclusions of this study revealed that the bioceramic implant is a preferred alternative to hydroxyapatite implant. It is structurally strong, easily manufactured, and cheaper than other manufactured implants on the market. The noted complications are similar to conventional implants, but have been found to be less common.
Bioceramic orbital implants have provided ophthalmologists with easy and effective means by which to perform successful enucleation and evisceration procedures. Proven to be more biocompatible than hydroxyapatite, bioceramic orbital implants are easily inserted, non-sticky, and promote quick fibrovascularization after implantation. The improved connectivity and easy suturing to surrounding muscles helps aid in the motility of the implant while also helping to prevent implant migration. This latest generation of orbital implant is easy to manufacture, strong, and easily drillable. Its immediate protein coating after implantation relieves the concern of rejection, and the implant overall is very well tolerated by the body. It has become today’s implant of choice by ophthalmologists for use in enucleation and evisceration surgical procedures.