Patient-Specific Facial Implants in Polyetheretherketone and Their Stability: A Preliminary Study

Background Polyetheretherketone (PEEK) is a synthetic material with many favorable characteristics; PEEK implants are increasingly used for a variety of applications ranging from cranioplasty to orthopedic surgery and facial implants. Methods This study is a retrospective review of patients who underwent PEEK implant placement in our department over the last 5 years. Polyetheretherketone computer-aided design and manufacture facial implants were designed from high-resolution computed tomography (CT) scans of each patient. The implants placed were onlay implants used for facial rehabilitation purposes to correct malformative and posttraumatic malformations. Results Twenty-eight consecutive patients (11 males and 17 females) underwent PEEK implant positioning between January 2015 and December 2020. Common indications were anterior plagiocephaly, hemifacial microsomia, and residual facial imbalance after orthognathic surgery. No complications of implant breakdown, exposure, infection, or displacement were noticed during the follow-up period. During routine controls on 3 patients, we requested a craniomaxillofacial CT scan for reasons unrelated to the implanted prostheses. The CT scans were all high resolution (<1-mm slices). The CT images indicated that bone was starting to form around the implant in all 3 patients as well as in the penetrating holes that were planned in the implants. Conclusions In our experience, computer-designed, patient-specific PEEK onlay implants are a valid option for the treatment of malformative and posttraumatic malformations. This is, to the best of our knowledge, the first clinical report on bone reaction to PEEK implantation in the maxillofacial field. Moreover, based on the signs of bone regrowth that we observed in CT controls we can presume that the design of this type of prosthesis can probably take advantage of some technical stratagems not yet codified and fully exploited. Despite our preliminary favorable results, further multic