Polyetheretherketone (PEEK) Implant for the Reconstruction of Severe Destruction in the Maxilla: Case Report.

Polyetheretherketone (PEEK) implants are being increasingly used to reconstruct defects in the oral and maxillofacial region. This article reports a special case of a patient with major destruction in his maxilla due to a war injury. The resultant defect was reconstructed with a 3D-printed, patient-specific, PEEK implant, restoring acceptable function and aesthetics. The patient followed up for 13 months and showed no technical or biological complications, proving the reliability of this treatment option for recreating severe maxillofacial deformities, and benefiting from the advantage they offer, which is eliminating the need for additional surgery to harvest autogenous bone grafts. Thus, when applicable, the use of PEEK implants could be a possible alternative to other treatment modalities.

Reconstruction of defects in the oral-and-maxillofacial region presents a challenge to every clinician. Among the available reconstructive methods, regional soft tissue and bone-containing flaps, as well as free flaps with soft tissue alone or with bone, have been proposed.[1] Nonetheless, all these options need an additional surgical procedure, which is accompanied by significant morbidity in the case of major reconstructive surgeries. Besides, this kind of augmentation leads to suboptimal aesthetics in the majority of cases.

A newer technique for the treatment of oral defects was later presented, namely, the use of polyetheretherketone (PEEK) implants. These implants are designed utilizing the computer-aided design/computer-aided manufacturing (CAD/CAM) system, to fabricate a patient-specific prosthesis that restores the anatomy of the maxillofacial region and may achieve better aesthetic results than autogenous flaps/grafting materials.

This article presents a unique case of a patient who sought treatment of a major defect in the maxilla, due to a war injury. Moreover, the authors demonstrate the outcomes attained by implementing the PEEK implant and its reliability as a treatment method for large maxillofacial bony defects.

CASE REPORT

A 32-year-old male soldier presented to the oral and maxillofacial surgery clinic with a substantial maxillary defect. The patient was struck by a sniper gunshot that entered from his right zygomatic bone-side and exited from the left, leading to serious destruction in his maxilla (alveolar bone, nasal floor, and sinus walls) (Figs. 1, 2), with the opening of several oro-nasal communications. He received two surgeries to augment this defect using the iliac-crest bone; however, both ended with recipient-site infection and resorption of the graft. The reason could be the large defect area, preventing sufficient blood supply and integration of the graft.

Fig. 1.

Radiographic image showing the major destruction in the maxilla.

Fig. 2.

Clinical photograph demonstrating the severity of the defect and its effect on the facial aesthetics leading to a concave profile.

The patient underwent multislice CT examination to obtain accurate bony dimensions of the area where the implant was to be placed. A 3D model of the maxilla was reconstructed, which was used to design the PEEK implant framework of patient-specific shape and size. Finally, the design was sent to the 3D-printing laboratory (Limou Lab, Damascus, Syria) for fabrication of the PEEK reconstruction implant. (See figure, Supplemental Digital Content 1, which displays the fabricated patient-specific PEEK implant, http://links.lww.com/PRSGO/C137.)

SURGICAL PROCEDURE

Scrubbing and draping of the patient were done following the standard protocol using povidone-iodine surgical scrub.

Access to the surgical site was obtained through infraorbital and intraoral crestal incisions. The intraoral incision was accompanied by two releasing cuts at the maxillary tuberosity, to provide complete exposure to the area to be grafted. Next, the PEEK implant was installed, making sure that there was a perfect match between the edges of the implant and the bony defect, and the implant was then fixed with titanium screws (2.2 mm diameter and 16 mm length). After confirming adequate tissue release and soft tissue coverage without tension, the crestal incision was sutured in a simple interrupted fashion, securing two lines of sutures. The first line was done approximately 5 mm apical to the edge of the incision (Vicryl 4-0 thread), while the second line of sutures was performed around 1 mm apical to this edge (Silk 4-0 thread). Regarding the infraorbital incision, the muscle layer was sutured with Vicryl 4-0, and the skin layer was sutured with Prolene 4-0 thread, both layers being simple-interrupted.

Medications were prescribed as follows: Augmentin, 1 g two times a day and Bromonase Forte, 100,000 IU three times a day for 1 week. Due to the poor oral hygiene of the patient and the nature of the injury, he was kept in the hospital for 2 weeks postoperatively, during which time a strict protocol was followed, consisting of wound irrigation five times a day and regular wound cleaning with sterilized gauze. In addition, a liquid diet was implemented for the first week, followed by a soft diet for the second. At the end of this period, sutures were removed, and the patient was discharged and instructed to initiate gentle brushing with a soft brush regularly.

During the 6-month postoperative follow-up, healing was uneventful (Fig. 3). At the end of this period, exposure of four implants installed in the PEEK was done, and healing abutments were placed. After 2 weeks, an intraoral scanner was utilized to take an impression, which was used to fabricate the temporary prosthesis. Three weeks later, the final prosthesis, an acrylic bridge, was installed, and the patient was monitored for 6 months after installation (total follow-up after PEEK implant is 13 months approximately), with no complications recorded (Fig. 4). (See figure, Supplemental Digital Content 2, which displays the patient at the 6-month period after installation of the final prosthesis, demonstrating the acceptable occlusion with mandibular teeth, http://links.lww.com/PRSGO/C138.)

Fig. 3.

Radiograph showing the integration of the PEEK implant with native bone.

Fig. 4.

Photograph at the 6-month period after installation of the final prosthesis (~13 months after PEEK implant installation).

DISCUSSION

PEEK implants are suitable as bone substitutes, owing to the superior chemical resistance and similar mechanical properties to human bone. PEEK has radiographic translucency and produces no artifacts on radiographic imaging.[2] This material has been applied in orthopedic surgery[3] and in the reconstruction of maxillary and mandibular defects.[2,4,5] Nevertheless, the use of PEEK implants to restore a major deformity in the maxillofacial region (complete destruction of the maxilla) has not been documented. Therefore, the authors present this case, aiming to show the reliability of such a treatment option and the possibility of eliminating the need for additional surgery and the resultant donor site morbidity when autogenous soft and hard tissue grafts are required.[6,7] The PEEK implant method also offers the advantage of reducing the operative time.[2]

It is essential that a two-stage implant placement approach must be utilized to minimize implant exposure and ensure adequate soft tissue coverage before maturation of implant-recipient sites, keeping in mind that maxillofacial reconstruction with PEEK is limited by the availability of sufficient tissue to cover the implant. In other words, it may be necessary to import soft tissue and/or bone with vascularized free flaps if the local tissue is inadequate.

Another limitation is the short follow-up period, due to the unavailability of the patient. Long-term evaluation should be reported to determine the success of PEEK implants and their sustainability under daily functional loads, and whether complications, such as infection, oronasal communication, or implant exposure, could potentially occur.

Based on the outcome of this case and within its limitations, PEEK implants could be recommended as an alternative for the reconstruction of severe maxillofacial defects.

PATIENT CONSENT

The patient provided written consent for the use of his image.