Delayed Infection of Porous Polyethylene Implants After Oncologic Maxillectomy and Reconstruction: 2 Case Reports and Review of Literature

Medpor porous polyethylene implants are commonly used for facial skeletal reconstruction due to reported biocompatibility, fibrovascularization, and durability. While uncommon, late implant infections are an important consideration. We report delayed infections in 2 patients after unilateral total oncologic maxillectomy and reconstruction using Medpor implants for an ossifying fibroma and squamous cell carcinoma, respectively. In the first patient, annual interval computed tomography (CT) scans showed no recurrence of tumor or inflammatory changes. The second was lost to follow-up after adjuvant chemoradiation 1 year after resection. Patients both presented with swelling, drainage, and erythema around the implant at a mean of 4.5 years following maxillectomy. Both failed several attempts at conservative treatment. Cultures of implants removed at a mean of 2.5 months after infection grew α-hemolytic Streptococcus in the first and multiple organisms in the second, showing that the potential for delayed infection should be considered years after reconstruction.

Cranial reconstruction using prefabricated direct 3DP porous polyethylene

Purpose The purpose of this study is to evaluate the intra- and post-operative performance and safety of direct three dimensional printing (3DP) porous polyethylene implants in cranial reconstruction. Design/methodology/approach Prefabricated porous polyethylene implants were prepared by direct 3DP, and cranioplasty implantation was performed. Postoperative aesthetics, patient satisfaction, firmness of the implant, reactions to the implant and 3D computed tomography (CT) scanning were assessed after 2, 6, 12 and 24 months postoperatively. Findings No complications after surgery were encountered. Excellent aesthetic results were obtained in all cases, and all the patients were satisfied with the reconstruction outcome. Bone density structure was found to ingrowth into these direct 3DP porous polyethylene implants and the content increased with increasing follow-up times. Research limitations/implications This study was a pilot study conducted in a single group and evaluated in a short-term period. The bone formation and ingrowth were indirectly assessed by 3D CT evaluation. Originality/value This work reported the use and evaluation of direct 3DP porous polyethylene in middle- to large-sized cranial reconstructions. It evidently showed the bonding of implants to surrounding tissues which would result in the long-term stability and infection resistance of the implant.