Clinical Features in Patients with Delayed Exposure of Titanium Plates and Meshes after Cranioplasty.

Titanium plates and meshes are frequently used to secure bone flaps or to reconstruct defects after craniectomy. Although generally effective, they are occasionally associated with delayed skin complications. This study aimed to identify clinical features of delayed exposure of titanium implants. We retrospectively reviewed 29 patients with titanium implant exposure ≥1 year after cranioplasty or craniotomy (12 with titanium meshes and 17 with titanium plates) treated at our institution between January 2000 and December 2021. Patient characteristics (age, sex, initial disease, multiple surgeries, radiation therapy, diabetes mellitus, body mass index, and interval from the most recent surgery to implant exposure) were compared in the 2 groups. The relationship among the location of skin complications, implant placement, and original surgical incision line was also evaluated. Implant exposure was more frequent in female patients (82.8%). The median interval was significantly shorter in the mesh group than in the plate group (3.9 years vs. 12.0 years, respectively); 82.4% of plate-related exposures were located directly under previous incision, whereas mesh-related exposures tended to occur away from incisions. In both groups, more than 90% of lesions developed in areas lacking muscle coverage; 47.1% of titanium plate exposure was found over the linea temporalis and directly beneath incision lines. In conclusion, titanium implants-particularly in female patients and in those placed beneath incision lines or in areas lacking muscle coverage-are associated with an elevated risk of delayed exposure. Surgical planning should carefully consider implant positioning to reduce long-term complications.