From 1974 to 1992 fifty-two patients with congenital or acquired skull defects were operated at the Department of Pediatric Surgery of the University Children's Hospital of Zurich. By 1988, in 26 patients conventional methods with PMMA (polymethyl methacrylate) plasties or rib plasties were performed. After 1988, in 26 patients skull reconstruction was done by skull splitting, application of lyophilized bone or cartilage or a combination of both. In the latter period, stabilization and fixation was always provided by biodegradable screws and bands. The results of the different techniques were compared in a retrospective fashion. PMMA plasties provided immediately full stability and good cosmetic results. Another advantage was their availability. In one patient (= 4.8%), a wound infection required the removal of the plasty. In two other patients (9.5%), an increasing mobility of the plasty could be observed during skull growth. Rib plasties were not satisfying. Skull splitting or reconstruction with lyophilized bone or cartilage showed good results with a stable integration within 3-4 months. In one patient (4%), a superficial wound infection occurred, but it did not affect the plasty. From the present study, we conclude that skull splitting or the reconstruction of skull continuity by means of lyophilized bone or cartilage with fixation through biodegradable screws and bands are the methods of first choice in children, because they are fully integrated, avoid foreign material and might have a slightly lower risk of infection. In addition, removal of the implants may be avoided.(ABSTRACT TRUNCATED AT 250 WORDS)