[Biodegradable miniplates (lactosorb) in cranio-osteoplasty--experimental results with the rapidly maturing, juvenile minipig].

As a passive intracranial transmission (PIT- effect) has been described for metallic osteosyntheses materials in the infant growing skull. Thereby the use of resorbable plates and screws might be an alernative fixation device in infant craniofacial surgery. For evaluating the biological behaviour, craniotomies were performed in the frontoorbital region of four infant minipigs, six weeks of age and 6.1 kg of weight. After turning and orthotopical repositioning the full thickness bone graft were fixed with resorbable plates and screws made of LactoSorb on the left side after epiperiosteal, on the right side after subperiosteal preparation. The animals were sacrificed after 3, 6, 9 and 18 months. Histologically, a PIT- effect was detected similar to metallic microplates and screws being significant diminished after epiperiosteal preparation and plate positioning. The biodegradation was not affected by intraosseous translocation. Even in case of intrasinuidal transmission no inflammatory reactions werde observed. No contraindications for the clinical use of this specific PLLA-PGA copolymer could be found when implanted in the rapidly growing craniofacial bone surfaces.