Mandibular reconstruction: platelet rich plasma & scaffolds.

Abstract

Contains fulltext : 19540_mandire.pdf (publisher's version ) (Open Access)This thesis begins with a brief history of mandibular reconstruction. The use of growth factors is emphasized. The objective of this thesis is formulated: to investigate whether it is possible to perform a continuity resection of the mandibular angle and reconstruct the mandible using various scaffolds filled with an autogenous particulate cancellous bone graft taken from the iliac crest, mixed with PRP-gel. 46 goats underwent a continuity resection of the mandibular angle. Primary reconstruction was carried out using specially designed osteosynthesis plates and monocortical screws. The original cortical scaffold was used to bridge the defect, filled with an autogenous bone graft in 14 goats, whereas PRP was added in another 14 goats. In the third group of 12 goats, the cortical scaffold was irradiated before reimplantation. In another six goats the defect was bridged with a pre-shaped polylactid-acid(PDLLA) scaffold, filled with a bone graft with PRP. Radiological, histological and histomorphometric evaluation revealed that the use of PRP enhanced the bone healing considerably. In the PDLLA-group callus formation along the reconstructed segment was seen, providing bony continuity and maintaining the original contour. The particulate bone grafts within the PDLLA scaffold, however, showed considerable resorption and replacement by fibrous tissue. No plate fractures were seen and in only two goats screws turned out to be loose, without dislocation of the fragments. Because the plates are pre-shaped and heat-treated, there is less chance of metal fatigue. Chapter 6 describes the clinical application of the described techniques on eight patients who had partial mandibulectomies for malignant tumours. The histology showed bone remodelling in six cases with adequate functional and aesthetic outcome, given the poor conditions of the surrounding tissues. The presented method provides three-dimensional reconstruction with sufficient bone height and volume to facilitate prosthodontic treatment.KUN Katholieke Universiteit Nijmegen, 26 november 2004Promotores : Stoelinga, P.J.W., Jansen, J.A.188 p