Quantitative morphometric evaluation of critical size experimental bone defects by microcomputed tomography.

Our aim was to show that microcomputed tomography is a useful tool for acquiring high-resolution three-dimensional tomographic images to assess bone healing, the interface with materials, and the biocompatibility of bone substitutes. Acquired images can be used for non-invasive quantitative morphometric analysis of regenerating bone, leaving the option for conventional histology to be an adjunct used at defined intervals. The temporal characterisation of the mineralisation of bone potentially has a critical role in the understanding of the dynamics of mineralisation of healing bone. This has applications both for degradable and bioactive materials and for pharmaceutical products that act on bone. Formal validation of this promising new technique will be a critical part of continuing studies.

A modified method for preparing platelet-rich plasma: an experimental study.

PURPOSE: In this study, our aim was to prepare low-cost autogenous platelet-rich plasma (PRP) for use in minor bone grafting procedures. This was the preliminary study of an experimental study concerning augmentation of bony defects with a mixture of PRP and beta-tricalcium phosphate. MATERIALS AND METHODS: Venous blood was collected from marginal ear veins of New Zealand White rabbits in EDTA (K3) vacutainer tubes. Blood samples were divided into 2 groups, and PRP was prepared through 2 methods, 1 of which is a variant of the other. The 2 PRP preparation methods described in this study were modified from Landesberg et al (J Oral Maxillofac Surg 58:297, 2000) after several trials, because the platelet enrichment percentages we obtained using their method were very low. Complete blood counts of venous blood samples, PRP, and platelet poor plasma (PPP) were made. Statistical analyses were performed using SPSS for Windows (SPSS, Chicago, IL). RESULTS: It took approximately 30 minutes to prepare PRP with both methods. Platelet counts in PRP were increased with respect to venous blood platelet counts. The differences between the experimental groups and genders were evaluated statistically with Mann-Whitney U tests (P < .05). Correlations between the groups and genders were also evaluated (P < .05). CONCLUSION: It was experimentally shown that PRP with high platelet counts can be prepared using this modified method without the need for costly autotransfusion systems.

Comparison of autogenous mucosal grafts and collagen-based, solvent-preserved allografts for vestibuloplasty.

This study was designed to determine whether solvent-preserved dura mater and fascia lata grafts would be as effective as palatal mucosal grafts for vestibuloplasty. All graft systems succeeded in covering the alveolar ridge with firmly attached tissue, which is needed to ensure prosthetic stability. There was no remarkable reduction in area until the stents were removed. However, after 6 months of vestibuloplasty, there was a significant reduction in gained vestibular area in the fascia lata group, whereas no significant difference between dura mater and palatal grafts was observed. These findings suggest that dura mater could serve as a biologic oral dressing for mucosal defects as effectively as palatal grafts in vestibuloplasty.