Effects of autologous platelet lysates on ceramic particle resorption and new bone formation in critical size defects: The role of anatomical sites

Abstract

This study investigated the effects of rabbit autologous platelet lysates (APL) on the performance of fillers consisting of calcium carbonate ceramic particles (CP) pertinent to new bone formation and repair. Critical-size defects in rabbit femurs and calvaria were filled with CP alone, CP plus APL, and CP plus APL with or without thrombin (THR). After 6 weeks, resorption of CP occurred under all conditions tested in the present study. Compared with respective CP alone controls, addition of APL resulted in significantly higher ceramic resorption, as evidenced by decreased ceramic particle diameter (p < 0.01) and number (p < 0.01) at both defect sites. The presence of THR prevented reduction of both CP diameter and number in the femoral defect sites. Addition of APL to the CP resulted in a significant (p < 0.03) decrease in new bone area at the calvarial sites, but not at the femoral sites; moreover, when THR was added to the CP plus APL fillers, bone formation in the femoral defects was significantly (p < 0.05) reduced. In addition to differences in the respective anatomical and cellular milieu, the biochemical events induced by mechanical loading at the femurs may explain the reduced ceramic particle resorption as well as the enhanced new bone formation when compared with the results obtained at the calvarial defect sites.

Variation of biomechanical properties of newly formed bone tissue determined by nanoindentation as a function of healing time

“…The procedure described by Soffer et al (2006) for non-decalcified histology was used (samples were embedded in PMMA). Nanoindentation was carried out in mature and newly formed bone tissue using a nanoindenter XP (MTS System Corp., Oak Ridge, TN, USA) with a Berkovich tip and the continuous stiffness measurement method (Oliver and Pharr 1992).…”

Bone Formation with Deproteinized Bovine Bone Mineral or Biphasic Calcium Phosphate in the Presence of Autologous Platelet Lysate: Comparative Investigation in Rabbit

“…Rabbit APL was prepared one week before surgery and stored according to previously established methods [18]. Briefly, G21 infusion sets (Ago Microperfusore, Artsana, Como, Italy) were used to obtain 10 mL blood from the intermediate branch of the caudal auricular vein from each rabbit.…”

“…Despite the attractive rationale and the in vitro observed beneficial effects of platelet concentrates [16], in vivo preclinical [17–23] and clinical [14, 24] studies, which evaluated the efficiency of particulate bone substitutes supplemented with platelet concentrates in the treatment of intrabony defects, have provided promising but not consistent results. With the exception of the biological environment of the defect, differences in key parameters that include implanted material behavior [25], mode of preparation of the platelet-concentrates, and/or individual variability [18, 26] could explain these discrepancies. In particular, most of these studies are focused on the effects of platelets concentrates in the form of PRP, a gel obtained by treating concentrated platelets with thrombin.…”

Assessment of the biomechanical properties of newly formed bone tissue using micro-Brillouin scattering

“…The rabbit was euthanized at 7 weeks post implantation and the implanted tibiae were removed and prepared for embedding in methyl methacrylate [9]. Sections (500 µm thick) were machined perpendicularly to the bone-implant interface.…”

“…Histological analyses [9] were carried out after microBrillouin measurements in order not to affect the bone biomechanical properties. The section was ground down and polished to a thickness of 100 µm (Exact Aparatebau GmbH Norderstedt, Germany) and stained with Stevenels' blue and van Gieson picro-fuschin for standard light microscopy.…”