S53P4 bioactive glass scaffolds induce BMP expression and integrative bone formation in a critical-sized diaphysis defect treated with a single-staged induced membrane technique

Elin Eriksson*, Robert Björkenheim, Gustav Strömberg, Mari Ainola, Peter Uppstu, Laura Aalto-Setälä, Vesa-Matti Leino, Leena Hupa, Jukka Pajarinen, Nina C. Lindfors

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Critical-sized diaphysis defects are complicated by inherent sub-optimal healing conditions. The two-staged induced membrane technique has been used to treat these challenging defects since the 1980’s. It involves temporary implantation of a membrane-inducing spacer and subsequent bone graft defect filling. A single-staged, graft-independent technique would reduce both socio-economic costs and patient morbidity. Our aim was to enable such single-staged approach through development of a strong bioactive glass scaffold that could replace both the spacer and the graft filling. We constructed amorphous porous scaffolds of the clinically used bioactive glass S53P4 and evaluated them in vivo using a critical-sized defect model in the weight-bearing femur diaphysis of New Zealand White rabbits. S53P4 scaffolds and standard polymethylmethacrylate spacers were implanted for 2, 4, and 8 weeks. Induced membranes were confirmed histologically, and their osteostimulative activity was evaluated through RT-qPCR of bone morphogenic protein 2, 4, and 7 (BMPs). Bone formation and osseointegration were examined using histology, scanning electron microscopy, energy-dispersive X-ray analysis, and micro-computed tomography imaging. Scaffold integration, defect union and osteosynthesis were assessed manually and with X-ray projections. We demonstrated that S53P4 scaffolds induce osteostimulative membranes and produce osseointegrative new bone formation throughout the scaffolds. We also demonstrated successful stable scaffold integration with early defect union at 8 weeks postoperative in critical-sized segmental diaphyseal defects with implanted sintered amorphous S53P4 scaffolds. This study presents important considerations for future research and the potential of the S53P4 bioactive glass as a bone substitute in large diaphyseal defects.
Original languageEnglish
JournalActa Biomaterialia
Volume126
DOIs
Publication statusPublished - 2021
MoE publication typeA1 Journal article-refereed

Keywords

  • S53P4 bioactive glass
  • Scaffold for bone regeneration
  • Bone morphogenic proteins
  • Induced membrane
  • Critical-sized diaphysis defect
  • Bone substitute

Fingerprint

Dive into the research topics of 'S53P4 bioactive glass scaffolds induce BMP expression and integrative bone formation in a critical-sized diaphysis defect treated with a single-staged induced membrane technique'. Together they form a unique fingerprint.

Cite this