Skip to main content
Login | Suomeksi | På svenska | In English

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

Show full item record

Title: S53P4 bioactive glass scaffolds induce BMP expressions and integrative bone formation in a critical-sized diaphysis defect treated with a single-staged induced membrane technique
Author(s): Eriksson, Elin; Björkenheim, Robert; Strömberg, Gustav; Ainola, Mari; Uppstu, Peter; Aalto-Setälä, Laura; Leino, Vesa-Matti; Hupa, Leena; Pajarinen, Jukka; Lindfors, Nina
Contributor: University of Helsinki, Faculty of Medicine
Degree program: Degree Programme in Medicine
Specialisation: Study orientation in Swedish
Language: English
Acceptance year: 2021
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 fill- ing. 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 bioac- tive 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 his- tology, 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 os- seointegrative new bone formation throughout the scaffolds. We also demonstrated successful stable scaf- fold 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.
Kritiska diafysdefekter kompliceras av deras suboptimala läkningsförhållanden. Den kirurgiska metoden känd som den tvådelade inducerade membran-tekniken har använts för att behandla dessa utmanande defekter sedan 1980-talet. Denna metod innefattar en första operation med tillfällig implantering av en cylinder i polymetylmetakrylat för att inducera ett membran runt defekten, vilket sedan fylls med bentransplantat vid den andra operationen. En metod med en enda operation skulle minska såväl de socioekonomiska kostnaderna som patientmorbiditeten. Målet för denna studie var att möjliggöra en sådan enstegsmetod genom utveckling av ett starkt, bioaktivt implantat som ersätter både polymetylmetakrylat- cylindern och bentransplantatet. Vi konstruerade amorfa, porösa implantat av det kliniskt använda bioaktiva glaset S53P4 och utvärderade dessa in vivo i viktbärande segmentella defekter av kritisk storlek i femur på kaniner av rasen New Zealand White. S53P4-implantat och standardmässiga polymetylmetakrylat-cylindrar implanterades under 2, 4 och 8 veckor. De inducerade membranen bekräftades med histologi och deras osteostimulativa aktivitet utvärderades genom RT-qPCR-analyser av de osteostimulativa tillväxtfaktorerna BMP-2, BMP-4 och BMP-7. Benbildning och osseointegration undersöktes genom histologi, svepelektronmikroskopi, energidispersiv röntgenspektroskopi och mikro- datortomografi. Inväxten av S53P4-implantaten, defekternas läkning samt osteosyntesens integritet undersöktes manuellt samt med röntgenbildframställning. Denna studie visar att S53P4-implantaten inducerar osteostimulativa membran och producerar osseointegrerande ny benbildning. Studien demonstrerar även stabil implantatintegrering i defekten och tidiga tecken på läkning av defekten 8 veckor efter implanteringen. Denna studie presenterar viktiga överväganden för framtida forskning samt potentialen hos det bioaktiva glaset S53P4s som bensubstitut i stora diafysdefekter.
Keyword(s): S53P4 bioactive glass Scaffold for bone regeneration Bone morphogenic proteins Induced membrane Critical-sized diaphysis defect Bone substitute S53P4 bioactive glass Scaffold for bone regeneration Bone morphogenic proteins Induced membrane Critical-sized diaphysis defect Bone substitute


Files in this item

Files Size Format View
Eriksson_Elin_Avhandling_2021.pdf 13.64Mb PDF

This item appears in the following Collection(s)

Show full item record