Evaluation of new bone formation in critical-sized rat calvarial defect using 3D printed polycaprolactone/tragacanth gum-bioactive glass composite scaffolds

Int J Biol Macromol. 2024 Jun;270(Pt 1):132361. doi: 10.1016/j.ijbiomac.2024.132361. Epub 2024 May 17.

Abstract

Critical-sized bone defects are a major challenge in reconstructive bone surgery and usually fail to be treated due to limited remaining bone quality and extensive healing time. The combination of 3D-printed scaffolds and bioactive materials is a promising approach for bone tissue regeneration. In this study, 3D-printed alkaline-treated polycaprolactone scaffolds (M-PCL) were fabricated and integrated with tragacanth gum- 45S5 bioactive glass (TG-BG) to treat critical-sized calvarial bone defects in female adult Wistar rats. After a healing period of four and eight weeks, the new bone of blank, M-PCL, and M-PCL/TG-BG groups were harvested and assessed. Micro-computed tomography, histological, biochemical, and biomechanical analyses, gene expression, and bone matrix formation were used to assess bone regeneration. The micro-computed tomography results showed that the M-PCL/TG-BG scaffolds not only induced bone tissue formation within the bone defect but also increased BMD and BV/TV compared to blank and M-PCL groups. According to the histological analysis, there was no evidence of bony union in the calvarial defect regions of blank groups, while in M-PCL/TG-BG groups bony integration and repair were observed. The M-PCL/TG-BG scaffolds promoted the Runx2 and collagen type I expression as compared with blank and M-PCL groups. Besides, the bone regeneration in M-PCL/TG-BG groups correlated with TG-BG incorporation. Moreover, the use of M-PCL/TG-BG scaffolds promoted the biomechanical properties in the bone remodeling process. These data demonstrated that the M-PCL/TG-BG scaffolds serve as a highly promising platform for the development of bone grafts, supporting bone regeneration with bone matrix formation, and osteogenic features. Our results exhibited that the 3D-printed M-PCL/TG-BG scaffolds are a promising strategy for successful bone regeneration.

Keywords: Bioglass; Bone regeneration; Polycaprolactone; Tissue engineering; Tragacanth gum.

MeSH terms

  • Animals
  • Biocompatible Materials / chemistry
  • Biocompatible Materials / pharmacology
  • Bone Regeneration* / drug effects
  • Female
  • Glass* / chemistry
  • Osteogenesis* / drug effects
  • Polyesters* / chemistry
  • Printing, Three-Dimensional*
  • Rats
  • Rats, Wistar*
  • Skull* / diagnostic imaging
  • Skull* / drug effects
  • Skull* / injuries
  • Skull* / pathology
  • Tissue Engineering / methods
  • Tissue Scaffolds* / chemistry
  • Tragacanth / chemistry
  • X-Ray Microtomography

Substances

  • Polyesters
  • polycaprolactone
  • Tragacanth
  • Biocompatible Materials