A group of researchers from Sichuan University, China, have been looking into bioprinting and bone regeneration. Bioprinting has been used in the medical field for bone regeneration, scaffold for skin graphing and making functioning organs (small test size so far). Bone regeneration has been a challenge in the medical field and in bioprinting, struggling to sustain cell growth. The team of researchers have created a scaffold with anti-bacterial properties for this study.
The team made the scaffold out of calcium phosphate powders (Ca\\P) and berberine (BBR) to create the porous scaffold. They knew from the beginning that the crucial features were:
- Composition similar to human tissue
- Stable structure like human tissue
- Suitable mechanical properties
- Ability to sustain growth and reproduction of seed cells
“3D printing technology provides a versatile strategy to fabricate complex scaffolds based on the principle of layer-by-layer accumulation,” explained the researchers. “Bone tissues have a complex porous structure, which is suitable for manufacturing with 3D printing technology.”
There are countless studies that record the success of implants, like titanium, but scientist are still trying to get around the obstacles of jaw repair and bone generation, mainly infection in the “oral environment”. The reason the team choose (Ca\\P) due to properties such as:
- Required level of biocompatibility
- Osteo-induction properties
- Ability to achieve chemical bonding with tissue
- Solubility within the human body
(BBR) has qualities that make it conductive to bone regeneration due to its antibacterial properties as well as being used to improve the immune system, blood circulation, nutrient absorption, and decrease inflammation. The team tested the scaffold for drug release properties, swelling rate characterization, and the in vitro cytotoxicity.
The team noted two stages of shrinkage 4.6% occurred during cross-linking, and 19.8% occurred during freeze-drying.
“… the mechanical and swelling test indicated the scaffolds have enough structural stability for supporting implantation,” stated the researchers.
“On the whole, with the increase of drug concentration, the drug release rate and total release amount showed a significant upward trend, indicating that the drug loading concentration was a primary factor in the regulation of release rate. When increasing the same drug concentration and varied the scaffolds pore sizes, the drug release rate was quite similar, indicating that pore size plays a secondary factor in regulating release rate,” stated the researchers.
“Both the crosslinking time and the crosslinking degree played important roles to control the drug release behavior. In vitro study indicated that the 3DP scaffolds had low cytotoxicity and it was beneficial to adhesion and proliferation of MC3T3 cells. The proposed scaffolds with both antibacterial and bone regeneration functions are promising candidates for jawbone repair.”
O’Neal, Bridget. “Improved Bioprinting for Jaw Bone Regeneration with Controlled Release, Antibacterial Properties – 3DPrint.Com: The Voice of 3D Printing / Additive Manufacturing.” 3DPrint.Com | The Voice of 3D Printing / Additive Manufacturing, 25 Feb. 2020, 3dprint.com/263579/improved-bioprinting-for-jaw-bone-regeneration-with-controlled-release-antibacterial-properties/.