Taguchi's methods to optimize the properties and bioactivity of 3D printed polycaprolactone/mineral trioxide aggregate scaffold: Theoretical predictions and experimental validation

Abstract

Mineral trioxide aggregate (MTA) can provide bioactivity to poly‐caprolactone (PCL), which is an inert polymer used to print scaffolds. However, testing all combinations of scaffold characteristics (e.g., composition, pore size, and distribution) to optimize properties of scaffolds is time‐consuming and costly. The Taguchi's methods can identify characteristics that have major influences on the properties of complex designs, hence decreasing the number of combinations to be tested. The objective was to assess the potential of Taguchi's methods as a predictive tool for the optimization of bioactive scaffold printed using electro‐hydro dynamic jetting. A three‐level approach assessed the influence of PCL/MTA proportion, pore size, fiber dimension and number of layers in pH, degradation rate, porosity, yield strength, and Young's modulus. Data were analyzed using Tukey's honest significant difference test, analysis of mean and signal‐to‐noise ratio (S/N) test. Cytocompatibility and differentiation potential were assessed for 5 and 30 days using dental pulp stem cells and analyzed with one‐way analysis of variance (proliferation) or Mann–Whitney (qPCR). The S/N ratio and analysis of mean showed that fiber diameter and composition were the most influential characteristics in all properties. The experimental data confirmed that the addition of MTA to PCL increased the pH and scaffold degradation. Only PCL and PCL with 4% MTA allowed cell proliferation. The latter increased the genetic expression of ALP, COL‐1, OCN, and MSX‐1. The theoretical predictions were confirmed by the experiments. The Taguchi's identified the inputs that can be disregarded to optimize 3D printed meshed bioactive scaffolds.

Highly Structured 3D Electrospun Conical Scaffold: A Tool for Dental Pulp Regeneration

“…However, the structure was not porous that could result in a lack of cell infiltration, and vascularization within the scaffold could be impeded. Differently, Bhargav et al worked on very porous and structured tubes made from PCL enriched with mineral trioxide aggregates by 3D printing . Scaffold formulation, pore size and distribution, and degradation rate were well studied and optimized via Taguchi’s method to allow for sufficient DPSC proliferation.…”

A critical analysis of research methods and biological experimental models to study pulp regeneration

“…Alternatively, a 3DA aims to mimic the in vivo microarchitectures more closely, allowing for greater cell‐to‐cell contact and signalling networks (Abbott, 2003; Rosa et al, 2013). Nonetheless, the procedures used to produce 3D structures are more labourious and often demand specific skillsets and equipment (Bhargav et al, 2020; Muthusamy et al, 2021; Sriram et al, 2019). The following sections will discuss the potential uses of such technologies for the advancement of dental pulp tissue engineering and regeneration.…”

“…To overcome PCL's inertness, MTA can be incorporated into the PCL matrix (Lee et al, 2012). Indeed, the addition of 4% MTA to 3D-printed PCL scaffolds increases their degradation rate, modulus of elasticity cell proliferation rate, and the genetic expression of MSX-1, ALP, and COL-I in DPSC after 30 days (Bhargav et al, 2020). Another promising strategy is to bioprint 3D freeform cellular constructs and patient-specific tooth tissue structures.…”

Signaling Pathway and Transcriptional Regulation in Osteoblasts during Bone Healing: Direct Involvement of Hydroxyapatite as a Biomaterial

“…The Msx1 and Msx2 were upregulated during fracture repair [ 85 ]. These genes are also upregulated by several biomaterials, and used as osteoinductive markers in vitro [ 86 , 87 ].…”