3D Printed Silicone Meniscus Implants: Influence of the 3D Printing Process on Properties of Silicone Implants.

Eric Luis,Ram Bajpai,Wai Yee Yeong,Juha Song,Anil Kumar Bastola,Houwen Matthew Pan,Swee Leong Sing

doi:10.3390/polym12092136

Abstract

Osteoarthritis of the knee with meniscal pathologies is a severe meniscal pathology suffered by the aging population worldwide. However, conventional meniscal substitutes are not 3D-printable and lack the customizability of 3D printed implants and are not mechanically robust enough for human implantation. Similarly, 3D printed hydrogel scaffolds suffer from drawbacks of being mechanically weak and as a result patients are unable to execute immediate post-surgical weight-bearing ambulation and rehabilitation. To solve this problem, we have developed a 3D silicone meniscus implant which is (1) cytocompatible, (2) resistant to cyclic loading and mechanically similar to native meniscus, and (3) directly 3D printable. The main focus of this study is to determine whether the purity, composition, structure, dimensions and mechanical properties of silicone implants are affected by the use of a custom-made in-house 3D-printer. We have used the phosphate buffer saline (PBS) absorption test, Fourier transform infrared (FTIR) spectroscopy, surface profilometry, thermo-gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) to effectively assess and compare material properties between molded and 3D printed silicone samples.

Highlights

Ten percent of the entire global population are elderly over the age of 65 suffering from osteoarthritis of the knee with meniscal pathologies [1,2]
The first part of this section discusses the results of surface characterization of the silicone implants via light microscopy, scanning electron microscopy (SEM), phosphate buffer saline (PBS) absorption tests and surface profilometry
The second part discusses the results of X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) examining the atomic and chemical composition of the silicone implants

Summary

Introduction

Ten percent of the entire global population are elderly over the age of 65 suffering from osteoarthritis of the knee with meniscal pathologies [1,2]. CMI [4] and Actifit [5,6] are the two natural and synthetic porous meniscal implants, respectively, used for symptomatic post-meniscectomy patients, provided that there are residual peripheral meniscus and minimal cartilage damage. They suffer from the drawback of being weak mechanically and are approved for used in chronic meniscal injuries only. The utilization of additive manufacturing technologies to develop highly customizable and application-oriented prototypes or mechanical parts have gained popularity in the past two decades [7]

Methods

Results

Conclusion