Characterization of a Bioresorbable Magnesium-Reinforced PLA-Integrated GTR/GBR Membrane as Dental Applications

Abstract

Inferior mechanical properties have always been a limitation of the bioresorbable membranes in GBR/GTR. This study is aimed at fabricating a bioresorbable magnesium-reinforced polylactic acid- (PLA-) integrated membrane and investigating its mechanical properties, degradation rate, and biocompatibility. The uncoated and fluoride-coated magnesium alloys, AZ91, were made into strips. Then, magnesium-reinforced PLA-integrated membrane was made through integration. PLA strips were used in the control group instead of magnesium strips. Specimens were cut into rectangular shape and immersed in Hank’s Balanced Salt Solution (HBSS) at 37°C for 4, 8, and 12 d. The weight loss of the AZ91 strips was measured. Three-point bending tests were conducted before and after the immersion to determine the maximum load on specimens. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) were conducted on coated and uncoated AZ91 plates to examine corrosion resistance. Murine fibroblast and osteoblast cells were cultured on circular specimens and titanium disks for 1, 3, and 5 d. Thereafter, WST test was performed to examine cell proliferation. As a result, the coated and uncoated groups showed higher maximum loads than the control group at all time points. The weight loss of AZ91 strips used in the coated group was lower than that in the uncoated group. PDP, EIS, SEM, and EDS showed that the coated AZ91 had a better corrosion resistance than the uncoated AZ91. The cell proliferation test showed that the addition of AZ91 did not have an adverse effect on osteoblast cells. Conclusively, the magnesium-reinforced PLA-integrated membrane has excellent load capacity, corrosion resistance, cell affinity, and proper degradation rate. Moreover, it has great potential as a bioresorbable membrane in the GBR/GTR application.

Advances in Modification Methods Based on Biodegradable Membranes in Guided Bone/Tissue Regeneration: A Review

“…Another modification method consists of fitting the PLA membrane with a metal material. Du et al fabricated an absorbable magnesium-enhanced PLA-integrated membrane with a coated or bare magnesium AZ91 reinforcement core [ 60 ]. The membrane showed good cell affinity, mechanical properties, corrosion resistance, and appropriate degradation rates and exhibited excellent potential for application as a bioresorbable GTR/GBR membrane.…”

“…After immersing the membrane in Hank’s Balanced Salt Solution (HbSS), among other conducted experiments, the researchers found that adding faz91 to PLA was biosafe, specifically for human use. This bioabsorbable PLA composite film can replace the traditional pure PLA film [ 60 ].…”

Preparation, physicochemical characterization, and in vitro and in vivo osteogenic evaluation of a bioresorbable, moldable, hydroxyapatite/poly(caprolactone‐co‐lactide) bone substitute

“…Balancing the rate of degradation and strength of bioresorbable materials is a critical problem for researchers who aim to expand their clinical applicability. PLA and its stereoisomers are the most widely used and researched types of aliphatic polyester materials because of their mechanical strength, modulus, and biocompatibility 19,20 . Nevertheless, drawbacks of PLA including its poor strength, limited elongation, and low heat deflection temperature limit its use as a bone substitute in clinical settings 21 .…”

ePTFE‐based biomedical devices: An overview of surgical efficiency

“…A new bioabsorbable membrane is under development with promising results 94‐97 . The first tests are only beginning to be performed and several steps must be completed before clinical trial.…”