Enhanced biomaterials: systematic review of alternatives to supplement spine fusion including silicon nitride, bioactive glass, amino peptide bone graft, and tantalum

Abstract

OBJECTIVE Spinal fusions are among the most common and effective spinal surgical practices; however, the current model presents some cost and safety concerns within the patient population. Therefore, enhanced biomaterials have been presented to be an innovative yet underutilized tool to supplement the success of spinal fusion surgery. Herein, the authors discuss these biomaterials, their compositions, clinical outcomes, and cost analysis through a systematic review of the literature to date. METHODS This systematic review was conducted using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria and guidelines. Article selection was performed using the PubMed electronic bibliographic databases. The search yielded 1168 articles that were assessed and filtered for relevance by the four authors. Following the screening of titles and abstracts, 62 articles were deemed significant enough for final selection. RESULTS To date, silicon nitride, bioactive glass, amino peptide bone grafts, and tantalum are all biomaterials that could have significant roles in supporting spinal fusion. Their unique compositions allow them to be biocompatible in the spine, and their mechanisms of action stimulate osteoblast formation and support fusion success. Moreover, these biomaterials also present positive clinical and cost outcomes that support their application in spinal procedures. However, further studies with longer follow-ups are necessary to fully understand these biomaterials prior to their incorporation in mainstream spinal practice. CONCLUSIONS The combination of their positive clinical outcomes, biocompatibility, and cost-effectiveness makes these biomaterials valuable, innovative, and effective treatment modalities that could revolutionize the current model of spinal fusion.

Improvement in osteogenesis, vascularization, and corrosion resistance of titanium with silicon-nitride doped micro-arc oxidation coatings

“…Increased surface roughness reportedly promoted osteoblast spread and migration ( Jiang et al, 2013 ; Abar et al, 2021 ). In the cell viability tests, as an inorganic nanomaterial with excellent biocompatibility, Si 3 N 4 did not show significant cytotoxicity, consistent with previous reports ( Bock et al, 2015 ; Fiani et al, 2021 ; Lee et al, 2021 ). Regarding osteogenic differentiation, Si 3 N 4 doping significantly promoted ALP and mineralization compared to the control group, possibly due to the slight dissolution of Si 3 N 4 in the body fluid environment and the slow release of Si 4+ .…”

A Systematic Review and Meta-Analysis of Silicon Nitride and Biomaterial Modulus as it Relates to Subsidence Risk in Spinal Fusion Surgery

“…Recently, Fiani et al, 2021, found that Si 3 N 4 and other biomaterials can act as suitable fusion expanders given their favorable properties. [38] Significant limitations must be considered while assessing the generalizability of the results. The literature is inconsistent in its definitions of subsidence and the lack of randomized control trials remains pervasive.…”

“…The sparse data that does exist suggests that silicon nitride may afford earlier fusions and less infections from inherent bacteriostatic properties. [5] , [6] , [7] However, contradictory data also exists (i.e., SNAP trial [8] ) that alludes to the fact that Si 3 N 4 may not be superior or even comparable to PEEK, whereas another RCT by McEntire BJ et al. [9] , demonstrated non-inferiority to PEEK.…”

Determination of Sr2+ mobility in viscous bovine bone marrow by cryo‐time‐of‐flight secondary ion mass spectrometry

“…1 A promising approach is the functionalization of bone implants with bone growth-stimulating agents, such as silicon or strontium ions. [2][3][4][5][6][7][8][9][10][11] This applies in particular in the case of osteoporosis patients, who suffer from delayed fracture healing. 12 Sr 2+ has proven to be an effective therapeutic agent in the treatment of osteoporosis, mainly because of the double positive effect of Sr 2+ ions on bone metabolism: They are able to inhibit osteoclastic bone resorption and simultaneously promote new bone formation by stimulating bone-building osteoblasts.…”

“…Next‐generation biomaterials for bone fractures will be functionalized with drug release systems as well as antibiotic agents 1 . A promising approach is the functionalization of bone implants with bone growth‐stimulating agents, such as silicon or strontium ions 2–11 . This applies in particular in the case of osteoporosis patients, who suffer from delayed fracture healing 12 .…”