Preclinical safety study of nacre powder in an intraosseous sheep model

Abstract

ObjectivesThe purpose of this preclinical study was to evaluate the safety, the local tissue effects and bone healing performance (osteoconduction, osseointegration) of nacre powder in a sheep intraosseous implantation model. This represents the first preclinical study to assess nacre safety and efficacy in supporting new bone formation in accordance with the ISO 10993 standard for biomedical devices.MethodsThe local tissue effects and the material performance were evaluated 8 weeks after implantation by qualitative macroscopic observation and qualitative as well as semiquantitative microscopic analyses of the bone sites. Histopathological characterisations were run to assess local tissue effects. In addition, microarchitectural, histomorphometric and histological characterisations were used to evaluate the effects of the implanted material.ResultsNacre powder was shown to cause a moderate inflammatory response in the site where it was implanted compared with the sites left empty. The biomaterial implanted within the generated defects was almost entirely degraded over the investigated time span and resulted in the formation of new bone with a seamless connection with the surrounding tissue. On the contrary, in the empty defects, the formation of a thick compact band of sclerotic bone was observed by both microarchitectural and histological characterisation.ConclusionsNacre powder was confirmed to be a safe biomaterial for bone regeneration applications in vivo, while supporting bone formation.

In Vitro Osteogenesis Study of Shell Nacre Cement with Older and Young Donor Bone Marrow Mesenchymal Stem/Stromal Cells

“…Later, Green et al demonstrated the osteogenic potential of shell nacre chips and the soluble matrix protein using human BM-MSCs [85]. Many in vivo studies have demonstrated the osteogenic potential and biocompatibility of shell nacre as a direct bone substitute [86][87][88][89][90][91][92][93][94]. Shell nacre containing hydrogel [95] and shell nacre containing calcium phosphate cement [58] showed enhanced osteogenic potential due to the addition of shell nacre.…”

Novel Bone Void Filling Cement Compositions Based on Shell Nacre and Siloxane Methacrylate Resin: Development and Characterization

“…The obtained shell nacre powder was heterogenous with particle size smaller than 0.5 µm (ImageJ analysis). In contrast, other studies have reported and used shell nacre powder of larger sizes, such as 50-100 µm [50] and 42.5 µm [51], for implantation studies.…”

“…Moreover, osteogenesis, radiopacity, osseo-integration, high fracture toughness and strength, biodegradability, anti-osteoporotic activity, and angiogenesis properties have proven shell nacre as a suitable biomaterial for hard tissue applications [45][46][47][48][49]. Although shell nacre powder has been made as a putty by mixing with autologous blood [50,51], there is no processing method to set and mould shell nacre powder into defined anatomical forms with suitable mechanical properties.…”

Scaffold Guided Bone Regeneration for the Treatment of Large Segmental Defects in Long Bones

“…Since 3D printing techniques have been tremendously improved in recent years and also allow for the processing of ceramic materials, several new structurally optimized 3D printed scaffolds have been tested in large animal models [213,[229][230][231]. Some of the recent approaches also explore the potential feasibility of novel biomaterials, such as nacre [232,233], keratin [234] or the integration of plant-derived soybean peroxidase [235].…”