Partner: S. Sefa


Ostatnie publikacje
1.Espiritu J., Sefa S., Ćwieka H., Greving I., Flenner S., Willumeit-Römer R., Seitz J.-M., Zeller-Plumhoff B., Detailing the influence of surface-treated biodegradable magnesium-based implants on the lacuno-canalicular network in sheep bone: A pilot study, Bioactive Materials, ISSN: 2452-199X, DOI: 10.2139/ssrn.4279434, pp.1-26, 2022

Streszczenie:

An increasing prevalence of bone-related injuries and aging geriatric populations continue to drive the orthopaedic implant market. A hierarchical analysis of bone remodelling after material implantation is necessary to better understand the relationship between implant and bone. Osteocytes, which are housed and communicate through the lacuno-canalicular network (LCN), are integral to bone health and remodelling processes. Therefore, it is essential to examine the framework of the LCN in response to implant materials or surface treatments.Biodegradable materials offer an alternative solution to permanent implants, which may require revision or removal surgeries. Magnesium alloys have resurfaced as promising materials due to their bone-like properties and safe degradation in vivo. To further tailor their degradation capabilities, surface treatments such as plasma electrolytic oxidation (PEO) have demonstrated to slow degradation.For the first time, the influence of a biodegradable material on the LCN is investigated by means of non-destructive 3D imaging. In this pilot study, we hypothesise noticeable variations in the LCN caused by altered chemical stimuli introduced by the PEO-coating.Utilising synchrotron-based transmission X-ray microscopy, we have characterised morphological LCN differences around uncoated and PEO-coated WE43 screws implanted into sheep bone. Bone specimens were explanted after 4, 8, and 12 weeks and regions near the implant surface were prepared for imaging. Findings from this investigation indicate that the slower degradation of PEO-coated WE43 induces healthier lacunar shapes within the LCN. However, the stimuli perceived by the uncoated material with higher degradation rates induces a greater connected LCN better prepared for bone disturbance.

Słowa kluczowe:

nanotomography, lacuno-canalicular network, Bone, magnesium, biodegradable implants

Afiliacje autorów:

Espiritu J.-other affiliation
Sefa S.-other affiliation
Ćwieka H.-IPPT PAN
Greving I.-other affiliation
Flenner S.-other affiliation
Willumeit-Römer R.-other affiliation
Seitz J.-M.-other affiliation
Zeller-Plumhoff B.-other affiliation
200p.
2.Marek R., Ćwieka H., Donouhue N., Holweg P., Moosmann J., Beckmann F., Brcic I., Schwarze U. Y., Iskhakova K., Chaabane M., Sefa S., Zeller-Plumhoff B., Weinberg A., Willumeit-Römer R., Sommer N., Degradation behavior and osseointegration of Mg-Zn-Ca screws in different bone regions of growing sheep, regenerative biomaterials, ISSN: 2056-3418, DOI: 10.1093/rb/rbac077, Vol.rbac077, pp.26-60, 2022

Streszczenie:

Magnesium (Mg)-based implants are highly attractive for the orthopedic field and may replace titanium (Ti) as support for fracture healing. To determine the implant-bone-interaction in different bony regions, we implanted Mg-based alloy ZX00 (Mg < 0.5 Zn < 0.5 Ca, in wt%) and Ti-screws into the distal epiphysis and distal metaphysis of sheep tibiae. The implant degradation and osseointegration were assessed in vivo and ex vivo after 4, 6 and 12 weeks, using a combination of clinical computed tomography (cCT), medium-resolution micro CT (µCT) and high-resolution synchrotron radiation µCT (SRµCT). Implant volume loss, gas formation, and bone growth were evaluated for both implantation sites and each bone region independently. Additionally, histological analysis of bone growth was performed on embedded hard-tissue samples. We demonstrate that in all cases, the degradation rate of ZX00-implants ranges between 0.23-0.75 mm/year. The highest degradation rates were found in the epiphysis. Bone-to-implant-contact varied between the time points and bone types for both materials. Mostly, bone-volume-to-total-volume was higher around Ti-implants. However, we found an increased cortical thickness around the ZX00-screws when compared to the Ti-screws. Our results showed the suitability of ZX00-screws for implantation into the distal meta- and epiphysis

Słowa kluczowe:

Biodegradable implants,Magnesium-based alloys,Computed tomography,Mg-Zn-Ca,Sheep,Histology

Afiliacje autorów:

Marek R.-other affiliation
Ćwieka H.-IPPT PAN
Donouhue N.-other affiliation
Holweg P.-other affiliation
Moosmann J.-other affiliation
Beckmann F.-other affiliation
Brcic I.-other affiliation
Schwarze U. Y.-other affiliation
Iskhakova K.-other affiliation
Chaabane M.-other affiliation
Sefa S.-other affiliation
Zeller-Plumhoff B.-other affiliation
Weinberg A.-other affiliation
Willumeit-Römer R.-other affiliation
Sommer N.-other affiliation
40p.