Studio sulla possibilità d'impiego di un nuovo Scaffold in Titanio per la riparazione delle gravi perdite di sostanza ossee: valutazioni preliminari

Orthopedic tissue engineering offers alternative strategies for the restoration of damaged bone tissue anatomy.Recent researches applied to the field of tissue engineering are directed to the improvement of artificial supports defined as "scaffolds". They are highly sophisticated aids, designed to facilitate attack, adhesion and cellular distension, and thus to improve deposition of new bone, which can colonize or replace the artificial implant, over time. The purpose of this study was to evaluate the healing processes of bone tissue after the implantation of a new scaffold made up of titanium, in a sheep experimental model. The evolution was evaluated firstly by means of radiographic and tomographic studies, and then through microradiographic and histological evaluations. Twoscaffoldswith differentporositywere implantedinsix sheep, belonging to Bergamasca breed, at the level ofthe righttibial. Thesescaffoldswereassociatedwith silicone stabilizedtricalcium phosphate andfibrin glue or with the adjunctionofmesenchymal stem cells(MSC). Radiographicandtomographicscanswere performed immediately after surgeryand after 9 months. Aftereuthanasia,tibiaswereexplantedforhistological and microradiographicstudies. At the first radiographic evaluation, a good positioning of the scaffold was confirmed in all subjects. At the 9 months evaluation, excellent integration of the scaffold within the bone, in absence of osteolysis, abnormal periosteal reaction and any inflammatory manifestation, was observed in all subjects. The tomographic examination showed artifacts caused by thetitanium.Microradiographic and histological studies showed excellent osteointegration and induction of new-bone formation in all subjects. The obtained results show that the biomaterial used did not produce, under the described circumstances, adverse reactions related to the component, infections or osteolysis. This study has to be considered as a preliminary one, since it included a limited number of cases. Further studies might be able to provide more reliable information concerning the use of scaffolds associated with MSC and silicone stabilizedtricalcium phosphate and the level of osteointegration of this prosthetic aid.