Hybrid nanocomposite scaffolds: in vitro evaluation of implant primary stability

Methods:  Thirty-two titanium implants (Winsix, Biosafin) with an innovative design were modified with three-dimensional bioactive scaffolds made up of a new hybrid ceramo-polymeric material. The biomimetic nanocomposite material was designed to promote the precipitation of hydroxyapatite nanoinclusions in periimplant bone. The scaffolds were fabricated as a foamed hydrogel covering the coronal area of the implants; the material was characterized by swelling in contact with biological fluids, with a polymerization kinetic of 0.1 mm/hour. The modified implants were inserted in freshly explanted tibiae of minipigs; 16 standard implants were used as control. Then, the tibiae were kept hydrated in physiological solution and the implants removed after 1, 6, 12 and 24 hours. An electronic device was used to measure the removal torque and the data were statistically analyzed.    

Results:  Insertion torque values ranging between 37 and 56 Ncm were recorded. Mean removal torque values of 61, 67, 79 and 86 were evidenced after 1, 6, 12 and 24 hours respectively. The ANOVA showed statistically significant differences between removal torque values (p<0.05).

Conclusions:  The novel nanocomposite hybrid ceramo-polymeric scaffolds were effective in improving implant primary stability in post-surgical early healing pahses.