[Experimental study of osseointegration of nHA/BG coating and Bio-Oss in implant defects].

Purpose: To evaluate bone regeneration in defects at titanium implants with nHA/BG coating in conjunction with Bio-Oss.

Methods: Four mandibular premolars were extracted in 6 Beagle dogs. After 3 months, buccal dehiscence-type defects (2.

Enhanced osteointegration of orthopaedic implant gradient coating composed of bioactive glass and nanohydroxyapatite.

We conducted histologic and histomorphometric studies to evaluate the osteointegration of gradient coatings composed of bioactive glass and nanohydroxyapatite (BG-nHA) on titanium-alloy orthopaedic implants and surrounding bone tissue in vivo. Titanium-alloy implants with a gradient coating (gradient coating group), uncoated implants (uncoated group), and implants with a conventional hydroxyapatite (HA) coating (HA coating group) were randomly implanted in bilateral femoral condyles of 36 male New Zealand rabbits. The bone-implant contact at 12 and 24 weeks and the new bone volume in the notch created for observing bone ingrowth at 4, 12, and 24 weeks were found greater in the gradient coating group than those in both the uncoated group and the HA coating group (p < 0.

The influence of Zn on the deposition of HA on sol-gel derived bioactive glass.

To evaluate the influence of Zn on the formation of hydroxyapatite (HA), zinc-containing glass 58S4Z was prepared by substitution of CaO with 4 wt% ZnO in 58S bioactive glass, and Zn-containing simulated body fluid (ZnSBF) was prepared as soaking fluid. During the soaking, all samples could induce the deposition of HA, but 58S4Z in SBF and 58S in ZnSBF showed lower formation rate of HA than 58S in SBF, which suggests that both the Zn in glass and the Zn2+ in soaking fluid retarded the deposition of HA. The ICP and EDS analysis results indicated that the main factor was the preferential reaction of Zn2+ with PO4(3-), which resulted in a decrease of the PO4(3-) concentration in soaking fluid and the nucleation of HA.

Characterization and in vitro bioactivity of zinc-containing bioactive glass and glass-ceramics.

Zinc-containing glass is prepared by the substitution of CaO in 58S bioactive glass with 0.5 and 4 wt% ZnO, and glass-ceramics are obtained by heat-treating the glass at 1,200 C. The bending strength and in vitro bioactivity of the glass and glass-ceramics are evaluated.