Osteointegration of bioactive glass‐coated and uncoated zirconia in osteopenic bone: An in vivo experimental study

Abstract

In elderly and osteoporotic patients an age-related loss of osteoinductivity could be the biological cause of implant failure regardless of the high quality of the implanted device. yttria stabilized tetragonal zirconia (YSTZ), either coated with the bioactive glass named RKKP bioglaze (RKKP) or uncoated, was implanted in the distal femurs of sham-operated and ovariectomized female rats. Animals were sacrificed at 30 and 60 days. Histomorphometry and microhardness tests were performed to assess osteointegration rate as well as bone quality around the implants. Significant decreases (p < 0.0005) in trabecular bone volume, BV/TV (41%), trabecular bone surface BS/TV (33%), trabecular thickness Tb.Th (20%), and trabecular number Tb.N (32%), together with a significant increase in trabecular separation Tb.Sp (184%), were found for the osteopenic rats compared with the sham-operated rats. At both experimental times the RKKP coating ensured a better osteointegration rate with higher AI values than the uncoated YSTZ, even when osteopenic rats were used (48% at 30 days and 12% at 60 days). No differences were observed at the bone-biomaterial interfaces for either material when comparing sham-operated with osteopenic rats. The present results demonstrate that the RKKP bioactive glass used as a coating ensures a high osteointegration rate even in osteoporotic bone, which is already visible from postoperative day 30 and is still apparent on day 60.

Covalently‐linked hyaluronan promotes bone formation around Ti implants in a rabbit model

“…34 In particular, some authors found correlation between microhardness and variables such as volume fraction of mineral, Young's modulus, yield stress, and calcium content, bone mineralization, and collagen fiber orientation. 35 Besides the bone hardness measured in the regrown bone (HV 200 ) and that measured in the preexisting host bone (HV 1000 ), we used the percentage of their ratio (HV 200 /HV 1000 ) defined as BMI, which gives information about the possible influence of surface treatments on the process of bone maturation 35 obviously considering its preexisting host bone. In our study discrepancies between histomorphometric data and mechanical fixation were not observed, and mechanical results on implant fixation paralleled the histomorphometric data on biological osteointegration.…”

Two-piece zirconia oral implants withstand masticatory loads: An investigation in the artificial mouth

“…The focus changed from early ceramic implants made of alumina -that had to be withdrawn from the market due to high failure rates -to implants fabricated of zirconium dioxide (ZrO 2 , zirconia) ). This highly biocompatible metal oxide was reported to exhibit no cytotoxic, sensitizing, mutagenic or oncogenic effect (Covacci et al 1999, Kim et al 2000, Aldini et al 2004, Gahlert et al 2007, Gahlert et al 2009, Kohal et al 2009b, Schliephake et al 2010, Gahlert et al 2012. It is usually available as yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) having superior mechanical properties than other ceramic biomaterials owing to a phase transformation toughening mechanism (Christel et al 1989).…”

Management of atrophic maxilla in severe osteoporosis treated with bisphosphonates: a case report

“…37,38 These changes have been observed in different animal studies by a decrease of trabecular bone volume as well as bone-to-implant contact around implants. 39,40 Bone regeneration techniques such sinus augmentation and autogenous onlay bone blocks have been reported to be a predictable treatment for the management of the atrophic maxilla, however, this anatomic challenge could be even more difficult in osteoporotic patients who need implant therapy. Moreover, bone healing in osteoporotic patients taking oral BPs is unknown.…”