Zirconia-containing radiopaque mesoporous bioactive glasses

• Radiopaque mesoporous glasses were successfully synthesized.
• The addition of ZrO2 into the network did not affect the bioactivity, resulting in a highly bioactive mesoporous glass.
• Radio-opaque mesoporous glass particles have the potential to be used as dispersed phase in composite injectable bone cements.
• The ZrO2-containing mesoporous glasses are useful for the postoperative X-ray investigation of patient׳s bone.

A radiopaque mesoporous bioactive glass (named MBGZ-7) was obtained through a combined sol–gel and evaporation induced self-assembling (EISA) route, adding zirconium propoxide to the synthesis batch as the zirconia precursor. The nitrogen sorption analysis confirmed the mesoporous nature of the glass. The assessment of in vitro bioactivity by soaking in acellular simulated body fluid (SBF) and SEM observation showed the deposition of hydroxyapatite crystals on its surface after one week. The good radiopacity level was demonstrated by comparing X-ray images of MBGZ-7 and a blank sample that did not contain radiopaque additives. It is envisaged the use of MBGZ-7 as a promising dispersed phase in composite materials for minimally invasive surgery procedures, such as injectable bone cements, in order to allow the visualization of the implant under fluoroscopic control, during both injection and follow-up.