Negative Effect of Rapidly Resorbing Properties of Bioactive Glass-Ceramics as Bone Graft Substitute in a Rabbit Lumbar Fusion Model.
- Author:
Jae Hyup LEE
1
;
Hyun Seung RYU
;
Jun Hyuk SEO
;
Do Yoon LEE
;
Bong Soon CHANG
;
Choon Ki LEE
Author Information
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords: CaO-SiO2-P2O5-B2O3 glass ceramics; Osteoconductivity; Resorption; Fusion
- MeSH: Animals; Bone Resorption; Bone Substitutes/adverse effects/*therapeutic use; Ceramics/adverse effects/*therapeutic use; Electric Conductivity; Lumbosacral Region/*surgery; Male; Rabbits; Spinal Fusion/*methods
- From:Clinics in Orthopedic Surgery 2014;6(1):87-95
- CountryRepublic of Korea
- Language:English
- Abstract: BACKGROUND: Bioactive glass-ceramics have the ability to directly bind to bones and have been widely used as bone graft substitutes due to their high osteoconductivity and biocompatibility. CaO-SiO2-P2O5-B2O3 glass-ceramics are known to have good osteoconductivity and are used as bone graft extenders. METHODS: This study aimed to evaluate the effects of the resorbing properties of glass-ceramics in bone fusion after producing and analyzing three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with high osteoconductivity that had enhanced resorption by having an increased B2O3 content. The three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with B2O3 contents of 8.0, 9.0, and 9.5 weight % were designated and grouped as P20B80, P10B90, and P5B95, respectively. Glass-ceramic types were tested for fusion rates and bone formation by employing the lumbar 5-6 intertransverse process fusion model in 51 New Zealand male rabbits. Bioactivity was assessed by soaking in simulated body fluid (SBF). RESULTS: In vitro study results showed sufficient hydroxycarbonate apatite layer formation occurred for P20B80 in1 day, for P10B90 in 3 days, and for P5B95 in 5 days after soaking in SBF. For the rabbit lumbar spine posterolateral fusion model, the autograft group recorded a 100% fusion rate with levels significantly higher than those of P20B80 (29.4%), P10B90 (0%), and P5B95 (14.3%), with high resorbing properties. Resorbing property differences among the three glass-ceramic groups were not significant. Histological results showed new bone formation confirming osteoconductivity in all three types of glass-ceramics. Radiomorphometric results also confirmed the resorbing properties of the three glass-ceramic types. CONCLUSIONS: The high resorbing properties and osteoconductivity of porous glass-ceramics can be advantageous as no glass-ceramics remain in the body. However, their relatively fast rate of resorption in the body negatively affects their role as an osteoconductive scaffold as glass-ceramics are resorbed before bony fusion.