A prospective,randomized controlled clinical study to evaluate porous β-tricalcium phosphate for lacunar bone defects repair

Objective To evaluate the clinical outcomes of a hovel porous β-tricalcium phosphate (β-TCP)and control allograft for the repair of lacunar bone defects caused by solitary bone cyst curettage.Methods From January 2003 to December 2008,the patients with solitary bone cyst were randomized into an experimental(55 cases)and a control(40 cases)group.The control group received particulate allograft bone as the graft material,and the experimental group received β-TCP.At 1 week,1,2,3,6,12,24,48months after surgery,a new radiographic scoring system was employed to calculate the biodegradation of bone graft and evaluate the influence of multiple factors.Histologic characteristic of the degradation process of β-TCP were also evaluated.Results All the cases were followed up for average 28.4 months.Radiographic semi-quantitative analysis revealed that the biodegradation effieiencies were not significantly difierent between β-TCP and allografts(P=0.424).Degradation percentage of the implanted β-TCP or allograft was higher in younger patients than those in the older ones.Degradation of β-TCP was significantly higher than that of allografts over 3 years after surgery(P=0.04).In the experimental group,β-TCP degradation was greater in the loose packing treatment than that in the dense packing treatment (P=0.03).Histological observation demonstrated that the process of new bone formation accompanied the degradation of β-TCP.Conclusion The interporous β-TCP could be an advantageous alternative to allografts for repair bone defects caused by bone cyst.The clinical application of β-TCP is safe and reliable,which shows better biodegradation and osteogenesis than allografts in long-term follow-up. Key words: Tissue engineering; Calcium phosphates; Transplatation,homologous; Bone cysts