Evaluation of TCP Loaded Clinoptilolite Use as Graft Material on Rabbit Tibia

Abstract

Clinoptilolite mineral which is a member of zeolite family has been recently used in medical and dental applications. Until today, it has never been used as a graft material. In the present study tricalcium phosphate (TCP) imbued 90-95% pure clinoptilolite was used as graft in rabbit tibia. General anesthesia was accomplished using intra muscular (IM) injections of Xylazin and Ketamine HCL. TCP imbued clinoptilolite was placed in the defects created in the tibias of the subjects. Control group defects were left empty. One group was sacrificed on day 28 and the other group on day 56 to evaluate osteogenesis, residual graft material, inflammation and fibrosis. Histological evaluation revealed new bone formation at 28 days to be 14/7 at control group where as its 11/7 for the experimental graft group. At 56 days the values are as 18/7 for control and 14/7 for the experimental graft groups (n = 7). Our study group is the first to perform intrabony application of clinoptilolite. No evidence of abnormal inflammatory cell formation or fibrosis was witnessed in groups. When TCP, which can be used as a standalone graft material, was mixed with zeolite it was not as effective as expected. We believe that, TCP particles are absorbed and captivated in the initial phase and due to absorption strength of zeolite cannot be released back to the environment. We assume its effect can increase with longer time periods. Bone formation without infection is observed around graft particles. Based on the present study, since clinoptilolite does not provoke an inflammatory process, its use in unison with TCP can provide a supporting structure in defects.