beta-tricalcium phosphate [ Synthos,Cerasorb,OSferion,Synthograft,TheriLok,augment bone graft,beta-TCP,tricalcium phosphate, beta phase ] unit cells is 273 atoms compared with 312 for alpha-tricalcium phosphate; see also records for alpha-tricalcium phosphate, tricalcium phosphate; apatitic tricalcium phosphate Ca9(HPO4)(PO4)5(OH) is th