Figure 2.

Selected in vivo radiographs of rats at 0-, 4-, and 8-week time points with radiodense materials having F_MP of 0%. Despite the lack of fusion as determined by manual palpation (F_MP) and histology (F_HISTO), these ceramic and activated ceramic materials have high radiodensity that mimics a fusion mass on radiography. Multifocal changes to the radiodensity pattern from 0 to 8 weeks suggest remodeling activity. Careful radiographic review is necessary to note the transverse radiolucent fissures and lack of continuous bone bridges.