A computer imaging technique has been advocated for measuring the volumetric fill in furcation defects. Histologic material for this investigation was obtained from an animal study using five adult baboons (Papio anubis). The photographed histology was converted into digitized electronic information, and a computer calculated the overall volume of defect fill for the treated and the untreated control sites. All volumetric measurements were expressed as a percentage of the original surgically created defect size, with 100% indicating complete healing of the defect. The results indicate that none of the defects acheived complete healing. Teeth that had received flap debridement had the most overall defect fill (79.50%). Teeth that received a biodegradable barrier (Epi-Guide) showed a mean overall defect fill of 74.98% while sites treated with ane xclusion barrier (Gore-Tex) showed 70.75% overall fill. The untreated control teeth showed a mean overall fill of 78.70%. A variety of statistical tests revealed no significant differences among teeth within the same animal and between treatments and controls. The following conclusions were drawn: (1) digital imaging technology is a useful research tool for determining the volume of defect fill in surgically created grade II molar periodontal furcation defects in the baboon model; and, (2) no significant differences were found among the treatment modalities and the untreated control sites.