This article reports a successful clinical regimen of treatment for the Class II furcation defect. Twenty-eight patients with molar teeth demonstrating Class II furcations were treated with regenerative therapy with the goal of regenerating lost interradicular periodontium. The treatment selected included scaling and root planing, surgical flap design that would enable the flap to completely cover the surgical site, complete enucleation of granulation tissue, tetracycline root conditioning, a particulate autogenous bone graft, and an expanded polytetrafluoroethylene (e-PTFE) membrane. Of the twenty-eight consecutive patients treated, twenty-five demonstrated no postoperative clinical evidence of furcation invasion, for a success rate of 89%. Eleven sites were reopened 8 to 9 months postsurgical and presented complete furcation fill with a hard, bone-like tissue. Three teeth were judged to be failures because clinical assessment revealed persistent furcation invasion. The absence of histologic evidence precludes the presumption that complete periodontal regeneration occurred.