This study evaluated a bioresorbable barrier with and without decalcified freeze-dried bone allograft (DFDBA) in the treatment of human molar furcations. 14 subjects with paired class II mandibular molar furcation defects participated in the study (8 male and 6 female). The class-II furcation defects were randomly treated with either the resorbable barrier alone or resorbable barrier in combination with decalcified freeze-dried bone allograft (DFDBA). Gingival recession, probing depth, clinical attachment, and bone fill were measured 6 months post-treatment measurements were repeated and each site was surgically re-entered. When the resorbable barrier alone was compared to resorbable barrier in combination with DFDBA, probing depth reduction was significantly (p < 0.01) in favor of the combination therapy. Vertical bone gain was significant with the combination treatment demonstrating more bone fill (p < 0.02). Smoking was also a variable examined in this study. When compared to smokers, non-smokers for both treatment groups revealed greater probing depth reduction, vertical bone gain, and horizontal bone gain. Within the non-smoking group, probing depth reduction was also significantly higher for the resorbable barrier and DFDBA group than the resorbable alone group (p < 0.02). These results illustrate that the probing depth reduction is better in the non-smoker and the best in the non-smoker with the combination therapy of resorbable barrier and DFDBA than with resorbable barrier alone.