Donor age and gender effects on osteoinductivity of demineralized bone matrix

Allogeneic demineralized bone matrix (DBM) has been used extensively as a clinical graft material because of its inherent osteoinductive and osteoconductive properties. There is continued debate over the acceptable age range of donors for bone and whether the effectiveness of the tissue as a graft is influenced by gender. Contradictory evidence has been obtained with DBM prepared from both animals and humans. The goal of the present investigation was to evaluate the effect of donor age and gender on the osteoinductivity of DBM prepared from human donors [male (133) and female (115) donors grouped in 10-year age brackets up to 85 years] with a statistically relevant sample size using the athymic rat ectopic bone formation model. Among males, there was a statistically significant linear association between age and osteoinductivity value (p <.001), but not among females (p =.20). The rate of change among males was 0.009 units per year. The biological relevance of such a small change in osteoinductivity is likely to be negligible, as the total variation explained by the regressions was only 8.2%. A two-way ANOVA as related to donor age (only donors < 76 years of age) and gender yielded no significant statistical association of osteoinductivity with age group, gender, and their interaction. The results confirm that properly processed demineralized bone from donors through at least 85 years of age is a viable grafting material.