Rapid Bone Healing Delayed by Bone Matrix Implantation

Bone induction and conduction by demineralized bone matrix (DBM) implantation can aid union in experimental bone defects of a poor healing capacity. In this study the effects of DBM in defects with highly favorable healing conditions were observed. A dividable titanium implant with a transverse bone ingrowth canal (Bone Harvest Chamber) was inserted in each rabbit tibia. Under normal conditions bone will invariably invade the bone ingrowth canal from both ends and fuse in the middle. In one chamber, a needle-like allogenous DBM implant was deposited in the canal, occupying less than 20% of its volume; another chamber in the contralateral extremity of the same animal served as control. After 14 days, the bone mass in the DBM-treated canal was diminished to 65% of that of the control, although the DBM itself was largely resorbed. This was in spite of the fact that the DBM used had inductive properties verified by its capacity to induce bone formation at an intramuscular site. The results suggest that DBM cannot be used to speed up bone healing under already favorable healing conditions, as is represented by the BHC model. Parole chiave: artificial implants, bone regeneration, osteogenesis