Histologic Analysis of a Novel Extracellullar Matrix Membrane for Guided Bone Regeneration: An Experimental Study in Rabbits

This experiment was conducted to study the histologic feasibility and biologic impact of TiO2 impregnation of an extracellullar matrix (ECM) membrane in guided bone regeneration. Eighteen adult New Zealand White rabbits were used. Bilateral bone defects were created in edentulous areas of the maxilla. The defects were filled with demineralized freeze-dried bone (DFDB). ECM was randomly pretreated with a suspension containing saline and 3 mg TiO2 granules. A regular ECM membrane served as a control on the contralateral side. Healing periods were 2, 4, and 8 weeks. Histologic and histomorphometric analyses were performed. The parameters assessed were (1) zone of inflammatory cells adjacent to ECM membrane, (2) presence of cellullar ingrowth into ECM, and (3) presence of TiO2 particles within the ECM barrier membrane. In general, no adverse reactions toward both groups of ECM membranes could be noted. The TiO2 particles remained within the ECM after 8 weeks of healing, making histologic detection of ECM easy. Histomorphometric analysis revealed low numbers of inflammatory cells adjacent to the ECM surface and adequate preservation and integration of the barrier. Contrasting TiO2 particles impregnated into the ECM membrane can be a very useful tool for the detection of similar biologic materials in in vivo models.