Lateral Bone Window Closing Technique with Poly-L-Lactic Acid (PLLA) Membrane in the Augmentation of the Maxillary Sinus without Grafting Material: Evaluation of Bone Healing in a Rabbit Model.

BACKGROUND

When augmenting the maxillary sinus without grafting material, the method used to cover the bony window is a subject of debate.

PURPOSE: The purpose of this study was to evaluate the poly-L-lactic acid (PLLA) membrane as closing material of the lateral window in a maxillary sinus augmentation without bone grafting.

MATERIALS AND

METHODS

Augmentation of the maxillary sinus without grafting material and installation of titanium screws that fix the Schneiderian membrane were performed in 18 Japanese male white rabbits. The bony window was covered with a collagen membrane or PLLA membrane or no membrane. The animals were sacrificed at 4 or 8 weeks. New bone volume was calculated radiologically using microcomputed tomography (micro-CT). The samples were analyzed histologically after toluidine blue staining.

RESULTS

No significant differences were observed in the new bone volume, as measured by micro-CT. However, histomorphometric analysis demonstrated the superiority of the PLLA membrane in new bone formation compared with the collagen membrane.

CONCLUSION

The PLLA membrane is a suitable material to be applied for tissue regeneration in this animal model.