Poly D, L-Lactide-Co-Glycolic Acid Grafting Material in Sinus Lift: In Vivo Pilot Study

The poly D,L-lactide-co-glycolic acid (PLGA) is a copolymer used in many therapeutic devices for its high rates of biodegradability and biocompatibility. The principal aim of the research was to evaluate the new bone formation, after 16 (T1) and 28 weeks (T2), in sheep maxillary sinus lift in vivo model using PLGA. Computerized tomography analysis, X-ray microanalysis, and scanning electron microscope analysis of secondary electrons (SE) and the backscattered electrons (BSE) of the samples were detected. After 28 weeks, the computed tomography analysis showed a 22% increase of UH density in the grafting areas. The X-ray microanalysis of the samples showed calcium and phosphorus increase at T1 and T2 follow-up period and the carbon and oxygen concentration decrease. The SE evaluation showed a rapid superficial resorption of the biomaterials at T1 and a completely bone reorganization of biomaterial at T2. The BSE analysis confirmed the SE data and showed the direct and intimate contact between bone and PLGA with a higher calcification in T2 compared to T1. Certainly, still other experiments and a larger number of samples will be necessary to be analyzed to determine the behavior of the PLGA in the bone regeneration; however, the PLGA used in maxillary sinus lift animal model, seem to promote new bone formation that continues increase at 28 weeks after grafting.