CLINICAL APPLICATIONS FOR ORAL BONE REGENERATION WITH MESENCHYMAL STEM CELLS FROM ADIPOSE TISSUE: WHAT ARE THE LEVELS OF SCIENTIFIC EVIDENCE?

Abstract

<h3>Background/Objective</h3> The adipose tissue-derived mesenchymal stem cells (ASCs) are considered a promising source due the capacity of pluripotent characteristics, including osteogenic properties. The aim of this critical literature review was to investigate the evidence of the clinical applicability of ASCs in order to improve bone regeneration surgeries for the treatment of clinical bone atrophy in the regions of the maxilla and mandible. <h3>Methods</h3> This literature review was prepared in accordance with the PRISMA statement and based on the proposed focused question. Specific descriptors as "mesenchymal stem cells", "bone grafting" and "cell therapy" were organized according to the PICO strategy. A literature search was performed for PubMed, Embase, Web of Science and Cochrane Library databases. <h3>Results</h3> A total of 9 potentially eligible clinical trials were included for this critical and analytical literature review. The application of ASCs was performed in maxillary surgeries (such as, maxillary sinus grafting/MSG and atrophic premaxilla/APMx) or for mandible surgery (atrophic posterior mandible/APMd). In general, regenerative surgeries were used for bone gain for posterior oral rehabilitation with dental implants. The protocols applied to obtain ASCs were performed according to the source from abdominal adipose tissue (AT) or from intra-oral buccal fat pad (BFP). The complementary findings through in vitro analysis demonstrated that AT and BFP were expressed and identified with mesenchymal surface markers for characterization of the ASCs. For MSG, when AT-ASCs were associated with alloplastic, allogeneic and/or xenogeneic grafts improved an effective and safe regenerative method. Biopsies from grafted areas showed a formation of new vital bone, demonstrating a pronounced cellular potential of ASCs. Likewise, for cases of bone regeneration for APMx or APMd, the BFP-ASCs when associated with autogenous and/or xenogeneic grafts, demonstrated a gain in bone volume through histological and radiographic analysis. <h3>Conclusions</h3> Although favorable outcomes were reported in many studies, it can be concluded that the innovative approach with ASCs when associated and applied with different grafts for bone regeneration in region of bone atrophy seems to be benefit for bone repair process. However, discussions of protocol and ethical issues must be considered in future clinical trials and effective clinical application in surgeries for oral rehabilitation.