oa Title: The Use Of Low Intensity Pulsed Ultrasound (lipus) And Gingival Mesenchymal Stem Cells (gmscs) For The Treatment Of Severe Periodontal Defects In Dogs

Abstract: Over the past few years, tissue engineering in dentistry has achieved relevant results. Several methods have been described to enhance tissue engineering and low intensity pulsed ultrasound (LIPUS) has shown to play an important role in tissue formation and regeneration. (LIPUS) can accelerate bone fracture healing and osteogenic differentiation. The aim of this study was to evaluate the effect of local use of autologous osteogenically induced gingival stem cells (OIGSCs) and LIPUS on the healing or periodontal defects in beagle dogs. We hypothesized that the use of OIGSCs and LIPUS can enhance regeneration of periodontal defect. Eight adolescent beagle dogs were used and periodontal defects were established in their third and fourth premolars. GSCs were isolated from connective tissue of interdental papilla of each dog, characterized by flowcytometry for stem cell markers and were differentiated using osteogenic medium to produce osteogenically induced gingival cells (OIGCs). Premolars were randomly divided into 3 groups. 1) Negative control collagen only 2) OIGSCs loaded in collagen scaffold 3) and OIGSCs loaded in collagen scaffold in addition to LIPUS application. LIPUS was applied to the right side of each animal for 20 minutes using a 2.5 cm transducer. The animals were sedated prior to each LIPUS application using Isoflurane inhalation anesthesia. Clinical assessments include pocket depth (PD) and attachment level (AL) and the depths of boney defect were used to evaluate the outcome of tissue regeneration. Results: There was statistically significant difference between OIGSCs and control group (P = 0.036) and between OIGSCs+ LIPUS and control group (P= 0.023) in furcation healing. However, there was no statistically significant difference in periodontal defect healing between the OIGSCs and OIGSCs +LIPUS groups with regards to PD, AL and boney defect depth. Conclusion: OIGSCs produced furcation regeneration with or without the use of LIPUS.