Evaluation of inflammatory processes by FTIR spectroscopy

International audienceFourier transform infrared (FTIR) spectroscopy is a powerful diagnosis technique and has been used to identify patterns of molecular changes based on vibration modes. The objective of this study was to evaluate inflammatory fibrous hyperplasia (IFH) lesions and oral normal mucosa (NM) initially with histopathological exam and then using micro-FTIR spectroscopy to analyse the samples. Eleven IFH and 11 NM samples were analysed at five different points to cover the largest area possible by the micro-FTIR technique. Bands were observed between 970 and 1743 cm−1 which corresponded to different structural components like collagen, lipids, fatty acids, proteins and amino acids. Spectral bands were more intense mostly for IFH lesions, including collagen bands, which are an important component of inflammatory fibrous hyperplasia. This study demonstrated that differentiation in the inflammatory tissue was observed in FTIR spectral differences, in terms of biochemical composition

Nanoscale hybrid implant surfaces and Osterix‐mediated osseointegration

Endosseous implant surface topography directly affects adherent cell responses following implantation. The aim of this study was to examine the impact of nanoscale topographic modification of titanium implants on Osterix gene expression since this gene has been reported as key factor for bone formation. Titanium implants with smooth and nanoscale topographies were implanted in the femurs of Osterix-Cherry mice for 1-21 days. Implant integration was evaluated using scanning electron microscopy (SEM) to evaluate cell adhesion on implant surfaces, histology, and nanotomography (NanoCT) to observe and quantify the formed bone-to-implant interface, flow cytometry to quantify of Osterix expressing cells in adjacent tissues, and real-time PCR (qPCR) to quantify the osteoinductive and osteogenic gene expression of the implant-adherent cells. SEM revealed topography-dependent adhesion of cells at early timepoints. NanoCT demonstrated greater bone formation at nanoscale implants and interfacial osteogenesis was confirmed histologically at 7 and 14 days for both smooth and nanosurface implants. Flow cytometry revealed greater numbers of Osterix positive cells in femurs implanted with nanoscale versus smooth implants. Compared to smooth surface implants, nanoscale surface adherent cells expressed higher levels of Osterix (Osx), Alkaline phosphatase (Alp), Paired related homeobox (Prx1), Dentin matrix protein 1 (Dmp1), Bone sialoprotein (Bsp), and Osteocalcin (Ocn). In conclusion, nanoscale surface implants demonstrated greater bone formation associated with higher levels of Osterix expression over the 21-day healing period with direct evidence of surface-associated gene regulation involving a nanoscale-mediated osteoinductive pathway that utilizes Osterix to direct adherent cell osteoinduction