Human Periodontal Ligament Characterization by Means of Vibrational Spectroscopy and Electron Microscopy

Human periodontal ligament (PDL) is a membrane-like connective tissue interposed between the tooth root and the alveolar bone, the main component of which is represented by collagen fibers. During the early stage of application of orthodontic forces, different changes occur in PDL. For this reason, its characterization with conventional and non-conventional techniques can be extremely interesting. We investigated samples of PDL of orthodontic patients, aged between 13 and 21 years, using different experimental techniques. Morphological characterization of PDL samples was carried out by using a scanning electron microscope. Fourier-Transform Infrared (μ-FT-IR) and Raman (μ-RS) microspectroscopies were used for biochemical characterization of PDL samples. A biochemical characterization of PDL tissues with clear evidence of contributions from collagen, lipid and other protein was obtained. The analysis of Amide I and Amide III components was also performed, giving an indication of the protein secondary structure.