{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T00:46:26Z","timestamp":1771548386839,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,15]],"date-time":"2020-01-15T00:00:00Z","timestamp":1579046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The aim of the study was to examine the biochemical and structural changes occurring in the periodontal ligament (PDL) during orthodontic-force application using micro-Raman spectroscopy (   \u03bc   -RS). Adolescent and young patients who needed orthodontic treatment with first premolar extractions were recruited. Before extractions, orthodontic forces were applied using a closed-coil spring that was positioned between the molar and premolar. Patients were randomly divided into three groups, whose extractions were performed after 2, 7, and 14 days of force application. From the extracted premolars, PDL samples were obtained, and a fixation procedure with paraformaldehyde was adopted. Raman spectra were acquired for each PDL sample in the range of 1000\u20133200 cm      \u2212 1      and the more relevant vibrational modes of proteins (Amide I and Amide III bands) and CH     2     and CH     3     modes were shown. Analysis indicated that the protein structure in the PDL samples after different time points of orthodontic-force application was modified. In addition, changes were observed in the CH     2     and CH     3     high wavenumber region due to local hypoxia and mechanical force transduction. The reported results indicated that    \u03bc   -RS provides a valuable tool for investigating molecular interchain interactions and conformational modifications in periodontal fibers after orthodontic tooth movement, providing quantitative insight of time occurring for PDL molecular readjustment.<\/jats:p>","DOI":"10.3390\/s20020497","type":"journal-article","created":{"date-parts":[[2020,1,17]],"date-time":"2020-01-17T04:14:41Z","timestamp":1579234481000},"page":"497","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Monitoring Biochemical and Structural Changes in Human Periodontal Ligaments during Orthodontic Treatment by Means of Micro-Raman Spectroscopy"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6175-7363","authenticated-orcid":false,"given":"Letizia","family":"Perillo","sequence":"first","affiliation":[{"name":"Dipartimento Multidisciplinare di Specialit\u00e0 Medico-Chirurgiche e Odontoiatriche, Universit\u00e0 degli Studi della Campania Luigi Vanvitelli, 80138 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0291-9339","authenticated-orcid":false,"given":"Fabrizia","family":"d\u2019Apuzzo","sequence":"additional","affiliation":[{"name":"Dipartimento Multidisciplinare di Specialit\u00e0 Medico-Chirurgiche e Odontoiatriche, Universit\u00e0 degli Studi della Campania Luigi Vanvitelli, 80138 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9834-6517","authenticated-orcid":false,"given":"Maddalena","family":"Illario","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche Traslazionali, Universit\u00e0 degli Studi di Napoli Federico II, 80131 Napoli, Italy"}]},{"given":"Luigi","family":"Laino","sequence":"additional","affiliation":[{"name":"Dipartimento Multidisciplinare di Specialit\u00e0 Medico-Chirurgiche e Odontoiatriche, Universit\u00e0 degli Studi della Campania Luigi Vanvitelli, 80138 Napoli, Italy"}]},{"given":"Gaetano","family":"Di Spigna","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Mediche Traslazionali, Universit\u00e0 degli Studi di Napoli Federico II, 80131 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2743-5904","authenticated-orcid":false,"given":"Maria","family":"Lepore","sequence":"additional","affiliation":[{"name":"Dipartimento di Medicina Sperimentale, Universit\u00e0 degli Studi della Campania Luigi Vanvitelli, 80138 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6014-0588","authenticated-orcid":false,"given":"Carlo","family":"Camerlingo","sequence":"additional","affiliation":[{"name":"CNR-SPIN, Istituto Superconduttori, Materiali Innovativi e Dispositivi, 80078 Pozzuoli, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ferguson, D.J., and Wilcko, M.T. 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