title: Biochemical characterization of human gingival crevicular fluid during orthodontic tooth movement using Raman spectroscopy.
abstract: This study used Raman spectroscopy to report the first human gingival crevicular fluid (GCF) biochemical characterization during the early phase of orthodontic tooth movement. This technique allows for label-free and noninvasive biochemical change monitoring in GCF during orthodontic tooth movement. Ten orthodontic patients (20.8 ± 2.5 years) participated in the study. GCF samples were obtained before (baseline, 0 days) and during orthodontic treatment at 1, 7 and 28 days. For Raman spectroscopic measurement, GCF samples (5 µl) were deposited onto a gold-coated substrate, then dried at room temperature. Raman spectra GCF analysis during orthodontic treatment indicated that the hydroxyapatite to primarily collagen-dominated matrix band (phosphate 984 cm(-1)/amide I 1667 cm(-1)) intensity ratio decreased at day 7 (P < 0.05). The carbonate apatite to hydroxyapatite ratio (carbonate 1088 cm(-1)/phosphate 984 cm(-1)) was significantly higher on day 7 compared to day 0 (P < 0.05). These results indicate that demineralization occurs during the alveolar bone remodeling process. We also found notable peak shifts in the amide I range during orthodontic tooth movement. The 1658 cm(-1) in baseline red shifted to 1667 cm(-1) at orthodontic treatment day 7. Curve fitting in the amide I (1615-1725 cm(-1)) range demonstrated that increased random coil conformation was accompanied by a decrease in β-sheet structure during orthodontic tooth movement. Thus, we suggest Raman spectroscopy could be used for label-free, non-invasive GCF quality assessment during orthodontic tooth movement. Furthermore, this method may prove to be a powerful diagnostic and prognostic tool for monitoring orthodontic tooth movement in a clinical setting.
authors.affiliation: Department of Biomedical Engineering & Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, South Korea ; These authors contributed equally to this work.
authors.forename: Gyeong Bok
authors.initials: GB
authors.lastname: Jung
authors.affiliation: Department of Orthodontics, School of Dentistry, Kyung Hee University, 130-701, South Korea ; These authors contributed equally to this work.
authors.forename: Kyung-A
authors.initials: KA
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering & Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, South Korea.
authors.forename: Ihn
authors.initials: I
authors.lastname: Han
authors.affiliation: Department of Orthodontics, School of Dentistry, Kyung Hee University, 130-701, South Korea ; co-corresponding author: ygpark@khu.ac.kr.
authors.forename: Young-Guk
authors.initials: YG
authors.lastname: Park
authors.affiliation: Department of Biomedical Engineering & Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, South Korea ; Program of Medical Engineering, Kyung Hee University, Seoul 130-701, South Korea.
authors.forename: Hun-Kuk
authors.initials: HK
authors.lastname: Park
keywords: (170.0170) Medical optics and biotechnology; (170.1610) Clinical applications; (170.1850) Dentistry; (170.5660) Raman spectroscopy