Auto-fluorescence spectra of oral submucous fibrosis.
BACKGROUND
Oral submucous fibrosis (OSF) is a chronic oral mucosal disease characterized by progressive deposition of collagen in the subepithelial connective tissue and epithelial atrophy. Previous studies have shown that at 330-nm excitation, the 380- and 460-nm emission peaks of the auto-fluorescence spectra for oral mucosal tissues reflect the collagen content in the subepithelial connective tissue and the nicotinamide adenine dinucleotide phosphate (NADH) content in the epithelial cells, respectively. Therefore, at 330-nm excitation OSF mucosa may have a higher 380-nm emission peak and a lower 460-nm emission peak than the normal oral mucosa (NOM).


METHODS
To test the above hypothesis, we measured the in vivo auto-fluorescence spectra of 59 OSF mucosal sites and compared the measured spectra with auto-fluorescence spectra obtained from 15 NOM samples from 15 healthy volunteers, five samples of friction hyperkeratosis (histologic diagnosis, hyperkeratosis and acanthosis) on OSF buccal mucosa (FHOSF), and 29 samples of oral leukoplakia (histologic diagnosis, hyperkeratosis and acanthosis) on OSF buccal mucosa (OLOSF).


RESULTS
We found that the spectrum of the OSF mucosa had a significantly higher 380-nm emission peak and a significantly lower 460-nm emission peak than the spectra of NOM, FHOSF, and OLOSF samples. When the mean (+/-SD) fluorescence intensities at 380 +/- 15 nm (I380 +/- 15 nm) and 460 +/- 15 nm (I460 +/- 15 nm) emission peaks and the mean ratio of I460 +/- 15 nm/I380 +/- 15 nm were compared between groups, we found that OSF group had a significantly higher mean value of I380 +/- 15 nm, a significantly lower mean value of I460 +/- 15 nm, and a significantly lower mean ratio of I460 +/- 15 nm/I380 +/- 15 nm than the NOM, FHOSF, and OLOSF groups (P < 0.001). However, no significant differences in the mean values of I380 +/- 15 nm, I460 +/- 15 nm, and ratio of I460 +/- 15 nm/I380 +/- 15 nm were found between NOM and FHOSF or OLOSF samples as well as between FHOSF and OLOSF samples (P > 0.05).


CONCLUSIONS
Because OSF mucosa has a very unique pattern of auto-fluorescence spectrum, we conclude that auto-fluorescence spectroscopy is a good method for real-time diagnosis of OSF.
Chen
Hsin-Ming
HM
School of Dentistry, College of Medicine, Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan.
Wang
Chih-Yu
CY
Chen
Chin-Tin
CT
Yang
Hsiang
H
Kuo
Ying-Shiung
YS
Lan
Wan-Hong
WH
Kuo
Mark Yen-Ping
MY
Chiang
Chun-Pin
CP
D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D001114:Areca / Q000009:adverse effects; D005453:Fluorescence; D006801:Humans; D008875:Middle Aged; D009061:Mouth Mucosa / Q000737:chemistry; D009914:Oral Submucous Fibrosis / Q000175:diagnosis* / Q000209:etiology; D012907:Smoking / Q000009:adverse effects; D013050:Spectrometry, Fluorescence; D018709:Statistics, Nonparametric