Abstract

In this study, multiphoton excitation was utilized to image normal and carious dental tissues noninvasively. Unique structures in dental tissues were identified using the available multimodality (second harmonic, autofluorescence, and fluorescence lifetime analysis) without labeling. The collagen in dentin exhibits a strong second harmonic response. Both dentin and enamel emit strong autofluorescence that reveals in detail morphological features (such as dentinal tubules and enamel rods) and, despite their very similar spectral profiles, can be differentiated by lifetime analysis. Specifically, the carious dental tissue exhibits a greatly reduced autofluorescence lifetime, which result is consistent with the degree of demineralization, determined by micro-computed tomography. Our findings suggest that two-photon excited fluorescence lifetime imaging may be a promising tool for diagnosing and monitoring dental caries.

© 2010 OSA

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  1. A. R. Ten Cate, Oral Histology 3rd ed. (Mosby, St. Louis, 1998), Chap. 5.
  2. F. J. Kao, “The use of optical parametric oscillator for harmonic generation and two-photon UV fluorescence microscopy,” Microsc. Res. Tech. 63(3), 175–181 (2004).
    [CrossRef] [PubMed]
  3. S. Y. Chen, C. Y. Hsu, and C. K. Sun, “Epi-third and second harmonic generation microscopic imaging of abnormal enamel,” Opt. Express 16(15), 11670–11679 (2008).
    [PubMed]
  4. L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
    [CrossRef]
  5. A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
    [CrossRef] [PubMed]
  6. W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
    [CrossRef] [PubMed]
  7. P. J. Campagnola and L. M. Loew, “Second-harmonic imaging microscopy for visualizing biomolecular arrays in cells, tissues and organisms,” Nat. Biotechnol. 21(11), 1356–1360 (2003).
    [CrossRef] [PubMed]
  8. P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
    [CrossRef] [PubMed]
  9. M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
    [CrossRef] [PubMed]
  10. K. Koenig and H. Schneckenburger, “Laser-induced autofluorescence for medical diagnosis,” J. Fluoresc. 4(1), 17–40 (1994).
    [CrossRef]
  11. V. V. Ghukasyan and F. J. Kao, “Monitoring cellular metabolism with fluorescence lifetime of reduced nicotinamide adnine dinucleotide,” J. Phys. Chem. 113, 11532–11549 (2009).
  12. K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
    [CrossRef]
  13. R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
    [CrossRef]
  14. E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
    [CrossRef] [PubMed]
  15. R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
    [CrossRef] [PubMed]
  16. W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
    [CrossRef] [PubMed]
  17. J. R. Lakowicz, Principles of fluorescence spectroscopy, 3rd edition. (New.York: Plenum Press, 2006)
  18. V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
    [CrossRef] [PubMed]
  19. C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
    [CrossRef] [PubMed]
  20. K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
    [CrossRef] [PubMed]
  21. H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
    [CrossRef]
  22. S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
    [CrossRef]
  23. G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
    [CrossRef] [PubMed]
  24. F. Ferretti de Oliveira, A. S. Ito, and L. Bachmann, “Time-resolved fluorescence spectroscopy of white-spot caries in human enamel,” Appl. Opt. 49(12), 2244–2249 (2010).
    [CrossRef] [PubMed]
  25. C. L. Darling and D. Fried, “Real-time near IR (1310 nm) imaging of CO2 laser ablation of enamel,” Opt. Express 16(4), 2685–2693 (2008).
    [CrossRef] [PubMed]
  26. G. K. Stookey, “Quantitative light fluorescence: a technology for early monitoring of the caries process,” Dent. Clin. North Am. 49(4), 753–770, vi (2005).
    [CrossRef] [PubMed]
  27. P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
    [CrossRef] [PubMed]
  28. F. Helmchen and W. Denk, “Deep tissue two-photon microscopy,” Nat. Methods 2(12), 932–940 (2005).
    [CrossRef] [PubMed]
  29. U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
    [CrossRef] [PubMed]
  30. W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
    [CrossRef] [PubMed]
  31. K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
    [PubMed]
  32. A. Banerjee and A. Boyde, “Autofluorescence and mineral content of carious dentine: scanning optical and backscattered electron microscopic studies,” Caries Res. 32(3), 219–226 (1998).
    [CrossRef] [PubMed]
  33. W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
    [CrossRef] [PubMed]
  34. C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
    [CrossRef] [PubMed]
  35. M. V. Swain and J. Xue, “State of the art of Micro-CT applications in dental research,” Int. J. Oral Sci. 1(4), 177–188 (2009).
    [CrossRef] [PubMed]
  36. T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
    [CrossRef] [PubMed]
  37. N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
    [CrossRef] [PubMed]

2010 (1)

2009 (3)

M. V. Swain and J. Xue, “State of the art of Micro-CT applications in dental research,” Int. J. Oral Sci. 1(4), 177–188 (2009).
[CrossRef] [PubMed]

V. V. Ghukasyan and F. J. Kao, “Monitoring cellular metabolism with fluorescence lifetime of reduced nicotinamide adnine dinucleotide,” J. Phys. Chem. 113, 11532–11549 (2009).

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

2008 (2)

2007 (4)

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

2006 (2)

E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
[CrossRef] [PubMed]

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

2005 (5)

N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
[CrossRef] [PubMed]

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

F. Helmchen and W. Denk, “Deep tissue two-photon microscopy,” Nat. Methods 2(12), 932–940 (2005).
[CrossRef] [PubMed]

G. K. Stookey, “Quantitative light fluorescence: a technology for early monitoring of the caries process,” Dent. Clin. North Am. 49(4), 753–770, vi (2005).
[CrossRef] [PubMed]

2004 (2)

F. J. Kao, “The use of optical parametric oscillator for harmonic generation and two-photon UV fluorescence microscopy,” Microsc. Res. Tech. 63(3), 175–181 (2004).
[CrossRef] [PubMed]

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

2003 (3)

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

P. J. Campagnola and L. M. Loew, “Second-harmonic imaging microscopy for visualizing biomolecular arrays in cells, tissues and organisms,” Nat. Biotechnol. 21(11), 1356–1360 (2003).
[CrossRef] [PubMed]

2002 (4)

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
[CrossRef] [PubMed]

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

2001 (1)

R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
[CrossRef]

2000 (2)

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

1999 (1)

K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
[PubMed]

1998 (1)

A. Banerjee and A. Boyde, “Autofluorescence and mineral content of carious dentine: scanning optical and backscattered electron microscopic studies,” Caries Res. 32(3), 219–226 (1998).
[CrossRef] [PubMed]

1997 (1)

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

1994 (1)

K. Koenig and H. Schneckenburger, “Laser-induced autofluorescence for medical diagnosis,” J. Fluoresc. 4(1), 17–40 (1994).
[CrossRef]

1993 (1)

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

1991 (1)

U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
[CrossRef] [PubMed]

Ameer-Beg, S. M.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Avramov, L.

E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
[CrossRef] [PubMed]

Bachmann, L.

F. Ferretti de Oliveira, A. S. Ito, and L. Bachmann, “Time-resolved fluorescence spectroscopy of white-spot caries in human enamel,” Appl. Opt. 49(12), 2244–2249 (2010).
[CrossRef] [PubMed]

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Balooch, M.

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

Banerjee, A.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

A. Banerjee and A. Boyde, “Autofluorescence and mineral content of carious dentine: scanning optical and backscattered electron microscopic studies,” Caries Res. 32(3), 219–226 (1998).
[CrossRef] [PubMed]

Barber, P. R.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Barry, N. P.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

Becker, W.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

Behne, M. J.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

Benndorf, K.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

Bergmann, A.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

Berland, K. M.

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

Biskup, C.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

Booth, M.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Borisova, E.

E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
[CrossRef] [PubMed]

Boyde, A.

A. Banerjee and A. Boyde, “Autofluorescence and mineral content of carious dentine: scanning optical and backscattered electron microscopic studies,” Caries Res. 32(3), 219–226 (1998).
[CrossRef] [PubMed]

Brookes, S. J.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Buchalla, W.

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

Campagnola, P. J.

P. J. Campagnola and L. M. Loew, “Second-harmonic imaging microscopy for visualizing biomolecular arrays in cells, tissues and organisms,” Nat. Biotechnol. 21(11), 1356–1360 (2003).
[CrossRef] [PubMed]

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Chen, M. H.

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

Chen, S. Y.

Chen, W. L.

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

Christie, R.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Clegg, R. M.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

Cook, R. J.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

da Costa Ribeiro, A.

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Darendeliler, M. A.

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

Darling, C. L.

Demos, S. G.

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

Denk, W.

F. Helmchen and W. Denk, “Deep tissue two-photon microscopy,” Nat. Methods 2(12), 932–940 (2005).
[CrossRef] [PubMed]

Dong, C. Y.

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

Dosche, C.

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

Draaijer, A.

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

Efeoglu, C.

N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
[CrossRef] [PubMed]

Efeoglu, N.

N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
[CrossRef] [PubMed]

Elson, D. S.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Ferretti de Oliveira, F.

Flemming, G.

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

French, P. M. W.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Fried, D.

Fwu, P. T.

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

Gallagher, R. R.

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

Gerritsen, H. C.

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

Ghukasyan, V. V.

V. V. Ghukasyan and F. J. Kao, “Monitoring cellular metabolism with fluorescence lifetime of reduced nicotinamide adnine dinucleotide,” J. Phys. Chem. 113, 11532–11549 (2009).

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

Girkin, J. M.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Gomes, L.

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Gratton, E.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

Hafström-Björkman, U.

U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
[CrossRef] [PubMed]

Hanson, K. M.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

He, L. H.

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

Helmchen, F.

F. Helmchen and W. Denk, “Deep tissue two-photon microscopy,” Nat. Methods 2(12), 932–940 (2005).
[CrossRef] [PubMed]

Hibst, R.

R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
[CrossRef]

K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
[PubMed]

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

Hille, C.

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

Hink, M. A.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

Hoppe, P. E.

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Hsu, C. Y.

Hsu, Y. Y.

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

Huang, T. T.

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

Hyman, B. T.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Ince, C.

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

Ito, A. S.

F. Ferretti de Oliveira, A. S. Ito, and L. Bachmann, “Time-resolved fluorescence spectroscopy of white-spot caries in human enamel,” Appl. Opt. 49(12), 2244–2249 (2010).
[CrossRef] [PubMed]

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Jones, A. S.

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

Juskaitis, R.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Kao, F. J.

V. V. Ghukasyan and F. J. Kao, “Monitoring cellular metabolism with fluorescence lifetime of reduced nicotinamide adnine dinucleotide,” J. Phys. Chem. 113, 11532–11549 (2009).

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

F. J. Kao, “The use of optical parametric oscillator for harmonic generation and two-photon UV fluorescence microscopy,” Microsc. Res. Tech. 63(3), 175–181 (2004).
[CrossRef] [PubMed]

Kirkham, J.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Koenig, K.

K. Koenig and H. Schneckenburger, “Laser-induced autofluorescence for medical diagnosis,” J. Fluoresc. 4(1), 17–40 (1994).
[CrossRef]

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

König, K.

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
[PubMed]

Kung, S. H.

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

Lahn, M.

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

Leveque-Fort, S.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Lever, M. J.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Levine, Y. K.

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

Loew, L. M.

P. J. Campagnola and L. M. Loew, “Second-harmonic imaging microscopy for visualizing biomolecular arrays in cells, tissues and organisms,” Nat. Biotechnol. 21(11), 1356–1360 (2003).
[CrossRef] [PubMed]

Löhmannsröben, H.-G.

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

Lussi, A.

R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
[CrossRef]

Malone, C. J.

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Marshall, G. W.

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

Marshall, S. J.

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

Masters, B. R.

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

Mauro, T. M.

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

McConnell, G.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Millard, A. C.

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Mohler, W. A.

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Neil, M. A. A.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Ng, T.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Nikitin, A. Y.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Paulus, R.

R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
[CrossRef]

Robinson, C.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Sanders, R.

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

Schneckenburger, H.

K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
[PubMed]

K. Koenig and H. Schneckenburger, “Laser-induced autofluorescence for medical diagnosis,” J. Fluoresc. 4(1), 17–40 (1994).
[CrossRef]

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

Shore, R. C.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Siegel, J.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

So, P. T. C.

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

Stookey, G. K.

G. K. Stookey, “Quantitative light fluorescence: a technology for early monitoring of the caries process,” Dent. Clin. North Am. 49(4), 753–770, vi (2005).
[CrossRef] [PubMed]

Strafford, S.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Sucharov, L. O.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Sun, C. K.

Sun, Y.

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

Sundström, F.

U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
[CrossRef] [PubMed]

Swain, M. V.

M. V. Swain and J. Xue, “State of the art of Micro-CT applications in dental research,” Int. J. Oral Sci. 1(4), 177–188 (2009).
[CrossRef] [PubMed]

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

ten Bosch, J. J.

U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
[CrossRef] [PubMed]

Terasaki, M.

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

Tromberg, B. J.

A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
[CrossRef] [PubMed]

Uzunov, T.

E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
[CrossRef] [PubMed]

Vojnovic, B.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Watson, T.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Watson, T. F.

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

Webb, S. E. D.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Webb, W. W.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Williams, R. M.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Wilson, T.

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

Wood, D.

N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
[CrossRef] [PubMed]

Wood, S. R.

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Xue, J.

M. V. Swain and J. Xue, “State of the art of Micro-CT applications in dental research,” Int. J. Oral Sci. 1(4), 177–188 (2009).
[CrossRef] [PubMed]

Yeh, A.

A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
[CrossRef] [PubMed]

Zezell, D. M.

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Zipfel, W. R.

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Zoumi, A.

A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
[CrossRef] [PubMed]

Acta Odontol. Scand. (1)

U. Hafström-Björkman, F. Sundström, and J. J. ten Bosch, “Fluorescence in dissolved fractions of human enamel,” Acta Odontol. Scand. 49(3), 133–138 (1991).
[CrossRef] [PubMed]

Annu. Rev. Biomed. Eng. (1)

P. T. C. So, C. Y. Dong, B. R. Masters, and K. M. Berland, “Two-photon excitation fluorescence microscopy,” Annu. Rev. Biomed. Eng. 2(1), 399–429 (2000).
[CrossRef] [PubMed]

Appl. Opt. (1)

Appl. Spectrosc. Rev. (1)

L. Bachmann, D. M. Zezell, A. da Costa Ribeiro, L. Gomes, and A. S. Ito, “Fluorescence spectroscopy of biological tissue-A review,” Appl. Spectrosc. Rev. 41(6), 575–590 (2006).
[CrossRef]

Biophys. J. (2)

P. J. Campagnola, A. C. Millard, M. Terasaki, P. E. Hoppe, C. J. Malone, and W. A. Mohler, “Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues,” Biophys. J. 82(1), 493–508 (2002).
[CrossRef] [PubMed]

K. M. Hanson, M. J. Behne, N. P. Barry, T. M. Mauro, E. Gratton, and R. M. Clegg, “Two-photon fluorescence lifetime imaging of the skin stratum corneum pH gradient,” Biophys. J. 83(3), 1682–1690 (2002).
[CrossRef] [PubMed]

Caries Res. (3)

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

A. Banerjee and A. Boyde, “Autofluorescence and mineral content of carious dentine: scanning optical and backscattered electron microscopic studies,” Caries Res. 32(3), 219–226 (1998).
[CrossRef] [PubMed]

W. Buchalla, “Comparative fluorescence spectroscopy shows differences in noncavitated enamel lesions,” Caries Res. 39(2), 150–156 (2005).
[CrossRef] [PubMed]

Cell. Mol. Biol. (Noisy-le-grand) (1)

K. König, H. Schneckenburger, and R. Hibst, “Time-gated in vivo autofluorescence imaging of dental caries,” Cell. Mol. Biol. (Noisy-le-grand) 45(2), 233–239 (1999).
[PubMed]

Crit. Rev. Oral Biol. Med. (1)

C. Robinson, R. C. Shore, S. J. Brookes, S. Strafford, S. R. Wood, and J. Kirkham, “The chemistry of enamel caries,” Crit. Rev. Oral Biol. Med. 11(4), 481–495 (2000).
[CrossRef] [PubMed]

Dent. Clin. North Am. (1)

G. K. Stookey, “Quantitative light fluorescence: a technology for early monitoring of the caries process,” Dent. Clin. North Am. 49(4), 753–770, vi (2005).
[CrossRef] [PubMed]

Int. J. Oral Sci. (1)

M. V. Swain and J. Xue, “State of the art of Micro-CT applications in dental research,” Int. J. Oral Sci. 1(4), 177–188 (2009).
[CrossRef] [PubMed]

J. Biomed. Mater. Res. A (1)

R. R. Gallagher, S. G. Demos, M. Balooch, G. W. Marshall, and S. J. Marshall, “Optical spectroscopy and imaging of the dentin-enamel junction in human third molars,” J. Biomed. Mater. Res. A 64A(2), 372–377 (2003).
[CrossRef] [PubMed]

J. Biomed. Opt. (2)

V. V. Ghukasyan, Y. Y. Hsu, S. H. Kung, and F. J. Kao, “Application of fluorescence resonance energy transfer resolved by fluorescence lifetime imaging microscopy for the detection of enterovirus 71 infection in cells,” J. Biomed. Opt. 12(2), 024016 (2007).
[CrossRef] [PubMed]

M. H. Chen, W. L. Chen, Y. Sun, P. T. Fwu, and C. Y. Dong, “Multiphoton autofluorescence and second-harmonic generation imaging of the tooth,” J. Biomed. Opt. 12(6), 064018 (2007).
[CrossRef] [PubMed]

J. Dent. (2)

T. T. Huang, A. S. Jones, L. H. He, M. A. Darendeliler, and M. V. Swain, “Characterisation of enamel white spot lesions using X-ray micro-tomography,” J. Dent. 35(9), 737–743 (2007).
[CrossRef] [PubMed]

N. Efeoglu, D. Wood, and C. Efeoglu, “Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel,” J. Dent. 33(7), 561–567 (2005).
[CrossRef] [PubMed]

J. Fluoresc. (3)

H. C. Gerritsen, R. Sanders, A. Draaijer, C. Ince, and Y. K. Levine, “Fluorescence lifetime imaging of oxygen in living cells,” J. Fluoresc. 7(1), 11–15 (1997).
[CrossRef]

S. E. D. Webb, S. Leveque-Fort, D. S. Elson, J. Siegel, T. Watson, M. J. Lever, M. Booth, R. Juskaitis, M. A. A. Neil, L. O. Sucharov, T. Wilson, and P. M. W. French, “Wavelength-resolved 3-dimensional fluorescence lifetime imaging,” J. Fluoresc. 12(2), 279–283 (2002).
[CrossRef]

K. Koenig and H. Schneckenburger, “Laser-induced autofluorescence for medical diagnosis,” J. Fluoresc. 4(1), 17–40 (1994).
[CrossRef]

J. Microsc. (1)

G. McConnell, J. M. Girkin, S. M. Ameer-Beg, P. R. Barber, B. Vojnovic, T. Ng, A. Banerjee, T. F. Watson, and R. J. Cook, “Time-correlated single-photon counting fluorescence lifetime confocal imaging of decayed and sound dental structures with a white-light supercontinuum source,” J. Microsc. 225(2), 126–136 (2007).
[CrossRef] [PubMed]

J. Phys. Chem. (1)

V. V. Ghukasyan and F. J. Kao, “Monitoring cellular metabolism with fluorescence lifetime of reduced nicotinamide adnine dinucleotide,” J. Phys. Chem. 113, 11532–11549 (2009).

Lasers Med. Sci. (1)

E. Borisova, T. Uzunov, and L. Avramov, “Laser-induced autofluorescence study of caries model in vitro,” Lasers Med. Sci. 21(1), 34–41 (2006).
[CrossRef] [PubMed]

Med. Laser Appl. (1)

R. Hibst, R. Paulus, and A. Lussi, “Detection of occlusal caries by laser fluorescence: basic and clinical investigations,” Med. Laser Appl. 16(3), 205–213 (2001).
[CrossRef]

Microsc. Res. Tech. (2)

W. Becker, A. Bergmann, M. A. Hink, K. König, K. Benndorf, and C. Biskup, “Fluorescence lifetime imaging by time-correlated single-photon counting,” Microsc. Res. Tech. 63(1), 58–66 (2004).
[CrossRef] [PubMed]

F. J. Kao, “The use of optical parametric oscillator for harmonic generation and two-photon UV fluorescence microscopy,” Microsc. Res. Tech. 63(3), 175–181 (2004).
[CrossRef] [PubMed]

Nat. Biotechnol. (1)

P. J. Campagnola and L. M. Loew, “Second-harmonic imaging microscopy for visualizing biomolecular arrays in cells, tissues and organisms,” Nat. Biotechnol. 21(11), 1356–1360 (2003).
[CrossRef] [PubMed]

Nat. Methods (1)

F. Helmchen and W. Denk, “Deep tissue two-photon microscopy,” Nat. Methods 2(12), 932–940 (2005).
[CrossRef] [PubMed]

Opt. Express (2)

Photochem. Photobiol. Sci. (1)

C. Hille, M. Lahn, H.-G. Löhmannsröben, and C. Dosche, “Two-photon fluorescence lifetime imaging of intracellular chloride in cockroach salivary glands,” Photochem. Photobiol. Sci. 8(3), 319–327 (2009).
[CrossRef] [PubMed]

Proc. Natl. Acad. Sci. U.S.A. (2)

A. Zoumi, A. Yeh, and B. J. Tromberg, “Imaging cells and extracellular matrix in vivo by using second-harmonic generation and two-photon excited fluorescence,” Proc. Natl. Acad. Sci. U.S.A. 99(17), 11014–11019 (2002).
[CrossRef] [PubMed]

W. R. Zipfel, R. M. Williams, R. Christie, A. Y. Nikitin, B. T. Hyman, and W. W. Webb, “Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation,” Proc. Natl. Acad. Sci. U.S.A. 100(12), 7075–7080 (2003).
[CrossRef] [PubMed]

Proc. SPIE (1)

K. Koenig, R. Hibst, G. Flemming, and H. Schneckenburger, “Laser-induced autofluorescence of caries,” Proc. SPIE 1880, 125–131 (1993).
[CrossRef]

Other (2)

J. R. Lakowicz, Principles of fluorescence spectroscopy, 3rd edition. (New.York: Plenum Press, 2006)

A. R. Ten Cate, Oral Histology 3rd ed. (Mosby, St. Louis, 1998), Chap. 5.

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Figures (5)

Fig. 1
Fig. 1

(A) The autofluorescence image near dentin-enamel junction. Dentin tubules and enamel prisms can be seen clearly. Both dentin and enamel emit strong autofluorescence under two-photon excitation. E: enamel, D: dentin. (B) The AF spectra are obtained from 5 selected regions in enamel (green) and dentin (blue). The SH at 375 nm appears only in dentin. The scale bar is 100 μm

Fig. 2
Fig. 2

(A) High resolution autofluorescence image near dentinoenamel junction and enlarge view of the selected region in enamel. DEJ: dentinoenamel junction. The scale bar is 50 μm. (B) the corresponding FLIM image; 128 × 128 pixels. The average autofluorescence lifetime is indicated in rainbow scale. (C) The average autofluorescence lifetime histogram obtained from FLIM image. (D) Representative autofluorescence decay curves from dentin (blue), enamel (green). The IRF is shown in red. Theses decay curves are fitted with double-exponential model. Their corresponding residuals (indicating a good fit) after optimal fitting are also shown.

Fig. 3
Fig. 3

(A) An epi-illuminated image of the carious dental sample used in this study. (B) the corresponding color coded FLIM image (binned to 128 × 128 pixels) that shows carious regions with greatly reduced lifetime (blue). The scale bar is 200 μm. The intensity (black) and average lifetime (red) line profiles obtain from FLIM image in (C) dentin and (D) enamel, respectively.

Fig. 4
Fig. 4

(A) The autofluorescence decay curves from point S-c1-c2 and (B) S’-c1’-c2’ shown in Fig. 3 (B). The IRF, taken with SH, is shown in red. These decay curves were fitted with double-exponential model. Their corresponding residuals (indicating a good fit) after optimal fitting are also shown.

Fig. 5
Fig. 5

(A) X-ray micro-CT image of the same carious dental sample shown in Fig. 3. The scale bar is 200 μm. (B) The relative mineral density in dentin (blue line) and enamel (green line) were calculated from the line profile indicated in micro-CT image.

Equations (1)

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τ a v = a 1 × τ 1 2 + a 2 × τ 2 2 a 1 × τ 2 + a 2 × τ 2 ,

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