As the emphasis shifts from damage mitigation to reversal of early disease in the oral cavity, the need for sensitive detection and diagnostic tools become more important. Optical diagnostics have higher value of sensitivity proving its promising role as a screening aid. Newer techniques are being introduced to improve the specificity of optical diagnosis. Light-based imaging of the tissues detects minimal changes such as (i) cell microanatomy, e.g. nuclear/cytoplasmic ratio, (ii) expression of specific biomarkers. These properties are ideal for the detection of early changes, for assessing the margins of lesions and, for repeated non-invasive monitoring of existing lesions. In the presentation, the principles behind optical diagnostic approaches, and their potential usefulness as a tool in the diagnosis of oral lesions, and other pathologies will be reviewed.

1. OPTICAL DIAGNOSTICS IN
DENTISTRY
Presented by
S.Nagarajan,
Ragas dental college,
Chennai.

2. INTRODUCTION
Light is thrown on the surface of oral mucosa;
DIAGNOSIS
SEE MUCOSA FOR OPTICAL CHANGES
SEE COMPUTER FOR THE CELLULAR
STRUCTURE OF MUCOSA
Delineate
Diagnose

3. 1. Auto fluorescence
2. Chemiluminescence
3. Photosensitization
4. Qualitative Light Fluorescence(QLF)
5. Optical Coherence Tomography(OCT)

4. 1. Auto fluorescence
Based on the inherent capacity of normal mucosal
cells to emit light when exposed to fluorescent light.
VELscope

5. Clinical efficacy:
 Margin of lesion is clearly demarcated.
Advantages:
 On spot result
 Repeatability.
Short comings:
o Can’t differentiate cancer and other
pathologies like apthous ulcers
o Heat from prolonged examination
o Mutagenicity of the light used.
1. Auto fluorescence (cont..)
SENSITIVITY SPECIFICITY
93% 91.4%

6. 2. Chemiluminescence
After a chemical treatment abnormal mucosal cells reflects light when
illuminated, based upon their keratin content and N/C ratio.
Vizilite

7. SENSITIVITY SPECIFICITY
83.3% 76.9%
Clinical efficacy:
 Higher sensitivity to leukoplakia.
Advantages:
 Real time results
 Low cost.
Short comings:
o Low sensitivity for red lesions
o Acetic acid increases salivary flow
interfering the reflectance
o Needs dark environment.
2. Chemiluminescence (cont..)

8. 3. Photosensitization
Photosensitizers(amino levulinic acid) have affinity towards cancer
cells and fluoresce with them under specific wavelengths.

9. Clinical efficacy:
SENSITIVIY SPECIFICITY
93% 95%
 Being used successfully for diagnosing bladder cancer and
to treat actinic keratosis
 Not only diagnoses, but it can also treat cancer
Advantages:
 Guiding tool for biopsy
 More sensitivity for cancer
Short comings:
o Prolonged systemic photosensitivity
o Low sensitivity at inflammation site
3. Photosensitization (cont..)

10. 4. Qualitative light fluorescence (QLF)

11. 5. Optical coherence tomography(OCT)
Employs reflected signals from different layers of the tissue to make
out the microscopic image of the mucosa.

12. CLINICAL EFFICACY:
1. Diagnosing Oral Squamous cell carcinoma
2. Monitoring Cancer therapy induced mucositis

13. 4. OCT in caries diagnosis
5. In detecting hemangiomas and vascular malformations
6. In monitoring the prognosis of treatment of Gastro Oesophageal
Reflux Disease (GERD) with proton pump inhibitors.
3. OCT in Periodontal disease diagnosis

14. 7. OCT in Endodontic magnification;(modified to have 0.5mm probe)

15. Other applications of OCT;

16. Naked eye
examination
Late
diagnosis
70%
Mortality
5 yrs.
No improvement in
mortality rate for
the past 30 yrs.
Misses
out for
each
15-20
yrs.

17. CONCLUSION

18. REFERENCES;
1) Optical diagnostics in the oral cavity: an overview;
P Wilder-Smith, J Holtzman.
2) ViziLite Plus;
Faqs Myles Williams, Atlanta Denta.
3) Fluorescence spectroscopy;
Wikipedia.
4) Photocure announces expansion of Hervix;
http://www.velscope.com/
5) Debate & opinion; Should the Dentist Adopt the Use of
VELscope for Routine Screening for Oral Cancer?
Ben Balevi, BEng, DD
6) Confocal microscopy and multi-photon excitation microscopy of
human skin in vivo;
BarryR.Masters
7) Utility of chemiluminescence in the detection of oral potentially
malignant disorders and benign keratosis;
K.H.Awan, P.R.Morgan and Swarnakulasuriya
8) Light induced fluorescence evaluation: a novel concept for caries
diagnosis and excavation;
Neeraj Gugnani, IK Pandit, Nikita Srivatsava, Monika
Gupta.