This non-destructive method measures and quantifies changes in mineral content of tooth tissue by detection of porphyrins, indicating cariogenic bacterial activity. Ideal for fast assessment of oral health and oral hygiene efficacy. Making QLF the only method available able to safely measure and monitor oral health.



Quantitative Light-Induced Fluorescence (QLF) visualises the contrast between sound and pathogenic tissue in the oral cavity. It is based on the principle that various (organic) substances in the mouth absorb light of a certain wavelength and then re-emit the absorbed energy at a different wavelength. By filtering the illuminating light a fluorescent or QLF™ image is obtained. In these images de-mineralized areas (e.g. white spots) show up as dark-spots, where loss of fluorescence correlates with mineral loss. Areas covered with porphyrins, generated by (anaerobic) cariogenic bacterial activity, show up brightly red/orange. These effects can be observed visually, analysed and quantified by the proprietary software and documented digitally.


• Illuminates the dentition with blue light at a peak-frequency of 405nm

• Discloses cariogenic bacterial activity by fluorescent light

   and a filter instead of disclosing agents

• Supports early detection of oral anomalies

• Quantifies the presence of mature plaque, caries, calculus and tooth cracks

• Allows for quantitative and longitudinal monitoring of demineralization

   and remineralization processes

• Provides an objective measure for caries risk

• Provides innovative solutions for prevention, treatment and treatment evaluation

• Strongly improves patient compliance

• Is endorsed by the Dutch Healthcare Authority

• Is profoundly validated (>400 scientific articles)

• Is a completely safe optical technology, without harmful radiation

Clinical examples
Normal images and Qray images* 


QLF™ capturing devices are used by Q-Ray™ software to acquire QLF™ and white light images. For the demanding professional and researcher the Qraycam™ Pro is the device of choice. The Qraypen™ is a versatile intra-oral camera that is ideal for zooming in on specific tooth surfaces.

Advantages to the dental professional:

• QLF™ provides an objective, longitudinal, quantitative oral health                                 assessment method, improving the quality of care and facilitating the                             development of patient oriented preventive care programs

• QLF™ Strongly improves patient communication

• QLF™ helps to calibrate the members of the team and greatly facilitates

   peer-reviewed consultation

• QLF™ can be used as indication for X-Rays to support the ALARA principle

   (As Low As Reasonable Achievable) to minimize the exposure of patients

   and staff to harmful radiation

• QLF™ protocolled use allows for monitoring the effects of a customized care                   program and documents the efficacy of preventive actions

• QLF™ makes delivered care more transparent.

Advantages to the patient:

•  Better understanding of oral health processes and hygiene efficacy efforts

•  Easily comprehensible feedback by clear QLF™ images and quantified data

•  Faster treatment plan acceptance

•  Easy self-check and check of family members regarding oral hygiene                            effectiveness. Bright orange-red areas that cannot be brushed away are a                      clear indication to contact a dental professional for health assessment.

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