Find caries with light, I love this game!

30 Mar 2017 - 47416

Finding caries present in our patients’ mouths is one of the main, basic task of our examination. Although other diagnostic tools and parameters are often used to this end, finding caries with light can be a viable, effective, risk free option, even in younger patients. In dentistry, research and development of new materials and technologies reach for better prevention and early treatment of dental diseases.

In this context, the concept of “minimally invasive dentistry” is gaining space, a discipline that has its main goal in the respect of the healthy tooth tissue and has the treatment of primary and secondary lesions at the very early stage as a priority.

Careful diagnostic investigation, correct assessment of the biological risks/benefits and – last but not least – the conservative and highly specific removal of decayed tissue, preliminary measures are very important for the achievement of these results.

It is essential that the diagnostic path start from a proper clinical and radiological investigation through conventional diagnostic tools complemented by innovative tools in order to make otherwise clinically hidden lesions visible.

The observation that the enamel, dentin or decayed tissue, exposed to a laser light, emit a specific spontaneous fluorescence made it possible to develop devices that, using laser technology, allow us to attribute a “grading” to the carious lesion severity, which is a prerequisite for subsequent operational choices, more or less favorable to the intervention, both to monitor the evolution in time of the carious pathology and/or the effectiveness of the treatment.



Fig. 1

Give your patients the opportunity to understand the diagnostic process, let them do diagnosis with you: they will just love it. Communication is something that we absolutely need and owe our patients, and digital communication by images is the best solution, as it is easy both to understand and to make our usually non-understandable speeches simple and clear.

Fig. 2

We’ve been using transillumination on anterior teeth for many years, now: it is easy to show our patients through a mirror how teeth appear transparent with a backlight, but in order to show them the posteriors we need something else, something new.

Fig. 3

There is one device (Diagnocam, Kavo) which uses laser-induced transillumination making us able to obtain an occlusal view, expressed in a gray scale, of the tooth surface. The different dental tissues react to light differently: the enamel is clear, dentin is slightly grayer, while cavities appear much darker. The DiFOTI, Digital Fiber Optic Trans Illumination, technology uses a source that produces a specific wavelength (near infrared) light.

Fig. 4

Diagnocam view: it is easy for us and for the patient to understand that healthy tissues appear white, clear while a black, dark appearance is not healthy. That said, it is easy for you to understand how cooperative the patient will be through the whole restorative procedure. This technology allows you to intercept lesions at an early stage. In between black and white there is gray though: gray is a color full of ACTIVE CARE and needing monitoring, and the time invested into registration and control of lesions allows us to stop them at the enamel layer, enhancing the role of information and patient motivation.



Fig. 5

The laser light coming from the alveolar bone passes through the tooth, while a special camera records images/videos and a software organizes this data creating files you can easily show on your display to share information with patients.

Fig. 6

Processed images might look unfamiliar in the beginning

Fig. 7

First of all, in order to communicate with the patient, we can show where the dentin-enamel junction is and clarify when the lesion becomes irreversible.

Fig. 8

The sulcus is one of the anatomically most complex areas of the tooth. We can evaluate if something is happening under the sulcus and get a glimpse on the extension of the lesion.

Fig. 9

Initial picture and pre operative Rx. Hidden caries: occlusal dentin caries that is missed on a visual examination and X-ray but is large enough and demineralized enough to be detected by light (Diagnocam).

Fig. 10

Step by step cavity opening.

Fig. 11

The extension of the lesion.

Fig. 12

The cavity is now clean and the restoration can be completed.

Fig. 13

It is possible to use a dedicated laser (Diagnodent Pen) to do diagnosis in the sulcus area: if the numeric value is bigger than 25, it means there is a carious process going on.

Fig. 14

Cavity clean and restoration completed.



Fig. 15

On the left, pre-operative view, in the centre a Diagnocam view, on the right a bite-wing Rx.

Fig. 16

The occlusal view allows us to see the actual size and shape of an occluso-interproximal cavity. In general, while Rx usually underestimates the extension of a carious lesion, transillumination shows them in a 1:1 relation, without underestimating the size of a cavity.

Fig. 17

Rx on the left (bitewing size 3) and DiFOTI view on the right.

Fig. 18

Before, during and after the treatment.

Fig. 19

Rx and DiFOTI.

Fig. 20

Step by step in cavity preparation.

Fig. 21

Sonic tips to define the cavity and to preserve and not to touch the neighboring tooth.

Fig. 22

Matrix in place.

Fig. 23

Final view and Rx.



Fig. 24

This device can reveal micro-leakage in the restoration margins.

Fig. 25

A Custom Ring can be just perfect with Diagnocam. Step by step, as described in Jordi Manauta’s article, we can record the marginal crest shape into the customized ring.

Fig. 26

Cleaning the cavity in a mini-invasive way is a piece of cake as, guided by DiFOTI it’s like setting navigation to the most strategical place to preserve sound tissue.

Fig. 27

Cavity with the custom ring in place (left), post operative image (centre).



Fig. 28

A small and a medium acid ampoule.

Fig. 29

A small, a medium and a large acid ampoule.

Fig. 30

View of a single crack.



Light is a patient-friendly tecnology, totally safe for the patient and
it represent a way to do clear diagnosis and to have a new and easy communication with patients.
It means that we can detect early lesions and monitor them over time and manage the treatment based on the specific risk to develop caries.
It is a great opportunity for dentists and patients.


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