A caries detector (synonyms: caries detector; caries finder) is a liquid consisting of a solvent with a defined molecular size and a dye. The solution is used to check a carious lesion (a hole) after excavation (caries removal) and before further restorative (filling) treatment to ensure that no residual carious dentin (tooth bone) remains.
Caries detector solutions are offered by a number of manufacturers. What they have in common is a solvent, for example propylene glycol, which, due to the defined size of its molecules, can penetrate necrotic dentin (dead dentin) and dentin penetrated by bacteria, but not healthy dentin or only demineralized dentin, from which only the hard substance components have been removed by the acid attack of the bacteria causing caries. The dye transported along with the caries, e.g. erythrosine 1%, in turn serves to mark the corresponding dentin area and to visually distinguish it from the dentin worthy of preservation.
Indications (areas of application)
A caries detector differs from other methods of caries diagnosis, such as radiography, fiberoptic transillumination, or laser fluorescence, in that it is used during the treatment of a carious defect rather than in a dental checkup.
Even without using a detector liquid, it is possible for the experienced dentist to distinguish soft, demineralized dentin, which is therefore to be removed, from still mineralized, hard dentin by using the so-called tactile method and scanning the excavated defect with a dental probe under slight pressure, thus sensing the different surface properties. In addition, the so-called cri dentaire (“tooth cry”), a typical sound when probing mineralized dentin, is a sure sign of successful excavation (caries removal).
Thus, the use of a caries detector is not a conditio sine qua non (indispensable condition), but it is a very useful adjunct to excavation control.
The procedure
- Opening the previously diagnosed carious lesion by removing the enamel cover, e.g., with rapidly rotating diamond instruments
- Excavation (caries removal) e.g. using slowly rotating rose burs that chip away carious material, or using other excavation methods
- Application (application) of the detector solution
- Reaction time depending on the preparation 10 to 20 seconds.
- Spraying off depending on the preparation for 10 to 20 seconds. After spraying, only the detector solution transported into the infected dentin structure remains.
- Visual inspection and, if necessary, removal of residual caries.
- Restorative (filling) care of the defect.
Possible complications
One problem is the fact that near the pulp (near the pulp), of all places, the dentin structure changes, due to the fact that the density of the dentinal tubules (microscopic tubules that cross the dentine to the pulp) increases. The healthy dentin close to the pulp thus accepts the dye more easily than healthy dentin further away. However, the treatment goal of an excavation is not only the complete removal of the caries, but also the preservation of the hard tissue roof over the pulp (the tooth pulp). Therefore, in the vicinity of the pulp, the practitioner should dispense with color marking by the detector and rely only on the tactile method and the typical probe sound.
