Fermite is a material which hardens when exposed to light, and it is used as a filler.
Applied properly, Fermite holds for about a week and protects a sanded tooth from cold and heat. Here you can see 2 teeth in the upper jaw, which have just been drilled for ceramic inlays. The dark spots on the tooth are amalgamate discolorations, not cavities, and thus do not need to be removed.
After an impression is taken the teeth are sealed up using Fermite, and are thus protected against cold and heat. Here you can see the dentist shaping the Fermite and then letting it harden under the halogen lamp.
The technician prepares a plaster model before taking the imprint and produces the ceramic inlays in the laboratory. A week after preparation the ceramic inlays are ready, you can see the temporary Fermite being removed from the teeth, and now the ceramic inlays can be inserted.Fermit