Such a cartridge is known from DE 10 2008 057 443 A1, where the functional element is a valve device.
It is known from U.S. Pat. No. 4,391,590 B1 that a functional element is designed as a cap, which is pulled over a cannula opening of a cannula duct to close the cannula section. It is disadvantageous here that the cartridge and the cap for the cartridge must be manufactured in two mutually independent manufacturing steps, wherein the cap is placed, as a rule, by hand by a person or in an automated manner on the cannula opening of the cannula section. This causes high manufacturing costs. In addition, with the cap already placed, there is a risk of air inclusions during the filling of the cartridge with the dental material, as result of which the shelf life of the dental material may be reduced and/or the quantity of the filling may show undesired variations in a comparison of a plurality of cartridges. Such air inclusions may lead to the loss of the cap, especially during transportation, because of the expansion of the air, as a result of which the storage stability is reduced. Even though the inclusion of air can be reduced when filling the cartridge without cap, there is a risk now that dental material will escape from the cannula opening of the cannula section, as a result of which dental material will be lost. This leads to higher manufacturing costs. Such cartridges are intended for single-time use especially in the field of dentistry. However, there is a risk when using caps that the cannula section will be reclosed with the cap in order to use a residual material that is preset later. There is a risk of contamination of the dental material and/or of an increased risk for infection because of its undesired reclosing of the cartridge that was once opened.
A cartridge, in which fibers or a flocking are connected to the cartridge in the area of an outlet of the cannula section, is known from U.S. Pat. No. 6,059,570. This functional element is used to apply, spread and/or burnish the dental material. It is disadvantageous here that the application of the fibers or of the flocking is carried out in an independent manufacturing step and fully independently from the manufacture of the cartridge. It is also disadvantageous that the cannula section is rigid in the area of the fibers or flocking. As a result, there is a risk that a treatment with the functional element is perceived by a patient as being unpleasant and/or painful. In addition, there is a risk that undesired injuries will develop because of the rigid design. The spreading and/or burnishing of the dental material is also made difficult by the rigid design of the cartridge and of the cannula section.
Furthermore, it is disadvantageous in prior-art cartridges that there is a risk of an especially abrupt rupture of material in case of an overstressing due to an excessively strong force or an excessively high pressure being applied to press the dental material out of the cartridge and/or the reservoir.