[Must caries be completely removed?]. / Muss Karies vollständig entfernt werden?

Changes in restorative techniques and the development of new restorative materials have allowed the use of more conservative cavity preparations. Important questions are: What are the consequences of incomplete removal of caries-affected dentin? What are the bond strengths of adhesives to demineralized enamel and dentin? The non-invasive management of carious lesions with intact tooth surfaces in a manner that will bring about some remineralization offers a viable and superior alternative to conventional restorations. The bond strengths of adhesives to demineralized enamel seem to be similar to that on normal enamel. None of the modern filling technologies can guarantee the arrest of the carious process. The complete removal of the infected dentin is, however, still necessary irrespective of the restorative material used.

[The periodontally affected tooth from the restorative aspect]. / Der parodontal geschädigte Zahn aus der Sicht der Zahnerhaltung.

On each periodontally affected tooth with loss of attachment caries lesions may develop under bacterial plaque on the root surface. The prevention of root caries follows the rules of prevention for crown caries: 1) optimized oral hygiene, 2) reduced intake of fermentable carbohydrates, and 3) fluor treatment. Successful periodontal therapy can prevent root caries with good professional management of the patient and/or adequate preventive measures on the part of the patient. If root fillings become necessary aspects of secondary caries prevention, like good margins and fluor treatment, and filling/margin/periodontium are of utmost importance. Progressive periodontal disease might affect pulp tissue. Careful endodontic monitoring of the tooth is indicated. There are yet no established measures for the treatment of dentin hypersensitivity after periodontal treatment.

[Curing ability of polymerization lights for composite materials]. / Durchhärtungsleistung von Polymerisationslampen für Kompositmaterialien.

An in-vivo study has been conducted with four different brands of activator light sources. 38 light units in service by different dental practitioners were compared with new light sources. Curing depth profiles were obtained using Knoop microhardness measurements. It was observed that with an exposure time of up to 60 s the polymerization was not sufficient below 2 mm of depth. The "old" light sources showed worse curing properties than the new ones, especially below this depth. Generally, the polymerization units with rigid glass fiber light guide showed better results than the units with a flexible fiber-optic cable. Other reasons for insufficient polymerization were polymerized composite material at the end of the light guide, a defect in the cooling system of the light source and, for two brands of light sources, a reduction of the voltage below 220 V.