[Inhibition of polymerization by oxygen in composite filling materials and enamel sealers]

The oxygen inhibition upon the polymerization of composite materials was investigated. The method permitted the avoidance of oxygen inhibition even in cases where the special matrix could not be used. The results can be summarized as follows: 1. The depth of inhibition, when atmospheric air is admitted, varies, according to different brands of composites, between 25 and 105 mum. 2. By conducting a protective gas over the surface of the polymerizing material, the contact of oxygen is avoided just as if a matrix were used. 3. Avoidance of oxygen is particularly important during the setting period of the material, i.e. the time between the end of mixing and the end of setting. 4. Polymerization under a protective gas makes it possible to polymerize even very thin layers of material and therefore widens the scope of use for sealants in caries prophylaxis.