Apparatus for the polymerisation of any light curing synthetic resins used in the dental industry. Thanks to the integrated overheating protection the polymerisation temperature remains constant and does not rise above 40° C. The rotating plate ensures that the curing and the effect of light are uniform, whereas the individual combination of lamps provide reliable and homogeneous curing. The lamps have a service life of up to 1.000 h and are easily to be replaced. An acoustic signal indicates the end of the polymerisation process. Additionally, an operating time counter is provided.