Comparison Of Light-Curing-Modes On The Adaptation Of Composite To Dentin K.Glockner*, M.E. Reich, K.Ebeleseder, H. Hulla, P. Städtler (University Dental Clinic of Graz, Department of Conservative Dentistry Auenbruggerplatz 6A, A-8036-Graz, Austria) Objectives The study was the quality of marginal adaptation after polymerization with the plasma lamp in comparison to conventional- and softstart-halogen light curing.   Method In freshly extraced sound molars 33 round standard cavities with a C-factor of 5 were prepared in dentin. They were filled with Z-100 and Scotchbond-1 and cured in three different modes. One group was cured with a halogenlamp by high intensity light for 40 s, one group by softstartpolymerization for 40 s and the third group was polymerized with the plasmalamp for 2 times 3 s. After thermocycling for 1500 times replicas were made and the rate of perfect margins was examined in the SEM.   Key results The rate of perfect margins for conventional curing was 99,1%, for softstartpolymerization was 98,9% and for the plasmapolymerization was 74%.   Conclusion Curing resins with the plasmalamp creates a high rate of imperfect margins. Related to this kind of cavity design the difference between softstart and conventional curing was not statistically different. High intensity curing with the plasma lamp cannot recommended ad this time.