[en] The present paper gives a brief analysis of the main results of using dielectric detectors to record-rare spontaneous-fission events due to transfermium elements. In different experiments carried out at JINR during the last 25 years and aimed at synthesizing new elements the possible use of dielectric charged-particle detectors, their principal and discrimination properties and the limiting sensitivity under the conditions of strong radiation effects were considered. It is demonstrated that the chosen detectors (mica, phosphate glass, polyethyleneterephtalate and polycarbonate) allow one to achieve a limiting sensitivity of 10^-20 g/g in detecting the formation of new nuclei. The work has been carried out at the Laboratory of Nuclear Reactions in the framework of the research program on the synthesis and study of the properties of new elements. 19 refs.; 11 figs.; 1 tab