Samples of fossil tooth enamels taken from different depths of Karain Cave (Antalya, Turkey) were studied by the ESR method. The accumulated doses (D(E)s) of the samples were determined using the paramagnetic center at g = 2.0020 +/- 0.0003 by means of three different microwave power conditions. It is found that the dating signal at g = 2.0020 (Delta Hpp approximate to 0.34 mT) is disturbed significantly by the isotropic signal at g = 2.0007 +/- 0.0003 at high microwave power. The lifetime of this signal is significantly smaller than the lifetime of the dating signal. However, the statistical uncertainty caused by different microwave powers is still within the total uncertainty in the age determination of the tooth enamels under investigation. The ESR ages of the samples were calculated using early uranium (EU) and linear uranium (LU) uptake models. The ages due to EU and LU models are in agreement within an error of 10% due to the low uranium content of the samples.