This paper presents the effects of different radiation characteristics on the Specific Absorption Rate (SAR) values induced within a 2mm resolution, anatomically detailed, realistic model of human head by including a metallic spectacle frame and metallic tooth caps. The head is illuminated by a plane wave source with seven different frequencies from 500MHz to 2500MHz, with five different incident directions and three polarizations. The electromagnetic (EM) fields are computed using the Finite-Difference-Time-Domain (FDTD) method. The calculated local SAR values are averaged over 1 g and 10g tissues as proposed by IEEE standards. It is shown that, the existence of a metallic spectacle frame causes an increase in the SAR values. However, the results indicate that, metallic tooth caps have negligible influence on the SAR values.