Im rather new at Blender and i have a little issue when i render my model. As you can see in the next image:

When i render my model after applying textures, only these two parts of the complete model (villager7_eyes and villager7_mouth) show strange granulated triangles and some of them are black. I've checked the normals and all of them are pointing outside the triangles, so what am i doing wrong?
Thanks in advance for replying
W> Remove doubles in Edit mode with all selected), and probably these faces use flat shading (in Edit modeW> Shade Smooth). – Mr Zak Nov 13 '15 at 19:15