Table top dishwashers, or as a matter of fact, most (if not all) household dishwashers are not capable of complete sterilization of your dishes. Commercial dishwashers used in restuarants may come pretty close by using sanitization methods that household models do not employ.
Household dishwashers usually heat the water to 75°C in the last rinse cycle which can kill quite a few micro-organisms but does not sterilize the dishes. The detergents used in washing the dishes removes quite a bit of gunk and bacteria during the earlier stages of the wash process but the hot water stage attempts to finish the job off.
One might scoff at this revelation but consider the fact that by hand washing with detergent and cold water, one definitely would not accomplish this level of sanitization anyway. Once the dishwasher does a good job at removing the grime and food from the dishes, the sanitization process does it part well. Many dishwashers come with settings which can omit this hot water stage altogether.
More importantly, What the user should be concerned with is the fact that the washed off material from the dishes can eventaully build up inside the appliance and potentially clog nozzles and drain pipes. This build up can also harbour bacteria. It is important to clean out this gunk at least once a month for regularly used dishwashers, using detergent, baking soda and maybe hydrogen peroxide followed by a hot water cycle. This applies to your table top dishwasher as well.
