Thank you hanna! Yes there are dishwashers that will sterilize but most arent and most plastics would not survive these temps in a dishwasher during sterilization. To achieve sterility an object must be sustained to a temp of 273.2* F for 15 minutes. Liquids and instuments wrapped in cloth will take longer to reach those temps.
This was copied and pasted from Wikipedia.
"Dishwashers do not
sterilize the utensils, as proper sterilization requires
autoclaving
at 121 °C with pressurized wet steam for at least 15 minutes.
Commercial dishwashers can use one of two types of sanitizing methods:
hot water sanitizing (using final rinse water at a temperature of at
least 83 °C (180 °F)), or chemical sanitizing (by injecting chlorine in
the final rinse water). Not all dishwashers are capable of reaching the
high temperature required for hot water sanitizing. Medical grade
dishwashers and sanitizers are starting to use ultrasonic cleaners<sup>[
citation needed]</span></sup>, which use a liquid bath treated with sonics to remove particles and sterilize instruments.
Most consumer dishwashers use a 75°C thermostat in the sanitizing
process. During the final rinse cycle, the heating element and wash
pump are turned on, and the cycle timer (electronic or
electromechanical) is stopped until the thermostat is tripped. At this
point, the cycle timer resumes and will generally trigger a drain cycle
within a few timer increments.
Most consumer dishwashers use 75°C rather than 83°C for reasons of
burn risk, energy consumption, total cycle time, and possible damage to
plastic items placed inside the dishwasher. With new advances in
detergents, lower water temperatures (50-55°C) are needed to prevent
premature decay of the enzymes used to eat the grease and other
build-ups on the dishes. This also saves energy and can allow the
washer to be hooked directly to the hot water supply for the house."
Edited by: wade 
