According to some resources the desiccant dusts like DE and silica gel can be repellent to roaches to some degree. They are abrasive, cutting tiny scratches into the exoskeleton and waxy layers on the exoskeleton, so I suppose it would be expected that the roach could feel this abrasion going on and might prefer to avoid those treated surfaces. On the plus side for these desiccants the toxicity to humans is extremely low, with the biggest hazard being simply skin irritation to some people where the dust may dry out the skin. 

Boric acid dust must be ingested by the roach, but this does not seem to be a problem, as roaches regularly groom themselves by cleaning off their feet and antennae using their mandibles, and take in the boric acid as they do this. Boric acid is only a stomach toxin, again contrary to some of the misinformation on the internet. Both of these dusts could be expected to last for many years when applied into a dry area, but the desiccants absolutely rely on staying dry in order to work properly. If they land on moist surfaces or excessive humidity is present they may not be available to cling to the exoskeleton of the roach. Both dusts should also be used only within voids where you can ensure the dust stays where it is applied. Boric acid is heavier, but the light and powdery desiccants could float out through holes or if applied to attics could find their way out with air circulation.