Can using a mouthguard at night give you cavities? because it drys out your teeth

Mouthguard and deca: No, a well made bite guard should not give you cavities. Usually mouth-guards allow the flow of saliva through the teeth, particularly at the tooth-gum interphase. Dryness of the mouth may be due to mouth breathing. Xerostomia (dry mouth) does cause an increase in the incidence of cavities.

Not likely: A bruxism appliance in and of itself does not dessicate your teeth. It is very important that before the appliance is inserted that you brush and floss very well, removing food and accumulated plaque. If you don't then the appliance will cover the bacteria and food and that could cause bacterial acids to be concentrated on your teeth, causing cavities. You may have a dry mouth from other reasons.

Not really: If you brush and floss before you go to bed your teeth are clean. Saliva naturally decreases while you are asleep so your mouth will always be dry when you wake up. You would increase your risk of cavities if you drank or ate a sugery substance, then put the mouthguard in. It would prevent any saliva from washing the teeth. Then again eating before you go to bed is a no-no.

Not the correct ones: There are basically 4 types of mouth wash! prescription (anti microbial or fluoride), otc fluoride, otc antiseptic or ones to freshen your breath. While i can't say specifically for the last one, the first 3 groups are all beneficial and in conjunction with proper brushing and flossing will make your mouth healthier! so rinse on & don't forget the brushing and flossing!