1. Chemo really has no bearing on damage to teeth. However, if you do not have saliva or constant dry mouth, that is prone to cause more decay to your teeth. Your mouth has to stay moist to help eliminate the cavity causing germs.2.. Chemo really has no bearing on damage to teeth. However, if you do not have saliva or constant dry mouth, that is prone to cause more decay to your teeth. Your mouth has to stay moist to help eliminate the cavity causing germs. 2.