clean teeth short battery life [SEP] i am enjoying this toothbrush after a good brushing job my teeth feel almost like i left the dentists the sonic waves really do dislodge plaque and leave a very clean mouthgreat for me because i travel frequently and do not feel like carrying a toothbrush chargerone odd thing though is that my first set of batteries only lasted a week i just put in a second pair of batteries and am waiting to see how long they last i brush twice a day so ordinary amount of usage i tried a pair of fully charged nimh batteries today i think all nimh rechargeables are v and the tooth brush would not start seems that it needs batteries it worked fine with ordinary alkaline batteries