Certainly, anything abnormal in the mouth should be looked at by a dental professional; the question is when. White striations on the tongue could be lichen planus, leukoplakia, hairy leukoplakia, or a number of other lesions that aren't identifiable in the current context. They could also be caused by an SLS (sodium lauryl sulfate) allergy if you've switched toothpaste brands recently to something containing SLS. Striations could be a reaction to repetitive mechanical or chemical stresses as well. Keep an eye on it for any changes. If it changes in any way at all, go into the dentist. Otherwise, mention it at your next routine dental visit.