Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... As per your complain and presentation of symptoms it is commonly seen in individuals who snore during sleeping has a habit of sleeping with mouth open and has a tendency towards mouth breathing.. Experiencing dry mouth at night time also makes the diagnosis confirmed that you have a dry mouth secondary to mouth breathing.. The dry spot in the inside of lower lip is also due to dryness of mucosa and should be taken care of.. The best way to make the condition resolve is by sleeping with closed mouth to stimulate or force nasal breathing.. This can be done by sticking a vertical strip of doctor s tape or Micropore tape over the closed lips before sleeping.. This will keep the mouth closed and prevent dryness as well as reduce snoring.. The dry spot will also gradually improve.. Drink plenty of water and as of now you can chew sugarfree chewing gums as it will stimulate saliva flow and the dry spot will resolve faster.. It does not seem to be due to chewing tobacco and you need not to worry about it.. If after following the above advised instructions the dry spot does not resolve then you should consult an Oral Physician and get evaluated.. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora..