Hi.. Thanks for the query.. I have gone through your query and can understand your concerns.. As per your complain DRY MOUTH or XEROSTOMIA caused due to composite filling has very rare chances and has not been documented in even few of the patients and even in your case if seems questionable.. You should consult an Oral Physician and get evaluated as Dry mouth can occur due to a number of reasons like Salivary gland disorders, nerve damage that supply salivary gland, stress, allergy to large number of medicines, radiotherapy or chemotherapy for cancer,hormonal changes like in pregnancy, menstruation and menopause etc.. In case if there is any underlying cause diagnosed for dry mouth treatment of the same can relieve the dry mouth while in case if there is nothing found then you can get the composite filling removed and get a temporary filling done.. In case if the condition starts improving then composite is the culprit and then you can get another filling done with material like Glass Ionomer Cement. As of now you can take saliva stimulants like Lemon drops, sour candies and sugar free chewing gums for stimulating saliva flow. Saliva Substitutes are available with the chemists known as Artificial Saliva that contains Methylcellulose and can be instilled in mouth to lubricate the mouth.. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora..