Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... As per your complain halitosis can occur due to a number of conditions which can occur other than poor oral hygiene like excessive intake of strong aroma foods like garlic and onion , dry mouth,smoking and tobacco chewing, stomach disorders, upper respiratory tract infections,post nasal drip, acid reflux, over intake of medicines, diabetes,oral infections like thrush etc.. In case if you suspect oesophageal thrush or stomach fungal infection consult a Gastroenterologist and get evaluated.. In case if the oral hygiene conditions are not found unsatisfactory then you should get ruled out for other causes by a physician and depending upon your age he will advise you certain investigations if required.. As of now you can maintain a proper oral hygiene by brushing twice a day, flossing and using mouthwash twice to thrice a day.. Do warm saline gargles. Chew sugarfree chewing gums which are menthol or mint flavoured and will mask bad breath.. Avoid excess of onion and garglic. Cut down on sugary foods, tea,coffee,smoking and alcohol.. Keep stress minimal.. Eat every two hours and do not starve as it also causes bad smell in mouth.. Take more of probiotics like Yoghurt and green leafy vegetables in diet.. Drink plenty of water.. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora.