hi...
thanks for the query...
as you have non scrapable white deposits on your tongue, so i would suggest you to visit any oral pathologist for proper clinical examination and diagnosis...
because it can be hyperplastic candidal infection or can just be
hyperkeratosis of
taste buds...
so please go for its proper treatment after proper diagnosis...
bad breath should subside after that...
if still persists then, it can be due to oral, ENT or medical problems...
visit your
dentist for complete oral examination... sometime, grossly carious tooth is the source of foul smell... in that case it will require restorations...
or due to presence of plaque and calculus... and inflamed gums and deep pockets... in that case it will require proper scaling and root planing...
brushing twice daily with pea sized tooth paste will help... make sure that you brush your teeth AFTER MEALS instead of before meals... rinse after every meal... also use tongue cleaners...
if still persists, consult general physician to rule out any metabolic disease...
consult ENT specialist also...
hope it will help you...
take care...