I diagnosed my symptoms and anti-ssro antibodies with sjgren's syndrome. i did a scintigraphy of the salivary glands, and the result: the salivary glands are working fine. how is it possible and i recently had white tongue fungus due to dryness?

Keeping your mouth wet is a function of all glands, including parotid. Did the scan include the parotid. If so maybe it is the dry air in URA or you have OSA. I suspect anti-SSRo antibodies is not 100% specific for Sjögren's syndrome. Discuss with the lab and your Drs.

Would suggest that you see a specialist in Oral Medicine for supportive treatment. Your local Dental Society can give you a list of Oral Medicine Specialists.