HELLO,

Thanks for posting your query.

Yellowish teeth appears due to many reasons-

Poor oral hygiene maintenance resulting in plaque and calculus deposits .
Flurosis.
Dentinal hyperplasia.
Medications like tetracycline.
Depending on the cause of yellowish discolouration,treatment can be planned.

I would suggest you to get a thorough scaling done by a dentist to remove the plaque and calculus deposits.
please stop using fluridated water/fluridated toothpaste if you practice any.
If the discolouration is present by birth,scaling won't remove the discolouration.
In such cases,

Bleaching/veneering/porcelain crown has to be placed depending on the severity of the condition and aesthetic requirements.
Meanwhile,maintain good oral hygiene.
Brush your teeth twice daily.
Stop or replace the medications causing discolouration after consulting your physician,if you are practising any.
Use chorhxidine mouthrinses to prevent plaque accumulation.

I would suggest you to visit a dentist whenever feasible for further treatment.

Hope this helps.
Please feel free to ask further concerns if any.
Take care.
Dr XXXXXXX XXXXXXX

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