Hi
yes it looks like stains due to chromogenic bacteria..
you need to go for scaling (teeth cleaning)
STEPS TO MINIMIZE CHROMOGENIC BACTERIA STAINS:
1. Avoid sticky foods like chocolate biscuits, chocolate drinks, tea
2.Effective tooth brushing twice or thrice a day
3.Regular visit to dentist for teeth cleaning every 6 months
However kindly check for suface caries due to dimineralization
Next Steps
kindly visit dentist for furthur clinical examination and management