Hello, I'm a Pediatric Dentist. Stains or marks on primary teeth can be due to multiple factors. As mentioned by you, iron drops can cause minor staining, caries also cause jet black stains in teeth. You can allow him to brush his teeth first and then you can brush his teeth by telling him that you can see germs on his posterior teeth. Use a soft toothbrush or a finger tooth in the teething area.

Share some clear photographs of effected area. Black stain could be due to early carios, or may be staining. You need to consult doctor online or offline for better guidance and treatment options. Encourage your child to drink a lot of water, try to brush his or her tooth properly. Still have queries then you can consult.

Hello madam,       Hope you are doing good. Please stay calm. They are milk teeth and are very much prone for stains. Please make sure he brushes his teeth or else you yourself brush his teeth by distracting. If he is not at all allowing atleast use a drop of paste in your hand to brush. Nothing will go wrong.Use very soft tooth brush of any brand and cheerio paste will be intresting for kids with its appearance and taste.

Hello dear Please be calm See i Suggest you to please share pic for confirmation of diagnosis and best treatment Some black stains are due to chromogenic bacteria They will not cause any issues For further details you can consult me Thanks

Any ultrasoft brush with baby paste of any brand can do good, the thing is you try to help him brush the teeth. If it is only the stains nothing much to worry. Make sure he doesn't develop cavity in teeth.