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How to clean a hamster's teeth
Start with the right food.
Feed your hamster a hard food, such as a store-bought pellet food or seed mixture. There are many different varieties available at pet stores that are specially formulated to meet the nutritional needs of hamsters.
Avoid feeding your hamster soft foods unless he has some kind of dental disease that makes it difficult to chew. Don't give your hamster any food that has been ground up, as the small particles can get stuck between his teeth, causing cavities.