Broken tooth.

[Rachel12345]

Hi, I'm asking for some advice for a friend. A tooth of his has broken more or less in half. It's a top tooth, just to the side of his front teeth. Hes been to his dentist and requested a crown, however his dentist has said she doesnt feel confident doing a crown, as he has a heavy bite and it will make contact with a bottom tooth, she said that's why the tooth had broken, the bottom tooth has more or less sheared it off. Shes not advised any alternative treatment, I'm concerned if the tooth goes untreated,it will become infected. I'm finding it hard to believe that a crown cant be done on the tooth. Can anyone offer any advice? Surely it's not a good idea to just leave it?