Dentigerous cyst presenting as facial pain.

A rare case is presented in which a maxillary dentigerous cyst had eroded the posterior wall of the right maxillary sinus into the pterygo-palatine fossa causing facial pain due to pressure on the nerves. It had also eroded the lateral wall of sinus and into the oral cavity and got infected resulting in foul smelling oral discharge. The case was dealt with complete removal of cyst using Caldwell Luc's approach.