I having found that problem .Once I done mine last year with the agent. That was the end. Just renewed it myself last week for another year. Little bit of effort getting all the paperwork together. But was in immigration for approx one hour all done and sorted
Last time dentist here . Cost 5000 baht for two false teeth on a plate . Might give you some idea of the cost . Or other wise get some on to chew your meat first 😀😃