Very frequently it is associated with a fungal infection at this age. High chances if she's a diabetic and denture wearer. However any mouth burning should be looked into at immediately to rule out multiple causes. Final therapy will be based upon having a look, investigating the cause and correct medication. make sure you get a complete blood profile along the visit.

Is she wearing a denture ?? I might occur due to worn out denture. There r other causes as well. But this is also a age related problem. There r medicines available for the same. We can hv a check up and then can prescribe u the same.