Your description is not very precise but one thing is for sure that you have been delaying your treatment for a pretty long time. You need multiple treatments and they should not be delayed till symptoms appear. As far as the treatment cost is concerned, it varies from dentist to dentist depending upon their experience, the techniques and the materials used. Please visit the dentist for a proper clinical evaluation..... the best treatment options can be explained to you after that only. For example, removal of wisdom tooth can cost you anything between 2000 and 10000 depending upon the condition of the tooth and the bone root orientation. Regards.