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I spent 3500 on upper fixed connected capped teeth, 5. Now i am told after 18 years, that the teeth under neath are decayed, and need to be removed along with the two o each end and my wisdom teeth. I am scared, i have never had more than one tooth pulled at one time. I also would be getting fitted for dentures first. I dont understand why some dentist say they put a liner in at first, and change the liner after they my mouth heals. Other dentist say they make a mock set of dentures, immediates, and a permanent set after my mouth heals. why the difference?