[Removal of cemented crowns and bridges using piezoelectric ultrasound]

50 cemented crowns and three-unit-bridges of 34 patients were treated by piezo-electric ultrasound. 23 of 32 crowns were removed within 10 min, 14 of 18 bridges were removed within 15 min. Crowns and bridges could be taken off after an average time of 5 min or of 12 min of ultrasound treatment, respectively. To remove the restorations only few strokes with the Treymann crown remover were required. In most cases patients felt no or only slight pain during ultrasound treatment. Restoring metal or ceramic surfaces after ultrasound treatment required final firing of the ceramic and polishing of the metal surfaces.