RISK OF PULP DAMAGE DUE TO TEMPERATURE INCREASE DURING THERMODEBONDING OF CERAMIC BRACKETS

The purpose of this study was to perform in vitro measurements of the temperature increase at the enamel-dentine interface during electrothe rmal removal of ceramic brackets, and to analyse, in vivo, whether sig ns of pulp damage can be observed 4 weeks after the procedure. In vitr o study: a total of 29 caries-free human teeth were cut into buccal an d lingual halves. The buccal halves were bonded with ceramic brackets, and miniature thermocouples were placed from the pulpal side into hol es drilled to the enamel-dentine interface under the centre of the bra cket slot. From the onset of thermodebonding, the temperature increase relative to room temperature was recorded for a period of 43 seconds. The maximum temperature increase at the enamel-dentine interface was 6.9 degrees C. In viva study: a total of 12 human premolars scheduled for extraction for orthodontic reasons were bonded with ceramic bracke ts. Electrothermal debonding was performed the following day. After 4 weeks, the teeth were extracted and prepared for histological examinat ion. Following demineralization, sections were prepared for light micr oscopic examination. No signs of pulpal inflammation were observed.