Análise Termográfica de Dentes Obturados com Diferentes Técnicas

Abstract

Introduction: Different root canal obturation techniques have already been proposed, but with similar performance in terms of adaptation, leaving the concern about the supporting tissues and the damage caused to them by the increase of temperature during obturation. Objective: To evaluate the thermal behavior of the external surface of roots filled with different techniques, observing the temperature during and after the procedure. Methodology: Forty-five lower premolars were selected, prepared and randomly divided to be filled by the three techniques: lateral condensation (LC), single cone technique (SCT) and injectable thermoplasticized technique (IT). After preparation, the teeth were placed in a support built for this purpose and connected to the thermocouple. For thermographic analysis, the FLIR Tool T650sc Infrared thermal camera was used, adapted to 30 cm from the sample, minimum distance to maintain resolution. The thermography laboratory was maintained under controlled conditions of temperature and humidity, and the analyzes were carried out in an insulating box made of polystyrene wrapped in EVA. The temperature recordings were made from the thermographic camera and thermocouple viewfinder and the temperatures collected were the initial and after 30, 60, 90, 120 and 150 seconds after obturation. The data were statistically analyzed using the SPSS v21.0 program and different tests were used to prove the relationship between the variables Filling Technique x Anatomical Region x Time. Results: In the thermocouple, the temperature only increased significantly in the intervals in the SCT in the cervical third, unlike the IT and LC. Regarding the analysis of the thermographic camera, significant changes were observed between time and obturation technique and time and anatomical region. This difference was observed in the three techniques, mainly in the cervical and middle thirds. In LC and IT, an increase in temperature was observed 30 seconds after obturation, followed by a gradual decline, up to 150 seconds, with values close to the initial temperature. The SCT also showed an increase in temperature with 30 seconds, but the values returned to normal after 60 seconds in the apical third and after 90 seconds in the middle and cervical thirds. In all techniques, the temperature did not rise above the critical limit of 10°C. Conclusion: Every filling technique increased root temperature, and this increase being more evident in the IT technique, followed by LC and SCT. Although this increase occurs, the variation is small, and the temperature quickly returns to values close to normal. Keywords: Endodontics; changes in body temperature; root canal filling; thermography