A Study of Temperature Rise in the Pulp Chamber during Composite Polymerization with Different Light-curing Units

Abstract

Aim:The study compared pulp temperature rise during polymerization of resin-based composites (RBCs) using halogen and LED light-curing units (LCUs). Methods and Materials:A total of 32 teeth extracted from patients aged 11-18 years were used in the study. Thermocouples placed on the roof of the pulp chamber using a novel 'split-tooth' method. In Group 1 a halogen LCU with a light intensity of 450 mWcm -2 was used and in Group 2, an LED LCU with a light intensity of 1100 mWcm -2 was used. The teeth were placed in a water bath with the temperature regulated until both the pulp temperature and the ambient temperature were stable at 37ºC. Continuous temperature records were made via a data logger and computer. The increase in temperature from baseline to maximum was calculated for each specimen during the curing of both the bonding agent and the RBC. Results:The rise in pulp temperature was significantly higher with the LED LCU than with the halogen LCU for bonding and RBC curing (p<0.05). The major rise in temperature occured during the curing of the bonding agent. During the curing of the RBC, rises were smaller. Conclusions:Curing of bonding agents should be done with low intensity light and high intensity used only for curing RBC regardless of whether LED or halogen LCUs are used. Abstract© Seer Publishing

Analysis of laser transmission and thermal effects on the inner root surface during periodontal treatment with a 940-nm diode laser in anin vitropocket model

“…24,25 One or two TCs are commonly placed inside the pulp chamber or the root canal of intact teeth to detect pulp temperature, 25,26 even though several limitations like an unexact positioning of the TCs, the influence of different RDTs on temperature rise, nonreal-time measurements at different positions, and a possible gap between TC and dentine, probably lead to measurement errors. 30,31 Biological variation was minimized by removing the crowns and apices. 28,29 Although these modifications in geometry and mass have an influence on heat conduction 27 and heat capacity, no significant differences in the temperature rise between split teeth and intact teeth have been reported in the literature.…”

Direct measurement of time-dependent anesthetized in vivo human pulp temperature

“…Thus, the first hypothesis was accepted. In this regard, consistent baseline, plateau temperature values were observed, having a very low standard deviation (±0.7 • C), with a confidence interval ranging from 35.0 to 35.7 • C. In contrast to the assumption that anesthetized human pulp has the same temperature as the human body core (approximately 37 • C) [5,7], lower temperature values (35.3 • C ± 0.7 • ) with a temperature range lower than that observed in the axilla: 36.2 to 37.5 • C [15] were observed within the pulp, after 25 min of stabilization. Thus, the second research hypothesis was rejected.…”

“…In that study, a 5.5 • C PT increase in rhesus monkeys, from application of a hot metal source to the facial enamel surface, induced necrosis in 15% of evaluated pulps. Because of the high expense of animal testing, in vitro techniques using extracted teeth were developed to evaluate pulp chamber temperature change under simulated clinical conditions, while applying various external heat sources [5,7,8]. In these reports, the pulp chamber temperature, prior to application of temperature-raising effects, was pre-set at 37 • C (human body temperature) [5,7,9], or at room temperature [4], or was not mentioned in the study [10,11].…”

“…Because of the high expense of animal testing, in vitro techniques using extracted teeth were developed to evaluate pulp chamber temperature change under simulated clinical conditions, while applying various external heat sources [5,7,8]. In these reports, the pulp chamber temperature, prior to application of temperature-raising effects, was pre-set at 37 • C (human body temperature) [5,7,9], or at room temperature [4], or was not mentioned in the study [10,11]. Others simulated the influence of pulpal blood flow in vitro, to evaluate how this parameter might dissipate internal tooth heat generated by exposure to dental light curing units [5,12,13].…”

Alteração de temperatura na dentina durante o procedimento restaurador com resina composta variando as fontes fotopolimerizadoras

“…Contudo, outros fatores devem ser considerados, tais como o comprimento de onda do equipamento e o tipo de matriz da resina composta. Tendo em vista a complexidade da avaliação da temperatura, outros estudos seriam necessários para complementar as informações obtidas neste trabalho, uma vez que a extensão da lesão térmica que pode ser tolerada pela polpa dentária é desconhecida (BALDISSARA et al, 1997, STEWARDSON et al, 2004MILLEN et al, 2007). De acordo com os resultados obtidos, foi possível concluir que:…”