Effect of preheated bulk‐fill composite temperature on intrapulpal temperature increase in vitro

Abstract

Objectives The aim of study is measurement of in vitro intrapulpal temperature increase when placing room temperature or preheated (54°C and 60°C) bulk‐fill composite. Materials and methods Extracted human lower third molars were selected and class II (MOD) cavities in each tooth were prepared, resulting in a remaining dentin thickness of 1 mm. A K‐type thermocouple was placed inside the pulp chamber. Teeth were placed in a 37°C bath, which simulated human body temperature. Teeth were restored with a bulk‐fill composite that was stored at room temperature and preheated at 54°C and 60°C. Data were subjected to two‐factor mixed‐design analysis of variance using a general linear model procedure for repeated measurements. Results Stage, composite temperature, and stage‐composite temperature interaction significantly affected the intrapulpal temperature values (P < .001). Conclusions Preheating does not represent significant problems in terms of intrapulpal temperature increase. Even Though the preheating process results in an increase in intrapulpal temperature, this temperature increase is not the critical factor that causes harm to the pulp. Clinical Significance Preheating can improve material features. Benefits of improved material features are desirable to practitioners. Temperature increase is not the critical factor that harms to the pulp even if the preheating process can result with an increase in intrapulpal temperature.

Evaluation of heated air jet on pulp chamber temperature at different steps of the restorative protocol

“…However, there are still a few numbers of studies that have successfully determined the possibility of pulp aggression. Thus, in this investigation, the evaporation of solvents in a universal adhesive system using a heated air jet showed promising results, with regard to maintaining the pulp tissue temperature in the safe range (Pohto & Sheinin, 1958;Zach & Cohen, 1965;Baldi, et al, 2019;Karacan & Ozyurt, 2019) even in the very deep cavity.…”

“…It is well-known that if the critical pulp heating threshold is reached or exceeded, the resulting changes can lead to a variety of problems including irreversible pulpitis to pulp necrosis (Zach & Cohen, 1965;Baldi, et al, 2019;Karacan & Ozyurt, 2019;Nilsen, et al, 2020). In this context, it has been established that the smaller the dentin thickness remaining in a cavity preparation, the greater the proximity to the dental pulp; consequently, this increases the chances of aggressive agents in the dentin to reach the odontoblast extensions (Kwon, et al, 2013;Vinall, et al, 2017;Yasa, et al, 2017;Akarsu & Aktuğ Karademir, 2019).…”

“…However, studies show that the variation capable of altering the pulp tissue is 5.5 ºC above the average temperature of the oral cavity that varies from 36.2 to 37ºC °C (Zach & Cohen, 1965;Baldi, et al, 2019;Karacan & Ozyurt, 2019;Nilsen, et al, 2020), with 42-42.5°C being the average critical pulp temperature to initiate irreversible damage (Pohto & Scheinin, 1958).…”

“…In addition to the advantages mentioned, this composite was photoactivated for only 20 s, following the manufacturer's recommendation; this is because the photoactivator had an intensity exceeding 1000 mW / cm 2 (Campodonico, et al, 2011;Yarmohammad, et al, 2019), which may also have contributed to the maintenance of the pulp temperature at the safe threshold of variation (Zach & Cohen, 1965;Baldi, et al, 2019;Karacan & Ozyurt, 2019;Nilsen, et al, 2020).…”

“…In this study, an air jet was used to volatilize the solvents present in the Universal Single Bond adhesive system under two distinct temperatures, 23 or 40 °C, whose maximum temperature did not even reach 38 °C; this was observed regardless of the group in question, remaining in a safe variation zone (Pohto & Sheinin, 1958;Zach & Cohen, 1965;Baldi, et al, 2019;Karacan & Ozyurt, 2019).…”