Simeone Michele, Santis Roberto De, Ametrano Gianluca, Prisco Davide, Borrelli Marino, Paduano Sergio, Riccitiello Francesco, Spagnuolo Gianrico
Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples Federico II, Naples, Italy.
Institute of Composite and Biomedical Materials, National Research Council of Italy, Naples, Italy.
Open Dent J. 2014 Dec 29;8:229-35. doi: 10.2174/1874210601408010229. eCollection 2014.
To evaluate temperature profiles developing in the root during warm compaction of gutta-percha with the heat sources System B and System MB Obtura (Analityc Technology, Redmond, WA, USA). Thirty extracted human incisor teeth were used. Root canals were cleaned and shaped by means of Protaper rotary files (Dentsply-Maillefer, Belgium), and imaging was performed by micro-CT (Skyscan 1072, Aartselaar, Belgium).
Teeth were instrumented with K-type thermocouples, and the roots were filled with thermoplastic gutta-percha. Vertical compaction was achieved through the heat sources System B and System MB, and temperature profiles were detect-ed by means of NI Dac Interface controlled by the LabView System. With both heat sources, higher temperature levels were recorded in the region of the root far from the apex. When the warm plugger tip was positioned at a distance of 3 mm from the root apex, temperature levels of about 180°C were used to soften gutta-percha, and no statistically significant differences were observed between peak temperatures developed by the two heating sources at the root apex. However, a temperature level higher than 40°C was maintained for a longer time with System MB.
Statistically significant differences were observed in peak temperature levels recorded far from the root apex. Thus, with a temperature of about 180°C and the warm plugger positioned at 3 mm from the root apex, both heating sources led to a temperature slightly higher than 40°C at the apex of the root, suggesting that the gutta-percha was properly softened.
A temperature level higher than 40°C was maintained for a longer time with System MB, thus providing an ad-equate time for warm compaction of the gutta-percha.
评估使用热牙胶充填系统B和系统MB Obtura（美国华盛顿州雷德蒙德市的Analytic Technology公司）对牙胶进行热压填胶时牙根内的温度变化情况。使用了30颗拔除的人上颌中切牙。根管采用Protaper旋转锉（比利时登士柏-迈勒费公司）进行清理和预备，并通过微型计算机断层扫描（比利时阿尔策拉尔市的Skyscan 1072）进行成像。
在牙齿上安装K型热电偶，牙根内充填热塑性牙胶。通过热牙胶充填系统B和系统MB进行垂直加压，温度变化情况通过由LabView系统控制的NI Dac接口进行检测。使用这两种热源时，在远离根尖的牙根区域记录到较高的温度水平。当热充填器尖端距离根尖3 mm时，约180°C的温度水平用于软化牙胶，两种加热源在根尖处产生的峰值温度之间未观察到统计学上的显著差异。然而，系统MB使高于40°C的温度水平维持的时间更长。
在远离根尖处记录到的峰值温度水平存在统计学上的显著差异。因此，当温度约为180°C且热充填器位于距根尖3 mm处时，两种加热源在根尖处均导致温度略高于40°C，这表明牙胶已被适当软化。
系统MB使高于40°C的温度水平维持的时间更长，从而为牙胶的热压填胶提供了足够的时间。
