Baldissara P, Bortolini S, Papale G, Scotti R
Sezione di Clinica Odontoiatrica, Università degli Studi, Ferrara.
Minerva Stomatol. 1998 Sep;47(9):373-80.
Various dental procedures can generate thermal increase in the dental pulp, in particular if they are incorrectly conducted. In literature the pulp cells are considered very heat sensitive. In this study the symptomatological response of patients during and after thermal administration to the dental crown has been recorded. The analysis of the symptomatology was used as an indication for the definition of the threshold of thermal damage.
Twelve healthy teeth of four patients programmed for extraction were subdivided into six couples of homologous teeth. One tooth out of each couple was used for the immediate in vivo recording of the symptoms; the other, once extracted, was used to determine the thermal increase applied through the insertion of a thermocouple sensor. In each couple of teeth the thermal stimulus was equal.
The average thermal increase was 11.2 degrees C. Pain starts at temperatures ranging from 39.5 to 50.4 degrees C with an average of 44.6 degrees C. This agrees with classical physiological data which reports the threshold of pain at 45 degrees C.
The threshold of pain registered suggests that at temperatures below 44.6 degrees C damage to the dental pulp is improbable, at least in healthy teeth. The limit of 45 degrees C appears, therefore, to be a probable safe threshold, contrary to what is reported in literature.
各种牙科手术会使牙髓温度升高，尤其是操作不当的时候。文献中认为牙髓细胞对热非常敏感。在本研究中，记录了患者在对牙冠进行热刺激期间及之后的症状反应。症状分析被用作确定热损伤阈值的指标。
将计划拔牙的4名患者的12颗健康牙齿分成6对同源牙。每对中的一颗牙用于即时记录体内症状；另一颗牙在拔除后，用于通过插入热电偶传感器来确定施加的温度升高。每对牙齿的热刺激相同。
平均温度升高为11.2摄氏度。疼痛始于39.5至50.4摄氏度，平均为44.6摄氏度。这与经典生理学数据相符，该数据报告疼痛阈值为45摄氏度。
记录的疼痛阈值表明，至少在健康牙齿中，温度低于44.6摄氏度时牙髓不太可能受损。因此，45摄氏度的限度似乎是一个可能的安全阈值，这与文献报道的情况相反。
