Analysis of Human Tooth Pulp Chamber Temperature After 670 nm Laser Irradiation: In Vitro Study

作者:Alves Carrara de Oliveir Cleide Regina; Zanin Fatima; Cassoni Alessandra; Rodrigues Jose Augusto; Silveira Landulfo Jr; Pacheco Marcos Tadeu; Brugnera Junior Aldo
来源:Photomedicine and Laser Surgery, 2017, 35(10): 515-519.
DOI:10.1089/pho.2016.4233

摘要

Objective: One of the limiting factors of employing laser radiation on dental therapies is the potential of causing thermal injuries to pulp tissues. The purpose of this study was to evaluate intra-chamber temperature increase on extracted human teeth exposed to 670 nm wavelength InGaAlP laser diode radiation. Materials and methods: In vitro intra-chamber temperature measurements of 12 standardized human teeth (incisors, canines, premolars, and molars; n = 3) were taken both before and after laser radiation. A type-K thermocouple fast-response thermocouple wire with a 0.5mm diameter probe was inserted into the tooth pulp chamber (ICEL-Manaus-brand). The laser device Lasotronic-brand InGaAlP laser diode was used to irradiate tooth enamel, perpendicularly to the external surface for 30 sec, with power of levels of 340, 272, 204, 136, and 68mW. The measurements were taken at three time points: 0, 30 sec, and 3min after the laser irradiation. Measurements were repeated 24 h after removal and reinsertion of the probe in the pulp chamber. The temperature gradient (Delta T in degrees C) was calculated (DT = final temperature-initial temperature) for each group. Data of DT were statistically analyzed by two-way analysis of variance (ANOVA) at the 95% confidence level and compared by Tukey post hoc test (alpha = 0.05). Results: ANOVA showed statistically significant differences to the interaction of factors (p < 0.05). The highest DT values obtained were observed to incisors with 340 mW, 272mW; 204mW of power (respectively 4.7 degrees C, 4.2 degrees C, and 3.1 degrees C); and canines presented the lowest DT (0.8 degrees C-0.3 degrees C) with no influence of power output. Conclusions: Since the thermal increase was observed in this study, especially in incisors, attention should be paid to avoid pulpal damage.

  • 出版日期2017-10