Temperature Changes Along a Dental Implant

Purpose: The aims of this in vitro study were to analyze temperature changes along the surface of a dental implant and to establish the abutment temperature that could cause the critical 47°C/1 min threshold at the implant level. Materials and Methods: Eight thermocouples were attached at 1-mm intervals to an abutment/implant configuration. The model consisted of two compartments in a thermostatically controlled environment. The upper compartment represented the oral cavity with the abutment, which was exposed to 20 mL of hot water. The temperature at each thermocouple was logged over a period of 10 minutes. The Spearman rank correlation test and logistic regression model were used for the statistical analysis of the time/temperature databases and the estimation of the "effective dose 50" (ED50) for the abutment (95% confidence interval). Results: For 53 test series, the abutment temperature ranged from 52.80°C to 71.72°C. There was a positive correlation between the maximum temperature at the implant level and the temperature of the abutment. The 47°C/1 min threshold was reached 31 times at the most cervical implant level and decreased in frequency farther away from the heat source (14, 6, 3, 1, and 1 times, respectively). The ED50 was estimated at 62.3°C. This means that for an abutment temperature of 62.3°C, there was a 50% chance that 47°C would be reached at the implant level for 1 minute. Conclusion: This in vitro study supports the hypothesis that abutment temperature is transmitted to an implant. Although results of in vitro studies should be interpreted with caution, clinicians should be aware of temperature changes along implants and the potential risks associated with them.