2013 Volume 56 Issue 1 Pages 55-62
Purpose: Dental caries detection has been traditionally performed through visual inspection and radiographic methods. However, these diagnostic methods are subjective and have been shown to vary greatly among dentists. Due to these limitations, new quantitative technologies have been proposed to help dentists assess carious lesions. The aim of this study was to compare the performance of optical fiber or ion-sensitive field effect transistor (ISFET) micro pH sensor with a pen-type laser fluorescence device (DIAGNOdent pen) for assessing the activity of natural enamel and dentinal lesions in vitro. Methods: Thirty lesions on extracted carious teeth were divided into three groups, initial enamel caries, active dentinal caries and arrested dental caries, according to the predefined clinical criteria. The surface pH value of each caries sample was recorded by two micro pH sensors: optical fiber or ISFET. The laser fluorescence signal value was also measured by a pen-type laser fluorescence device. The results were analyzed using the Wilcoxon rank sum test within devices and Spearman's rho tests between them. Statistical significance in all analyses was set in advance at a probability level of 0.05. Results: For the optical fiber pH micro sensor, the mean pH values of the carious lesions were 5.7±0.3 (active), 6.2±0.2 (arrested) and 6.2±0.1 (initial). For the ISFET pH micro sensor, the mean pH values were 5.5±0.3 (active), 6.1±0.3 (arrested) and 6.2±0.2 (initial). For these techniques, statistically significant differences were observed in the measured pH values between active and arrested dentinal caries (p<0.05). On the other hand, for the pen-type laser fluorescence device, the mean laser fluorescence values of the lesions were 99.0±0.0 (active), 83.1±19.2 (arrested) and 33.0±20.4 (initial). For this technique, statistically significant differences in the mean signal values were observed between arrested dentinal caries and initial enamel caries (p<0.05). For all techniques, statistically significant differences in measurement values were observed between active dentinal caries and initial enamel caries (p<0.05). In addition, positive relations between the two pH measurement methods were found, and negative relations were found between the pen-type laser fluorescence device and optical fiber pH micro sensor, and between the pen-type laser fluorescence device and ISFET pH micro sensor (p<0.05). Conclusion: Based on the results of three measurements, all techniques showed usefulness for distinguishing caries activity between active dentinal caries and initial enamel caries. Furthermore, positive relations between the two pH measurement methods were found.
