Abstract
We tested the application of power spectral analysis of the heart rate fluctuation in order to investigate the transition of the autonomic nervous system activity during dental practice in 63 healthy children,5 healthy adults,22 children with congenital heart diseases (CHD) and 15 children with mental retardation (MR).
Electrocardiogram QRS wave forms were recorded on a multichannel FM tape and the R-R intervals were analyzed by the maximum entropy method (MEM), which was one of the methods of power spectral analysis. Consequently, we observed an apparent low frequency peak (LEP: 0.04-0.1 Hz) and a high frequency peak (HFP: 0.2-0.4 Hz), and those peaks varied from pre- to post-local infiltration ansthesia. In healthy and CHD subjects at 3 years of age, those variable patterns of the spectral peaks showed predominantly sympathetic hypertonic patterns, in which only LFP showed, but autonomic stable patterns, in which HFP was shown to be stable, increased more as the children became older. On the other hand, in the MR subjects, even though they were from 7 to 13 years old, no autonomic stable patterns showed, and those patterns were predominantly sympathetic hypertronic patterns as well as those in healthy and CHD subjects at 3years of age.
These results suggested that variable patterns of the R-R interval spectra with local infiltration anesthesia reflects the development of the autonomic nervous system and the maturation of the emotion, and concomitantly that power spectral analysis of the heart rate fluctuation was useful for evaluation of autonomic nervous system activity during dental practice.
