The purpose of this study was to investigate the influence of inhalation sedation using 30% nitrous oxide/70% oxygen on the change of the urinary catecholamine level in children during dental treatment. The subjects were 50 healthy children aged from 4 to 9, who received dental treatment with cooperative behavior during all procedures under inhalation sedation (sedation group) or non-sedation (non-sedation group). The sedation group consisted of 17 children, and the non-sedation group of 33children. For the purpose of analysis, each group was divided into two age groups; the younger group was composed of children aged from 4 to 6, and elder group was composed of children aged from 7 to 9. They received dental treatment, including infiltration anesthesia using 3% Citanest-Octapressin (without epinephrine), rubber-dams, cavity preparation and restoration.
The urine samples analyzed were collected before and after the dental treatment. Dopamine, noradrenaline and adrenaline were isolated from the urine and quantitative analyses were performed. The ratios of the post-treatment catecholamine levels for the pre-treatment catecholamine levels were calculated as the conversion ratio. The results were summarized as follows; In the younger children of the non-sedation group, the adrenaline, noradrenaline, and dopamine concentrations taken post-treatment were significantly higher than those taken pre-treatment. In the younger children of the sedation group, the adrenaline concentration taken post-treatment was significantly higher than that taken pre-treatment.
In the elder children of the non-sedation group, the adrenaline concentration taken post-treatment was significantly higher than that of pre-treatment. In the elder children of the sedation group, however, there were no significant differences between the concentrations of all indications taken pretreatment and taken post-treatment.
The conversion ratios of the dopamine, noradrenaline and adrenaline of the non-sedation group were significantly higher than those of the sedation group in both age groups. There were, in particular, statistical significant differences among the all of the indications of the younger children.
These results showed that catecholamine synthesis during dental treatment in children is depressed with inhalation sedation of nitrous oxide/oxygen. This tendency is more significant in younger than elder children.