[Study on the feeding function and feeding behavior of children. 1. Biting pressure and masticatory efficiency for 3, 4 and 5 years old children].

The purpose of this study was to investigate the biting pressure and masticatory efficiency of 3, 4 and 5 year old children. Some of them had trouble regarding their feeding behavior, either saying that they were not able to bite hard food or that they didn't want to bite hard food. A new method using A.T.P. (Adenosine Triphosphate) granules introduced with rubber finger protectors was used for measurement of the masticatory efficiency. 69 healthy 3, 4 and 5 year old children who had normal occlusion and were caries free were the subject. The results obtained were as follows. 1) The mean of the biting pressure for the 2nd primary molars for 69 children was 21.7 Kg. As for the data of the biting pressure for each age group, it was shown to increase with age (3 to 5 year old). 2) The mean of the masticatory efficiency for 69 children was 0.201 abs. As for the data of the masticatory efficiency for each age, it were shown to increase with age (3 to 5 year old). 3) The coefficient of the correlation of the biting pressure and the masticatory efficiency for 69 children was 0.410 which was considered statistically significant. (P less than 0.05) The coefficient of the correlation of the biting pressure and the masticatory efficiency for 3 year old children was 0.461, the coefficient of the correlation for the same items for 4 year old children was 0.395 and the coefficient of the correlation for 5 year old children was 0.353. All of these were considered statistically significant. (P less than 0.05)