[Correlations between masticatory performance in chewing gum method and occlusion as well as dento-facial morphology].

In order to examine the characteristics of the chewing gum masticatory test, the amount of sugar elution, the chewing time and the amount of sugar elution per second were measured in 109 young adults (93 males and 16 females), after 70 strokes of mastication. Their sex differences, differences among various occlusions, correlations with occlusal areas of the buccal teeth and correlations with roentgen cephalometrics were analyzed. 1. There was no sex difference in the amount of sugar elution. However, chewing time was shorter and the amount of sugar elution per second was higher in males than in females. 2. Compared with the normal occlusion group, the amount of sugar elution was significantly lower in the crowding and anterior cross bite groups (Inoue's classification), and in the Class III malocclusion group (Angle's classification) in males. The amount of sugar elution per second was also significantly lower in the crowding and anterior cross bite groups. However, significant differences could not be found for chewing time. 3. The amount of sugar elution per second was significantly correlated with occlusal areas in males and total samples. 4. The amount of sugar elution was significantly correlated with less than ANB and less than L 1 to MP in males, with less than L 1 to MP in total samples. The chewing time was significantly correlated with S-N, N-Me, N-ANS, S'-Ptm' in females. The amount of sugar elution per second was significantly correlated with less than SNA and less than L 1 to MP in males, and with A'-Ptm', Cd-Go, Go-Pog', Cd-Gn, less than SNA, less than L 1 to MP, less than MP-SN and gonial angle in total samples. 5. It is concluded that the chewing gum masticatory test is highly correlated with occlusion and dento-facial morphology. In particular, amount of sugar elution per second was thought to be a useful measure for masticatory performance in clinical orthodontics.