The mineralization values in the body of the artificially-demineralized caries-like lesion of human enamel, embedded with and without polyester resin, were analyzed on the transverse polished surfaces of 5 premolar teeth by energy-dispersive X-ray microanalysis (EDX) in SEM. In addition, the caries-like lesions were observed by backscattered electron (BSE) imaging and analyzed by wavelength-dispersive X-ray microanalysis (WDX). The resin-free samples had the caries-like body showing high BSE signals when compared with the rein-embedded samples. The high BSE-signal image will be caused by the ridges of the relatively-remineralized prism peripheries and the pits of the markedly-demineralized prism cores under mechanical grinding. The WDX line-profile of Ca-Kα in the resin-free samples was markedly decreased in the caries-like body when compared with that of the resin-embedded samples. The lower Ca content may be caused by the hollow of the caries-like body under mechanical grinding. In SEM-EDX, the caries-like body of the resin-free samples showed higher Ca values and tended to show higher P values than that of the resin-embedded samples. Such EDX data of the resin-free samples will be caused by porous structures in the caries-like body. In conclusion, when analyzed the natural caries and artificial caries-like lesions of enamel by SEM-EDX and WDX and also observed them by BSE, the samples should be embedded in infiltration resin in order to fill the porous structures and to form the smooth polished plane.
The orthodontic diagnosis in growing patients requires appropriate predictions of their future craniofacial morphology. The purpose of this study was to obtain basic information about skeletal Class III malocclusion, with body mass index (BMI), which is well correlated with amount of body fat, and to investigate the possibility of clinical application of this information. The subjects, referred to as Class III group, included 105 males (mean age, 25.2±1.8 years; range, 15-38 years) and about 166 females (mean age, 24.9±1.9 years; range, 15-36 years) who presented with skeletal Class III malocclusion diagnosed as needing surgical orthodontic treatment. Data on the control group as normal Japanese population were obtained from the 1997 “Statistical Report on the School Health Survey” presented by the Ministry of Education, Japan, and 1998 “National Nutrition Survey” presented by the Ministry of Health and Welfare, Japan. That data included parameters such as growth phase of the whole body, BMI, height, and body weight. The results were as follows : 1. Class III group male in their twenties and thirties, and Class III group female in their thirties showed significantly lower BMI than the BMI of the control group. More specifically, this tendency was most pronounced on males in their twenties. 2. The frequencies of obese and non-obese cases, respectively, were obtained. Class III group had lower frequencies of obesity, and tended to have a higher frequency of non-obesity, in all age subgroups of males and females in comparison with the control group. 3. In a comparison of the annual changes in BMI in subjects from the ages of 6 to 17 between Class III group and the control group, subjects in Class III group tended to have lower BMI. This tendency was stronger in males than in females. The greatest difference between Class III group and the control group was found in male and female subjects at the ages of 11 and 8, respectively. 4. Class III group was subdivided into non-obese and obese subgroups according to BMI, and the craniofacial morphology was compared between these two subgroups, using lateral cephalometric radiographs. The female obese subgroup showed a mandibular corpus length (POG'-GO) significantly shorter than that in females in the non-obese subgroup. These results indicated that the BMI reflected growth phase in Class III group more accurately than did height and body weight. Based on the relationship between amount of fat tissue and craniofacial morphology clarified in this study, it is considered that more detailed studies on the presence of fat tissue will further our understanding of growth phase in the craniofacial region, which will be useful for orthodontic practice.