It is extremely important to prevent orthodontic and pedodontic patients from contracting caries. Although recently excellent progress has been made in the field of orthodontic and pedodontic materials, it is a common practice to use commercially marketed cement to fix the band of the orthodontic appliance and the crown etc during pedodontic treatment. Orthodontists are faced with the problem that tooth caties are caused by the orthodontic appliance itself, and pedodontists appear to have the same problem.
This study was undertaken in order to increase the hardness against the effects of crushing during mastication and to prevent the teeth from contracting dental caries. This report concerns the reaction of hydrotalcite on dental cement. Hydrotalcite has many different kinds of mineral substances, such as Mg_4⋅5Al₂(OH)₁₃CO₃⋅3.5H₂O. Hydrotalcite solidifies only when used with “Unident”, which is commercially available The mixture (esulted in twice the hardness compare with other kinds of dental cement. The Raman spectra of all the specimens were recorded with a JASCO Model R-800 laser-Raman spectrophotometer. The refection profiles of all the specimens changed according to the volume of hydro talcite contained in dental cement.

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The purpose of this study was to clarify the psychological factors concerning maladaptive behavior shown by children when they were given dental treatment.
With respect to adaptation to cavity preparation,42 children aged from 4to 8 years were classified into two groups -the adaptation group and the maladaptation group.
The personality of the child and the manner of the parents in bringing up the child were compared in the two groups. The results are summarized as follows:
1. The maladaptation group showed poor characteristics with respect to all items except “emotional stability” compared with the adaptation group.
2. A close relationship was found between maladaptive behavior with respect to dental treatment and personal characteristics such as “independence”, “adaptation to school” and “social stability”.
3. The maladaptation group showed a poor attitude of the parents toward the upbringing of the child, especially with respect to the relationship between the child and the mother compared with the adaptation group. However, it was in the “contradiction” category that concerning the relationship between the child and the father there was found a poor attitude with respect the upbringing of the child in the adaptation group compared with the maladaptation group.
4. The attitude of the mother towards upbringing which related to dental treatment was found “contradiction”.

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A boy,6 years and 11 months old, was diagnosed as having partial anodontia accompanied by congenital ectodermal dysplasia, and the following findings were obtained.
1. Systemic symptoms including hypohidrosis, protuberant lips, atrophic rhinitis, and atopic dermatitis were observed.
2.A total of 15 teeth consisting of 5 deciduous teeth, _??_, and 10 permanent teeth, _??_, were congenitally absent.
3.Concerning oral cavity findings,malformed crowns were observed in _??_and _??_.
4. Retarded eruption and retarded root growth of the permanent teeth were observed.
5. Growth of the alveolar bone was poor in the area where the teeth were absent.
6. Although the upper part of the face was underdeveloped, growth of the mandible was nearly normal. The extent of the growth of both the maxilla and the mandible was below standard.

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There exists a considerable literature on submerged deciduous teeth and congenital missing permanent teeth, but little work has been down to study the histologic features based on ground sections. Persistence of submerged _??_ with marked ankylosis was found in an 18-year-o1d male,and defects with respect to his succedaneous permanent teeth were discovered upon X-ray examination. After the extraction of those deciduous teeth, ground sections with non-decalcification were made for histologic study. The results were as follows:
1. Although succedaneous permanent teeth were defective, marked resorption of the roots of persistent deciduous teeth was noted, and the alveolar bone was poorly developed at those areas.
2. Some of the roots of the persistent deciduous teeth were replaced completely by bone tissues. These bone tissues were lamellar bones.
3. The dentin and newly formed bone tissue were in direct contact, and there were no connective tissues between them.
4. Tiny islands of bone tissue were found scattered in the dentin, and the residues of dentin fragments were found in the bone tissue.
5. Odontoclasts were not found on the resorpted surface of the dentin, and this finding suggested morphologically that a non-odontoclast-mediated mechanism also participated in the dentin resorption.

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The purpose of this study was to obtain the clinical results concerning the use of two types of the new composite resin, Clearfil Bond System Type-F and Type-SC. The cavity preparation and the restoration were performed on a total of 497 primary teeth (239 anterior teeth and 258 molars) of 102 Japanese boys and 91 Japanese girls. Type-F was used in 328 cases and Type-SC in 169 cases.
The observation period lasted up to 3 years and 3 months at the longest. The marginal state (discoloration, leakage, breakage and secondary caries)and the general state (discoloration, wearing-off and breakage or falling-off) of the filling material, spontaneous or/and thermal pain of the pulp, and the inflammation of the gingiva were evaluated. The evaluation was classified into three groups - 1) “satisfactory” (no specific clinical findings),2) “poor”, and 3) “breakage”(the partial or entire falling-of of the filling material).
The results were as follows:
1. Type-F was found “satisfactory” in 237 cases (72.2%), “poor” in 32 (9.8%)and “breakage” in 59 (18.0%). Type-SC was found “satisfactory” in 141cases (83.4%), “poor” in 18 (10.7%), and “breakage” in 10 (5.9%). Type-SC was evaluated as being slightly better, especially against breakage, than Type-F.
2. Type-SC had a tendency to give better results than Type-F regardless of the restored surfaces of the tooth and the number of restored surfaces.
3. Regarding the margin of the cavity preparation, the bevel type revealed the best results with both Type-F and Type-SC.
4. The restorations under the gingival line were evaluated “poor” or “breakage”in many cases irrespective of the type used. This tendency was more obvious in Type-F.
5. The restorations without the pulp capping in Type-F were evaluated as “poor”or “breakage” in considerably fewer cases than the restrations with pulp capping.
6. Both Types showed scarcely any undesirable clinical findings.
7. Both Types revealed better results with molars than with anterior teeth. The tendency was more obvious in Type-F.
8. This study revealed that the bevel type of marginal preparation and cavity preparation above the gingival line can be recommended in order to obtain desirable clinical results using “Clearfil”.

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On the basis of the dental health examination of 799 infants (414 boys and 385 girls)at the age of 1 year and 6 months±2 weeks and the questionnaires to their mothers, factors contributing to the dental caries of the early period were sought. The oral examinations of infants included noting the incidence of dental caries, oral hygiene conditions, numbers of erupting teeth, pH value of Cariostat, height and weight. As for their mothers, the pH value of Cariostat was evaluated as well as the questionnaires concerning nursing methods, dietary habits, tooth brushing habits, and other technical dental phenomena which might be familiar to mothers.
Discriminant analysis was carried out by subjecting them to the second class of Hayashi's quantifying theory. Presence or absence of the dental caries in infants was chosen as an external criterion.
As a result, contributing factors which separated the infants with dental caries from the subject without caries at the age of 1 year and 6 months were found to be as follows: the oral hygiene factor, the developmental factor and the oral habit factor. It was suggested that these factors might be the most important item when oral hygiene instructions for the child are given at such an early period.

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Electrical resistance changes of 120 primary teeth in children from two to eleven years of age were measured and the variable endodontic treatments were selected based on the range of these values. The relationship between the method of treatment and the range of electric resistance of the remaining tooth substances was originally set up by Suzuki et al., and was modified in this report.
The results of one year prognosis of the above experiments were as follows:
1) 111 cases (94.9 %) showed satisfactory results and 6 cases showed poor results.
2) By measuring the electrical resistance changes, the overlooking of invisible pulp exposure was avoided and the thickness of the remaining dentine layer was clearly measured. Furthermore, the involvement of pathological changes in the pulp might be also predicted by the evaluation of electrical resistance changes before and after the removal of affected dentine.
3) The use of the electrical resistance in the diagnosis for carious region of primary tooth was proven to be a very effective method in the pedodontic clinic.

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This paper describes a very rare case of congenital aglossia diagnosed as a Hypoglossia-Hypoductylia Syndrome.
The etiology of this anomalie is not clear. However, the intrauterine environmental factors are considered to be more important than the genetical influences. The patient was a 3 year-2 month-old girl with complaints of congenital aglossia and rampant carious teeth who was referred to the Clinic of Pedodontics at Osaka University Dental School Hospital. An evaluation revealed a completely defective tongue, mandibular hypognatia, partial anodontia of permanent teeth, and a high arched palate. The severely retarded development of the mandibular arch did not allow occlusion with the maxillary arch.
Growth of the maxilla seemed to be influenced by the tongue defect. Anomalies of the limbs were not observed, but the patient had complications with a venticular septal defect of the heart and had been admitted for surgery when she was 1 year and 3 months old. She seemed to speak well, appeared intelligent, and adapted well to the prosthesis. In addition, she could distinguish various kinds of tastes.

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