Dentinogenesis imperfecta (DI) is an inherited disorder of the dentin formation. Although the clinical and histological characteristics of the disease have been described in many reports, the pathogenesis has not been clarified.
In the present study, deciduous teeth obtained from normal individuals and four patients with dentinogenesis imperfecta were examined using newly developed histochemical methods for detection of dentin phosphoprotein. There was distinct phosphoprotein staining in the normal dentin except in the mantle dentin and in the reparative dentin, but not in the DI dentin. In addition, there were lines or granular layers, which were obviously different from both the contour lines of Owen and the granular layer of Thomes, in the external portion of the DI dentin. These may result from disturbance of the dentin formation after the initial tissue deposition.
On the basis of these results, we propose as a hypothetic interpretation of the pathogenesis of the disease that the life span of the primary odontoblasts may be severely curtailed, and the dentin formation after the degeneration of these cells may be accomplished by the immature cells of pulpal origin.

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The purpose of this report was to search for the clinical requirements in regard to the TMJ dysfunction syndrome in adolescents. The subjects which we examinated by means of questionnaires were 2198 children aged 10-18 years (1095 boys and 1103 girls). Also we compared each subjective evaluation with the frequency of occurrance and based on objective examination of each subject, we investigated the significance of the case.
The results obtained were as follows:
1. Subjective incidence of this syndrome involced 253 children (11.5%)-129boys (11.8%) and 124 girls (8.2%)-with no significant differences being found between boys and girls.
2. From individual comparisons based on the clinical examinations, the junior high school age was found to be the proper age for the beginning of preventive medical care, because they were as aware of the symptoms of the TMJ dysfunction syndrome, as were the adults, and were aware of them precisely. Also the TMJ sounds were suggested as a key for guidance.
3. From the results of the frequency of questionnaire, the frequency of the clinical examinations and the“awareness”, we obtained data thought to show why females showed a high frequency in the clinico-statistical study.

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The present study was undertaken to survey the relationship between the Tooth-to-Denture-Base Discrepancy and dental disease in 144 junior high school boys and girls aged 14 to 15 years. Tooth-to-Denture-Base Discrepancy was evaluated quantitatively based on the Total Discrepancy (TD) which consisted of the Arch Length Discrepancy(ALD)for the degree of crowding and Head Plate Correction (HPC) for the labial inclination of lower anterior teeth using Tweed's method.
No difference based on sex was observed on TD and ALD. The mean value of TD was -2.70 and it was ranged from -21.5 to 16.3.
No statistical significant relationship between the experience of dental caries (DMFT) and TD was found, but there was a statistically significant correlation between DMFT in anterior teeth and ALD.
In the statistical analysis of the relationship between periodontal disease by Russell's Periodontal Index (P. I. ) and discrepancy, a weak negative correlation (r=-0.19, p<0.05) between P. I. in the lower jaw and TD was found, but there was no significant correlation between P. I. and ALD.
Therefore, it is suggested that factors other than discrepancy had influenced the incidence of dental caries and periodontal disease in these junior high school children.

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One hundred and forty-six handicapped children living in institutions were investigated for their behavior concerning tooth brushing, the condition of their oral hygiene and their level of development.
The obtained results were as follows;
1. The teeth of each child were brushed daily, although 93.2 % of them required some assistance or care by the institution staff or their parents.
2. For 67.8% of the children, the condition of their oral hygiene was evaluated good or fair. This favorable situation seemed to due to the positive care by the staff and the parents.
3. A high correlation was recognized between the behavior of brushing and the developmental levels in every field. The highest one was found in the field of the basic daily habits of the mentally retarded and the autistic children, and in the language of the dual handicapped who had mental retardation and physical disability.
4. It seemed that, when the mentally retarded or the autistic child showed abilities higher than those of the three and half year old age level in the developmental age for the basic daily habits, they would be able to handle a tooth brush, and when exceeding the four year level, they could be expected to clean their teeth by themselves.
5. In the child with dual handicapes, when they showed language abilities of more than a two year old age level, they would be able to see the meaning of brushing; and when exceeding the three and half year old age level, they could be expected to handle the tooth brush in response to an order.
6. A certain readiness should be considered as an important factor when giving instruction in tooth brushing.

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An eight-year-old boy visited the Clinic of Neurosurgery, Kobe Children's Hospital, with a plain skull film after an injury to his head which showed a calcification shadow in the cranium. The patient on the basis of the results of several examinations was diagnosed as having intracranial teratoma. The teratoma was not excised because of its location which made excision impossible. Since the brain pressure was eventually eleviated, a V-P shunt operation was conducted to obtain a depressive effect.
The patient, however, thereafter showed gradual deterioration, and died in a vegetable a state at the age of 11 years 9 months.
Autopsy findings included attachment of the teratoma to the floor of the third ventricle. The removed tumor weighed 40 gms. By macroscopic appearance, cysts, teeth and bone fragments were noted. Microscopic examination of the tumor revealed it consisted of a variety of solid tissues-including teethand cysts of various size.

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A true primary supernumerary tooth was found in a girl 18 months old.
1. The occurrence in the mandibular incisal region as the site was rare.
2. Similarity in the degree of radiopacity was suggested to be an important criterion in making the diagnosis as a primary supernumerary tooth.
3. On the basis of intraoral findings, radiological findings, and analysis of the plaster cast, the primary central incisor on the mesial side was concluded to be the primary supernumerary tooth.
4. A decision was made to make a follow-up observation for handling the tooth. It was also decided to give at each regular examination oral hygiene guidance and denture guidance.

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Besides information concerning the metabolism of sucrose and its content in food, it is also of high relevancy the relationship between the content of sucrose and the development of dental cavities.
We investigated the content of sucrose in different pharmaceutical syrups, since it is hardly known whether they contain sucrose or not.
The results were as follows:
1. The majority of the drugs studied contained more than 800 mg of sucrose per gram of medicine.
2. About 88% of those who answered the questionnaire had experienced rejection of the drugs and,50% of them said they could take the drugs after maskarading the taste of the drugs by mixing them with juice or drinking juice immediately after taking the drugs.
3. Only about 35% said they had brushed their teeth or rinsed their mouths after taking the drugs. However, the purposed of this was to wash away the taste of the drug and not as an oral hygiene measure. From the results presented above we conclude that attention must be paid when prescribing pharmaceutical syrups. First, because of the possibility of inducing bad feeding habits in children, since taking pharmaceutical syrups is similar to having sweetmeats. Second, because of the role of sucrose in the development of dental cavities.
Taking these facts into consideration, children and parents must be informed about the importance of oral hygiene after taking pharmaceutical syrups.

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In 1954, Menkes first described a metabilic obstruction of a herediatry nature caused by leucine, isoleucine and valine branching amino acid, which is now generally accepted as the Maple Syrup Urine Disease.
There are no reports of oral involvement regarding this disease.
The patient, a 5 year 4 month old girl, diagosed as having the Maple Syrup Urine Disease at the Department of Pediatrics Clinic, Kagoshima University School of Medicine, was referred to the Pedodontic Clinic, Kagoshima University School of Dentistry.
The results were as follows:
1) In findings of the dental arch cast, the length and width of the dental arch were found to be small in size.
2) Susceptibility to dental arch caries was more serious than normal child due to her bad eating habits, poor dental health care and ebur dentis.
3) If their systemic condition is kept under control, we can consider patients with the Maple Syrup Urine Disease as a normal child.

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A 5 year and 2 month old boy was referred to the Department of Pedodontics, Asahi University, School of Dentistry, with a chief complaint of swelling and tenderness at the left buccal gingiva of the mandibular primary molar region. Through radiographic examination and his anamnesis, the patient was diagnosed clinically as having a dentigerous cyst. The findings, based on the pathological examination, however, showed fibrous stroma with proliferating odontogenic epithelial remains in the cyst wall and odontogenic epithelium penetrating into the stroma.
Consequently the patient was diagnosed as having cystic ameloblastoma. Therefore, the present case strongly suggested that whenever a dentigerous cyst is encountered clinically, pathological examination on the biopsy should be carried out for differential diagnosis of ameloblastoma and dentigerous cyst, since the treatment and prognosis between them are quite different.
The differential diagnosis of ameloblastoma and dentigerous cyst should be confirmed by histological examination.

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We studied clinically and radiographically the effects of Vitapex as a root canal treatment on deciduous teeth. Eighty-eight teeth were examined,21 of them pulpectomized teeth and 67 infected root canal treated teeth.
These teeth were observed until either the time of the extraction of the teeth with the lesion or the time of the eruption of their successors.
The results were as follows;
1. For the infected root canal treated teeth, the period of observation was 8months to 4 years 9 months for the anterior teeth and 7 months to 6 years 3 months with the posterior teeth. For the pulpectomized teeth, the period of observation was 8 months to 4 years 9 months for the anterior teeth and 2years 6 months to 5 years 11 months for the posterior teeth.
2. The rate of success in root canal filling was 80% for the pulpectomized anterior teeth and 73.6% for the root canal infected anterior teeth. Similary to the anterior teeth, the success rate in root canal filling was 81.8%for the pulpectomized posterior teeth and 79% for the root canal infected posterior teeth.
3. Nineteen out of 88 root canal filled teeth were extracted,12 teeth were extracted due to the contamination of the root canal following the falling out of the restoration,6 teeth due to the abcess formation, and 1 tooth due to the ectopic eruption of the neighboring permanent tooth.
4. We studied the relationship between the success rate and the presence either of root absorption or inter-radiculor rarefaction. The success rate was higher when both interradicular rarefaction and the root absorption were smaller. In spite of the existance of inter-radicular rarefaction, the success rate was higher when root absorption was not observed. On the other hand, in spite of the presence of the root absorption, the success rate was higher when inter-radicular rarefaction was not observed.
5. Enamel hypoplasia of the successor (Turner's Teeth) was observed in 8 teeth out of 68. The rate of calcification of the turner's teeth when the deciduous teeth were root canal treated, was under score 3 of the Nolla classification.
6. There was no difference in the eruption time of the successors of between the root canal filled deciduous teeth and unfilled control teeth.

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The purpose of this paper was to investigate the actual state of the environmental and oral health conditions of the outpatients who visited the pedodontics Clinic of Higashi-Nippon-Gakuen University, Dental Hospital for during a 5year period (from April 1979 to March,1984).
The following results were obtained:
1) The subjects were 1115 children (563 boys and 552 girls) who were visited the clinic. A large number of patients visited in January, June and August.
2) About 80.1 % of all the outpatients had caries as their chief complaint. However in recent years, outpatients coming to the clinic for oral health examinations and caries prophylactic treatment as their chief reasons are increasing gradually.
3) About 54.7% of the patients had some sort of systemic disease or idiosyncrasy at the first examination. About 5.3% of patients had some type of handicap at the first examination.
4) About 33.4% of all the outpatients had bad oral habits such as finger sucking and bruxism.
5) About 93.9% of the patients brushed their teeth every day and about 49.3%of them brushed their teeth only once a day. About 8.4% of the patients brushed their teeth over three times a day.
6) As for frequency of eating snacks or meals, about 85.7% of patients had snacks or meals over one time a day. For the older children, the number of patients who had snacks or meals over twice a day was smaller.

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The purpose of this report was to survey the incidence and treatment of dental caries in the outpatients who visited the Pedodontic Clinic in Dental Hospital of the Higashi-Nippon-Gakuen University Dental Hospital from April,1979to March,1984. The subjects were 716 children,357 boys and 359 girls, who were treated and examined regularly in our clinic handicapped patients excepted.
The findings were as follow:
1) The average of age of the 716 outpatients was 5 years 1 month and 3 years the older children occupied the largest percentage.
2) As for the percentage of the df index, it was found that the df of all the deciduous teeth was higher than the Report on the Survey of Dental Diseases (1981) by Medical Affairs Bureau Ministry of Health and Welfare Japan.
3) With the lower and the upper posterior teeth (deciduous), the incidence of caries was showed an extremely high score from an early stage and the rate of the incidence df caries increased markedly. While with the lower anterior teeth (deciduous), caries incidence was comparatively low.
4) The trend of the incidence of caries with the first permanent molar was similar to that of the deciduous permolar teeth.
5) Most of the pulpotomy for the deciduous teeth used the formocresol-pulpotomy technique.

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