Clinical investigation on the conditions of actual use and secondary reactions of local anesthetics for children was performed to elucidate the safe use of local anesthetics. Data were collected from 4,145 subjects: 3,890 from the pediatric clinics of university hospitals, and 255 from the private pediatric clinics.
The results were as follows:
1) The age of the subjects ranged up to over 20 years, and children under 12 years of age accounted for about 90%.
2) The ratio of subjects with systemic disease or allergy amounted to over 20%, and asthma was the most frequent disease.
3) The ratio of children new to local dental anesthetics was 16.2%.
4) Local anesthesia was applied not only to pulp and surgical treatment but also to restoratory treatment.
5) Lidocaine with epinephrine was most frequently used as the local anesthetic drug. The dose of the drugs used was mostly under 1.0ml.
6) There were complaints of discomfort from some patients (during surgery 2.6%, after surgery 2.6%). The majority concerned pain, numbness and bite injury, so cases suspected of secondary reactions of local anesthetic drug were very rare.

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To investigate the present status of university instruction regarding pediatric dentistry and dentistry for disabled children, and handicapped pediatric (or adult) patient treatment at university hospitals, a questionnaire survey of 29 universities was conducted.
The results were as follows:
1. Diversification of th e school year in which lectures on pediatric dentistry are given and the number of houers for the lectures was noted among universities. Lectures on pediatric dentistry were most frequently performed in the senior year.
2. In lectures on pediatric dentistry, and those on dentistry for disabled children were given in most universities. The contents of the lectures on dentistry for disabled children were "dental treatment for mentally and physically handicapped children" and "pediatric diseases and dental treatment.
3. A Department of Dentistry for the Handicapped was established in 9 universities. Dentistry for disabled persons was taught as a subject in 21 universities including the 9 universities.
4. A Department of Dentistry for the Handicapped was established in university hospitals at 22 universities. Full-time dentists or full-time dentists and dentists concurrently serving in other departments were in charge of the department.
5. Outpatient dental treatment for disabled children was performed in the Department of Pediatric Dentistry at all of the universities. Furthermore, dental treatment not only for pediatric but also adult patients was performed at most universities.

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Cleidocranial dysplasia is an autosomal dominant disorder characterized by skeletal anomalies such as patent fontanels, late erupting secondary dentition, short stature, and rudimentary clavicles.The locus for this disease was mapped to chromosome 6p21. Mutations in the RUNX2 gene has been shown to cause cleidocranial dysplasia. RUNX2 is a member of the runt family of transcription factors and its expression is found in developing osteoblasts and chondrocytes. An 8-year-old Japanese male with the clinical diagnosis of cleidocranial dysplasia was the subject of this study. His clinical description included delayed closure of sutures, late erupting secondary dentition, and hypoplastic clavicles.We did not discover any past history of cleidocranial dysplasia in his family.
We performed mutational analysis for RUNX2 to determine if there was a m utation in RUNX2 in this patient. A missense mutation was detected in the coding region of the RUNX2. Arginine 225 (R 225) which was located at the C-terminal end of the runt domain was mutated and a replacement by tryptophan (R225W) was identified in the patient. This mutation, which results in premature termination in the runt domain, may produce a cleidocranial dysplasia phenotype by abolishing transactivation of the mutant protein.
We studied the clinical evaluations of phenotypes of previous cases with R225W mutation in RUNX2. We could not, however, find any significant correlation of genotype and phenotype.

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The present study aimed at investigating the effects of systemic administration of 1hydroxyethylidene-1,1-bisphosphonic acid (HEBP,1.0 mg P/day/kg b. w. ) on the recruitment and activation of osteoclastic lineage cells at discrete alveolar bone sites, namely sockets after extraction of the upper first molar and periodontal spaces surrounding the second molar roots. Five week-old male SD rats were used. Systemic-infusion of the agent was performed using an Alzet osmotic pump, which was implanted subcutaneously on the dorsal area and polyethylene tubing was inserted into the external jugular vein. The animals were sacrificed at 7 and 14 days after molar extraction and pump implantation. Maxillary specimens were dissected and then used for μCT observation and histomorphometric analysis. Osteoclastic lineage cells were identified using enzyme histochemistry for detection of activities of tartrate-resistant acid phosphatase (TRAP). In the control animals without administration of HEBP, the number of TRAP-positive mono- and multinuclear cells increased markedly at day 7 in the tooth sockets. Histomorphometric analysis regarding alveolar bone resorption activity and population of TRAP-positive cells showed that systemic HEBP delivery did not noticeably affect the recruitment of TRAP-positive cells in the tooth sockets and periodontium but caused inhibitory effects on osteoclastic maturation, i. e., multinucleation and development of ruffled processes and resorption lacunae. The appearance of apoptotic bodies under the HEBP regimen was distinguishable for mononuclear cells but not for multinucleated osteoclasts. Most remarkably, the above-mentioned multifaceted effects of HEBP on osteoclast lineage were site-specific, that is, prominent within the extraction sockets but only marginal in the root-surrounding periodontal space. This local variation in HEBP-dependent osteoclastic cell behavior may be explained by the accumulation and secondary release of HEBP in and from osteoid deposited during its systemic delivery period.

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The purpose of this study was to investigate the developmental transition from deciduous dentition to permanent dentition in low birth weight infants. Cases provided with study models of deciduous and permanent dentition were carefully selected.4 cases of very-low birth weight infants (<1500 g)and 4 cases of extremely-low birth weight infants (<1000 g) were obtained. Mesiodistal and labio/buccolingual widths of the tooth crown, and dental arch length and widths of both deciduous and permanent dentitions were measured from these study models. Measurements of the low birth weight infants were analyzed and compared to those of normal birth weight infants.
Our findings were as follows:
1. Both the mesiodistal and labio/ buccolingual widths of the tooth crowns of the deciduous and permanent tooth crowns of low birth weight infants were narrower than those of normal birth weight infants. This tendancy was evident in the labio/ buccolingual crown width.
2. The arch length in low birth weight infants was longer than, that of normal birth weight infants in the deciduous and permanent dentition. The arch width of low birth weight infants was narrower than that of normal birth weight infants.

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Eight hundred and eleven babies eighteen month of age were subjected to a dental survey from 2000 to 2003 to examine the relationship between susceptibility to dental caries and the method of milk suckling. They were categorized into the three groups, the suckling termination group, the breast feeding group and the bottle feeding group. The number of teeth affected by dental caries per baby was surveyed and the mean number of affected teeth per baby and the rate of babies affected by dental caries were then calculated for each group. Furthermore, a baby, with more than three anterior teeth affected by dental caries was defined as a milk feeders with caries and then the rate of milk feeders with caries was calculated for each group. Based on the analyses, the following interesting findings were obtained taiking into consideration their status of their ordinaly oral health as well.
1) The rate of babies affected by dental caries, the mean number of affected teeth for each and the rate of milk feeeders with caries for the breast feeding group were significantly higher than those for the other two groups, respectively.
2) The ordinal oral health condition for the breast feeding group was significantly lower than that for the other two.
3) The rate of babies affected by dental caries, the mean number of affected teeth for each baby and the rate of milk feeders with caries holder for the group with better helth were significantly lower than those for poor the group with poor helth.
4) The rate of milk feeders with caries for feeding with milk group and one was lower before fifteen months of age, but rapidly increased afterward. These findings suggest that a longer duration of breast feeding induced a higher rate of babies affected by dental caries, but that keeping better oral health for the breast feeding group could inhibit it. Dental health examination for babies at the early stage of twelve months of age will be thus recommended.

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The aim of this study was to assess the effects of the respiration and circulation of child patients during restraint dental treatment. The subjects were divided into the non-restraint group (19 child patients) and the restraint group (16 child patients).
The pulse rates (P. R. ) and percutaneous oxygen saturation (SpO₂) were measured with a pulse oximeter during dental treatment, and the maximum, and minimum values as well as the difference between the maximum and minimum (Δ) were compared between the non-restraint and restraint groups.
Based on the results, it was found that the maximum P. R. and ΔP. R. of the restraint group were higher than those of the non-restraint group with a statistical significance (P<0.0005), the minimum SpO₂ of the restraint group was lower than that of the non-restraint group with a statistical significance of (P<0.05), the ΔSpO₂ of the restraint group was higher than that of the non-restraint group with a statistical significance of (P<0.02).
These results suggest that careful observation of the patient and the monitoring with a pulse oximeter during dental treatment under restraint are necessary, because respiration and circulation can fluctuate considerably.
For the high-risk cases dental treatment under general anesthesia that is preferred to dental treatment under restraint.

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The subjects of this study were primary school children who had agreed to mouthrinsing with fluoride once a week after school lunch. The mouthrinsing program started in 1987 and continues up to the present.The number of DMF teeth was investigated at 11 or 12 years of age.
The results showed that since 1990 the numbers of DMF teeth have been lower than that of the Japanese average of 12 years of age. In 1997, ten year after the start of the program of mouthrinsing with fluoride, the DMF of this study was 0.75, while that of the average Japanese was 3.34. Regular mouthrinsing with fluoride and oral health care instruction by the school dentist was more effective in preventing of dental caries than only regular mouthrinsing with fluoride.

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The incidence of cleft lip and cleft palate is influenced by environmental factors, although the mechanism still remains incompletely understood. The aim of this study was to investigate the maternal environmental effect on occurrence of cleft lip with palate (CLP) in mice. A/WySn and C3 H/He strains were used. The F, hybrids from a reciprocal cross between A/WySn and C3 H/He were raised, and the reciprocal F, and A/WySn were used to produce as [A×F₁(A×C3H)](A; A/WySn, C3H; C3H/He), [A×F₁(C3H×A)3, [F1(A×C3H)×A] and[F₁(C3H×A)×A]N₂ backcross fetuses. Pregnant mice were injected on days 11 through 14 of gestation with 2.5 mg/mouse/day of cortisone. A laparotomy was performed on the 18th gestational day at which time the implant, resorption and litter size were recorded. Each fetus that attained at least Day 18 of development was checked for the presence of CLP. The frequencies of fetal resorptions that ranged from 36.4% to 45.0% did not differ significantly among the 6 groups. The rate of dams that had CLP fetuses was significantly higher in the A/WySn strain itself (35.5%) than in the A×F₁(15.5%)and in the F₁×A (22.2%). The mean number of implantations and the mean number of resorptions was higher in the dams that had CLP fetuses than the dams that had normal lip and palate fetuses, although the mean number of litter size did not show a significant difference. The highest incidence of CLP in the progeny was observed in the dams that had litter sizes of 8 not only A/WySn strain itself but also N2strains of mice. These results suggested that a high frequency of fetal resorption was affected by cortisone treatment, and the incidence of CLP might be influenced by litter size.

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Role-playing practice has been used in medical courses to teach appropriate attitudes to patients and to develop examination skills used in medical interviews. The purpose of this paper was to consider the effect of role-playing in small groups in teaching appropriate attitudes to the guardians of pediatric patients by undergraduate students in dental school.
The subjects were 113 fourth-year (pre-clinical training grade) undergraduate students at the Kanagawa Dental College School of Dentistry. The students were divided into 19 groups, with 5-6 students in each group. Then the role-playing in involving tooth brushing instruction (TBI) to the guardians of patients was performed by a 3-student subgroup. Each student played the roles of dentist, guardian and observer in turn, and the students who played the latter two roles and the instructor in each group evaluated the attitude and TBI skills of the student playing role of the dentist in the subgroup using OSCE. After all of the students played the three roles in turn, they made self-assessment of their own attitudes to the guardian and their TBI skills.
The average score of the achievement rate with respect to the SBOs for this practice (OSCE score)from the three different categories of evaluator, i. e. the instructors of each group, the other students as observers, the students, and those who played the role of the dentist (themselves), was evaluated. The average OSCE score from the instructors, the other students, and themselves was 89.0%,90.4%, and 82.8%, respectively. No significant correlation was observed between the OSCE score and the result of their paper examination (rs =the range of 0.1 to 0.2, p>0.1). According to the result of the questionnaire after the role-playing,98% of the students preferred the role-playing practice to the usual practice for teaching clinical skills. Most of them stated that they would like to have other opportunities for role-playing practice using various kinds of clinical situations.
Role-playing is one of the most effective methods for un dergraduate students to teach appropriate attitudes to patients or their guardians and the skills needed for the medical interview prior to clinical training. Moreover, small group learning is also effective in increasing the enthusiasm of the students for clinical subjects in both medical and dental courses by using the role-playing technique.

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The purpose of the investigation was to pursue the most suitable dental treatment for the patients with general diseases and the desirable system for them of collaboration between the pediatric dental clinic and the medical clinics.
The subjects were th e 100 child patients who were referred to the pediatric dentistry clinic from the medical clinics in the Iwate Medical University Hospital.
The following results were obtained by this su rvey.
1. The number of the first visit patients with ge neral diseases decreased 20% during these four years.
2. Highest the ratio of patients with neoplastic diseases of all of the patients referred was 36.0%. The second highest was that of patients with cardiovascular disorders.
3. Among the medical clinics in the Iwate Medical University Hospital that referred patients to the pediatric dental clinic, the pediatric clinic accounted for 67.0% which was the highest and reached about 80.0% if the pediatricians in the Circulatory Organ Medical Center are included.
4. The age distribution was almost the same as that of total first visit patients.
5. The most common reason for visit of patients with general diseases was the check up (40.0%), followed by dental treatment for caries (29.0%).
6. The number of dental caries of these patients was larger than that of the average Japanese child surveyed by the Ministry of Health, Labor and Welfare and the severity also exceeded the average.
This survey suggested the necessity for a proper oral treatment of patients with general d iseases. As many of these patients are young compromised hosts, the dental profession must continue a appropriate oral treatment from early age with enough understanding of the general state through close communication with the doctor in charge.

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It is well known that dental treatment can induce stress in children. This stress can lead to dental anxiety or fear of future dental care., it is therefore, important to know whether children are under a high degree of stress or not during dental treatment. It was reported that saliva Chromogranin A (CgA) might be a sensitive and promising index for psychosomatic stress in adults. The aim of this study was to verify whether saliva CgA may also be used as an index of stress in children. The subjects were 42 children ranging from 5 to 9 years of age (mean 7.5 years of age). Saliva samples were collected before and after each dental treatment by using a cotton roll. The CgA levels were determined using EIA. In order to determine the level of dental anxiety of the children and their personality traits, we used the Dental Sub-scale of Children Fear Survey Schedule (CFSS-DS) and a questionnaire that included a personality test. The CgA value was measured to be 3.17+/-22.17 pmol/mg protein at pre-treatment and 1.97 +/-1.79 pmol/mg protein post-treatment. Although the value of CgA of 83.8% of the children decreased, there were no significant correlations between CgA values and CFSS-DS. However, children with a high score on the CFSS-DS tended to have a higher CgA value. These results suggest that CgA may be used to verify child stress during dental treatment.

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We conducted a survey on the usage of the pacifier for p arents of children based on a questionnaire -a total of 3385 infants 1 y 2m,1y6m,2y0m,3y0m who had a dental check-up in health office and center of K city, Tokyo metropolitan for the period from June,2002 to March,2003.
The results were as follows:
1. Usage of the pacifier; the most numerous response of each age group was “Not used”.
2. Start of use; for each age,80 % or more of those who had used the pacifier started not later than 8 months of age.
3. As for stop of use, the response of from 1y2m and 1y6 m was at 6 months of age,2y0m and 3y m was at 12 months of age.
4. Impetus for use; popular response was “Prevention of mouth-breathing”.
5. The reasons for no use; the top response of each age group was “I let him (or her) try it, but he (or she) did not use it”.
6. When the pacifier is used; the top response of each age group was “Sleep or sleepy state”.
7. As for continued use; “I want to get him (or her) to stop before long (in a tangible way)” was the more popular response at the higher ages.
8. The reasons for stopping; the most numerous response of each age group was “He (or she) got tired of the pacifier”.

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The purpose of this study was to examine the longitudinal change of occlusion in children. The materials were study models obtained annually from 27 patients (17 boys and 10 girls) aged 4 to 12, having no history of significant tooth decay or orthodontic treatment. The interdental spaces in the primary dentition, the anterior occlusal relationship, the terminal plane, the relationship of the permanent first molar, and the change of occlusion from the primary dentition to the permanent dentition, were discussed.
The results of this study were as follows:
1. The majority of interdental spaces in the primary dentition was observed to be the developmental and primate space for both sexes.
2. The percentage of normal occlusion at 5 years of age was 47.7% for boys and 50.0% for girls; at 12 years of age it was 23.5% for boys and 30.0% for girls. The type of abnormal occlusion that increased mostly between the ages of 4 and 12 was crowding of teeth.
3. The terminal plane was most frequently observed for both the horizontal and vertical types. The most common type of occlusion for front molars was the Class I relationship, followed by the Class II and Class III relationships, in that order. The majority has been observed to shift from the vertical type to the Class I relationship.
4. Of the cases where there was normal occlusion in the primary dentition period,62.5% had normal occlusion for the permanent dentition. Most of the cases of overbite in the primary dentition period progressed to malocclusion.
Thusly, the percentage of those with normal occlusion decreases with age, and in many cases, malocclusion does not heal spontaneously. We can therefore conclude that this suggests the need to provide occlusal guidance concerning dental health of patients in childhood.

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The purpose of the present study was to examine the effect of postnatal feeding methods on the development of oral function in children. The subjects were 1357 children ranging from 2 years to 5years of age, the average age being 3 years 7 months. The questionnaire was answered by their parents concerning prenatal conditions and development of sucking and chewing. Subjects were then classified into three groups based on feeding method until the first three months after birth, these being the breast-fed (Br), the bottle-fed (Bo) and the mixed-fed (Mix) groups.
The results obtained were as follows:
1. The ratio of feeding methods for each group was 29.4% in the Br group,59.8% in the Mix group and 10.8% in the Bo group.
2. As for the weaning process, such as the starting and terminating age of feeding with baby food and the termination of the breast and/or bottle feeding, there was no significant difference in any of these items among the groups.
3. As seven items of the 18 items concerning the way of eating at present, such as being good or poor at chewing foods, disliking foods which need to be bitten off with the front teeth, spewing out foods from the mouth, dropping food from the mouth, the number of meal times a day and eating food by oneself were found to be significant, the children in the Br group were tended to show a much better development.
4. Significant differences were found among three groups concerning other items such as finger sucking, use of a pacifier, retardation of verbal development and characteristics.
In conclusion, these results suggest that the development of the oral function in children could be affected more than a little by the postnatal feeding methods.

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The ectopic eruption of the maxillary canine is often observed in pediatric dentistry. However, hardly any cases of the transposition of the maxillary canine can be found. We treated a case of the transposition of the maxillary left canine that was dislocated to the mesial side of the maxillary left first molar. The patient was an 11-year-old girl, who came for examination concerning the ectopic eruption of the maxillary left canine after this was pointed out in a school physical examination. Upon investigation, there was no indication of trauma of the teeth or disease in the entire body. The occlusion relation of first molar was Angle I on both sides. Also, an overjet of 4.0 mm and an overbite of 5.0 mm were found. The midline of the upper and lower jaw agreed. The patient did have crowding with an arch length discrepancy of the maxilla of -7.0 mm and that of the lower jaw of -11.2 mm in the mixed dentition analysis. The maxillary left canine was moved to the original position by using a multibracket appliance after the first premolar was extracted. The treatment ended in 3years and 5 months, and abnormal findings such as the root resorption could not be observed.

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A 10-year boy who had undergone radiation therapy was treated for dental caries and reduced saliva rate and was under a regular recall program. The findings are as follows:
1. The patient undergone radiation therapy. After 128 days, the saliva rate decreased under condition of both rest and activity. After 770 days, both saliva rates recovered to some extentbut were under half the rate before starting radiation therapy.
2. Similarly, the buffering capacity of saliva decreased but recovered 770 days after starting radiation therapy.
3. At 652 days, white spots were found on all of his teeth. The patient was instructed to use fluoridated dual component dentifrice at home, when brushing, while application of fluoride and professional mechanical cleaning was performed at the clinic. To estimate the effect of this treatment, we used Light-induced fluorescence until all teeth were observed to have remineralized. The rate of the luminance after 47 days increased by 3.4-7.6% and after 119 days, it increased by 3.4-13.5% as compared to luminance before treatment.

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It is well known that congenital absence of teeth may most likely occur from the distal part in each group of premolars and molars. According to the terminal reduction theory proposed by Fujita, single absence of the first premolar would not develop in the cases of partial anodontia of premolars, although single absence of the second premolar and the absence of both first and second premolars may occur.
We recently experienced four cases of the congenital absence of premolars, in which the pattern of the location of the absent teeth conflicted with the terminal reduction theory of Fujita.
This paper reports these four cases. Diagnoses of the congenital absence of the teeth were made from the findings of the orthopantomogram, and the identification of the absent teeth was made according to the findings of the positional relationship of the deciduous predecessor and the permanent successor.
[Case 1] There were second premolars on both sides of the mandible, despite the absence of the adjacent first premolars.
[Case 2] There were second premolars on the left side of the mandible, despite the absence of the adjacent first premolar.
[Case 3] There were second premolars on the left side of the mandible, despite the absence of the adjacent first premolar.
[Case 4] There were second premolars on both sides of the maxilla, despite the absence of the adjacent first premolars.
These observations suggested that the terminal reduction theory could not always be adopted to every case of partial anodontia of premolars.

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There are numerous possible causes of gingival hyperplasia. In most cases, proper oral hygiene is sufficient to regain normal healthy gingiva. For the advanced cases, however, it is not possible to achieve healthy gingiva only through oral hygiene. In this paper, we report on a severe gingival hyperplasia treated with a periodontal surgery.
The 15 year-old male patient prese nted a generalized gingival overgrowth in both the maxillary and mandibular archs. He was not able to chew as the gingiva was covering the mandibelar molar area. At the age of 6 months, his disease was diagnosed as epilepsy and he started taking an anticonvulsant drug. He was diagnosed as having severe myoclonic epilepsy in infancy at 3 years of age.
After extensive oral health care instruction, the excess gingival tissue was removed by the flap procedure under general anesthesia. The postoperative prognosis was favorable. It is desirable to remove the gingival hyperplasia, when it is severe as in this case, in order to improve the QOL of the patients.

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