The Japanese Society of Pediatric Dentistry has made various efforts to establish how to maintain oral health care for children. This article is concerned with an investigation into the actual condition of traumatic injuries of teeth in Japanese children, to set up possible criteria for prevention and treament of injured teeth.
The materials consisted of the clinical records of 2,008 traumatically injured teeth of 1,175 children, accumulated during one year from the first of April in 1993 to the end of March in 1994, supplied from 28 Departments of Pediatric Dentistry of dental colleges and universities in Japan.
Accidents to primary teeth were distributed from ages 0 to 10 years and were most common from 1 to 3 years of age. Traumatic injuries to permanent teeth were observed from ages 4 to 17years and were most likely from 7 to 9 years of age. The incidence of injuries in boys was higher than in girls and the value in boys was extremely high for permanent teeth, being twice as high as in girls.
The most common cause of trauma was a fall for both primary and permanent teeth, followed by a collision and falling. Though the primary teeth were more often injured by falling than a collision at ages 1 to 2 years, they were more likely traumatized after 3 years of age by a collision than falling. Traumatic injuries caused by collisions and blows were more often observed in the permanent teeth than in the primary teeth.
The anterior teeth in maxilla were most frequently affected by trauma in both the primary and permanent teeth, and the upper central incisors were the ones most prominently injured.
The most common types of trauma were loosening and concussion for the primary teeth, followed by luxation types which included the intrusion, extrusion and displacement and complete avulsion types. These accidents accounted for almost 65% of the total injuries. Crown and root fracturs occurred in over 20% of the injured primary teeth. For the permanent teeth, crown fractures occurred most frequently and the total amount of fractures including root fractures accounted for almost 50%. Although luxations of the permanent teeth occurred more often than fractures up to 7 years of age, the most likely type of injuries came to be fractures from 8 years of age.
Concerning treatments at the first visit, primary teeth with only loosening and concussion were not usually treated, merely 10% of those teeth being treated by repositioning and splinting or extraction. Replantation was also done in a few cases. Permanent teeth were often treated by crown restorations for crown fractures and by endodontical procedures for pulpal exposure. Replantation of permanent avulsed teeth was more frequently attempted than of primary ones.
Though we could elucidate the above actual condition of traumatic injuries of teeth in Japanese children, we should make a follow-up survey to ensure the prognosis of injured teeth and establish the most desirable criteria for traumatized teeth in children.

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It is very important to analyze the roentgenocephalometric films in a diagnosis of malocclusion. It has been noticed that the hight and weight of Japanese children have increased remarkably in the last 40 years, but we still use the standard values which were taken in the 1950's.
The data in our study were reconsidered with 100 lateral roentgenocephalometric films taken from Japanese children at the pedodontic clinic of Fukuoka Dental College and the new data were compared with the standard values taken in the 1950 s. Also, Kim's analysis was done both in the normal and malocclusion cases of the deciduous dentition.
The Results obtained from this study indicated that the new standard values of the lateral roentgenocephalometric analysis of the normal deciduous dentition were significantly different from the past standard values on Occlusal plane, L-1 to Mandibular and FH to SN etc.
The Kim's analysis clearly indicated the characteristics of a malocclusion in deciduous dentition.

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The relationships between different etching times using phosphoric acid and the bonding ability of pit and fissure sealant with permanent enamel were investigated for the morphological changes of conditioned enamel surfaces.
Morphological changes on enamel surfaces using phosphoric acid etching were observed with use of a scanning electron microscope, and compared among the etching times of 15,30 and 60 seconds. The observed surfaces with longer etching times showed more progressed etching patterns with the dissapearance of prismless enamel and exposure of enamel rods, and the occlusal smooth surface showed a more defined etching structure when compared to the area around the pits and fissures.
The bonding ability of sealant using different etching times was compared with the thermal cycling test and the dye penetration test. The results obtained by the observation of marginal leakage and gap formation at enamel-sealant interface revealed that the 15-and 30-second etching groups showed a significantly better marginal seal than the 60-second etching group. Also, the 15-second group showed fewer gap formations than the 60-second group. However, it was found that superior marginal seal did not always guarantee intact bonding at the deeper portion around pit and fissure.
Therefore, it is concluded that a morphologically well-etched enamel surface does not simply correspond to sealant bonding ability, indicating that there should be the optimal extent of enamel etching.

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Since 1985 we have undertaken the Project of the Community Dental Health for persons with handicaps in Kitakyushu City. In this paper we present the system of our project and analysed the result of the questionnairsa t the first examination.
The results were as follows.
1. The number of participants was 304 and the program ran for 3 years.
They were all commutingc hildren and had mentalr etardationa nd other complications.
2. As to the condition befor first commuting institutes, all of the children were divided into 3 groups. First was Group A, with those who had early habilitation and nursary, secondly Group B with those who had gone to the day nursary, and thidly Group C with those who not gone to any institute and stayed at home all day.
Almosto f the Group A childrenh ad had dental examinationt, reatment, or oral hygienicl ectures at the handicap center.
On the other hand in Group B and C, many children had been to general practitioners and a dental college. Above 50% of Group B and C had not had any dental care until our dental examination.
3. The children of Group A and Group B who had been examined at the dental college, all recieved dental treatment but 10% of the children of Group B had not had dental treatment for various reasons and until our examinationt heir dentalc aries had been left untreated.
4. The children had not undergone dental treatment befor commuting to the institutes were 89 and 8%of the children have been refused the dental treatment by the dentists.
5.96% of the mothers in Group A attended lectures about tooth brushing. However, only 50% of the mothers in Group B and C had attended lectures.
6.33% of the children had snacks after dinner, up to the time when they went to bed. Especilly in Group C many children usually had the cariogenic snacks.
7. As to drinking after dinner the situation was the same as with the snacks.

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This study was to search for and to establish a practical technique for protection of the proximal surfaces of primary molars as well as of young permanent molars which are intact or incipiently carious, by applying a fluoride releasing coating material, and to evaluate its efficacy as a clinical procedure by comparing this method with that of 2% NaF topical application.
Two hundred and five proximal surfaces of primary molars and 21 mesial surfaces of the first permanent molars of children visiting pediatric dental clinic of the Tsurumi University Dental Hospital, selected by visual and tactile examination with bitewing X-ray surveys, were the subject of this study.
After applying the fluoride releasing resin coating material, these surfaces were examined clinically for 2 years with regard to the protection of these surfaces against carious involvement.
A control group of 177 proximal surfaces of primary molars to which 2% NaF jell was topically applied, was also observed clinically for 2 years.
The protection rates of the proximal surfaces of first and second primary molars and first permanent molars were 71.8%,72.5%, and 100% respectively.
On the other hand, the protection rate of 2% NaF applied to the proximal surfaces of the first and second primary molars was 62.1%.
Based on these two year retrospective evaluations, the protection rate of the proximal surfaces to which the fluoride releasing resin coating material was applied, was significantly higher than that of topical application of 2% NaF jell (P< 0.05).
It can be said that application of the fluoride releasing resin coating material is a reasonably effective technique for the protection of the proximal surfaces of primary as well as young permanent teeth of children and a clinically acceptable procedure in pediatric dental practice.

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The purpose of this study was to investigate the influence of the age or sex factors in the change of the urinary catecholamine level in children during dental treatment. The subjects were 30 healthy children aged from 3 to 8, who received dental treatment with cooperative behavior during all of the procedures. They were divided into two groups: one group consisted of 15 preschool children (8males and 7 females), and the other group of 15 school children (8 males and 7 females). They received dental treatment, including infiltration anesthesia using 3% CitanestOctapressin (without epinephrine), rubber-dams, cavity preparation and restoration.
The urine samples analyzed were collected before and after the dental treatment. Dopamine, noradrenaline and adrenaline were isolated from the urine and quantitative analyses were performed. The ratios of the post-treatment catecholamine levels for the pre-treatment catecholamune levels were calculated as the conversion ratio.
The results were summarized as follows; In both age groups, there were no significant differences between the average calendar ages of the male and female children. The dopamine, noradrenaline and adrenaline concentrations taken post-treatment were higher than those thaken pre-treatment in both age groups. These changes showed that dental treatment accelerated the synthesis of dopamine, noradrenaline and adrenaline in both age groups. The conversion ratios of the noradrenaline and adrenaline of the preschool children were significantly higher than those of the school children. In the preschool children, the conversion ratios of the all indications of the male children were significantly higher than those of the female children. In the school children, the conversion ratio of the adrenaline of male children was significantly higher than that of the female children.
These results showed that there were important relationships between children's emotional changes during the dental treatment and both factors of age and sex. In the cooperative children, the emotional changes during the dental treatment of the preschool children were significantly higher than that of the school children, and that of the male children were significantly higher than that of the female children.

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We used the finite element method to analyze stress and displacement during trauma of the maxillary primary central incisors, alveolar bone and the successive permanent tooth germs for different degrees of primary root resorption.
The following results were obtained;
1. The force of the labial surface of the maxillary primary crown was displaced palatally on the teeth and alveolar bone. The force of the palatal surface was displaced labially.
2. The force of the labial, palatal surface and the incisor edge displaced more teeth, alveolar bone and permanent tooth germs for cases of greater resorption.
3. The force of the labial, palatal surface and the incisor edge caused greater stress to alveolar bone, but the stress of teeth showing greater resorption did not change.

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We conducted a research on the actual conditions of the habits of diet and oral hygiene in 315 of children attending two kindergartens and two of day-nurseries, downtown and in a suburban area, respectively, in the city of Hiroshima. The correlation between the data was analyzed statistically and the results were as follows.
1) In general, children prefer sweetened foodstuffs and fruits to vegetables. Children in kindergarden like sweetened foodstuffs and children in day-nursery like vegetables. Additionally, girls prefer fish and fruits, and younger children prefer grains. Concerning snacks, eighty percent of the children have them regularly and there were many children having them irregularly in the group having dental caries. Differences were found among the types of foods and the subjects.
2) There were significantly fewer children in the caries group who performed toothbrushing after lunch or after snacks. Nearly half of the children were checked daily after brushing by guardians. Furthermore, a higher ratio of checking was found in the lower age and lower orders of birth. Checking was done in the living room or lavatory in many cases. There was little usage of dental floss and a plaque detecter in many children.

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Fluoride profiles of enamel surfaces in the labial and lingual were examined in detail. Extracted lower primary central incisors were obtained in 5-year-old and 6-year-old children. The results obtained were as follows.
1) Between the two sites of enamel surfaces, the labial and lingual, no statistical differences in fluoride concentrations could be seen in both the 5-year-old and 6-year-old children.
2) In 5-year-old children, there were no statistical differences between the enamel surfaces of males and females. However, in 6-year-old children, fluoride concentrations in the enamel of males were statistically higher than those of females in the lingual sites (at depth; 10.0-30.0 μm)
.3) Fluoride concentrations of 6-year-old children were statistically higher than those of 5-year-old children except for the 1.0μm depth of the lingual site in females.

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The purpose of this study was to measure and classify the hardness of different kinds of foods, using the New Tactile Sensor for Detecting Hardness. A total of 171 routinely eaten foods were selected as samples.
The following results were obtained;
1) The measured values of the hardness of foods were indicated from OHz to 3868 Hz and had a wide distribution. Pot-steamed hotchpotch indicated the minimun value and caramel indicated the maximum value.
2) When the hardness of foods were divided into eight ranks, the distribution of the hardness of the foods appeared that 90% of all foods were concentrated from rank 1 to rank 4 which were soft foods.
3) According to the distribution of the hardness of foods, a lot of potato, seed-bean, fruit, egg-dairy products and marine products were distributed between rank 1 and rank 2. These foods tend to be softer than cereals, meat and vegetables. Compared with the other food, confectionery had a wide distribution from rank 1 to rank 8.
4) According to the hardness ranking of foods, the following typical foods were enumerated;
rank 1: pudding, tofu
rank 2: meat ball, boiled radish
rank 3: udon, wiener
rank 4: hamburg, white bread
rank 5: rice cracker, dried cuttlefish
rank 6 chocolate, lollipop
rank 7: none
rank 8: caramel, candy
5) As the Nea Tactile Sensor for Detecting Hardness has a high sensitivity and a broad limits of measurement, it is possible to measure the hardness of a variety of foods and a large number of foods in a short time.

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The purpose of this study was to investigate the oral functional development of infants with very low weights at birth and infants with extremely low weights at birth, and I measured the biting pressure and masticatory efficiency using A. T. P. particles. Furthermore I analyzed the plaster models to investigated correlation of tooth size and dental arch form.
The subjects were 10 children of II A stage of Hellman's dental age and 6 children of III A stage of Hellman's dental age in generally good condition and caries free with a birth weight of less than 1500 g. They were treated by the Department of Pedodontics, School of Dentistory, Showa University.
The findings were as follows:
1) The mean of the biting pressure for boys was 12.13 kg and for girls was 11.83 kg in stage II A, for boys was 19.00 kg and for girls was 23.83 kg in stage III A. In both dental stages, the average biting pressures of children with low weights at birth were lower than those of normal children.
2) The coefficient of the correlation of the biting pressure and chronological age for boys was r=0.912, for girls was r=0.787, which were considered statistically significant.
3) The mean of the masticatory efficiency for boys was 0.059 Abs and for girls was 0.050 Abs in stage II A, for boys was 0.112 Abs and for girls was 0.099 Abs in stage A. In both dental stages, the average masticatory efficiency of children with low weight at birth was lower than those of normal children.
4) The coefficient of the correlation of the masticatory efficiency and chronological age for boys was r=0.823, for girls was r=0.898, which were considered statistically significant.
5) The coefficient of the correlation of the biting pressure and the masticatory efficiency for boys was r=0.818, for girls was r=0.932, which were considered statistically significant.
6) Analyzing the plaster models, the average mesio-distal crown diameters of deciduos teeth were smaller than the normal value by -1 SD for most deciduos teeth. In addition the dental arch form was U-shaped, because the arch length was large and the arch width was narrow at the posterior part.
7) The average mesio-distal crown diameters and the dental arch form showed no correlation to the biting pressure and the masticatory efficiency.

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The purpose of this study was to observe posterior tongue movement with ultrasound using the mid-tongue as the standard.
As for the method of observation, the combined use of ultrasound and X-ray TV or straingauge pressure transducer were employed.
The present study was designed to compare the reproducibility of the results obtained using ultrasound and other equipment for mid-tongue and posterior tongue observations, to establish whether differences exist in the duration of use of ultrasound and other equipment for mid-tongue and posterior tongue observations, and to determine the reliability of ultrasound analysis of tongue activity during swallowing. The results obtained are as follows.
1. Reproducibility was found to be the same when a comparison was made of the results obtained by observation of the duration of the tongue movement using ultrasound with X-ray at the midtongue and posterior tongue. However, reproducibility was not found to be the same between ultrasound and the strain-gauge pressure transducer when the posterior tongue contacts the palate.
2. There was a difference in duration of use between ultrasound and X-ray TV at the mid-tongue. However, this difference was not observed at the posterior tongue. There were differences in duration of use between ultrasound and the strain-gauge pressure transducer at the mid-tongue and posterior tongue.
3. There was a difference in duration of use by subject from the start of the tongue movement to tongue contact with the palate. There was a difference in duration of use by scan from the start of the tongue movement to the end of the tongue movement.

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The purpose of this study was to confirm a appropriateness of measurement method and reproducibility of evaluation items as the first step in a series of study that examined a efficacy of thermography on a clinical diagnosis for temporomandibular joint dysfunction.
The obtained results were as follows;
1) The appropriateness and the reproducibility of the measurement method using of this study were confirmed.
2) The difference between right skin surface temperature and left that on muscles masseter was excellent about the reproducibility on evaluating at rest.
3) 3 items which were the maximum temperature change quantity, a reaching time to the maximum temperature change quantity and the consistency of right and left on a reaching time to the maximum temperature change quantity were suggested as the appropriate way of evaluating the temperature change of the skin surface on the mastication movements lord.

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Kinetic cavity preparation is a kind of cavity preparation method using a highspeed stream of carried aluminium oxide particles propelled by air pressure.
A significant defect of Kinetic cavity preparation systems is damage to carvo-surface sound tooth enamel. The purpose of this study was to establish a protective method for the carvo-surface sound tooth enamel during air-powder abrasive system cavity preparation, using protective varnish.
A total of 21 extracted human primary teeth were used for this experiment. Protect Varnish (Kuraray Co.) was applied to the tooth surface in single, double and triple coats in each of 7 cases respectively. The Kinetic instrument KCP-2001 J (Denics Co.) was used for cavity preparation. Class V cavities were prepared on the border areas of varnish coated and intact tooth surfaces, with 27 μm aluminium oxide particle and 7 kg/cm2 air pressure at a 1 to 2 mm distance at a right angle to the tooth surface. After removal of the varnish with a supersonic washer, specimens were dried and gold plated with ion-spatter, following which the cavity margin enamel was observed through a SEM.
The following conclusions were obtained.
1. Tooth surface enamel where coated with varnish appeared intact. However, tooth surface enamel without varnish coating appeared rough.
2. Protective varnish was found to provide a protective effect for carvo-surface sound enamel. It seemed likely that kinetic energy was absorbed by the soft varnish coating, thereby protecting the enamel.
3. Double and tripre coats of Protective varnish are effective for protection of carvo-surface sound tooth enamel.
4. In the group without protective varnish, the carvo-surface margin exhibited a round shape. While in the group with protective varnish the carvo-surface margin remained in a right angle form. Protective vernish was found to promote a sharp edge at the carvo-surface margin, during kinetic cavity preparation.

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Abstract: A phenomenon of regressive tendency on the morphogenesis of the lower second molar roots in mice was investigated using the seven inbred mouse strains which had differences in the rate of incidence for the occurrence of the Gutter-Shaped Root(GSR). Also we identified a criterion in order to evaluate the GSR using seven inbred mouse strains. Consequently the following conclusions were obtained:
1) We could divide the subjects into three types, type I (two roots), type II (incomplete GSR) and type III (complete GSR) as a degree of the fusion of the root in seven inbred strains. In two strains, C 57 BR and C 57 L, which had a high frequency for the occurrence of GSR, it was showed that there was a high percent of the type III. On the other hand, two strains, A and C 57 BL, apperaed only type I.
2) In the seven inbred mice, there were observed no significant differences based on sex, on the lower second molar root length in both the lingual and the buccal aspect.
3)Statistical differences were observed between the root length of the C 57 BR, C 57 L, and AKR strains and those of the A, C 3 H, C 57 BL, and RF strains (P<0.05). The root length of the C 57 BR, C 57 L, and AKR strains were much longer than those of the A, C 3 H, C 57 BL, and RF strains. The root size of the former three strains did not show trends toward reduction.
4) Accordingly, as the coefficients of variation were considerably low in both the lingual and the buccal aspect on the root length, it is suggested that the root lengths in inbred mice are little influenced by environmental factors.

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A method for determining the mandibular rest position in twenty-eight children with normal occlusion in the II A stage of Hellman's dental age was devised with the amplitude-histogram.
With this method, suitable ways for guiding the rest position were investigated and the mean values of the free way spaces on each guiding method as well as in each age group were calculated and compared with each other.
To the children with anterior cross-bite in the primary dentition the method was also applied for evaluating its usefulness to the functional analysis on such malocclusions.
The results were as follows:
1. The method based on the principle of the amplitude-histogram was found to be useful for determining the mandibular rest position of the younger children in primary dentition stage.
2. Even for disobedient children the method could be applied and the voluntary mandibular rest position was noticed as the only usable way among the three for such children.
3. Among the mean values of the free way spaces at each age, those in the rest position after swallowing tended to be the smallest and those in the rest position after opening the mouth the largest.
However, a significant difference among their values was only noticed in five year old children.
4. The mean value and its variance of free way spaces tended to decrease with age.
5. The suitable methods for guiding the mandibular rest position were different according to age, the voluntary rest position for three year old children, the rest position after swallowing and the voluntary for four year old children, and the rest position after swallowing for five year old children respectively.
6. The values of free way spaces of children with the skeletal type anterior cross-bite in primary dentition were significantly smaller than those of children with normal occlusion. In contrast with the above, the children with the functional type anterior cross-bite or with the mixed type occlusion were suggested to have greater values than those of children with normal occlusion.

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In this division, we have reported in the past, on the development of equipment to measure the 6degree freedom of the low jaw movement.
We have now developed a new system which is lighter and is able to be applied better clinically to infants and which enables the measurement of the upper and lower jaw movement. The properties and reproducibility in measurements were investigated to obtain the following conclusions.
1. A new instrument to measure the upper and lower jaw movement using magnetism has been developed by improving the conventional instrument for measuring the 6 degree freedom of the lower jaw movement using magnetism.
2. The S. E. in measurement for the vertical move was 0.15 mm in average for the 1.5 cm vertical move, and 0.29 mm in average for the 2.5 cm vertical move.
3. The S. E. in measurement for the horizontal move was 0.14 mm in average for the 1.5 cm move, and 0.28 mm for the 2.5 cm move.
4. The maximum individual C. V. in the maximum aperture, which is said to be relatively reproducible in the living body, is 4.1 mm in average, so the reference surface decision method is considered to be relatively reproducible.
5. There is a reproducibility in measurement with this instrument and it is considered to be possible to compare the measured values with those of other people and compare the yearly changes in measured values.

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Summary-The present study was undertaken to investigate the amelogenin gene expression in the ameloblasts of rat incisors suffering from enamel hypoplasia which was experimentaly induced by successive injections of the bisphosphonate.
Male Wistar rats, weighing 150-160g, were subcutaneously injected with 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) once a day for a week. As a control experiment, physiological saline was injected in the animals in the same way as HEBP. Twenty four hours after the last injection, they were sacrificed under general anesthesia. Their maxillary incisors and surrounding tissues were resected out. They were used for histological examination and in situ hybridization of amelogenin mRNA. In the HEBP injected rats, several islets of enamel were formed along the dentin-enamel junction, and enamel-free zones were observed between these islets. In situ hybridization of amelogenin mRNA showed that amelogenin gene expression was uniformly observed in ameloblasts of the secretory stage in the control rats. In the HEBP injected rats, amelogenin gene expression was observed not only in the ameloblasts on the enamel islets but also in the ameloblasts in the enamel-free zones. The signals of amelogenin mRNA expression in the HEBP injected rats were as intense as those in the control rats. These results indicated that successive injections of HEBP in rats did not alter the amelogenin gene expression in the ameloblasts, although they caused enamel hypoplasia in the forming ends of incisors.

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We investigated the actual condition of outpatients at the Pediatric Dental Clinic of Showa University Dental Hospital.
In this survey, the subjects were 1,015 handicapped children who had first visited the Dental Hospital from April 1989 to March 1994. The results were as follows:
1) The proportion of handicapped children was 24.6% of all new patients who had visited during these 5 years.
2) As for the age of the subjects at first visit,1 year-old and 2 year-s-old children represented a large percentage (52.6%).
3) They were classified into 4 groups according to their disorder: there were 251 children with physically or mentally handicapped,106 children with systemic disease,596 children with cleft lip and palate and 62 children with severe allergy.
4) For the course of treatment were selected oral hygiene instruction and caries control treatment, because most children were in dental stage of IC.
5) As for dental treatment, resin restoration was the most common treatment.

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The purpose of the study was to distinguish the characteristic between the conventional artificial nipples for the feeding bottle evaluated by the simulation study.
A sucking robot was devised and four types of the conventional artificial nipples, i. e. Pigeon with round outform and round hole (PRR), Chuchu with round outform and cross-cut hole (CRC), Nuk with elliptic outform (NE), and Beanstalk with elliptic outform and semilunar valves inside the nipple (BEV), were employed for the study. The volumes suckled for each nipple due to the negative sucking pressure and/or the existence of the compressive motion to the nipple were compared.
The following results were obtained;
1. There were marked differences depending on the nipples in the volume suckled due to the negative sucking pressure, besides the characterisitic differences which were brought about due to the additional compressing motion to the nipple.
2. BEV showed the lowest volume among the nipples employed due to the negative sucking pressure only. While when the compression motion was added to the nipple together with the negative sucking pressure, it showed the highest suckled volume.
3. Fairly high suckle volumes were shown in the PRR-M size, NE-S & M size, and CRC, PRR-S size in that order, due to both the negative sucking pressure and/or the compression motion.
4. Spontaneous leakage from the nipple hole was shown in the PRR nipple when the feeding bottle was set upside down, but any leakage was found in the CRC nipple with a crosscut hole.

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In order to elucidate the mechanism by which tannin-fluoride preparation (HY agent) strengthens tooth structure, I have carried out a series of experiments on the influence of the HY agent and its components on teeth. This time I investigated its effect on type I collagen.
The materials used in the experiment were a saturated solution of the HY agent, zinc fluoride, and strontium fluoride, a tannic acid solution with essentially the same tannic acid concentration as the HY agent, and a sodium fluoride solution of essentially the same fluoride concentration as the HY agent. A buffered phosphate salt solution was used as a control. I exposed type I collagen to each of these solutions and investigated changes in weight, the inhibitory effect these components had on swelling caused by acetic acid and water, and anti-enzymatic properties.
Not only did the HY agent and tannic acid markedly inhibit swelling of the collagen resulting from acetic acid and water, but it also dramatically elevated the anti-enzymatic properties. Similar results were also observed to a much lesser extent for zinc fluoride.

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This report investigated 1,466 primary-tooth restorations in 374 children, who attended the Nagasaki University Dental Clinic of Pediatric Dentistry in 1994. Data resulting from the investigation were compared with those obtained in 1984.
Results and Conclusions
1. Of all the restorations performed in 1984,37.5% were composite resin fillings; 28.8% were stainlesssteel crowns; 16.6% were metal inlays; 11.3% were amalgam fillings. On the other hand, of all the restorations performed in 1994,60.3% were composite resin fillings; 21.0% were metal inlays; 14.1% were stainless-steel crowns.
2. In 1984, of primary molars with decayed proximal surfaces,75.4% were restored with metal inlays,14.3% were restored with composite resin fillings and 10.0% were restored with amalgam fillings. In 1994, of the decayed proximal surfaces of primary molars,51.0% were restored with metal inlays and 47.5% were restored with composite resin fillings.
3. Both in 1984 and in 1994, composite resin fillings were used preferentially for primary anterior teeth in which caries extended only into the enamel or only into the dentin, and for primary molars in which caries extended only into the enamel. In 1994, composite resin fillings were used preferentially for primary anterior teeth in which caries extended into the pulp and for primary molars in which caries extended only into the dentin, too.
4. Compared with the results in 1984, in 1994, the percentages of the composite resin fillings increased both for primary anterior teeth and for primary molars. In 1994, no amalgam filling was used and glass-ionomer cement fillings were used as a new method.

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Dental treatment was carried out on a 12-year-old boy who suffered from multiple drug allergies. In the past, he had experienced 4 episodes of anaphylactic shock.
The patient had 21 permanent teeth and 4 deciduous teeth, with 21 of them seriously decayed.
We treated the teeth as follows.
1. First, specialist of allergiology was consulted to witness. LST and CAT conducted with several drugs.
2. For the estimated allergic reaction, several restricted drugs were used.
3. During the allergic examination and dental procedures, the vital signs of the patient were monitored carefully. Enough equipment and drugs for possible complications were always on hand.
4. After the dental procedures were completed, the patient was monitored for 30 minutes on the dental chair. Furthermore, close watch was continued for the next 30 minutes in the hospital.
5. For infected root canal treatment of the molars for which several prescribed medicines were required the patient was admitted in to our hospital for 4 days.
After the 21st appointment, all permanent teeth had been restored satisfactorily without any serious complications.

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We experienced a case of a completely impacted left mandibular second primary molar in a 3year 10-month old boy. We applied marsupialization and traction treatment using a magnet. In this case, the following clinical results were obtained.
1) It was found that a lower second primary molar was not erupted and an upper second molar extruded from an initial oral examination. X-ray showed that left mandibular second primary molar was complete. The mesial and distal root apex of the tooth was curved, but was not adhered. It was shown that the tooth germ of the left mandibular premolar, which was a successor to the impacted tooth, was not located.
2) After the observation period of six months from the initial visit, marsupialization and traction treatment were applied.
3) Two months later, after traction treatment, the occlusal surface of the impacted tooth was exposed.
4) After this period, exposure of impacted tooth was checked and the occlused balance maintained. It is suspected that the tooth germ of the left mandibular premolar was located from X-ray examination.

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We have encountered a 7 year 11 month old girl with a loosing of the first maxillary molar, as well as loose and early eruption of the first and second premolars involving gingival granuloma, which were her chief complaints at our dental clinic.
As for the oral symtoms, there was a diffuse alveolar bone loss in the area was detected by radiogram and skin eczema at the head and omphalos. Langerhans cell histiocytosis was suspected, and eventually was confirmed eosinophilic granuloma by biopsy.
The patient was treated by curettage the granuloma tissue in maxillary sinus without extraction of the loose teeth with curettage the gingival granuloma tissue, and chemotherapy with Vincristine, predonin,6-MP was cured completely with new remodeling of the alveolar bone. The first maxillary molar and the second premolar were able to be kept in her mouth. We undertook treatment with orthodontic procedure to the space loss of the first premolar which exfoliated naturaly to maintain her normal oral function. After the orthodontic procedure the remoded alveolar bone has remained in a healthy condition.

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Chin cap therapy conducted for six months on seven children (14 joints) three to five years of age was examined for its effects on the functions and morphology of the TMJ region.
1. Clinical data:
The anterior occlusal relationship impruved better and there was only rare disturbance of the mouth opening and pain in the TMJ region. Defectiveincisal passes in the mouth opening and TMJ noise were somewhat frequent.
2. Roentgenogram data:
Bone changes occurred in the some condyles, particularly those with bone sclerosis beneath the cortical bone of the upper surface showed change in some cases. The position of the joint head was posterior to the joint cavity and the joint space of the hind part became narrow and closed in some cases.
A periodic follow up will be conducted to evaluate changes in the TMJ region following treatment for deciduous crossbite.

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A 17-year-old-girl with bone dysplasia accompanied by delayed eruption came to our clinic where it was diagnosed for the first time. The results were as follows:
1) Orthopantomography findings showed delayed eruption, remained deciduous teeth, hypoplasic condyloid process, shallow mandibular notch and hypoplasic hyoid bone.
2) Postero-anterior and lateral projection date indicated insufficient assimilation of the skull bone, and the base of the skull and skull cap to show extensive consolidation and thickening.
3) Chest x-rays showed consolidation and thickening of the clavicle.
4) Based on the results of cephalo metric analysis, maxillary bone and mandibular bone excess growth was comfirned.
Based on the present findings, this case was diagnosed as cranio metaphyseal dysplasia.

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The development of the root subsequent to the crown exposure and traction was clinically evaluated in three cases of inverted and unerupted maxillary central incisors for which the developmental stages of the root were regarded as R 3/4, R 1/2 and R 1/4, respectively at the initiation of the treatment according to the classification of Moorrees et al.
In the case the treatment procedure was started at R 3/4, the root of the impacted upper central incisor was found to have already bent labially from X-ray exmination before treatment. The development of the root continued in the abnormal direction, so that the solid swelling of the mucous membrane due to the projection of the root apex was recognized after the procedure had been completed.
In the case the treatment procedure was started at R 1/2, the development of the root continued during the treatment in the same manner as the contralateral tooth with slight bending at the middle portion of the root.
In the case the treatment procedure was started at R 1/4, the development of the root continued thereafter in the same manner as the contralatelal tooth without root bend.
These observations indicated that the vitality and activity of the pulp tissue and the root forming tissue was not inhibited during the treatment procedure of inverted and unerupted maxillary central incisors with imcomplete root formation. It was also suggested that the eary treatment at or before the initial stage of root bend in these teeth resulted in successful guidance of eruption avoiding the bent and dwarfed root formation.

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The Kabuki make-up syndrome, which presents cryptogenic multiple anomalies, was first reported on by Niikawa, Kuroki, et al. in 1981. The manifestations of this syndrome include a peculiar face characterized by lower eyelid ectopion that resembles a Kabuki actor, a short stature, abnormal dermatoglyphics, skeletal deformation, and mental retardation.
The dental findings of the Kabuki make-up syndrome were malformed teeth, microteeth, cleft lip and palate, high-arched palate, anadontia and enamel hypoplasia, etc.
We experienced a case of the Kabuki make-up syndrome in a 9-year,4 month old boy. Our findings:
1. A peculiar face, skeletal anomalies, abnormal dematoglyphic and mild mental retardation were observed.
2. The dental anomalies were malformed teeth, microteeth, enamel hypoplasia, anadontia, superiorlabial frenum anomaly and high-arched palate. Anterior open bite and posterior cross-bite were observed.
3. The size of the teeth was smaller than the average.
4. X-ray cephalometric analysis revealed poor development of the maxilla.
5. What is important in the oral management of this patient is the prevention of dental caries. It is important aggressively to control caries by proper brushing and topical application of fluoride, pit and fissure sealant, etc.

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The purpose of this report was to make clear the hemostatic effect of dental splints in patients with bleeding tendencies.
Twenty-five patients, who received hemostatic treatment with dental splints in the period from October 1988 to August 1995 at Chiba Children's Hospital, were examined.
The patients were divided into 3 groups. Group I consisted of 7 patients with oral mucosal bleeding from hemorrhagic diathesis (HD). Group II of 11 HD patients underwent tooth extraction. Group III of 7 patients underwent tooth extraction with anticoagulant medication.
The results were as follows: In Group I, an idiopathic thrombocytopenic purpura patient whose platelet number had decreased to 0.7×10⁴/μl, could be relieved from severe gingival bleeding by the splint. In other two patients, one with acute lymphocytic leukemia and the other with aplastic anemia, both showing 1-2×10⁴/μl of platelet number, the gingival bleeding was controlled by the splint without supplement of platelet.
In the case of Group II, for instance, tooth extraction of a thrombasthenia patient was carried out without abnormal hemorrhage and therefore no transfusion of platelet was made. Furthermore, there were several cases of aplastic anemia whose teeth could be extracted without platelet transfusion in spite of a low number of 1×10⁴/μl.
However, in the severe type of hemophilia A, factor VIII was needed for tooth extraction.
In cases of Group III, bleeding after tooth extraction under anticoagulant medication was controlled with the dental splint.
From these observations, it would appear that these kinds of dental splints are useful to control oral hemorrhage and bleeding after tooth extraction of HD patients. Also it is thought that the splint is able to prevent bleeding after tooth extraction in patients during anticoagulant treatment.

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A nine year old girl, whose chief complaint was delayed eruption of the lower right first molar, was refered to the Dental Hospital of Asahi University School of Dentistry. Radiographic examination and biopsy were conducted for diagnosis and treatment planning.
Oral examination showed no demonstrable abnormalities at the site of the lower right first molar except for delayed eruption. The radiographical examinations revealed that the roots of the lower right first molar had been completed, and the cusps of the tooth still impacted at the level of the distal root apex of the lower right primary molar, in addition, the root apexes of the molar was situated closed to cortical bone of the mandible border. Well-definded radiolucency was shown around the crown of the tooth where the odontogenic fibroma was diagnosed by histopathological examination. The case was diagnosed as an impacted lower first permanent molar caused by odontogenic fibroma.
The impacted molar was guided in its eruption by fenestration and traction procedures. After 6months of traction the tooth was guided to the occlusal plane. Eventually, the occlusal relation between the upper and lower first molar was properly maintained.

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We experienced a case of a fractured mandible in a new-born baby in August,1982. Due to the inverse position of the baby, he was delivered with the aid of an operator's index finger four weeks earlier than the expected date.
The gingiva was torn at the middle of mandible, and the bone was denuded and fractured. Two days after his birth, while under intravenousa nesthesiat, he dislocatedm andiblew as reduced by hand, and two circumferential wires were put into position around the body of the mandible. An acrylic splint was then inserted. Postoperativeo bservancec ontinuedf or 13 years.
Tube feeding was given two days after the operation, and bottle feeding begun on the 10 th day: the baby was well fed. The splint was removed at age 16 days. At 15 months, _??__??__e?r?u_p ted. A was yellow and a little small, and the shape of A was a little abnormal. At 8 years of age, _??__??__??_erupted.1 was a little small, and located a little more lingually than 1. At 13 years of age, _??__??__??_were crowded and a scar was observed on the labial gingiva at _??__??__??_.1w as small and 1 was located a half tooth width toward the right beyond the midline.7 had not erupted yet; and 7 was half erupted. A notch was found at the lower edge of the mandible at 2. On a CT image, no abnormal findings were found. The width of his opened mouth was 42 mm. No abnormalitiesw ere seen at either mandibularj oint.

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