A lower deciduous inciser exhibiting dentinogenesis imperfecta (D. I) obtained from a 6-year-old boy with osteogenesis imperfecta (Shields' Type I) was examined by means of light microscopy (LM), scanning electron microscopy (SEM), and Xray microanalysis (XMA).
With LM, the dentin displayed a sparse and irregular tubular pattern near the dentinoenamel juncton (DEJ) and only few or no tubular structures in the area corresponding to the circumpulpal dentin. Between these two areas, cleft-like structures were characteristically noted. Structural irregularities in the dentinal tubules were also shown with SEM observation.
XMA demonstrated that the distribution of both Ca and P in the dentin of DI teeth was apparently lower than that in the normal deciduous incisor used as a control. Specifically, an area along EDJ at a distance of 25-35μm, corresponding to the mantle dentin, revealed extremely low or no distribution of the both elements.
From the present observation, it is suggested that the genetric disorder mainly involved in the primary odontoblasts and consequently results in the disturbance of calcification, especially that mediated by the matrix vesicles, and shortening of the cell life. After the death of these cells, the cells originat in, from the undifferentiated pulp cells may participate in the deposition of another irregular dentin.

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A system to measure the three-dimensional architecture of the occlusal surface was developed to clarify the three-dimensional change of the morphology of occlusal facets that was considered as the trace mark of the chewing function. The threedimensional measuring and analyzing system of the occlusal surface was composed of two components, the measuring system to obtain the three-dimensional coordinates on the surface contour of the tooth crown and the analyzing system to calculate the minute morphology in the three dimensions. The reproducibility of this system was evaluated with use of the standard block of stainless steel designed for this purpose and was shown to be very accurate.
By application of this system, the three-dimensional changes of the occlusal facets on primary canines and primary second molars were investigated on the serial primary dental casts taken before and after the eruption of the first permanent molars from eleven children (seven boys and four girls).
The results were as follows:
On the primary second molars of the maxilla and mandible, before the eruption of the first permanent molars, the occlusal facets were distributed mainly on the functional cusps. The occlusal facets were found also on the non-functional cusps after the eruption of first permanent molars. As a consequence, the increase in the number of occlusal facets from before to after the eruption of first permanent molars was statistically significant for both maxillary and mandibular primary second molars. In regard to the morphological change in three dimensions, the occlusal facets that were facing mesially or distally before the eruption of first permanent molars changed its direction buccally or lingually and became almost parallel to the datum plane of the mandibular dental arch after the eruption of the first permanent molars. It was also found that the occlusal facets of both jaws in the occlusal relationship were lamost parallel to each other. In addition, the amounts of angular change before and after the eruption of first permanent molars were significantly correlated between the maxillary and mandibular occlusal facets. It can be concluded that the coordinating change of the occlusal facets in three dimensions may exist between both jaws during the development of chewing function.

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A histopathological study was attempted to investigate the pulpal response to diammine silver fluoride which was applicated on the exposed pulps.
Cavity preparation was performed on healthy permanent teeth of mongreal dogs with an air water spray in order to expose the pulp tissue on the small area of the cavity floors. In the experimental group (28 teeth),0.01 ml 38% diammine silver fluoride solution was applied on the cavity floors and the exposed pulps for 3 minutes after cavity preparation. In the control group (27 teeth), nothing was applied on the cavity floors and the exposed pulps. All the cavities of these groups were left open to the oral environment without any restoration. The specimens were processed for histopathological evaluation at 3,7 and 30 days. The teeth were fixed in 10% neutral buffered formalin, embedded in celloidin, serially sectioned through the pulp and stained with hematoxylin and eosin.
The following observations were obtained.
1. After 3 days, both of the 2 groups showed such severe histopathological changes as necrosis, suppurative inflammation, round cell infiltration, bleeding and hyperemia of pulps with high percentages (77.8%-100%).
2. After 7 days, both of the 2 groups showed partial-necrosis, supprative inflammation, round cell infiltration, bleeding and hyperemia of pulps with high percentages (63.6% 100%).
3. After 30 days, the percentages of supparative inflammation and round cell infiltration decreased, though the percentages of complete-necrosis of pulps increased in both of the 2 groups.
4. After 30 days, cicartrization of pulps and apposition of dentin on the pulp chamber wall were observed in each of 2 teeth (25 %) in the experimental group, and in each of 2 teeth (16.7%) in the control group.
5. In the 2 groups, all of the teeth except one 30-day specimen in the experimental group and one 7-day specimen in the control group, which were histopathologically evaluated as fairly success, were histopathologically evaluated as failure.
6. Application of 38% diammine silver fluoride solution did not show any protective efficacy to exposed dental pulps.

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This study was conducted to investigate some biochemical characteristics of compound odontoma obtained from three cases, all found in the mandible. The results were compared with data obtained from deciduous teeth (3) and permanent teeth (3). The mole ratios of calcium to inorganic phosphorus (Ca/P) among three groups were deviated between 1.67 and 1.68 in the enamel extracts and between 1.65 and 1.69 in the dentine extracts. No significant differences were found in each case. Amino acid analysis of dentine showed apparent differences among these groups in the degrees of hydroxylation of proline (Hyp/Pro+Hyp) and of lysine (Hyl/Lys+Hyl). Hydroxylation rates of proline were 43.1±0.98% for the permanent teeth,44.4±0.47% for the deciduous teeth and 40.9±0.44% for the odontoma. Hydroxylation rates of lysine were 32.0±0.67% for the permanent teeth,27.3±0.0% for the deciduous teeth and 26.5±0.46% for the odontoma. T-test confirmed the significance of the differences between the permanent teeth and odontoma in the case of lysine (p<0.5%) and between the deciduous teeth and odontoma in the case of proline (p<0.5%).
These results suggest the differential organization of dentine matrix between human permanent teeth, deciduous teeth and compound odontoma.

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Calcification of the teeth, zise of the teeth and dental arches, facial growth and calcification of the carpal bones were studied in three children with clinically different severities of vitamin D-dependent rickets (DDR), type II, with alopecia, which is 1,25-dihydroxyvitamin D-receptor-defect rickets and is particularly resistant to treatment with calciferol analogues. They were treated in a pediatric clinic with large doses of 1α-hydroxyvitamin D₃ (1α-(OH)D₃) and 2g/day of calcium lactate.
The results were as follows:
1. Hypoplasia of enamel of the deciduous teeth was not found.
2. In the deciduous teeth, large pulp chambers and thin dentin were seen in radiographs before treatment. In patients 1 and 2, these abnormalities were reversed by treatment. In patient 3, who had the severest manifestations, large pulp chambers and thin dentin decreased but still remained.
3. Growth of permanent teeth was retarded before treatment and during resistance to treatment. After effective medication, it caught up and was corrected.
4. Problems concerning maxillary and mandibular growth were not found. However Nasions of three patients were more front and lower and Orbitales were lower than standard.
5. In patients 1 and 2, the calcification of carpal bones was accelerated and in patient 3 retarded.
6. Mesiodistal dimensions of erupted deciduous and permanent teeth were within the standard range, except for patient 3, who had smaller lower deciduous teeth.
7. A ground section of the extracted upper right first deciduous molar from patient 3 showed abundant interglobular dentin and lack of predentinal layer. From the above findings, it was felt that in all probability dentinogenesis was disturbed by the DDR type II. Abnormally large pulp chambers and thin dentin could be corrected by effective medication.
In patients with vitamin D-dependent rickets type II, oral hygiene for caries prevention is the most important procedure, because the pulp will be infected immediately after initiation of dental caries.
After effective medication, permanent teeth and jaw bones will probably grow normally.

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Trace elements (Cd, Zn, Pb and Cu) levels were determined in lower deciduous incisors which were collected from four areas (Sapporo, Yokosuka, Nagano and Kitakyushu) in Japan. Samples were divided into enamel and dentin, and dissolved with nitric and dried at 80°C. Each element was separated chomatagraphically using an aceton-HCL gradient solution with a cation exchange resin and then analyzed by atomic absorption spectrophotometry.
>The results were as follows:
>1. Ca, P, Ca/P ratio levels showed no significant differences among four areas.
>2. In the enamel,
>(1) Cd levels of each area were 0.593μg/g (Yokosuka)>0.315μg/g(Sapporo)>0.261μg/g (Nagano)>0.222μg/g (Kitakyushu).
>(2) Zn levels of each area were 174.912μg/g (Nagano)>157.473μg/g (Yokosuka)>150.971μg/g (Kitakyushu)>128.980μg/g (Sapporo).
>(3) Pb levels of each area were 8.412μg/g (Kitakyushu)>7.925μg/g (Yokosuka)>5.426μg/g(Sapporo)>4.285μg/g(Nagano).
>(4) Cu levels of each area were 9.276μg/g (Kitakyushu)>6.928μg/g (Nagano)>6.178μg/g (Yokosuka)>4.389μg/g (Sapporo).
>3. In the dentin,
>(1) Cd levels of each area were 0.214μg/g (Sapporo)>0.184μg/g (Kitakyushu)>0.145μg/g (Nagano)>0.119μg/g (Yokosuka).
>(2) Zn levels of each area were 124.152μg/g (Yokosuka)>112.242μg/g (Nagano)>111.952μg/g (Sapporo)>111.456μg/g (Kitakyushu).
>(3) Pb levels of each area were 3.584μg/g (Kitakyushu)>3.019μg/g(Yokosuka)>1.819μg/g (Sapporo)>1.523μg/g (Nagano).
>(4) Cu levels of each area were 3.734μg/g (Kitakyushu)>2.221μg/g (Nagano)>2.098μg/g (Yokosuka)>1.664μg/g (Sapporo). Therefore, the results suggest that the trace elements levels in deciduous teeth depended on the environmental condition of each area and the deciduous teeth could be a useful material as an environmental contamination indicator.

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The pulp chamber floor of 39 primary first and second molars of 10 mandibuiars of the Indian scull was investigated with a scanning electron microscope for the presence of accessary foramens. All of the teeth investigated were in II A stage of Hellman's dental age.
The teeth were sectioned with a diamond disk with a point of 1.5 mm apical to the external furcation area, and 5 mm coronal to the cervical line. The teeth were washed with a supersonic washer and dried. The specimens were mounted with the pulpal floor facing upward on an aluminium stub, plated with gold and observed with scanning electron microscope.
As a result of this investigation the following conclusions were obtained.
1) Accessary foramens were observed in 4 mandibulars out of 10 mandibulars and in 14 teeth (35.9%) out of 39 teeth.
2) The maximum 10 and minimum one accessary foramen were found with an averrage of 2.8 per tooth.
3) Accessary foramens were observed with high frequency in the central portion of the pulp chamber floor.
4) The diameter of the opening of the accessary foramens of the mandibular first molars were maximum 83μm, minimum 8μm and average 45.4μm. While maximum 51μm, minimum 15μm and average 37.3μm in mandibular second molars.
5) The opening shape of accessary foramens was classified into three types, round 56.4%, oval 28.2% and others 15.4%.
6) Accessary foramen tend to be present bilaterally in the same individual.
7) It seemed that there is an individual difference in the presence or absence of accessary foramen. One individual has many accessary foramens, while another individual lacks accessary foramen.

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The purpose of this study was to investigate the actual condition of the sport drink intake on children.
We conducted an investigation by means of questionnairs at 3 nursery schools and a day nursery in and around Hiroshima City, and using 505 answers with the comparison between 4 areas.
The following results were obtained:
1) Less than 10% of the children often took sport drinks and about 70% of the children sometimes.
2) In response to the question of when taken,40-50% of answers revealed that the drinks were taken when the children ill and 20-40% of answers were take from home.
3) In response to the question as to why children begin to take the drinks, many parents answered that they were advised by a doctor and a nurse to give their child sport drinks to prevent for dehydration, when their children were ill. This answer accounted for about 60% of the answers to this question.
4) Parents imagined that fruit drinks, carbonated beverages and beverages with lactic acid promoted tooth decay.
Also the image of cariogenecity was less than 100% fruit juices, home-made juices, sport drinks, cow milks and water or tea in that order.
The results suggest that parents regard sport drinks as beverages which do not promote tooth decay and give their child sport drinks frequency.

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Several kinds of substances such as acids and bacterial toxins diffuse from dental plaque into the salivary film which moves slowly between the plaque on the teeth and oral mucosa. The volume of saliva retained in the mouth before and after swallowing seem to be very important with respect to clearance of such substances from plaque.
In 30 subjects, five-year-old children of each gender, the volume of saliva in the mouth after swallowing (X) could be computed by measuring the potassium concentration in unstimulated saliva and in the expectrate after a five-second rinse with 3 ml of water immediately following a swallow. The volume of saliva normally swallowed was calculated from the unstimulated salivary flow rate and the normal swallowing frequency. The volume of saliva before swallowing (Y) was calculated as the total of (X) plus the volume normally swallowed.
The unstimulated salivary flow-rate was 0.22±0.14ml/min, the mean valucs of (X) and (Y) were 0.38±0.11ml and 0.50±0.15ml, respectively, and there were no significant differences in these values based on gender. These values were about half the values of those parameters in adults (Lagerlöf and Dawes,1985), and insertion in the computer program (Dawes,1983) of these values suggested that sugar clearance in the five-year-old children would be slightly faster than in adults.

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To study the influence of traumatic injuries to deciduous teeth on their permanent successors, we investigated 126 traumatized deciduous incisors of 66 children who had visited our clinic regularly after traumatic injuries, and whose permanent successors had erupted.
The results are summarized as follows.
1) Some developmental disturbances on permanent successors, such as concerning their eruption, or crowns, roots and pulp, were found in 72 teeth. Among these, influences on crown formation and calcification were most often found, and white discoloration in the enamel was recorded in 55 teeth, yellow discoloration in 4 teeth and hypoplasia in 11 teeth.
2) One successor erupted one and a half years after the eruption of its opposite, and two teeth erupted in torsiversion. Three successors had root angulation, while arrest of root formation was found in one tooth. Pulp canal obliteration appeared in two teeth before their eruption.
3) Developmental disturbances of the crowns tended to be more severe and had a higher ratio when traumatic injuries occured at a younger age. The range of the ages of the children at the time of injury was limited in cases of hypoplasia and yellow discoloration.
4) According to the diagnoses at the first visit, the severity of periodontal injury and the dislocational directions of deciduous incisors might relate to the disturbances of crown formation and calcification of successors.
5) According to the type of treatment, enamel hypoplasia was observed more frequently in the observation group and the extraction group. Yellow and relatively large white discolorations were found more frequently in the reposition group than in the fixation group.
6) In the endodontic therapy group, only relatively small white discolorations were found, but white discoloration was observed more frequently in the extraction after endodontic therapy group than in the extraction without endondontic therapy group after first visit.
7) White discoloration in the enamel was most often located in the both upper and lower teeth at the incisal third position on the labial surface.

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The purpose of this study was to investigate the influence of the etching times on the adhesion of the resion on the primary ground enamel.
Fifty extracted and frozen bovine mandibuler primary incisors were used. The etchant used in this study was 40% phospholic acid gel and the etching times were 0,10,20,30 and 60 seconds. All of the specimens were washed with an air water spray for 30 seconds atfer etching. The bonding agent and composite resin used in this study were Photo Bond and Photo Clearfil A (Kuraray Co. ). Shear bond strength on the ground enamel were measured. After the shear bond strength test, all the test surfaces of the enamel and resin specimens were observed using the SEM.
The following conclusions were observed.
1) The etching time which showed the highest bond strength was 30 seconds (80.10±13.01MPa).
2) When the enamel was etched with all of the etching times, the bond strengths were significantly higher than that of the enamel without etching.
3) The bond strength with 10 seconds of etching time was significantly higher than that with 20 seconds of etching time, and the bond strength with 30seconds of etching time was significantly higher than that with 10 seconds of etching time, and the bond strength with 30 and 60 seconds of etching time was significantly higher than that with 20 seconds of etching time.
4) On the enamel specimens after the shear bond strength test, clear prism structures were observed in the group which showed a higher bond strength.
5) On the enamel specimens after the shear bond strength test, the frequency of the resin tags were fractured inside of the enamel prisms was lower in the group which showed a higher bond strengths.
6) Thirty seconds is a sufficient time for etching on the primary ground enamel using Photo Bond and Photo Clearfil A.

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The purpose of this study was to investigate the influences of habitual side chewing and the characteristics of food on the masticatory muscle function in children.
A total of thirty persons were subjected to the study; 10 with deciduous dentition (designated as G1),10 with mixed dentition (as G2),10 with permanent dentition (as G3), none of whom had any gnatho-facial dysfunction. EMGs were recorded from the temporal anterior muscles and masseter muscles on both sides, and the mandibular movement on the frontal plane was recorded during chewing of boiled fish cake paste, chewing-gum and chewing of dried cuttlefish on both the habitual side and the non-habitual side. EMG activities obtained and periods of closed phase, occlusal phase and open phase in the pathway of the mandibular movement were measured with a personal computer system. The relationship between the total muscle activities at clenching in the intercuspal position and the total muscle activities at chewing were also evaluated.
The results obtained in the present study were as follows:
1) Influence of habitual side chewing on the rhythm of the mandibular movement during chewing of chewing-gum was not found in all groups. Influence on EMG activities was not found in G1 and G2, but were presented in G3.
2) Influence of the character of food on rhythm of mandibular movement was not clear in G1, but as found in the other groups, while EMG activities were influenced by the character of food in all groups.
3) The MA Index (the ratio of total muscle activities while chewing to total muscle activities at clenching) showed a decrease with age. As far as the results of the present study is concerned, it could be suggested that the proficiency of the chewing ability is dependent on the dentitional growth. Furthermore, the MA Index was considered to be appropriate for evaluating the masticatory muscle function in children.

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The purpose of this study was to investigate the changes of the mandibular movement during chewing-gum chewing in subjects ranging from children with deciduous dentition to adults with permanent dentition, and also to analyze the influences of malocclusion on the mandibular movement in children.
The subjects were divided into three groups based on the developing stage of the dentition: ie., i) 7 children; mean age 4.6 yrs-with deciduous dentition, ii) 9children; mean age 9.0 yrs with mixed dentition and iii) 10 adults; mean age 22.9yrs with permanent dentition. In addition,17 subjects who have malocclusion were also examined, who were subdivided into the cross-bite group (mean age 7.9 yrs)and progenia group (mean age 7.3 yrs). The mandibular movements were recorded with Saphon Visi-Trainer CII during chewing-gum chewing and the traces of mandibular movement recorded on the sagittal plane were then analyzed.
The results obtained in the present study are summarized as follows;
1) The chewing pattern of children with deciduous dentition was characterized by narrow width and large posterior deviation of the opening and closing pathway. During growth, the width of the pathways increased and their posterior deviation decreased.
The narrow width of the opening and closing pathways form the majority of the type of chewing pattern in children with deciduous dentition. On the other hand, the types of reversed and crossed pathways form the majority in adults.
2) The chewing pattern in children with malocclusion was characterized by small posterior deviation in the pathway.
The type of recersed cycle was ranked first among the chewing patterns of progenia patients, while there were no significant differences of chewing types between cross-bite patients and children with normal occlusion.
As far as the results of the present study is concerned, the changes of the mandibular movement on the saggital plane following the dentitional growth were characterisitic indicated. In addition, malocclusion such as cross-bite and progenia observed in the children may influence the chewing pattern.

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It has been well known that there are extreme amounts of intercrystalline spaces and large amounts of enamel matrix in fluolosed human enamel. Our previous study discussed the fact that amelogenins in developing fetal enamel matrix protein may have a role in regulating or controling enamel crystal growth. These results positively suggest that amelogenins degradation may be associated with the etiology of fluorosed enamel.
The purpose of this study was to examine the relationship of the crystalinity of fluorosed enamel of rats and the molecular weight of enamel matrix protein. The crystalinity of fluorosed enamel of rats, caused by the ingestion of fluoride containing water was evaluated with the microbeam x-ray diffraction analysis and the molecular weight of enamel matrix protein was examined by SDS-polyacrylamidegel electrophoresis.
The results obtained in the study are summarized as follows.
1) The plasma fluoride level of rats increased linearly with the fluoride concentration in the drinking water.
2) The microradiographs of maturing incisor enamel of the group with 100 ppmF-and 200 ppmF- injected showed diffused radiolucent zone from the subsurface toward the dento-enamel junction. The disturbances in enamel mineralization were most appearent in the 200 ppmF- group.
3) The crystallinity of the radiolucent zone of the fluorosed enamel decreased in both the a and c-axis directions, and particulary decreased more in the a-axis compared with the control.
4) The pattern of the SDS-polyacrylamid gel electrophoresis of the enamel protein in the mature stage showed higher remaining molecular weight of amelogenins in rats in the 100 ppmF- and 200 ppmF- group. These results suggest that in hypomineralized enamel caused by long-term administration of fluoride containing water, the degradation of amelogenin protein was disturbed, and consequently the crystallinity of enamel apatite decreased.

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The purpose of this study was to evaluate the influence of the maximum velocity of the mouth closing phase on the occlusal sound.
Six subjects examined were divided into two groups (children and young adults). Occlusal sounds generated by the tooth tapping were obtained with in microelectronic condencer microphone placed on infra-orbital and external auditory canal. Three parameters were used for the measuring points such as 1) maximum velocity of the closing phase,2) maximum amplitude of the occlusal sound,3) duration of the occlusal sound.
The results obtained in the present study were as follows:
1) The waveform of occlusal sounds obtained from infra-oribtal showed more clearly than that obtained from the external auditory canal.
2) With increasing velocity, both the values of maximum amplitude and duration showed a tendency to increase in both groups.
3) The prolonging of the duration was apparent in the children. The results obtained in the study suggest that the analysis of the occlusal sounds generated by tooth tapping can apply to aid in the functional diagnosis of occlusion in children.

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In permanent and deciduous dentitions, the frequency of congenitally missing teeth, supernumery teeth, conical teeth, fused teeth, geminate teeth, abnormal tubercles (basal ridge of incisor or canine, central cusps of molars, Carabelli's cusp, protostylid, and paramolar tubercles), and enamel hypoplasia (white spots, pigmentiation, and enamel defects) were surveyed. Furthermore, mesio-distal and bucco-lingual dimensions of the crowns were measured and the relationship between developmental disturbances of dental hard tissue and tooth size was examined.
For the deciduous dentition, the frequency of children with congenitally missing teeth, conical teeth and fused teeth was 7.2%,1.1% and 5.3%, respectively. Enamel hypoplasia appears with the following frequency; white spots (16.0%), pigmentation (6.4%), and enamel defects (5.2%). Mesio-distal widths of the upper canine and lower lateral incisors of the children with congenitally missing teeth was significantly smaller than the standard values.
For the permanent dentition, congenitally missing teeth, conical teeth and fused teeth were detected in 5.7%,3.0%, and 0.5% of the children, respectively. The frequency of children with basal ridge, central cusps, Carabelli's cusp, protostylid, and paramolar tubercles was respectively,1.1%,2.6%,7.1%,0.3% and 1,3%. Children with central cusps or Carabelli's cusp tended to have larger crowns, while children with congenitally missing teeth or conical teeth tended to have smaller teeth. As for enamel hypoplasia, white spots were detected in 24.9% of the children, and pigmentation was in 8.1%, and enamel defects were in 9.2%.
These results indicate that abnormality of tooth number and tooth morphology correlate with the tooth size and this tendency is more striking in permanent dentition than in deciduous dentition.

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The research on the development and injury of the hard tissue of teeth was studied by the pedodontic departments of nine dental schools. We participated in this research and studied histopathologically hypoplasia of the enamel in particular. There were seven sellected teeth which had obvious hypoplasia of the enamel. We conducted observations with the naked eye, replica, general microscopy, polarized light microscopy, fluorescence microscopy, and microradiography. Moreover we studied to classify these cases into three types, that is to say, the injury factors of whole body, locality, and unknown origin.
The results obtained were as follows.
1) As for the injury factors for the whole body, the bottom of the enamel defects were located corresponding to the incremental line of Retzius in the case of enamel hypoplasia of the deciduous teeth. Also enamel hypoplasia was located near the dentinoemanel junction corresponding to the surface of hypoplasia.
2) As for the injury factors with respect to locality, the bottom of enamel defects were located corresponding to the incremental line of Retzius. The dentinoenamel junction was irregular and discontinuous, still more a part of that area, and the dentin protruded or was exposed.
3) As for the injury factors of unknown origin, hypoplasia was located from the surface of the enamel but it did not spread. Also the hypoplasia of the enamel did not correspond to the incremental line of Retzius.
4) Five cases had fluorescence lines in enamel or dentin.

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Chondrodysplasia Punctata is a disease belonging to the metaphysia syndrom. This disease is characterized by endochondral punctata calcification of epiphysis or apophysis, short legs and hands, arthrogryposis, saddle nose, ichthyosis, cataract and mental retardation.
This report concerns a case of Chondrodysplasia Punctata (Rhizomeric form)in a 4 year 1 month old girl. Observations were made from the dental point of view, and the findings were as follows;
1) The mesio-distal and bucco-lingual lengths of all primary teeth were smaller than the standard size.
2) Measuring the dental cast, the width of the dental arch was found to be larger, but the length of the arch was found to be smaller than the standard size.
3) The value of the palatal height was slightly smaller, compared with that of the normal children.
4) According to X-ray cephalometric analysis, the growth of the mandible was insufficient.
5) An enlargement of the angles of the teeth axes of the upper and lower central incisors was found.
6) The growth of the basal arches of the maxilla and mandible were shown to be retarded in the anterior portion.
7) Measurement of the area of the tubella sella triangle, revealed the posterior parts to be large and almost standard in the mesofacial part, and small in the mandibulo-facial parts.

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For the investigation of the clinical dental manifestations of inborn errors of metabolism, the oral examination of twenty one children aged from 5 months to 15 years 5 months was performed at the pediatric clinic of inborn errors of metabolism.
The results were as follows:
1. In six of seven histidinemia patients, white spots, pit or hypoplasia of enamel, fused teeth, peg teeth or abnormal tubercles were observed.
2. In a patient with GM₁-gangliosidosis, the upper and lower central incisors had severe white spots.
3. In one patient with osteopetrosis, one of two glycogenosis type IX and one of two homocystinuria patients, white spots or hypoplasia of enamel were observed.
4. One patient with hypophosphatemic vitamin D-resistant ricket, one with vitamin D-dependent ricket type II and one with galactosemia patient had no enamel hypoplasia. It was strongly suggested that there is a specific relationship of histidinemia and GM₁-gangliosidosis to dental manifestations.

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The purpose of this paper was to investigate the dental situation of children who visited the pedodontics clinic of Nihon University at Dental-Hospital during the period from Jan.1983 to Dec.1987. The subject is the awareness in parents of 68 children who carried out the admisistraction of medical care. The results were as follows.
1) Recently we observed that the ratio of physically handicapped children was was on the increase among the first visit patients.
2) The priorcipal deseases of the physically handicapped children were cyclothymic, allergy and blood dyscreasia.
3) The majority of the patients visited for receiving caries treatment.
4) We presumed that the parents of the physically handicapped children showed deep concern for oral diseases.

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We made a follow-up survey on the TMJ dysfunction syndorome patients who visited our clinic, using questionnaries for the purpose of raising the dental management of TMJ dysfunction syndrome patients and obtained as following results.
1. The percentage of questionnaries which were sent back was 61.5% with the finished group, and was 38.9% with the discontinued group. The average percentage for all subjects was 50.7%.
2. From the results from all subjects who answered the questionnarie and sent them back, it was found that the ratio of the patients who had understanding of the explanation before the treatment of the TMJ dysfunction syndrome was 60.5%. The ratio of the patients who answered "I could not use the splint completely"was 2.6%, and the ratio of the patients who answered “I used the splint completely in spite of malaise when using it” was 84.2%. The ratio of the patients who answered “I felt that treat time was long” was 57.9%. The ratio of the patients who had a relapse of the symptom after treatment was 33.3%, but 22.2% of their symptoms were temporary and soon disappeared.
3. There were 4 questions which showed statistical significans differences between the finished group and the discontinued group. They were the attitude to the treatment after examination at first visit, period of time the splint was used, complaint of discomfort while using the splint, concerned mind of visiting interval.
4. The rate of the patients who complained of the limitation of jaw at the first time was higher with the finished group than with the discontinued group.

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It seems that active orthodontic therapy using multibracket appliances presents effective assurance of a physiological stable occlusion for TMJ dysfunction syndrome in adolescents.
The efficiancy and problems concerning the progress of active orthodontic therapy after splint therapy were examinated from the data of the change of occlusal conditions, and the function of masticatory muscles before and after therapy for TMJ dysfunction from four cases for which we performed orthodontic therapy activily.
1. All of the occuring symptoms of the TMJ dysfunction syndrome (limitation, pain, sound) in the progress of orthodontic therapy were concerned with using intermaxillary elastic. The symptom which occured in process of using only intromaxillary elastic was just a malaise of the TMJ.
Also the sound of the TMJ relapsed in the process of using class III intermaxillary elastic and recurred after the multibracket appliance was removed.
In this case, the condylar vertical position after orthodontic therapy changed from the lower position to the center position compared with the first visit.
2. Malocclusion was improved with orthodontic therapy in all four patients.
3. The function of the masticatory muscles after orthodontic therapy was improved in comparision with the first visit by evaluation of the masticatory muscles activity and the state of silent period.

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