The author established a new jaw movement analytic device small in size and light weight, which does not overly burden young children and is able to record natural jaw movement in terms of a minute jaw movement. The author also tried to develop the device to express a minute abnormality in jaw movement using the axis expressed as the center of the rotation in the jaw movement. The actual measurement wave shape was searched for by using a difference movement transformer to see the movement of the incisor model and by using a high precision form measurement change meter to see the movement of the left condylar model, and to see the precision of the prototype jaw movement analytic device. It was compared with a Nasohexsagraph® based on that wave shape.
The results were obtained as follow.
1) The wave shape of the prototype jaw movement analytic device corresponded to the actual measurement wave shape.
2) The wave shape of the irregular movement unusual part by the resin and screw could not be confirmed with Nasohexsagraph® but could be confirmed with the prototype jaw movement analytic device by applying the theory of the position of the shaft and its direction.
It was unacceptable with the convertional jaw movement analytic device to express a jaw movement in the voluntary point with respect to the condylar, and the molar. Also, before measuring it, it was difficult for a condition to be specified and to apply it to a lower aged child. A prototype jaw movement analytic device which can be measured from the image such as CT and can detect a minute movement wrong point by express in a shaft was developed successfully.

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Our long-term objective is to improve the clinical diagnosis and management of incipient caries of deciduous teeth. To this end, here we aimed at evaluating the usefulness and advantage of a laser fluorescence device DIAGNOdent^TMin detection and diagnosis of pit-fissure caries. A series of diagnostic measurements in vitro, which comprised visual inspection, fluorescent assessment by DIAGNOdent^TMa nd finally histopathologic validation, were performed at the non-cavitated occlusal sites of 32 deciduous molars. The sites for caries diagnosis were divided into two groups: 68 sites of pitfissure enamel without fillings and 29 sites with sealants or other filling materials. DIAGNOdent^TM measurements confirmed that the moistening vs dryness of tooth surface affected the fluorescent intensities markedly: moistening enamel surface led to a reduction in the fluorescent intensity, whereas dry enamel surface yielded more reproducible data. Based on these findings, we accepted as the DIAGNOdent^TMsc ore the value of fluorescent intensity measured under dry condition. In order to facilitate comparison between the three diagnostic measurements, the outcome of either visual inspection or histopathologic validation was also expressed by numerical scorings. Comparison of these diagnostic scores verified that, in both tooth surfaces without and with fillings, there was no statistically significant correlation between the scores of visual inspection and DIAGNOdent^TMm easurement. Notably, DIAGNOdent^TM readings showed positive correlation (p<0.05) with the results of histologic scoring. Since the magnitude of DIAGNOdent^TMs cores was highly dependent on the state and properties of enamel (e. g., microscopic surface defects, color, and thickness), one should be cautious as to the reliability of fluorescent measurement in both detection of dentin caries hidden by the intact enamel and assessment of the extent of demineralized dentin lesion. Regardless of these limitations, it is certain that the introduction of fluorescent measurement, in combination with the qualityimprovement of visual inspection, is useful for detection/prognostic diagnosis/management of incipient caries in the pediatric dentistry.

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The genetic traits commonly seen in teeth were studied by the twin method. The materials consisted of dental models and panoramic radiograms taken from 85 Chinese female pairs of twins at the mixed dentition stage. We examined the incidence rates of congenitally missing teeth except third molars, peg-shaped upper lateral incisors, shovel-shaped upper central incisors and Carabelli's tubercles on upper first molars, and the difference in concordance rates between the monozygotic and the dizydotic twins.
The results were as follows:
1. Congenitally missing teeth were found in 24 teeth of 19 twins, peg-shaped upper lateral incisors in 7 teeth of 7 twins, shovel-shaped upper central incisors in 122 teeth of 61 twins, Carabelli's tubercles in 66 teeth of 33 twins.
2. A significant difference in the concordance rates between the monozygotic and the dizydotic twins was observed only in the shovel-shaped upper central incisors.
3. After combining both the peg-shaped upper lateral incisors and the congenitally missing teeth into a same trait, a significant difference in the inter-pair concordance rate was also observed.
4. It is assumed that some genetic factors played significant roles both in the congenitally missing teeth including the peg-shaped upper lateral incisors and the shovel-shaped upper central incisors, any genetic effect for the Carabelli's tubercles on upper first molars was not, however, proved statistically.

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Mouthguards are well known to reduce the incidence of oro-facial injury in contact sports and the use of this device is gradually spreading among athletes in Japan. There however are scarcely any reports about sport injuries in children, especially oro-facial injuries, and about posibility of preventing for such injuries by wearing a mouthguard.
This study investigated the circumstance of oro-facial injuries and the awareness and wearing comfort of a mouthguard while using it. The subjects participating in this study were the children belonging to a Karate-do sport club.
The following results were obtained.
The incidence of injuries experienced at the Karate-do was 71% and the site of the injuries were almost always in the head and oro-facial region. Forty percent of the children were not interested in preventing injury. Although the diffusion of mouthguards was 68%, almost all (97%) of the children recognized the device. Almost all of the children wore the mouthguard at competitions but only 19% of them wore it during practice. Sixty-one percent was not satisfied with the mouthguard and difficulty in speaking, increased saliva output, cleanliness and difficulty in breathing were disclosed as their complaine. Discomfort when wearing the mouthguard improved somewhat within 4 weeks. The wearing comfort for a custom-made type mouthguard was better than that of the mouth-formed type in three children out of four.

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We performed caries treatment of 10 deciduous anterior teeth with class V carious cavity using Carisolv^TMth at can remove dentine caries infected with bacteria related dental caries, the questionnaire investigation and their prognosis.
The removals of the infected dentine was confirmed by a culture test of the bacteria at each step before, during and after applying Carisolv^TM.
The results were obtained as follows.
1. Before Carisolv^TMw as applied, bacteria related dental caries was found in 10 teeth of all subjects with the average 6.1×10⁵ CFU at the surface and the average 1.5×10⁵ CFU at subsurface of the caries dentine, respectively.
2. When Carisolv^TM was applied, bacteria related dental caries were found in 7 out of 10 teeth with an average 6.4×10⁴ CFU at the surface and in 8 out of 10 teeth with an average 7.7×10³ CFU at the subsurface of the caries dentine, respectively.
3. After Carisolv^TM was applied, the bacteria related dental caries were found in 4 out of 10 teeth with the average 1.3×102 CFU at the surface showing decrease rate of 99.989% and of 5 out of 10 teeth with an average 1.4×10 CFU at subsurface of the caries dentine, showing a decreased rate of 99.989% and 99.995%, respectively.
4. We gave some questionnaire counseling caries treatment by Carisolv^TMto the patients, and all of the subjects liked this method better than conventional methods such as the air turbine and engine instruments including local anesthesia.
5. Clinical prognosis at an average of 329 days was a fine based on no spontaneous and evoked pain, no gingival swelling and no pathologic findings by inspection and radiograph in all 10 treated by Carisolv^TM. From above results, Carisolv^TMap plication to caries treatment at anterior primary teeth was available.

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This study was conducted to investigate the relationship of the Cariostat test (CAT 21 test) and the amount of Lactobacilli present in the saliva (Dentocult®-LBw) ith caries status in 228 preschool children.
The effect of the amount of lactobacilli and how it affects the CAT 21 scores was also investigated.
The following results were obtained;
1. The caries prevalence rate and the mean dt scores of the subjects was 64.5% and 2.7, respectively.
2. A highly significant correlation was seen between the CAT scores and the amount of Lactobacilli present, compared with the mean dt scores. (Spearman correlation p<0.001)
3. The mean dt scores increased as the CAT scores increased. When the CAT score was 2.5 or higher, the mean dt scores also increased remarkably. (ANOVA p<0.01)
4. The mean dt scores also increased as the Dentocult-LB scores increases. (ANOVA p<0.01)
5. A highly significant correlation was seen between the CAT score and the amount of Lactobacilli present. It was observed that a low colony count of lactobacilli corresponded to a low CAT score (CAT 1.5 or lower) while a high colony count corresponded to a CAT score of 2.5 or higher.
According to the results above, the study indicated that children who had a CAT score of 2.5 or higher, also showed a remarkably high Lactobacilli colony count.

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It is important to have a good grasp of the prevalence of dental caries in a dental caries activity test for children. The Mucount® we used in this study is a testing system for the activity of cariogenic bacterium in saliva. It serves to assess the activity on the basis of the degree of adherence of the cariogenic bacterium. For some reason or other, there are few reports in which the bacterial colonies were identified in a clinical setting. To assess the caries prevalence in children through the caries activity test, we scrutinized the accretion of cariogenic germs by means of the Mucount®The subjects were 62 children who came in for a regular check up at the outpatient clinics of the pedodontics/orthodontics department of our hospital. After isolating S. mutans from the Mucount®wecompared electrophoretic patterns of enzyme-treated DNA. Furthermore, we went over the amount of water-soluble and water-insoluble glucans synthesized by S. mutans classified according to the degree of caries prevalence as well as the amount of glucosyltransferase- I using monoclonal antibodies. A summary of our findings is as follows.
1. The amount of S. mutans collecting on the Mucount® accounted for about one-third of the whole of the isolated amount.
2. A positive correlation was observed between Mucount scores and numbers of df+DF teeth only in the deciduous dentition.
3. The electrophoretic patterns of enzyme-treated DNA of the S. mutans isolated from the oral cavity of the same subject were the same. Between subjects, there were differences of more than 6.56 kbp in electrophoretic pattern.
4. The amount of glucans synthesized by S. mutans and the amount of GTF- I derived from children with the number df+ DF teeth working out at O were significantly smaller than those from children with the caries index exceeding 8.
5. There was no indication that low level of GTF germs induced a high level of GTF germs with the sucrose.
From the above, with the Mucount®scores alone, it was difficult to make an assessment of the prevalence of caries in children. To protect children from caries more effectively, our study suggested, it would be necessary to look into the property of S. mutans inhabiting the oral cavity of each person on an individual basis.

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To gain an insight into the way children observe the movements of other people, we videotaped the movements of a child who started walking from a stationary state (human image) and the movements of a pattern of luminous dots likened to the figure of a child (luminous image), and showed them to a total of 30 children who participated in this study. After measuring the eye movements of the subjects using a Visicon Eye-camera, we asked them about the luminous image orally. The data thus obtained were analyzed. The following is a summary of our findings.
1. From the frequency and duration of fixation, and the distribution of points of fixation, it was found that whether the image the subjects were looking at were human or luminous did not make any marked difference in their eye movement.
2. From the distribution of fixation points, it was clear that the children kept looking at the walking child and the luminous object as well.
3. Asked what it looks like, all the child subjects who were seeing the luminous dotted pattern in a stationary state said they were not sure what it was. When it started moving,14 of the subjects answered that they did not know, while 16 children said it looked like a person walking.
From the above, it was found that the children followed the moving object with their eyes whether it was a walking child or a luminous image without any preconception. This could offer a helpful suggestion in working on strategies for properly dealing with child patients who have behavioral problems.

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The purpose of this study was to determine the effects of an expansion plate containing an expansion screw on the mandiblar dental arch of beagles. The expansion plate was set for fifty-six days, and the expansion screw was adjusted weekly. Changes in tooth position, the horizontal plane of dentition, and the histological features of the periodontal tissues were then examined.
The following results were obtained:
1. The length of the dental arch in the experimental group was reduced, compared to the control group, whereas the cupula cuspal and collum dentis widths in the experimental group were larger than in the control group.
2. The cupula cuspal width was larger than the collum dentis width in the control group.
3. In the experimental group, osteoid had formed on the buccal surface around the alveolar crest, whereas bone resorption had occurred on the lingual surface. Furthermore, the periodontal ligament fibers adjoing the lingual surface of the middle portion of the tooth root were slightly degenerated.
4. The buccal side of the cementum was slightly thicker than the lingual side in the experimental group.
5. The medium interstitium of the mandible in the experimental group was slightly more spread, compared with the control group in which the medium interstitium remained the same.

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The purpose of this study was to clarify the change, with age, of three dimensional morphology in the orifice portion of the root canal of maxillary deciduous second molars using Micro-CT. The materials were teeth extracted from twenty Indian child dry skulls which were classified into four groups based on tooth eruption, namely, the Deciduous Dentition Stage, The Early Mixed Dentition Stage 1, The Early Mixed Dentition Stage 2 and The Middle Mixed Dentition Stage, respectively. The status of teeth eruption of each stage was as follows. Deciduous Dentition stage: in the teeth from the deciduous central incisor to the second deciduous molar reached the occlusion line. Early Mixed Dentition Stage 1: in addition to the Deciduous Dentition Stage, the first molar reached the occlusion line. Early Mixed Dentition Stage 2: in addition to the Early Mixed Dentition Stage 1, the central incisor reached the occlusion line. Middle Mixed Dentition Stage: in addition to the Early Mixed Dentition Stage 2, the lateral incisor reached the occlusion line. The skulls were the collections of the Department of Anatomy, Tokyo Dental College.
Each tooth was examined by Micro-CT to obtain raw data of its internal structures. There dimensional computer image was reconstructed from the raw data. Using each reconstructed 3-D image, diameters of the root canal orifices and volume ratio of the pulp cavity in the region of interest were measured, in addition to optical observation of the morphology.
The results were as follows;
1) The mesiobuccal root canal was crushed mesiodistally with age. The structure'at the middle area in the buccolingual direction was specially prominent. After the Early Mixed Dentition Stage 1, complicated divergence of the root canal was observed. The structures of the distobuccal root canal and lingual root canal were remarkable at the diverging side of the distobuccal and lingual roots.
2) From the Deciduous Dentition Stage to the Early Mixed Dentition Stage 1, all of the orifices decreased remarkably in diameter (mesiobuccal orifice; from 1.42 mm to 0.95 mm, distobuccal orifice; from 1.25 mm to 0.88 mm, lingual orifice; 2.47 mm to 1.89 mm). Similar tendencies were them observed in the mesiobuccal orifice from the Early Mixed Dentition Stage 2 to the Middle Mixed Dentition Stage and in distobuccal and lingual root canals from the Early Mixed Dentition stage 1 to the Early Mixed Dentition stage 2.
3) The volume of the orifice portion of root canal decreased remarkably from the Deciduous Dentition Stage to the Early Mixed Dentition Stage 2 (from 15.94% to 8.96%). However, only a few changes were observed from the Early Mixed Dentition Stage 2 to the Middle Mixed Dentition Stage.

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In the management of ectopically erupting maxillary first permanent molars, achieving their normal eruption as well as preventing premature loss of the second primary molars which exhibit resorption of the roots is desired.
In order to meet this requirement to the extent possible, we have examined a new method for the early treatment of these cases of ectopic eruption, and then applied it in clinical trials.
The results were as follows:
1. A new treatment process and appliance for the ectopically erupting maxillary first permanent molar was developed. The mechanism of the appliance is such that it can separate the spring wire from the fixed appliance based on the Nance holding arch. Such separated spring wire can be activated with little damage to the second primary molars of which the roots were resorped.
2. This method was sufficiently effective in the treatment of cases which presented severe root resorption.
3. This method was also effective in the early treatment of unerupted maxillary first permanent molars which develop a strong tendency to erupt ectopically.
4. The periodic dental check-up in the erupting period of the first permanent molars in children was quite helpful not only in the caries management, but also in the early detection and early treatment of the ectopically erupting maxillary first permanent molars.

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Two cases of supernumerary teeth in the incisor divisions of the maxillae, one in monozygotic twin brothers, and the other in monozygotic twin sisters were reported.
1. In case 1 (twin brothers), the subjects each had two supernumerary teeth. The senior brother had one inverted tooth and one tooth without inversion and the junior brother had two teeth without inversion.
2. In case 2 (twin sisters), the subjects each had one tooth located symmetrically.
3. Of the four supernumerary teeth of the twin brothers, three were conical in form, one of them being of the supplemental type. Those of the twin sisters were both of the tuberculate form. They were similar in brothers and sisters.
4. As to the cause of supernumerary teeth, the genetic factor was considered.

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We experienced a case of chronic graft-versus-host disease (GVHD) with various oral symptoms after bone marrow transplantation as a treatment of acute lymphoblastic leukemia. A 2-year-old Japanese male was suffered from a chief complaint of dental caries and bleeding from the gingiva. On the variety of oral symptoms, rampant caries, severe gingivitis, xerostomia, lechenoid lesion, atrophy of tongue palillae, leukoderma lesion on the tongue, candidiasis and cheilitis were seen. On the physical symptoms, volar erythema keratodes, rubedo of the chest and upper limb, hepatic functional disorder and keratoconjunctivitis caused by decrement of lacrimation were seen.
Five primary teeth with severe dental caries were extracted, and restoration with stainless steel crowns and composite resin were performed for the primary carious teeth which could possibly be conserved. Furthermore, thorough plaque control including gargling was instructed. We also applied laboratory tests for detection of HSV 1 and Candida albicans from the saliva sample. As both of the microorganisms were detected, we were concerned about the activation or reactivation of herpetic gingivostomatitis or herpetic cheilitis and candidiasis. The patient was provided with three-month recall schedule for oral care.
Pedodontists have to endeavor to reduce of the GVH reactions appearing in multi organs as the skin, eye and liver based on the prevention of infection disease through the prevention of dental caries and oral soft tissue disease by plaque control, along with therapy by pediatricians.

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Osteopathia striata with cranial sclerosis-megalencephaly is a bone dysplasia characterized by hypertelorism, macrocephaly, frontal bossing, a broad nasal bridge, palate anomalies, hearing defects, and mental retardasion. The radiographic findings include cranial sclerosis, linear striations in the long bones and iliac wings, small poorly aerated sinuses, scoliosis, and increased bone density. The sensory defects are disabling, but the condition generally is not life threatening. An eight-year ten-month old Japanese girl was brought to the out-patient ward of the Pedodontics and Orthodontics clinic, Tokyo Dental College Suidoubashi Hospital with the chief complaint of Orthodontic treatment and oral treatment.
In conclusion it was found that the maxillary-mandibular bone failed to thrive. The stricture of the maxillary dentition and many delayed eruption teeth were seen.
The possible aetiology, possible inferences for the developing dentition, and the need for careful assessment prior to ankylosis of the temporomandibular joints and maxillary-mandibular bone, orthodontic therapy are highlighted.

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