The purpose of this study was to clarify the correlation between the amount of gingival crevicular fluid (GCF) and the clinical parameters in children.
Fifteen hundred eighty two samples from 161 subjects (4 y 8 m-15 y 5 m average 9 y 10 m, with normal gingiva or gingivitis) were examined. Clinical parameters such as the Pocket Depth (PD), Gingival Bleeding (GB), Gingivial Index (GI), Debris Index (DI) and Alveolar Bone Resorption (BR)were recorded. GCF samples from the upper and lower anterior labial gingival crevices were collected with Periopaper®. The amount of fluid collected was measured using a calibrated Periopaper®. The amount of fluid collected was measured using a calibrated Periotron Economy®.
The results were as follows.
1) The measurement of the amount of GCF in children was proved to be possible with Periotron Economy®.
2) Any significant variance of the amount of GCF was recognized between the measurement within an interval of ten minutes.
3) There were no significant differences of the amount of GCF among the three measurement times even within the interval of one week.
4) The amount of GCF, PD, GB and GI of the permanent teeth showed higher values than those of the primary teeth. The DI of permanent teeth was lower than that of the primary teeth. There was no significant differences of the amount of GCF from normal gingiva between primary and permanent teeth.
5) There were significant correlations between the amount of GCF and PD, GB, GI respectively, while there was no correlation between the amount of GCF and DI, BR.
From the afore mentioned results the measurement of GCF with Periotron Economy® is considered to be helpful when periodontal disease in children is diagnosed.

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The aim of this study was to investigate the effect of the different components of salivary proteins on the formation of the acquired dental pellicle adsorbed onto the acid-etched enamel surface. We tried to establish a simple and convenient procedure for collecting respectively the 2-hour acquired dental pellicle from several subjects, and to obtain suitable amounts of the sample for the amino acid analysis of the 2-hour acquired pellicle.
The results obtained were as follows:
1. A suitable amount of samples was obtained by scraping with a scaler from the surface of 10 etched -enamel blocks (65×10×2mm), which were exposed for 2 hr to 6 ml of the supernatant of the centrifuged saliva.
2. Comparison of amino acid analyses between whole saliva and 2-hr pellicle of the same subject, confirmed rather consistent amino acid composition of 2-hr pellicle obtained from different subjects having different amino acid composition of the whole saliva.
3. The results of amino acid analyses of 14 subjects indicated that the 2-hr pellicle samples obtained from 12 respective subjects were rich in glycine, glutamic acid and proline, while the samples obtained from 2 other subjects were richer in serine than in proline.

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Gambir, one of rubiaceae planted in Indonesia, is used as a favorite food and is traditionally considered as an effective protector of dental caries in Southeast Asia. A dried gambir, called catechu, containing much of catechin, one of the tannins, has been used as an astringent material for the mouth. In this study, the aqueous extract of gambir was examined for the inhibition of the synthesis of insoluble glucan (ISG) synthesis and the growth of mutans streptococci (MS)in vitro.
Gambir aqueous extract inhibits ISG synthesis by glcosyltransferase in MS and it is speculated that the principal ingredient which inhibits the glcosyltransferase activity is most probably tannins.

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The purpose of this study was to investigate the epidemiological research of periodontal disease in 357 junior high school students, living in Hiroshima, Japan.
The gingival index(GI: Löe and Silness), plaque index(PlI: Silness and Löe), probing depth (PD) and bleeding index(BI) were recorded on the maxillary right first molar, right second incisor, left first premolar, mandibular left first molar, second incisor and right first premolar. The PD was measured every 0.5 mm for the six teeth. The BI on probing was also recorded.
The results were summarized as follows.
1.89.9% of the students exhibited gingival inflammation as indicated by more than 0.1 of the average GI.82.1% of the students exhibited mild inflammation, and 7.8% of the students exhibited moderate inflammation. Normal gingiva was indicated by less than 0.1 of the GI accounted for 10.1% of the students. There were no significant differences in the distribution of the GI between boys and girls. Gingivitis at the anterior teeth statistically higher than that of other teeth.
2. The PlI score in boys was higher than that of girls, whose PlI score tended to decrease in proportion to their grades. The PlI score in second grade boys was higher than that of first grade and third grade boys. The PlI score in the anterior teeth was statistically higher than that of the premolar and molar teeth.
3. The PD score indicated a peak of 1.0 and 3.0 mm in the anterior teeth and a peak of 1.5 and 3.0mm in molar. There were no differences statistically between boys and girls and among the grades.
4. The BI score in girls was statistically higher than that of boys and the gingiva in girls tended to bleed easily on probing.
5. The GI score in boys increased according to the PlI score, but the GI score in girls rather increased although the PlI score decreased in proportion to their grades.

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We surveyed unerupted primary teeth using 9,128 patients who were registered at the Pediatric Dental Clinic of Hokkaido University Dental Hospital. We found ten cases with unerupted primary molars. The ten patients consisted of five boys and five girls, aged from 3 years and 4 months to 8years and 3 months. All of them had unerupted teeth in their molar regions, i. e. second primary molars, in which, half were in mandibular and the other half in maxillary region. The Clinical features were examined on following guidelines;
A. Is there anything disturbing primary tooth eruption?
B. Is there dislocation of primary molars or/and their successors?
C. Is the space available for the eruption of the primary molar?
D. What is the eruptive direction of the primary molar?
Two cases had the pathological abnormalities which disturbed the primary molar eruption, one having a cyst and the other a tooth-like calcified object. Radiografic examination revealed that adjacent premolars were found in six out of the ten patients, but no premolars in four cases at the time of their first visits.
Severe dislocation of the second primary molars and second premolars were found in two cases, one case had a reversed position of the primary molar and its successor and the other had dislocation of the second premolar between the roots of the second primary molar and the first molar.
Four patients had space loss for the eruption of the primary molar, and six had enough space, although one of them lost her eruptive space due to the ankylosed primary second molar.
We made a protocol for therapeutic procedures base on the previous guidelines and found that the protocol was useful for making therapeutic plan for primary teeth molar impactions.
In eight cases excluding the two cases with extracted primary molars because of severe impaction, a follow-up study revealed the prognosis of unerupted primary molars as follows; in four cases, the primary second molars had erupted, in two cases, the impacted teeth were extracted because of invasive carious lesions, one case was extracted because of orthodontic problem, and one were unkown.
Two uneruptied primary molars which showed severe dislocation were extracted based on the protocol. After extraction of the primary molar, one successor erupted normally, and the other premolar grew normally in the adjacent bone.
We also discussed about the developmental stage of premolars from its predecessor and it might be an important factor related to the occurrence of primary molar impaction.

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Initial patients who visited the Pediatric Dentistry Clinic, Okayama University Dental Hospital in the last 10 years were investigated to understand the actual conditions of the patients and fulfill the dental requirements in our community. The following results were obtained;
1. The number of patients who visited our clinic for the initial appointment during the period from 1984 to 1993 were 10329. The number of patients has increased from 1984, but tended to decrease after 1990, year by year.
2. The number of infants under two years old reduced with the year.
3. Children with chief complaints of dental caries and pain have decreased. In contrast, children with consultation regarding preventive or orthodontic treatment have been increased.
4. Children with caries experience or severe caries have decreased.
These results suggest that environment surrounding children's oral status has changed with elevation of their caretaker's view of oral health and improvement of their caries status.

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The subjects of this study were 3,003 patients (1,410 boys and 1,593 girls) visited the pediatric dental clinic of the Tsurumi University Dental Hospital. The incidence of dens evaginatus (incisive tubercles of the anterior teeth and central cusps of the posterior teeth) of the permanent teeth was retrospectively surveyed by using the X-ray films and the oral examination records. The clinical management was suggested based on this survey. The results obtained were as follows:
1) Seven patients (0.23%) (2 boys and 5 girls) showed incisive tubercles. Eighty-eight patients (2.93%) (32 boys: 2.27% and 56 girls: 3.52%) showed central cusps. One patient showed both kinds of dens evaginatus.
2) Eight incisive tubercles were detected. Among them 2 cases were found in the upper central incisor and 6 cases were found in the upper lateral incisor.
3) Two hundreds and thirty-five central cusps were detected. Among them 234 cases were found in the premolar and one case was found in the molar. The numbers of central cusps observed among the premolars were respectively 96 lower second premolars (41%),71 lower first premolars (30%),37 upper second premolars (16%) and 30 upper first prmolars (13%).
4) The number of central cusps in the maxilla was 67 (28.6%) and in the mandible 167 (71.4%).
The incidence of central cusp in the latter was 2.5 times as much as in the former. The number of central cusps in the left side of the arches was 119 and the number in the right side of the arches was 115. Regarding the incidence of central cusps, no significant difference was observed between the left and right sides.
5) The average age of the patients having central cusps which were detected by means of oral examinations was 10 years and 5 months.
6) X-ray detection of central cusps was possible even prior to eruption of the premolars. The average age of such patients detected by the X-ray examination was 8 years and 5 months.

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In order to examine whether an immune reaction would take part in the process of physiologic root resorption of the deciduous teeth, changes in the titer of serum antibodies to dentin were measured in five young dogs with deciduous teeth, from the time prior to physiologic root resorption to exfoliation.
Dentinal components of the initially extracted deciduous teeth from each dog, as antigen, were prepared by immersing in 6M Guanidine HCl and EDTA solution. Serum samples and radiographs were taken from each dog from prior to the start of physiologic root resorption, and weekly thereafter. The process of physiologic root resorption and exfoliation of the deciduous teeth was confirmed by radiographic and oral examination. An ELISA was used to quantify antibody titers in the serum samples. The amount of specific IgG antibodies in any one serum sample was determined by comparison of the sample optical density with the background.
The titer of serum antibodies to the dentin changed during active root resorption. It tended to drop when physiologic root resorption started and active root resorption continued, and tended to return to baseline, the level of antibody titers prior to the beginning of physiologic root resorption, after all of the deciduous teeth were exfoliated. The results of this study suggest that specific immunological changes are involved during active root resorption, and the existence of circulating autoantibodies to the tooth root antigens in dogs suggests that immunological mechanisms may play a role in physiologic root resorption of the deciduous teeth.

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The aims of this study were to investigate whether the occlusal force of preschool children could be measured with a pressure-sensitive sheet known as the “Dental Prescale” (Fuji Photo Film Co. )and, if possible, tthen o compare the occlusal force of the early stage of the deciduous dentition with that of the late stage. One hundred ten children(59 boys and 51 girls, age 2.6-5.9 years)were subdivided into 4 groups according to Hellman's dental age classification; 1. IC (n=20),2. Early Stage II A (less than 4.5 years, n=34),3. Late Stage II A (more than 4.5 years, n=44), and 4. II C (n=12). The maximum occlusal force of each subject in full intercuspation was recorded with the “Dental Prescale”.
The percentage of children in each group whose occlusal force was able to be successfully measured were,30% in IC,59% in early stage II A,93% in late stage II A and 75% in II C. The data obtained in early stage II A in this study were compared cross-sectionally with the data obtained in late stage II A. The occlusal force and the area of occlusal contact increased from the early to the late stage of the deciduous dentition.
These results suggest that the occlusal force of preschool children after early stage II A can be adequately quantified with the "Dental Prescale", and that there are clear increases in the occlusal force and area of occlusal contact from the early stage to the late stage of the deciduous dentition. Measurements could not be obtained, however, in 70% of the IC group and 41% of the early stage II A group because the Dental Prescale sheets were too large. We therefore recommend that smaller sheets be produced in order to measure the ccclusal forces of children under 4.5 years of age.

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The purpose of this study was to clarify the anatomical forms and occurence of accessory foramina. The pulp chamber floors of 85 permanent molars obtained from 11 adult beagle dogs were examined histologically by optical microscopy. The results were based on a comparison between matured and immatured permanent teeth. The following conclusions were obtained.
1) Dentine in the pulpal chamber floor of the matured permanent molar was separated into two layers by terminal line, but in the immatured permanent molar dentin, this two layer structure was not detectable.
2) Sixty-six accessory foramina were observed in 50 molars (58.8%) out of 85 molars with an average of 1.3 per teeth. There was no significant difference in occurrence or number of accessory foramina.
3) Accessory foramina were classified into five patterns. Accessory foramina which opened to furcation area were most frequent (47.0%). The percentage of accessory foramina which penetrated into the pulpal floor (10.6%) was significantly lower than that of the non-penetrated foramina (89.4%). Significantly more penetrated foramina were observed in the immatured permanent molars than in the matured permanent molars.

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In order to asses histopathologically the changes that occur when teeth that have fallen out are replanted in the cavity wall of alveolar sockets damaged by trauma, we used the immature second maxillary incisors of dogs, and after they had fallen out, subjected the alveolar bone proper of the cavity wall of the alveolar socket to mild and severe damage, and conducted a replantation experiment. We prepared undecalcified standard horizontal continual ground sections and made comparative observations using microradiograhy, fluorescence microscopy, and polarization microscopy, and also included stanardized roentgeography and clinical findings.
1) When there was mild damage to the tooth, superfical resorption was observed in a portion of the root, and cement fomation was noted around the entire cicumference of the root. Inflammatory resorption and osseous ankylosis were observed in severely damaged teeth, and cement formation was irregular.
2) Extensive regeneration of tha periodontal ligaments was observed in mildly damaged teeth, but only a slight degree of periodontal ligament regeneration was detected in severely damaged teeth.
3) When we examind the periodontal ligament space around the replanted teeth in the horizontal sections, we found that it was of nearly uninform width in the mildly damaged teeth, but that its width had become irregular in the severely damaged teeth, and that its width had become slightly narrower.
4) Examination of the periodontal ligament space along the axis of the tooth showed that it was in the form of a functional hourglass in tha mildly damaged teeth, but that its width had become irregular in the severely damaged teeth and its functional shape had lost.
5) New laminar bone fotmation was observed in the perialveoar bone in mildly damaged teeth, but bony trabeculae had intermingled in the severely damaged teeth and had formed irregulaly.
6) Assessment of root formation revealed no abnormalities in the amount of root formation in the mildly damaged teeth, whereas root shortening and infraversion were noted in the severely damaged teeth.

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The purpose of this study was to investigate electromyographically the reflex control of the oral sensation on sucking movements in infants and adults. During bottle feeding in infants, the activities of the masseter and the suprahyoid muscles were recorded, and they were altered depending on the flow quantity of the nutrient milk. The activities of muscles being recorded were enhanced and the cycle duration of the movement was prolonged when the milk flow was increased.
During simulation of bottle feeding in adults, the electromyograms (EMGs) of the muscles and the tongue movements, recorded by the fluorograph (X-ray TV system), were observed to be nearly similar to those during the bottle feeding of infants. In adults, the EMG activities of the muscles were also enhanced by increment of the milk flow.
Local anesthesia was performed on the adults to investigate the effects of oral sensation on the simulated sucking movements. The changes of the EMG activities were analysed during simulated movements, after the local anesthesia had penetrated into the periodontium of the upper and lower incisors and canines, the hard palate, and both the upper and lower lips. After the anesthesia of the palate and/or the lips, the EMG activities of the suprahyoid muscles decreased during movements. The activities of the masseter muscles conversely increased, after the anesthesia of the lips. After the palate and the lips were anesthetized, inspite of increment of the milk flow, the activities of the muscles being recorded were not enhanced.
These results indicate that the sucking movements are controlled by oral sensation. It is also considered that the oral sensation from the palate and the lips facilitates the activities of the suprahyoid muscles which have been elucidated to play more active role in the sucking movement than the jawclosing muscles.

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The purpose of this study was to examine the constituents of crowding permanent dentition by longitudinal changes from stage II C of Hellman's dental age to stage IV A of the dental arch form and craniofacial morphology. The dental arch form was analyzed using dental casts, and the craniofacial morphology was analyzed using the roentgenocephalometric films. The subjects were divided into two groups by the level of arch length discrepancy of permanent dentition at stage IV A of Hellman's dental age. The two groups were classified into the normal dentition group (NDG) and the crowding dentition group (CDG). The NDG was comprised of 15 subjects, and the CDG of 11 subjects. The findings were as follow; 1) The mesio-distal lengths of maxillar or mandibular in the CDG tended to be short in comparison with the length in the NDG after stage III A.2) The axial inclination of the incisor in the CDG tended to be small in comparison with the axial inclination in the NDG after stage III A.3) There was a significant positive correlation between the arch length discrepancy and dental arch width at stage II C. The dental arch length and arch perimeter after stage III A related to the arch length discrepancy with a significant positive correlation. In contrast, there was a significant negative correlation between crown width and arch length discrepancy at stages III A and IV A.

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In order to improve the trajectory of tongue movement, increase tongue muscle strength and improve the coordination of the lips and other organs during swallowing, we developed a fixed tongue exercise in which oral functions are taken into consideration. Using the monitoring system developed by Kawashima, we measured with an ultrasound system the time required for various tongue movements and with a strain-gauge pressure transducer the tongue pressure.
Using the data obtained, we evaluated the reproducibility of fixed tongue exercise movements and obtained the following results.
1. Analysis of the ultrasound images revealed no difference in the duration of tongue movement among the subjects, and the data obtained when the same experiments were performed at one week intervals for three weeks or 10 times in one day varied little for each subject. Also, the time required for each movement in a series of cyclic tongue movements differed among the subjects.
The duration of downward movement but not the time requierd for upward contact or downward contact or the duration of upward movement differed between experiments performed at one-week intervals. When the exercise was repeated 10 times in one day, the time required for downward contact varied whereas the time required for upward contact and the duration of upward movement or downward movement did not.
2. In the tongue pressure measurements performed using the straingauge pressure transducer, differences were observed among the subjects in the maximum tongue pressure, the time required for pressure generation, the product of these two, and the pressure disappearance time, but not in the maximum tongue pressure duration. Moreover, the values of the first three of these parameters differed markedly and the tongue pressure disappearance time and the maximum tongue pressure duration differed slightly between experiments performed at one-week intervals. The values of none of the above mentioned parameters varied markedly during the repeated test.

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The purpose of this study was to investigate the influence of ultrasonic washing with 70% ethylalcohol on the resin adhesion to the bovine dentin.
The labial surfaces of 46 bovine mandibular incisors extracted and frozen in physiologic saline were used. Two adhesive treatment groups were prepared: the AB 2 Group (All-Etch, Primer A and B, Dentin/Enamel Bonding Resin: Bisco Inc. ), the SDL Group (10-3 solution, Superbond Primer, Superbond D Liner: Sunmedical Co. ). The composite resin used in this study was Clearfil Photo Anterior (Kuraray Co. ). Final polishing of the dentin surface was carried out with 600-grit wet silicon carbide paper. The cleaning efficacy of the one-minute ultrasonic washing with 70% ethylalcohol on the ground and polished dentin surfaces was observed in the SEM. The shear bond strength was tested and the test surfaces of the dentin and the resin specimens were observed in the SEM. Data were compared with the results on the nonalcohlol-washed dentin which were previously reported.
1. After the one-minute ultrasonic washing with 70% ethylalcohol, some of the dentinal tubules were found to be opened.
2. In the comparison of the bond strengths of the non-thermal cycled groups with those of the thermal cycled groups, in the AB 2 non-alcohol-washed groups, the bond strength of the thermal cycled group was significantly higher than that of the non-thermal cycled group.
3. In the comparison of the bond strengths of the non-alcohol-washed groups with those of the alcoholwashed groups, in the AB 2 non-thermal cycled group and the SDL thermal cycled group, the bond strengths of the alcohol-washed groups were significantly higher than those with the non-alcoholwashed groups.
4. As for the fracture modes between the dentin and resin, in the AB 2 thermal cycled groups, the percentage of the adhesive fracture of the alcohol-washed group was significantly higher than that of the non-alcohol-washed group and the percentage of the mix fracture of the non-alcohol-washed group was significantly higher than that of the alcohol-washed group.
5. There was the tendency to increase the bond strength by the one-minute ultrasonic washing with 70% ethylalcohol on the ground and polished dentin. In addition to the cleaning efficacy, the effects of the dehydration and the fixation of the dentin by alcohol might be considered.

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The change in the maxillary of inverted impacted supernumerary teeth inversion was observed with the use of radiographs.
The subjects were the 138 panoramic tomograms obtained from 42 children ranging from the deciduous dentition stage to the mixed dentition stage, taken for caries treatment or periodical examination. The existence of the supernumerary teeth had been definitely shown through panoramic tomograms.
The results were as follows:
1) The invertde supernumerary teeth were classified into two groups, “The movement-type” and “The non-move-type”.
2) In “The movement-type”, when supernumerary teeth have shifted into the jaw involved from six to seven years olds.
3) In “The movement-type”, it showed a marked trend while that the formation of the root was in progress, the formation of the root had a tendency to be slow in “The non-movement-type”.
4) In “The movement-type”, it showed a marked trend that the position of the supernumerary teeth when they were found in the beginning existed near the nasal cavity side.
5) In “The movement-form”, the adjoining central incisior on the side with the supernumerary teeth had a tendency to erupt earlier than on the side with the non-supernumerary teeth, and when the supernumerary teeth shifted into the jaw connesponding to the eruption time of the adjoing centralincisior.

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The purpose of this study was to find out the factors influencing the clinical sedative effects of oral diazepam sedation.
The subjects were 45 normal healthy children aged from 1 to 8 years, who received dental treatment under oral diazepam sedation (the dose of 0.3 mg/kg oral diazepam). They were divided into two groups on the basis of clinical evaluation of the sedative effects: one group consisted of 25 children, who were evaluated markedly effective or effective by comparing with the bahavior during dental treatment of those without the oral sedation (Effective group). The other group of 20 children, who were evaluated poor effective or ineffective by comparing with the behavior during dental treatment of those without the oral sedation (ineffective group).
The influencing factors were determined using a statistical analysis Quantification Type II. Sixteen factors were analyzed, these being his/her age, sex, character, experience of serious illness, experience of emergency dental care, baseline behavior (behavior during dental treatment without the oral sedation), the number of times of behavioral modification training before the dental treatment, and so on.
The results were summarized as follows; Five factors were determined as factors influencing the clinical sedative effects of oral diazepam sedation. The ineffective group had the following character; They were under 2 years old, disobedient children, having experienced of emergency dental care, having received behavioral modification training over 6 times, and exhibiting combative or violent rejection by comparing them behavior during dental treatment without oral sedation.

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Shwachman syndrome starts from infantile diarrea and is followed by congenital exocrine pancreatic, myelopathy, and ateliosis. The results of the general and oral examinasion of the present cace are given here.
1) The patient was a 10-year 8-month old boy with congenital exocrine pancreatic insufficiency and congenital neutropenia.
2) The height of the patient was 111 cm and his weight,22 kg at the first examinasion, these values being less than nomal.
3) Dental findings indicated enamel hypoplasia of the primary and permanent teeth, gingivitis and mobility of the lower incisers.

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A group of numerical abnormalities among sex chromosomal aberrations found in females, which is characterized by an excessive number of X chromosomes such as females with XXX chromosomes (triple-X females), females with XXXX (tetra-X females), or females with XXXXX (penta X females) is collectively called the poly-X syndrome. Since Jacobs et al. (1959) referred to- a patient with this syndrome as a “super female”, various cases have been reported. In Japan, however, there has been no report on the oral findings relating to this syndrome but a case of triple-X female was reported by Miura et al.
The patient of this case was a female child at the age of 16 years and 5 months who had been diagnosed to be a female with XXXX chromosomes (tetra-X female) within the poly-X syndrome. She was shown proved to have congenital heart disease, microseme, a shorter body height, the mental retardation and was underweight. As to the oral findings, congenital absence of maxillary bilateral lateral incisors, maxillary left lateral second premolar and mandibular bilateral second premolars, and large mesiodistal tooth width, as well as lower palate and progenia were observed.

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