The aim of the present study was to evaluate the existence of the Herpes Simplex Virus (HSV) in the saliva. HSV rarely evokes herpetic gingivostomatitis and herpetic labialis with an intensive mucosal manifestation in healthy pediatric patients. To detect the HSV, rapid and sensitive Polymerase Chain Reaction (PCR) was employed. At pediatric outpatient clinic of Hokkaido University Dental Hospital, asorbent cotton swabs were randomly dipped into the saliva of 241 healthy children (aged from 0 to 14) who had no symptoms of gingival or mucosal inflammation.
The rapid and sensitive PCR method revealed that HSV was distributed among healthy children in the pediatric outpatient clinic, showing the etiological significance.
The results were as follows:
1) HSV positive findings were revealed in 17.0% of the total samples from healthy children with no manifestation.
2) HSV positive findings were revealed at 0% in both 1 and 2 year old children and they had significantly lower rates than those of the other ages.
3) Investigating the evidence of HSV in siblings revealed that the HSV-positive rate detected in all siblings in the same family was not significantly different from the rate found in one of siblings in the same family.

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The purpose of this study was to determine whether the jaw closing muscle activities during jaw clenching were influenced by the sleeping posture of children.
Five children with deciduous dentition and three adults participated in this study. The subjects were asked to perform three different motor tasks voluntary jaw clenching while sitting, lying on their backs and on their sides. Electromyograms were recorded from the masseter muscle and from the anterior part of the temporal muscle, unilaterally.
There were no significant differences among these three different positions with respect to the activities of the jaw closing muscles during jaw clenching in either the children or the adults (ANOVA, p>0.05).
Our results indicated that the phasic motor unit activities of the jaw muscle EMGs were not influenced by the sleeping postures of children.

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The purpose of this study was to clarify the change of chewing movement in the process of mastication. The food sample used in this study was jelly, The texture of which getting to changes as mastication progresses. The subjects were divided into two groups according to dental age: the primary dentition group (3 boys,3 girls) and the permanent dentition group (7 women). The reference point was the lower incisal point. All the chewing cycles were divided into the early, middle and late period. Evaluation of the chewing movement according to the masticatory process was made using the following parameters; terminal position, maximum opening distance, maximum lateral distance, duration of chewing cycle, opening phase and closing phase. These aspects were compared between the two groups.
The results were as follows:
1. The terminal position became closer to the intercuspal position as mastication progressed in both children and adults.
2. The maximum opening distance became shorter as mastication progressed in both children and adults.
3. The maximum lateral distance became smaller as mastication progressed in adults, while there was no such trend in children.
4. The duration of the chewing cycle and the closing phase became shorter in children, while there was no change with the chewing rythm in adults as mastication progressed.

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We investigated three dimensional treatment changes of the maxilla in children with the deciduos crossbite who visited the Pedodontic Clinic of Kyusyu University. The appliances we used for treatment were the chin cup, the FKO, the lingual arch and the maxillary protracing bow appliance. We measured the maxillary dental arch, the area and the volume of the palate using the plaster casts before and after treatment, and compared the effects of these 4 appliances.
The result were as follows:
1) The dental arch form of the chin cup and FKO group did not change, but the lingual arch group caused the dental arch to become longer by an increase of dental arch circumference and length, and the maxillary protracing bow appliance group caused it to become flatter by a decrease of them.
2) The chin cup, the FKO and the lingual arch group caused an increase to the total area and the volume, and the maxillary protracing bow appliance group caused a decrease. Moreover the anterior part of the chin cup and the FKO group showed an increase in the area of the palate, but a decrease in the volume, and the posterior part of the maxillary protracing bow appliance showed a slightly increase in the area of the palate, but a decrease in the volume.
3) From the result of the dental arch width, the chin cup, the FKO, the lingual arch and the maxillary protracing bow appliance group showed small change rate, so there were no differences between these 4 appliances.

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This study had two goals. The first was to determine whether gustatory sensitivity alters during the aging process. The second was to examine how the intake of a tastant in infancy might influence gustatory sensitivity later in life. Behavioral (two-bottle preference tests) and electrophysiological (chorda tympani nerve recordings) methods were used on Sic: ICR and SAM P-1 mice.
The Mice were tested using both methods at 10,25 and 50 weeks of age.
The results were as follows:
EXPERIMENT 1. Decrease in gustatory sensitivity at in terms of behavior mice showed a age 50weeks to NaCl, HCl and Q-HCl. There were however no changes in gustatory sensitivity to sucrose at any age. Electrophysiologically, there was an increase in the NaCl response magnitude atage 50weeks.
EXPERIMENT 2. Responses of mice raised for the first ten weeks of life on distilled water or one of four tastants for the purpose of taste stimuli were obtained and compared. In terms of behavior, there was a decrease in gustatory sensitivity only with respect to those tastants which the mice were raised on.
Electrophysiology, no differences in responses were seen in any case. From the above findings, it was concluded that a decrease of the gustatory sensitivity related to aging is not a function of changes in peripheral taste receptor cells, but may occur in the central nervous system.

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The purpose of this histological study was to show the situation of poor resorption in the exposed root apex in the oral cavity in human deciduous incisors with severe apical periodontitis. The results showed abnormal resorption in the apical root dentin and partial repair by cementum deposition on the apical root dentin surface. It was suggested that resorption and repair of the infected root dentin took place in the early stage of the process on exposure of the root apex in oral cavity. Since the various reactions such as the defense mechanisms in vivo originated at the apical root and had resulted from excretion, it was thought that the realization of the exposed root apex needed considerable time and there were many environment factors which made up the situation of apical root, such as the level of microorganisms infection, the situation of apical periodontitis, the thickness of alveolar bone, the eruptive forces of permanent successors and so on.

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In order to clarify the situation concerning dental disease, dentition, abnormal occlusion, and eating behavior of young children, we compared the results of a basic survey on physical and nutritive conditions of young children in Tokyo conducted in November 1996, which involved 1,096 children aged from 3 to 6 who attended 6 nursery schools and 6 kindergartens located in Tokyo, with results of the same survey and similar surveys conducted in 1987. We obtained the following results.
(1) In the 1996 survey, the percentage of the children with df increased with age, reaching 89.2 for the 6 year olds. This tendency was also observed in tke 1987 survey, The average number of df teeth in the 3 or 4 year olds in the 1996, survey was lower than that in the 1987 survey.
(2) A high percentage of the children who consumed sweet drinks frequently had dental caries.
(3) Regarding dentition and abnormal occlusion, deep bite, edge-to-edge occlusion and maxillary protraction were observed fairly frequenty in the 1996 survey. Comparison with the 1987 survey results showed that the number of young children with maxillary protraction, cross-bite or deep bite had increased, but the number of young children with anterior cross-bite, edge-to-edge occlusion or open bite had decreased.
(4) Regarding eating behavior, the mothers of more than half of the 3 and 5 year olds in the 1996 survey answered “yes” to the question: “Does your child like to drink milk or any other kind of drink during mcals?” In addition, the number of young children who “hate to eat food which is difficult to eat” was higher in the 1996 survey than in the 1987 survey.

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Children who came to this hospital for tooth injury were referred to a pediatric dentistry clinic but none with trauma due to jaw fracture, to oral surgery of for and long-term follow-up.
This report is based on a survey which shows that 945 patients, under 12 years of age, were referred to the Department of Oral Radiology, Osaka Dental University from 1985 to 1994.
The results were as follows:
1. The distributions of diseases decreased in the order of cysts, traumas, inflammations, tumors, diseases of the salivary grand, diseases of temporomandibular joint, and other items.
2. The ratio of boys to girls of pediatric trauma patients was 1.6: 1, and the ratio of the clinical and radiographic finding for fractures was 1.4: 1. All the patients, under 12 years of age, were referred to our hospital from 1985 to 1994.
3. Most of the boys were in the period of mixed dentition, and the girls mostly in the period of primary dentition.
4. Most injuries occurred in spring and summer, and the fewest in winter.
5. Most patients were referred to our hospital by a medical hospital.
6. The cases which were referred to this hospital within 1 week, involved 86.7% in trauma, and 85.3% in fracture.
7. Trauma and fracture in most cases were due to falling.
8. Most regions of the jaw fractures involved the mandible.
9. For 12 of the 74 jaw fracture cases that involved the germs of permanent successor on the region of the jaw fractures, a long-term follow-up study has been conducted.
10. On cases that involved the germs of the permanent successor on the region of the jaw fractures, there was anomaly of the location of the teeth, retarded eruption, and anomaly of the root formation.
Long-term follow-up should be conducted for children with trauma because of the germs of the permanent successor in the jaw. In particular, when there are the germs of the permanent successor in the region of the jaw fractures, it is necessary to conduct a long-term follow-up till the permanent successors have erupted.

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The nationwide survey on the mesiodistal crown diameters of the primary teeth and the primary occlusions was reported by the Japanese Society of Pediatric Dentistry (JSPD) in 1993. The report stated that the frequencies of interdental spaces and the primary occlusions were markedly different from the results described thirty years ago by Ono, although no differences were observed in the mesiodistal crown diameters of the tooth crowns and the size of dental arches.
The aim of this study was to clarify the reason for these discrepancies. As we considered it to be attributable either to the difference of the dates of the investigations or to the difference of the selected standards of specimens between the papers, we examined new patients who had visited Kanagawa Dental College Hospital, Department of Pediatric Dentistry from 1991 to 1992. The selection of specimens from dentition casts was performed according to the standards 1 and 2 established by the JSPD.
As the result of this research, it was found that the differences of the frequencies of the interdental spaces and of the terminal planes between the data of the JSPD and of Ono were dependent on the standards employed.
The frequency of observing the occlusion of primary canines in maxilla and mandible decreased in the order of types I, II and III, regardless of the selection of standards employed.

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One hundred forty five patients making their initial visit who were referred from the Okayama University Medical Hospital to the Pediatric Dental Clinic, Okayama University Dental Hospital during the period from 1992 to 1996 were investigated to understand actual conditions of these patients. The following results were obtained; 1. The number of these patients tended to increase, year by year.2. The ages of these patients were distributed frequently between 6-12 years old.3. A high portion of patients was referred with chief complains of dental caries and pain. In contrast, only a few patients visited our clinic for consultation concerning preventive treatment.4. Twenty seven percent of the patients showed no caries, while,20% of patients had severe caries.5. Only 22.1% of these patients visited our clinic regularly after the initial visit. Other patients discontinued visiting due to various reasons. These results suggest that we have to treat them according to their particular conditions of general diseases and also that continuous dental checking from early age is important.

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A new morphological study was designated to examine the function of odontoclasts. Odontoclasts were isolated from bovine deciduous tooth roots where resorption of the tooth was taking place, and they were cultured on bovine whetted dentine slices. After culture, they were stained with FITC-labelled phalloidin which selectively binds to F-actins, and the activity of tartrate-resistant acid phosphatase (TRAP), a marker of osteoclasts, in the cells was also stained by an established histochemical method.
Many similarities were observed between the cultured odontoclasts and osteoclasts: the odontoclasts, like osteoclasts, were large in size, and have many nuclei, a clear zone (or ruffled border) in which F-actin is concentrated, and a strong TRAP activity. They form absorption lacunae on the surface of the dentine slices. The clear zones of the cultured odontoclasts were observed as ring-shaped or arch (broken ring)-shaped bands. The absorption lacunae formed by the odontoclasts with ringshaped clear zones or by the cells with arch-shaped clear zones were unilocular or multilocular, respectively. The non-broken side of the ring of arch-shaped clear zones corresponded to the portion of resorption front in the dentine slices. These results, together with those of our previous study, suggest that (1) odontoclasts have a close relation to osteoclasts, (2) odontoclasts with ring-shaped clear zones have a higher resorptive activity than those with arch-shaped clear zones, and (3) the present method used for staining F-actins in clear zones in useful in examining the activity of odontoclasts.

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I investigated the effect of the base of the root during tooth eruption.3 week old male Wistar rats were fed a normal diet, or fed a diet low in vitamin A, and the amount of tooth eruption of the mandibular incisors was measured. The base of the root was examined with the immunohistochemical method.
At 6 weeks there was considerable difference in eruption between the experimental animals and the controls (p< 0.001-0.01).
Proliferating cell nuclear antigen (PCNA) positive cells could be seen among all of the cells constructing the base of the root. There was also a significant difference in the rate of the PCNA positive cells from 7 weeks (p< 0.001-0.01). The epidermal growth factor receptor (EGFR) was expressed in the odontoblasts, pulp fibroblasts, periodontal ligament fibroblasts, dental follicle, blood vessels, ameloblasts and stratum intermedium of the experimental animals. The epidermal growth factor (EGF) was expressed in the cytoplasm of these cells.
These results suggest that EGF may be an epithelialmesenchymal signal when the inner enamel epithelium differentiates into ameloblasts, and the preodontoblasts differentiate into odontoblasts. Because cell proliferation at the inner enamel epithelium, stratum intermedium and preodontblasts was restricted in the rats deficient in Vitamin A, these cells may be important in tooth eruption.

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The purpose of this study was to follow longitudinal changes in the periodontal conditions of junior high school students. The Oral Rating Index was used, which is designed for screening periodontal conditions. The survey was conducted on 117 students enrolled from a school in Hiroshima, Japan. The study took place over a period of two years. The percentages of negative assessment (ORI of -1and -2) at grade 7,8 and 9 were 19.7,30.8 and 45.3, respectively. The periodontal conditions became worse according to increased grade. The mean ORI scores of grade 7,8 and 9 were 0.38, -0.13and -0.26, respectively. There was a significant difference among the three grades (p< 0.001). As for gender, the mean ORI score of the boys was higher than that of the girls at grade 7 (p< 0.01). On the other hand, the mean ORI score of the girls was higher than that of the boys at grade 9 (p< 0.05). Comparing periodontal conditions at grade 7 and 9,52.1% of the students became worse, comprising 73.7% of the boys and 31.7% of the girls.32.1% of the students were assessed as being in poor condition at grade 9, though they were assessed as being in good condition at grade 7.60.9% of the students at grade 9 remained poor condition for the two years.
In conclusion, the results indicate that the periodontal conditions worsen with increased grade. This suggests that early oral hygiene instruction should be individually given to students who, through screening, are assessed as having poor oral health, in order to cure them of and protect them from periodontal diseases.

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We performed dental examinations in accordance with the Community Dental Health project at five institutes for the handicapped in Kitakyushu City. Based on the results of the annual dental examination of mentally retarded children at 3 institutes over a period of 3 years, we analysed the change of the ratio of caries teeth, the ratio of filled teeth and the ratio of the acceptance of the pit and fissure sealant and the improvements of the plaque attained on the surface of upper central incisor as well as gingivitis. We also discussed the results of the dental treatment after the recommendations made in accordance with the initial examination.
The results were as follows.
1. The ratio of caries teeth decreased and the ratio of the acceptance of the pit and fissure sealant and the ratio of filled teeth increased during the 3 years.
2. The early care group which received dental care from birth had a lower ratio of caries teeth and the ratio of the acceptance of the pit and fissure sealant than both the non care group which had never gone to the dental office and the general practitioner group.
3. The severity of the gingivitis and the plaque attained were more noticeable in the other two groups than in the early care group at the first examination.
4. The number of the children who needed dental care decreased gradually.
5. The early care group accepted not only the caries treatment but also the preventitive services. Almost all of the children of the other two groups accepted only caries treatment.

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In clinical pedodontics determination of the occlusal function during growth in young children is an important task. In our first report we determined the optimal measuring conditions for clinical applications of a system comprising the DENTAL PRESCALE ®and the OCCLUZER ®- FPD 703 allowing comparatively simple evaluation of the occlusion.
In this study we concentrared on a comparative examination of the reproducibility, measuring the occlusal contact area, the average occlusal pressure, the maximal occlusal pressure, the biting force and effective pressure during continuous measurments or repeated application. The subjects in the study were 32 children with individual normal occlusion ranging from Hellman's dental age IIA (here an age under 4 years and 6 months was defined as early IIA phase and an age of over 4 years and 6months as late IIA phase) up to IIC. We also performed a comparative study of the average values classified by dental age and obtained the following results.
1. The average values obtained during continuous measurements, classified by the type of DENTAL PRESCALE ®, showed for all measuring parameters values of approximately 0-5% for both 30 R and 50 R, while for 30 W values of approximately 8-36% were observed.
2. The average values obtained for the coefficient of variation showed for all measuring parameters values of approximately 0-12% for both 30 R and 50 R, while for 30 W values of approximately 8-42% values were observed.
3. The occlusal contact area and biting force for 30 R and 50 R showed significantly higher values during the late IIA phase than during the early IIA phase.
4. Regarding the maximal occlusal and the effective pressure many measurements of 30 R and 30 W exceeded the pressure measuring range, but good results were obtained for 50 R.
The results described above suggest the necessity to consider reproducibility and pressure measuring range for each type. For an application to children of over 3 years multiple measurments using 50R and the average values were considered to be optimal.

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The dentin bonding strengths between composite resins and primary molars and premolars were investigated using two commercially available composite resin systems. The resins were adhered to dentin, and the shear bond strengths were determined. The fractured surfaces were observed by SEM. The findings of this study were as follows. The shear bond strengths between the primary molars and Multi-Purpose and between the primary molars and Liner Bond II were 10.1±4.8 MPa and 9.2±3.8 MPa, respectively. No significant differences (p<0.05) in shear bond strengths were found between the primary molars and resins used in this study. The shear bond strengths between the premolars and Multi-Purpose and between the premolars and Liner Bond II were 10.7±2.6 MPa and 12.8±3.11 MPa, respectively. No significant differences (p<0.05) in shear bond strengths were found between the premolars and resins. The results of two-way ANOVA showed that there was also no significant difference in the dentin bonding strength between the primary molars and premolars using these techniques.
SEM observation demonstrated that shear bond failures occurred at the resin-dentin interface in the majority of specimens showing adhesive failure and co-adhesive failure. No characteristic failure specific to primary molars or premolars was observed.

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The role of a University dental hospital in the community has seemed to vary through the background of change in disease structure and a decline in birthrate. The purpose of this study was to investigate the actual conditions of initial visit patients during the last 5 years (1992.1.1-1996.12.31)at the Pediatric Dentistry Clinic of Meikai University and to consider the countermeasures for the coming change.
1. The average number of the initial visit patients in a year was about 300 for the past 5 years.
2. The initial visit patients of 3-5 years of age amounted to 44% and patients of age 2 years and below patients coming for an initial visit amounted to 16% of all the outpatients. These ratios of the patients remained at a similar level throughout these years.
3. The children with dental caries and toothache as thier chief complaint have decreased. In contrast to this, those with consultation for the prevention and orthodontic treatment have increased gradually.
4. An investigation for the distance from the home to the clinic showed about 52% of all the outpatients were the within 5 km range.
5. The annual transition of the number of DMFT showed a tendency to ward decrease in dental caries.
6. The referral patients from the other medical institution accounted for 26% of all initial visit patients.
7. The number of handicapped children amounted to 69, which accounted for 4% of all initial visit patients.
These results suggest that the demand for the dental treatment in the community on the clinic was very high and variable, and we have to endeavor to provide a higher level of dental service.

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A survey was conducted to shed light on how often restraint therapy had been used for the treatment of pedodontic cases in our clinic.
The subjects were new patients who visited our clinic at the Department of Pediatric Dentistry at Nippon Dental University Hospital in Niigata, from 1989 to 1993. The findings were as follows:
1. Of the total 1,478 child outpatients,138 or 9.3% received restraint therapy.
2. The average age of the patients on their first visit was just 4 years. Those who were treated under restraint averaged 3 years and six months of age.
3. A check of the number of times the child subjects underwent restraint therapy revealed that the largest 40.6% (56 subjects) experienced this only once. The number of these patients tended to decrease with the increase in the number of times.
4. By type of restraint therapy, physical restraint was the most common and was used on 89 infants. This was followed by V. C. (voice control) or HOME (hand-over-mouth-exercise) on only 49 and partial physical control on 26, in decreasing order.
Based on these findings, it was concluded that less than 10% of the patients were given restraint therapy in our clinic and that the number of times this kind of procedure was used was held down to the minimum. Presumably this might have reflected the policy of the department of pediatric dentistry which emphasizes the importance of a good operator-patient rerationship. Every operator working in our clinic has been told to do without restraints as much as possible except for use as an emergency mesure.

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The objective of this study was to shed light on the personality traits of child patients on whom we had chosen to perform restraint therapy in the pedodontic clinic of the Nippon Dental University Hospital in Niigata.
For this purpose, Hayashi's quantification theory 3 rd family was used to analyze similarities found in the TakagiSakamoto juvenile personality test. The following conclusions were drawn.
1. Given the origin of the coordinates at the point where the degree of cumulative contribution surpassed 60%, three correlation axes were obtained. Eigenvalues stood at 0.3949 for axis 1,0.1410for axis 2 and 0.0997 for axis 3, and contributory ratios came to 39.5%,14.1% and 10.0%, respectively.
2. Axis 1 was interpreted as the correlation axis denoting the stability or instability of the personality, axis 2 denoting extroversion or introversion, and axis 3 denoting adaptability to the environment.
Based on these findings there was strong evidence of similarity in the categories such as an essential lack of self-control, anaclisis, and constitutional instability. This fact suggested that many of our subjects have these personal traits in common.

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In their studies Lecomte (1987) and Watanabe (1992) showed that the rates of clearance at the upper posterior buccal side in the mouth varied depending on the subject. The aim of this study was to investigate how the situation of the opening of the parotid duct changes during growth.
The situation of the opening of the parotid duct was evaluated with plaster model taken from the subjects (Total 24) with primary dentition (8), mixed dentition (8) and permanent dentition (8).
The opening of the duct for the permanent dentition was situated near the standard point (distal side of the first permanent molars), while on the other hand that for the mixed dentition was situated at the mesial side of the standard position. For the primary dentition, the location was at the mesial side of the standard point (distal side of the second deciduous molar).
The conclusion was that the opening of the parotid duct showed a tendency to move at the rear ward in the mouth during growth.

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The purpose of the study was to investigate the differences of the electromyographic (EMG) activities of the peri-oral muscles during suckling between breast feeding and feeding with two types of conventional artificial nipples. Forty-eight babies, who were born normally and healthy, participated in the study. The babies were divided into three groups based on the feeding methods; such as the breast feeding group (BRF: 28 babies, mean age: 13.9 wks), the round outform artificial nipple group (ROF: 11 babies, mean age 14.6 wks) and the elliptic outform with semilunar valves inside the nipple group (SV: 12 babies, mean age 13.9 wks). EMGs were induced from the temporalis (TM), masseter (MM), orbicular oris (OM) muscles and the suprahyoid muscles group (SM), while the EMG activities and the suckling cycle time were critically compared.
The following results were obtained:
1. There were no differences in the activity of the MM and the OM between the groups, but the BRF showed significantly higher activity in the TM and the SM than in the ROF group (p<0.05, p <0.01), and the SV group showed higher activity in the SM than in the ROF group (p<0.01) as well.
2. Total muscle activity of the four muscles also showed higher in the BRF and SV groups than in the ROF group (p<0.01, p<0.05).
3. The duration of the suckling cycle time was significantly longer in the SV than in the BRF and ROF (p<0.01).
4. During suckling movements babies showed biphasic suckling patterns; compression and suction phases, and the tongue showed peristaltic movements during both ROF and SV feeding. The EMG activity of the SM in SV group showed remarkably higher activity relating to compressing the nipple by the tongue and lowering the tongue for suction.
These findings suggest that the babies were able to intake milk from the round outform conventional artificial nipple with rather less efforts of the peri-oral muscles when compared to the breast and/or elliptic outform nipple with semilunar valves.

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In our previous report, the experimental trauma hitting the mandible of 4-day-old rats with a force of 3 N could effectively produced the enamel hypoplasia accompanying inhibited crystal growth. We hyhothesized that the serum albumin from experimentally induced localized trauma could saturate into the enamel matrix and thus inhibit the crystal growth. The purpose of the present study was undertaken to localize serum albumin using the immunohistochemical method and autoradiography of albumin labeled with ¹²⁵IT. rauma was given by hitting the mandibular incisor region of 4-day-old rats. Hitting was performed with by a force of 3 N. The rats were then sacrificed after 30-min,1 h,1 d and 1 W after being hit. The lower incisors were then removed together with the jaws and soft tissues. After fixing and demineralizing, paraffin sections were made 6μm thick. The ABC method was used for immunohistochemical staining. Goat anti-rat Albumin polyclonal antibody was used. The bound antibody was made visual by application of the DAB solution. Other sections were stained with hematoxylin and eosin. Albumin labeled with ¹²⁵I was injected into rats. The incorporation pattern of the labeled albumin into the enamel organ was observed 60-min after the injection, using autoradiography. Hemorrhage was observed from the peripheral of the tooth germ to the distal ends of the ameloblasts within 1 h after the hitting. Vacuolation was observed between the distal ends of the ameloblasts and the enamel matrix. Albumin was identified and localized in the outer layer of the enamel matrix adjacent to the detatched secreting ameloblasts, in particular corresponding to Tome's process, within 60-min after the hitting. Also, albumin was still remained in the matrix even at the period of mineralizing enamel. These results suggested that albumin saturated into the enamel matrix through the secreting ameloblasts after trauma, and albumin was then left and undegrade within the enamel matrix, and that would inhibit the crystal growth and consequently lead the hypocalcification of the enamel.

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Dental care for a Japanese boy with anhidrotic ectodermal dysplasia was performed from the age of 5 year-4 month to adulthood. The process of the dental care and the longitudinal change of the cranio-facial growth of this patient were studied. The patient had bilateral upper and lower primary canines which were peg teeth. His functional and esthetical problems were improved by wearing partial dentures, but both lower primary canines were lost by abnormal eruption or traumatic injury during the course of the dental care. The upper primary canines were restored using resin jacket crowns for correction of the crown form, and an overdenture for the upper jaw and a full denture for the lower jaw were worn.
The diagnoses of the occlusal height were made by linear analyses of the X-ray cephalometry, which comprised measurement of the dimension of each part of the facial bones on the co-ordinates. Since the height of the lower face was low due to absence of the alveolar processes, that should have been corrected by the dentures so as to improve the proportion of height of the facial bones. In particular, the acceptable occlusal height of the patient was maintained throughout the dental care by adjusting the ratio of the height of the lower face and the posterior portion or upper face.
Furthermore, a retrospective analysis for the cranio-facial growth was performed regarding the linear analysis values and the growth ratios. When the height and the growth ratio of the posterior portion of this patient were compared with the average Japanese children, they were smaller than the average. The growth ratio of the height and depth of the upper basal arch, and that of the depth of the lower basal arch were different from the average, but the growth ratios in other parts of the face were similar to the average, while the actual dimensions were smaller than the average.

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A case of epulis in a six-year-old female was reported here. It occurred in the gingiva in the upper left first molar region, with the upper left first molar not having come out yet. The upper right first molar had come out completely by then. There were no symptoms beside slight contact pain in the tumor. The tumor was removed surgically and histopathologically showed epulis granumatosa. The prognosis has been good, and the upper left first molar came out soon after the surgery. No recurrence has been observed to date.

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This paper reported that green pigmented deciduous teeth caused by hyperbilirubinemia could undergo light yellowish discoloration after a long period of time, and the bilirubin even in such yellowish teeth could be demonstrated with the light absorption analysis.
A one-year-old male with green pigmented lower deciduous central incisors was referred to Chiba Children's Hospital. At the first examination, a green and yellowish area was seen in the cervical 4/5part of the crown. Shortly after birth, extensive cephalohematoma as well as disseminated intravascular coagulation occurred followed by hyperbilirubinemia,20-59.6 mg/dl on the plasma bilirubin level. Based on oral findings and his history, clinical diagnosis of bilirubin-pigmented teeth caused by hyperbilirubinemia was made. Because of no visible symptoms other than the pigmentation, the teeth were clinically followed up without any treatment. Until 3 years and 5 months of age, the green pigmentation had gradually discolored to light brown and consequently to light yellow by the age of 5years.
The light yellowish deciduous teeth which shed naturally were examined and the following results were obtained.
1) With the ground section of the teeth, the pigmented band probably caused by bilirubin deposit was seen in the dentine using light microscopy.
2) Fluorescence was observed in the pigmented band by means of irradiation of 546 nm wave length light.
3) With spectrophotometric analysis (after SHIBATA, T. et al.1996), chemically extracted samples from pigmented teeth showed maximum absorption spectra at 450 nm wave length light, and after diazo reaction of the sample, they shifted from 450 to 540 nm. The absorption spectrum of the pigmented tooth samples closely paralleled that of normal ones to which bilirubin standard was added, with the former more enhanced than the latter.
Based on these findings, the presence of bilirubin was demonstrated even in light yellowish pigmented teeth. Pigmentation of teeth induced by hyperbilirubinemia was also found to pass over into various color stages, such as from green to light brown or light yellow.

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The patient was an 8 year 5 month old female child who had gingival hypertrophy and odontoparallaxia.
As for the oral findings, gingival hypertrophy was found on the permanent teeth. The tone of the gingiva was normal and had a hard elasticity on the upper incisal labial area.
The pathologic findings were as follows; the investing epithelium showed thickening, cornification and multiplication on the irregular epithelial protuberance. Cell components were sparse under the epithelium. The collagen fibrils showed thickening, fibrous bands and reticulo fibers. In addition, inflamation was observed as a cellular infiltration. Because this disease has an autosomal dominant gene and there are reports of recurrence, it is important to observe these cases rather carefully and over along period of time.

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Abstract: We experienced a case with a cluster of tumor like polypapilloma in the upper labium in a 6 year 11 month old girl who had generalized dermal hypoplasia and polyanomaly.
Before extracting these tumors, we tried to identify them as benign or malignant using both the common pathologic methods and the molecular biological examination including polymerase chain reaction (PCR). We also examined to identify the human papillomavirus of the specimens from the patient.
The results were as follows:
1. We finally determined these tumors as benign using pathologic method and molecular biological examination.
2. The molecular biological examination is one of the most useful methods for the detection of a small amount of virus, and its procedures are simple and rapid. In this case, we were able to apply this method to clarify the causative virus or micro-organism of the specimens from the patient.
3. In this study, we were not able to identify the type of HPV. These results suggested that the papilloma extracted in this case was a rare type because of being a non general benign HPV type accompanied by manifestation of generalized dermal hypoplasia and polyanomaly.

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