Fibroblastg rowth factorsw ere found to act as a growth fa ctorsf or fibroblasts. L ittle attention has been paid, however, to the effect of the other growth factors such as the effect of neurotrophins on fibroblasts. The aim of this study was to evaluate effbcts of neurotrophins (nerve growth factor-β(NGF), the brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3)), and the insulin-like growth factor-1 (IGF-I) on the proliferation of fibroblasts. Furthermore, we evaluated the effects of these four growth factors on the buthionine sulfoximine (BSO)- and vincristine-induced apoptosis of fibroblasts. When cultured in a medium containing 10% FBS, NGF did not affect the survival of fibroblasts at concentrations of up to 30μM after 24-72 h incubation. Under the experimental conditions employed in serum free, NGF did not affect the survival of fibroblasts, irrespective of concentration and incubation time. Similarly, BDNF and NT-3 were not found to affect fibroblast survival despite the experimental conditions. In contrast, the addition of increasing concentrations of IGF-1 resulted in a concentration-dependent potentiation of fibroblast proliferation without 'serum after 48 h and 72 h incubation. In the presence of serum, IGF- I potentiated the proliferation of fibroblasts after 48 h incubation, but not after 72 h incubation. Glutathione-depleted fibroblast treated with BSO underwent cell death. In addition, the anti-cancer drug vincristine inhibited the survival of fibroblasts. IGF- I, but not the three neurotrophins which attenuated the cell death of fibroblasts with vincristine in the absence of serum. In the presence of serum, however, the four factors examined failed to alter the cell death of fibroblasts with vincristine or BSO. These results suggest that IGF-I, but not NGF, BDNF, NT-3 may potentiate fibroblast proliferation.

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The purpose of the present survey was to investigate the attitude toward and consciousness of oral health which middle school students in Sendai have. The number of subjects was 3744. The questionnaires were filled out by the subjects during homeroom time. The results are summarized as follows.
1) 72.6% of subjects brushed their teeth twice a day in the morning and at night.
2) The rate of the subjects who had a daily sweet had intake was 32.3%, and 19% who drank sweet beverages daily.
3) Most of the subjects had made dental visits and 91% of them had visited dentists for the purpose of caries treatment.35.8% of the subjects had not wanted to go to the dentist for the reason that the dental treatment was painful, and they wanted painless treatment from the dentists.
4) About 30% of the subjects had been given tooth-brushing instruction and oral health guidance.
5) About 30% of the subjects had known that fluoride was effective on caries prevention. A few of the subjects had been given fluoride prophylaxis through topical application (7.6%) or mouth rinsing (4.3%).
6) Concerning the question of “What are the most important things to maintain oral health?” 80% of the subjects mentioned tooth-brushing as well as no intake of sweets.
7) The oral problems which the subjects were concerned with were dental caries, malocclusion, and nasal obstruction.
8) 37.3% of the subjects were familiar with the “8020” campaign.

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The Purpose of this paper was to investigate the recent trends of the first time patients who visited the Pediatric Dental Clinic of Tohoku University Dental Hospital. The records of five hundred and three patients who visited the clinic during the period from April 1996 to March 1999 were examined concerning the reason for the visit, medical history, oral health status, and the dental treatment as well as the preventive care performed before the first recall visit. The following results were obtained.
1. While the total number of patients slightly decreased compared to the reports of the 1980's, the number of one or two year-old patients increased.
2. Most patients visited for treatment of decayed teeth (43%), followed by dental health care (31%).
3. The proportion of the number of medically compromised patients to the all patients was 45%, and it increased compared to the past reports. The cleft lip and palate were the most frequent reasons and the percentage for all of the patients was 16%.
4. The mean dft scores decreased for all of the ages of 1-6 compared to the past reports.
5. Restoration with composite resin was the most common restorative treatment for both primary teeth and permanent teeth. The number of fissure sealed permanent teeth was greater than the total number of the restored permanent teeth.
6. Professional application of topical fluoride was performed on 30% of the patients and the lowconcentrated topical fluoride solutions for home use were administered to 20% of the patients. Both were mainly applied to the 1-2 year-old patients.
7. Dental health care program for the medically compromised patients from the early age of 1 or 2 has increased in our clinic.

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With regard to the serial changes in pH and the amount of sustained fluoride release in various types of condensation and filling materials with sustained fluoride release, the following results were obtained under various conditions.
1. Continuous sustained fluoride release was noted in the specimens immersed in 50 ml physiological saline, and marked decreases in pH were detected in some condensation materials.
2. Specimens immersed in 1,000 ppm ion concentration fluoride solution 5 days after irradiation showed Larger amounts of sustained fluoride release, in comparison with the specimens immersed in physiological saline.
3. Specimens, to which daily temperature changes between 4°C and 60°C were applied immediately after irradiation, showed lower pH values and increases in the amount of sustained fluoride release in comparison with the specimens immersed in 50 ml physiological saline.
4. Specimens immersed in 50 ml physiological saline, to which sand blast treatment was performed 5 days after irradiation, showed marked increases in the amount of sustained fluoride release.
These findings suggested that materials with sustained fluoride release continuously release fluorides, repeatedly recharging and releasing, according to temperature loading, and changes in the surface structure. It was speculated that the oral cavity with changes in temperature and pH is influenced in a similar way receives. It was therefore considered that topical application of fluorides to the smooth surface of the tooth crown after condensation and filling increases the amount of sustained fluoride release in the condensation and filling materials, and caries preventive effects on the immature permanent teeth are expected.

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The purpose of the present study was to investigate the effect of unerupted maxillary incisors on dentofacial structures comparing a group with unerupted teeth with a group with crowded teeth at Hellman's dental age IIIB. The group with unerupted teeth comprised fifteen girls (mean age: 10.3years) exhibiting the unerupted maxillary incisor. The group with crowded teeth consisted of fifteen girls (mean age: 10.2 years) with class I crowded malocclusion. All of the subjects were evaluated cephalometrically.
The results were obtained as follows.
1) L1 to Mp angle, Overjet and Overbite were significantly smaller in the group with unerupted teeth compared with the group with crowded teeth.
2) The values of ANS-U1e/ANS-Me and ANS-U1e/Me-L1e ratios were shown to be significantly smaller in the group with unerupted teeth than in the group with crowded teeth.
3) The distances between points A and Pr, and between points ANS and Pr were revealed to be significantly smaller in the group with unerupted teeth in comparison with the group with crowded teeth.
The above-mentioned results suggested that the unerupted maxillary incisors were associated with lingual inclination of the lower incisors, smaller height of maxillary alveolar process, and decreased overjet and overbite. These dentofacial anomalies with the unerupted maxillary incisors should be considered with respect to diagnosis, treatment planning and mechanotherapy.

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The present experimental study was a trial in order to test the hypothesis that Japanese eating habit has been changing as time passes. As the typical food for testing around the 1950's,1970's and the present era respectively, we selected three menus from two former and one current school lunch, which were normally eaten by numerous school children. The content of the lunches had been properly recorded and were able to be reproduced. Six subjects agreed to take part in the present experiment, and the total amount of mastication and the time for eating for each subject to eat each test food thoroughly were calculated through recorded videotapes.
The mean values from all of the subjects were compared to each other on the amount of mastication and the time required for eating the three kinds of the test food. The amount of mastication decreased with a shortened time for eating when eating the current lunch, compared to when eating the other two former lunches, In the replacement experiment, however, when Japanese rice mixed with the wheat of the current lunch was replaced by the French roll for the lunch of the 1950's with the same side dishes and milk, the amount of mastication increased with a longed time for eating, compared to the original current lunch.
The results from the replacement experiment indicated that the difference between the ages was not necessarily due to the change in Japanese eating habits as time passed. If the side menus are replaced and the method of cooking is changed, other results may be obtained. It appears to be quite difficult to determine the typical food eaten usually by Japanese at each time, based on just a few menus.

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To solve the drawback of poor esthetics with readymade metal crowns applied to primary molars, the author made, on an experimental basis, a new crown for which the color was a natural color similar to nylon 11, a polyamide resin made of polymer, developed rapidly in recent years for the surface on titanium readymade crowns. In this study, the experimental readymade metal crown for primary molars esthetics into consideration was coated with using nylon the fluidized bed coating method after blast treatment and was examined evaluate tensile shearing, friction, surface roughness water absorption and stain tests to investigate the clinical test. The results obtained were as follows.
1. The tensile shearing strength was shown to be 17 MPa as the maximum value and shown to be 10MPa after 5000 thermal cycles, which indicated it could be easily used for clinical application. Also, delaminating was not seen using the bend examination, and the utility of the blast surface treatment was suggested for the gluing of titanium and nylon.
2. The degree of stain on the nylon coating was similar to that of the self-cured resin, and the disappearance of the stain after brushing was easily compared with the resin, which seemed to maintain the oral esthetics.
3. Since the operation of cutting, countering and polishing of the new metal crown coated with nylon for primary molars were as easy as those for ready made metal crowns on the market, the author has succeeded in the development of a ready made metal crown for primary teeth taking esthetics into consideration.
4. It is clear that the developed esthetic crown with a nylon coat is available for clinical use without impairing the advantages of readymade metal crowns for primary molars

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The Purpose of this study was to investigate the stability of the masticatory rhythm among jellies composed of three different textures youngsters subjects. A total of 5 healthy subjects (2 male and 3female) with a mean age of 4.8 years were selected on the basis that they agreed to participate in the study and did not exhibit signs or symptoms of TMD. A jaw function tracking system (Gnatho Hexagraph, GC, Tokyo, Japan) tracked the movement of the edge of lower central incisor.5 adult volunteers with a mean age of 22.4 years also participated in the study for comparison of the characteristics of the jaw movements between the youngsters and adults. Jellies with three different textures for the test contained 3%,5% and 7% gelatin, respectively, and were standardized at the size of a 13 mm cube with a weight of 3.5 g. We assessed the opening time, closing time, occluding time and cycle time of the 10 strokes of the movement beginning with the fifth stroke of the mastication as the mastication rhythm parameter. The results indicated that the closing time was significantly dependent on the food texture (p<0.05) in youngsters, whereas the cycle time was constant in both youngsters and adults patients. We concluded that masticatory rhythm in youngsters was more unstable than in adults, because the phase was directly affected by the food texture.

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The purpose of the present study was to investigate skeletal and dental deviations in skeletal anterior openbites, and to establish treatment objectives for anterior openbites at the stage of the mixed dentition.
The study was conducted using the 40 forty-five degrees oblique cephalograms of 20 females with skeletal anterior openbite at Hellman's dental age IVA (the openbite group). The mean age of the openbite group was 18 years and 1 month ± 5 years and 3 months.
The 3 angular measurements for the skeletal deviations, and the 27 angular and 20 linear measurements for the dental deviations were calculated in the openbite group.The analyses of these deviations were made statistically compared with the norms reported in the study by Kamegai.
The characteristic features in skeletal anterior openbites were the obtuse gonial angle, the steep mandibular plane, the tipped up palatal plane, the mesial inclination and supraversion of maxillary first molars and buccal segments, the mesial inclination and infraversion of mandibular buccal segments, the distal inclination of maxillary and mandibular second molars. The interception of these morphological deviations was the objectives of the treatment for anterior openbites at the stage of the mixed dentition.

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The purpose of the present study was to investigate the coordination pattern of the laryngeal movements and the orofacial muscle activities when swallowing and to investigate the differences of the swallowing pattern between children and adults, and among different food textures.
The laryngeal movements and orofacial activities from the beginning of chewing to swallowing were recorded using the videofluorography and electromyograms from the temporalis and masseter muscles. In the first study, bread in which barium was added as solid food and Baritogen(Ra)s liquid food were used as the test foods in adults (6 subjects, mean age 29.3 yrs). In the second study, the difference in the swallowing pattern was investigated when ingesting three kinds foods with different texture (boiled fish paste, cooked rice, gummi jelly) in five children (mean age 6.9 yrs) and five adults (mean age 28.7 yrs).
The following results were obtained:
1. The temporalis and masseter muscles were activated before the onset of the sudden laryngeal elevation when swallowing, whereas the onset of the digastric and mylohyoid muscles activities nearly coincided with the laryngeal elevation.
2. Two types of swallowing pattern, the one-step motion and the two-step motion, were observed during swallowing of the solid food. As to the one-step motion, the swallowing started immediately after the bolus was transported into the middle laryngeal. On the other hand, the two-step motion of the swallowing started with some time-lags after the bolus was once transported into the middle laryngeal.
3. As to the influence of both the amounts of food and the texture of food on the swallowing pattern, there were no differences among amounts of food, texture, and between subject groups in the coordination of each muscle and the laryngeal elevation. There was a tendency however that the onset of muscle activity of adults was earlier than that of children.
In conclusion, it was suggested that no differences due to both the amounts of food and food texture were found in the coordination pattern of the laryngeal movements and orofacial muscle activities at swallowing, but there were some differences between children and adults in the swallowing pattern.

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Supernumerary teeth, a developmental anomaly, are often encountered in the clinic of pediatric dentistry. We therefore investigated children who visited our department of pediatric dentistry, Chiba Hospital, Tokyo Dental College and showed supernumerary teeth at the first examination.
Between January 1992 and December 2001,8,518 new patients visited our department of pediatric dentistry. Of these children,93 who revealed supernumerary teeth (125 teeth) at the first examination were entered into this study. The investigation items were: the history until the first examination, gender, age at the first examination, the number of supernumerary teeth, their locations, eruption state, the direction of the crown in impacted teeth, X-ray findings, and the dentition/occlusion state and management methods.
Of the 93 children,69 (74.2%) were males and 24 (25.8%) were females. The age at the first examination was most frequently 7 years. Supernumerary teeth were located in the maxillary incisor area in 92 children (98.9%) and in the mandibular incior area in the other. Of the 125 supernumerary teeth,48 (38.4%) had been erupted, and 77 (61.6%) were impacted. At the first examination, there were dentition/occlusion abnormalities that were considered to be to supernumerary teeth in 48 children (51.6%).
We will continue follow-up investigation of cases of supernumerary teeth and more detailed evaluation of their status for the appropriate decision of treatment principles.

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Although lateral expansion of the mandibular dental arch is not a general treatment in clinical pediatric dentistry and orthodontics, we have performed such expansion using active plate appliances. In this study, the influence of active plate appliances and wire-spring appliances on tooth movement and on periodontal tissue was investigated. Buccal movement (expansion) of the mandibular first molar area in rats was performed applying the force of approximately 10 g for 1,3,5,7, and 14 days, using active plate appliance models (Ap group), or wire-spring appliance models (Wi group). The distance of the tooth movement in the central fossa area of the bilateral first molars was measured, and significant differences in the distance in the experimental period were evaluated. Furthermore, changes in the buccal periodontal tissue were observed with an optical microscope using various staining methods, and observed with confocal laser microscope using time descriptive methods.
The amount of tooth movement showed no significant differences between Ap and Wi groups. The pattern of tooth movement showed 5 phases in Ap group, and 3 phases in Wi group. Although degeneration of the tissue on the compressed side accompanying tooth movement was noted until the seventh day both in Ap and Wi groups, it disappeared on the 14th day in Ap group. Remodeling of the buccal alveolar bone was observed in the area ranging from the alveolar crest to the basal side on the periosteal surface of the alveolar bone in Ap group, whereas bone induction was found only in the alveolar crest in Wi group. These findings suggested that lateral expansion of the mandibular dental arch is possible by using active plate appliances in clinical pediatric dentistry and orthodontics.

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Resin-modified glass ionomer sealant (Fuji III LC®)w as applied to immature permanent first molars in children who had been under regular dental care since the dental stage of primary dentition at the Clinic of Pediatric Dentistry, Division of Oral Rehabilitation, Hokkaido University Dental Hospital. It was demonstrated that the caries-preventive effects of Fuji III LC® were high. The clinical examination showed the cariostatic rate of 99.0% 1 year and 95.2% 3 years after application. Some caries incidence occurred, however, in surfaces besides the occlusal surfaces that were covered with the sealant material. This finding indicated the need of both additional application to unerupted fissures and other preventive procedures for mesial surfaces to prevent new caries production in immature permanent first molars.

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The aim of the present study was to discover acoustical features in the crying of children at the stage of language acquisition. As samples of the present study, sounds of crying of 2 and 3 year old children during dental visiting were recorded. We performed Fourier-transformation and made soundspectrograms from the wave files of the sounds of crying.
Firstly,6 volunteer evaluators, who were students of dentistry, evaluated the loudness and bitterness of the sounds of crying based on their subjective auditory-impression without fundamental knowledge of acoustics. From the results, we tried to select typical waveforms of sounds of crying, and then we discriminated two type of waveforms from the difference of those noise densities on the sound spectrograms. They were named N type and C type waveforms of crying, former one had high density of noise between formants and later one had low density and the layer structure, that was clearer than those of the N type of crying.
Secondly, we arranged 8 files (F1 to F8) of cry sounds which were comprised of two waveforms of cries. Four of the files ( F1 to F4) were combinations of loud or low crying of the N or C type of crying, which were selected by the evaluators. The others were combination of the N or C type of crying, of which the frequency or sound pressure were modified digitally. Thirteen pediatric dentists listened to the sounds in the 8 files and evaluated their auditory impression to clarify the relationship between the waveforms of crying and the auditory impression.
To compare the sounds of crying in F1 (Loud N: Loud C), F2 (Low N: Low C), F3 (Loud N: Low N) and F4 (Loud C: Low C),100%,100%,78% and 85% of the listeners felt that the former one of the two sounds of crying was more angry undesirable than the later one, respectively. They felt, however, the loudness of those sounds of crying were same in F1 and F3. Contrary to this, in F 2 and F4,94% of them felt the former sounds of crying were louder.
The results indicated that the N type of crying caused a stronger of lament to the listener than the C type of crying. Interestingly, the results from the other files (F5 to F8) of modified sounds of crying suggested that the impression of the N type of crying was almost independent from the frequency or sound pressure of these sounds of crying.

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To determine the effects of acidulated phosphate fluoride (APF) on the color tone of light-cured restorative materials, these materials were immersed in APF solution and color before and after immersion compared using a spectroscopic color difference meter.
The following 5 types of light-cured restorative materials (LRMs) were used: Fuji II LC Improved® (II LC; GC), Vitremer®(VT; 3 M), F 2000® Compomer (F 2000; 3 M), Clearfil® AP-X (AP-X; Kuraray), and Z 100® (Z 100; 3 M). The APF solution was, Floden® A (Sunstar) and 2nd APF solution produced in-house. To determine the effects of each component of APF,2% NaF and 1.73% phosphoric acid were also used. Distilled water was used as the control. Samples were immersed in the solution for 4 minutes at a time, with immersion repeated 4 times. The color tone was determined using a spectroscopic color difference meter SE-2000 (Nihon Denshoku Kogyo) before the first immersion and after each immersion. The color difference (E*ab) was calculated L*a*b* obtained before the first immersion and after each immersion. Statistical analysis was based on Student's t test and ANOVA and Tukey's HSD test. Significance was defined as 5%. The surface of samples after immersion was examined by scanning electron microscopy (SEM). As a result of immersion of Light-cured restorative materials in the APF solution for 4 mins, significantly more marked color differences were observed in LRMs other than Z 100 when compared to the distilled water group (p<0.05). The largest color difference was observed in AP-X (1.51), followed by VT (1.17), LC (1.12), F 2000 (0.48), and Z 100 (0.39). Values observed with F 2000 and Z 100 were significantly lower than those for the other 3 materials. After immersion of LRMs in APF solution, the color difference increased with the number immersions. After the fourth immersion, II LC showed the largest color difference (4.07), followed by AP-X (3.23), VT (2.81), Z 100 (2.32), and F 2000 (0.94), showing statistically significant differences among restorative materials. In changes in L*a*b*, L* increased and b* decreased after immersion of all samples, but no changes were observed in a*. After immersion of LRMs in 2% NaF and 1.73% phosphoric acid solution, no statistically significant differences were observed in color compared to distilled water samples. When samples after immersion were examined with SEM, erosion was observed in all samples after immersion in APF, indicating an association with the color difference. These findings suggest that APF solution application changes the surface of LRMs, there by affecting their color.

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Glass-ionomer cement is known to possess many advantages such as fluoride release and uptake for caries resistance, low degree of stimulation of the pulp, good clinical adhesion and high esthetic value. We have been investigating the possibility of improving the mechanical properties of glassionomer cement by adding short glass fibers to the cement. This study was carried out to evaluate the biocompatibility of glass-ionomer cement to which short glass fibers had been added. The viability of cells exposed to various specimens was investigated with MTT assays using rat pulp cells. The effect of fluoride release from the specimens was also investigated.
The following results were obtained.
1. The viability of cells exposed to the specimens was greatest in the case of Fuji II LC (G-C Co. Ltd. ) and Scotchbond Multi-Purpose (3 M Dental Products) followed by glass-ionomer cement (HYBOND GLASIONOMER CX; Shofu Inc. ) and glass-ionomer cement containing 20% glass fibers.
2. The pH values of those specimens immersed in culture medium changed to more neutral values due to the effect of the buffer. The pH of a specimen mixed only with glass fibers and polymeric carbolic acid solution was low.
3. Sufficient amounts of fuoride were released from glass-ionomer cement specimens immersed in culture medium. The addition of glass fibers did not reduce the amount of fluoride released.
The results showed that glass-ionomer cement containing short glass fibers has good biocompatibility and releases a sufficient amount of fluoride suggesting that this glass-ionomer cement is promising as new cement that has an anti-caries effect and has good mechanical properties.

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We carried out an investigation based on a questionnaire concerning the actual status of mouth breathing in nursery school children. The questionnaire was composed of 53 questions regarding oral breathing. The questionnaire cards were distributed among parents of children aged 4 to 6 years, and 206 cards were collected (74.9% recovery). The results are summarized as follows.
1)46 children (22.8%) of all of the subjects had a habit of keeping their mouth open both in the daytime and while sleeping, and 89 children (44.2%) always closed their mouth all day. We considered that the former was mouth breathing children and the later was nose breathing children.
2)Mouth breathing children demonstrated many significant differences from nose breathing children: greater prevalence of nose pharynx disease, catching a cold, lip and mouth drying, relaxation of lips and turned upper lip, errors in hearing, anterior malocclusion, unskillful chewing and swallowing, and stooping.
3)There were no significant differences in the prevalence of pacifier use and weaning time between mouth breathing children and nose breathing children.

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In connection with the growth of children who show various changes in physiological and psychological responses, there are reports that there has been a decline in physical functions, was a decline especially in mastication and the equilibrium functions. The purpose of this study was to consider how occlusion ability is related to the motion of the center of gravity. The subjects in this study were 163 nursery school children. This study involved the measurement of the physical and mental development states including the body measurements, oral states with the decayed and filled teeth, occlusion abilities with the Dental Prescale® and the motion of the center of gravity by the foot pressure gravity was measured. Moreover, questionnaires were used. Each measurement was compared and investigated.
The following results were obtained:
1. Concerning the occlusion abilities, the male groups showed a significantly wider occlusal contact area and a stronger occlusal force than the female groups. There was a significant difference between the chronological age and the occlusion abilities. A significantly positive correlation was found between the chronological age and the oral states as well as, in the occlusion abilities. A significantly positive correlation was found between the body height and the occlusion abilities.
2. Concerning the motion of the center of gravity, the female groups showed a significantly lower motion for all of the distances, all areas and amplitudes than the male groups. The motion of the center of gravity decreased significantly as the children grew. The foot pressure area significantly increased as the children grew. There was a significant difference between the dental age and the motion of the center of gravity and the foot pressure area. A significantly negative correlation was found between the physical and mental development states and the motion of the center of gravity. A significantly positive correlation was found between the physical and mental development states and the foot pressure area.
3. A significantly negative correlation was among between filled teeth, dental caries experience teeth and the motion of the center of gravity. There was a significant difference between the filled teeth existence of filled teeth and the motion of the center of gravity. A significantly positive correlation was found between the maximum occlusal pressure and the motion of the center of gravity. A significantly positive correlation was found between the mean occlusal pressure and the foot pressure area.
4. There was a significant relationship between the oral states, the occlusion abilities, the motion of the center of gravity and replies of the basic motor function, the micro motor function, the sense of equilibrium, the activities and the food habits.
It was concluded accordingly that the physical and mental development states, as well as the occlusion abilities and the motion of the center of gravity were closely related.

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For functional lateral cross-bite, the possibility of natural recovery is low, the possibility that moves to framework nature said that it is high when it leaves it.
The purpose of this research concerns the significance of placeable, early treatment for lateral cross-bite.
I compared and examined the author etc. after treatment and also the change of the maxillofacial structure in convalescence from before treatment of treatment opening time, by using frontal cephalometric radiography of case of lateral cross-bite that differs.
1. The right and left unsymmetry of maxillofacial reduced after during treatment and also the one that started treatment from II A and II C's Hellman convalescence observation. However, there was the analysis item that the right and left unsymmetry turned up once again during convalescence observation.
2. Is observed the reduction of the right and left unsymmetry was not observed after during treatment from before treatment and, the right and left unsymmetry of maxillofacial the one that started treatment from III A and III B's Hellman and also convalescence observation.

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The present study investigated 15 children with unilateral cleft lip and palate (UCLP) before orthodontic treatment (mean age of 4 years 1 month) and 13 control children (mean age of 4 years 4months) with normal occlusion of the deciduous dentition. Occlusal force, occlusal contact area, and mean and maximum pressure were measured using the “Dental Prescale®”, while dental arch forms were examined using plaster models.
The following results were obtained:
1. The occlusal force and occlusal contact area of children with UCLP were lower than those of the control children. Conversely, mean and maximum pressure displayed no significant differences.
2. The occlusal force asymmetry index and occlusal contact area asymmetry index of children with UCLP displayed higher values than those of the control children, while an imbalance was observed in the occlusal contact state between the right and left sides of the dental arch.
3. The occlusal force and occlusal contact area of the cleft side of UCLP children were compared with the non-cleft side, and values on the cleft side were found to be lower.
4. The Occlusal force and occlusal contact area tooth on the cleft side were compared with those on the non-cleft side. Excluding the deciduous central incisor, the non-cleft side displayed larger values, and tendencies similar to those for occlusal force and contact area distribution were observed.
5. The ratio of the maxillary/mandibular area of UCLP children was lower, but no relationship was observed between the values of the occlusal force, occlusal contact area and ratio of the maxillary/mandibular area.

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Changes in social environment have caused various changes in problems supporting juvenile among which child abuse can be noted. Child abuse can be classified into physical abuse, sexual abuse, neglect, and psychological abuse.
The health centers of different cities and localities have been grappling with these kinds of abuse through mother-and-child health work mostly in the medical field. In dental field, the cases of parents who do not take their children to dentists for treatment can be considered as a foam of neglect. In order to clarify this situation, dental examination was carried out twice on 237 children between one to six years of age, cared for at day-care centers, to discover the status of neglect of caries, bad habits and other dental problems.
Results were as follow;
1. The results suggested th at the parent-child relationship affects the oral condition in children.
2. Children not yet neglected but may be in the near future were also identified.
There is no uniformity in recognizing abuse and it is difficult to have a com mon concept or standard in understanding abuse.
Particularly when ne glect is concerned, there is no direct evidence and it is often discovered indi rectly. Evaluation by a third party as to whether dental treatment is properly done, existence of serious caries, and the state of the parent-child relationship as well as recognition and evaluation of and attention to the condition of children at day-care centers were considered effective in supporting the bringing up children and consequently in preventing neglect.

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We have recently reported that the EL (epilepsy-like disorder) mice have a high incidence of missing third molars and fused roots of the upper first molar. The purpose of this study was to determine whether the appearance of the fused upper molar roots is controlled by genetic factors. The genetic study was performed on genetic crosses of EL mice, which had fused roots, and DDY mice, which had normal roots. The frequency of the fused roots was 60% for the EL mice and there was no significant difference between the sexes. There were no observations of the fused roots in both DDY and F1 hybrids,9.1% of the F 2 mice had fused roots of the upper first molar. The incidence of the fused roots (mesio-buccal and lingual roots) with unilateral was 77.8% for the EL mice and was 100% for F2 mice.
Based on the results of the incidence rates of the fused roots in both F 1 hybrids and F 2 intercross mice, it was suggested that the genetic factor as autosomal recessive inheritance affected the development of the fused upper molar roots in EL mice.

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The purpose of this study was to detect genetic factors affecting the appearance of cleft palate induced cortisone using genetic crosses between A/WySn and C 3 H/He mice. Embryos From withinstrain breeding of A/WySn and C 3/He, and the F₁ intercross and N₂ backcross embryos from crosses between the two strains were used to evaluate cortisone susceptibility. On day 11 to 14 gestation, the mice were given subcutaneous injections of cortisone acetate. On day 18 the embryos were dissected for observation of cleft palate. The frequency of cleft palate in the A/WySn strain treated with cortisone was 65.4%, on the other hand 12.1% in the C 3 H/He mice. The frequency in F₁ mice was significantly lower compare with that in the A/WySn strain, indicating recessive transmission. To investigate the influence of an X-linked factor, we judged the sexuality of N₂ embryos using polymerase chain reaction (PCR). There was no significant difference in the incidence between the sexes among N₂ mice. These findings suggest the cortisone-induced cleft palate in mice was influenced by major gene effect with autosomal recessive transmission. Genetic maternal effect in the appearance of cleft palate was not detected in this study. The significant difference between the two strains in the incidence of cleft palate indicates that mapping of susceptibility loci for cortisone would be possible using linkage analysis. To evaluate a linkage between the gene responsible for cleft palate inducing cortisone and H-2 region on chromosome 17, which have been associated with cortisone susceptibility, we performed the genotyping of the individual N₂ with cleft palate using MIT primer located in the H-2 region. The genotyping results suggested that the H-2 S region might be associated with cortisone susceptibility in the occurrence of cleft palate.

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Extracellular matrixes are known to control cellular functions such as differentiation and proliferation. The epithelial rests of Malassez (ERM) are the only odontogenic epithelium which remain inside the periodontal membrane after completion of the dental roots. In the present study, the effects of four extracellular matrixes, fibronectin (FN), laminin (LN), osteopontin (OP) and collagen type I (Col I ), on adhesion and proliferation of ERM cells as well as on expression and tyrosine phosphorylation, focal adhesion kinase (FAK), paxillin and L1, were investigated. When ERM cells were incubated with each extracellular matrix, FN and Col I significantly facilitated adhesion, while LN and OP suppressed adhesion and proliferation. Although no marked changes were seen in the expression of FAK, paxillin and L1, changes in the level of tyrosine phosphorylation were seen. At 60 minutes after incubation, OP and Col I facilitated tyrosine phosphorylation of paxillin, and at 3,7 and 14 days after incubation, there were changes in tyrosine phosphorylation of FAK. In addition, at 14 days after incubation, tyrosine phosphorylation of L1 was confirmed. These findings suggest that extracellular matrixes influence adhesion and proliferation of ERM cells and tyrosine phosphorylation of the abovementioned proteins.

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It has been reported that dietary factors such taste and nutrients affect satiety and energy balance. We hypothesized that hardness of food might contribute to the regulation of energy metabolism through the process of mastication in the oral cavity as well. Effects of feeding with different textured pellets but with nutritional components and shape the same on feeding-behavior, postprandial thermogenesis and locomotor activity were assessed. The average hardness of the soft pellets requiring less chewing was half of the controls, respectively. Mature male rats were operated on to put the thermosensor in their peritoneal cavity for measurement of body temperature and locomotor activity. After the rats had fasted for 24-hrs, and given soft or control diets, their body temperature and activity were recorded under free moving at i-min intervals. Their feeding behavior was observed for an hour after starting the meal. All of the rats were fed both control and soft pellets.
The increase of body temperature following feeding (postprandial thermogenesis) was significantly lower when the rats were fed with the soft pellets than the control pellets, although feeding-behavior and locomotor activity were not different. These results suggested that food texture affected postprandial thermogenesis through the changing of oral sensations.

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The purpose of this study was to investigate the actual status of medically compromised pediatric patients who visited Arai Dental and Pedodontic Clinic in Sapporo, and to review the collaboration of their treatment with facilities providing advanced dental or medical care though 8 clinical cases.
A clinico-statistical survey was performed on 196 medically compromised pediatric outpa tients who underwent dental treatment in the clinic during the past ten years.
The results were as follows.
1) The age of the patients were distributed predominantly between 3 ∼ 5 years of age, representing 50.5% of the 196 cases. The ratio of the medically compromised patients among the total number of pediatric patients 15 years or under was 7.2%.
2) About 70% of the patients were referred by schools, other clinics or other institutions and 39.3%were referred by their acquaintances.
3) Among 196 cases,81.6% lived in the same ward of Arai Dental Clinic. However,61.3% visited the clinic from an area taking 15 minutes or longer on foot.
4) Respiratory disease, especially asthma were found to occur most frequent at all ages, and patients suffering from respiratory disease represented 37.7% of the 196 cases.
5) The majority of the patients older than 2 years visited the clinic for caries treatment. Most of the parents of the children 2 years or under wanted them to have preventive dental care.
6) General medication had been administered to 82.1% of the patients. However, sometimes the history was not indicated in the inquiry sheets and medication of 24.4% of the patients was not confirmed at the initial dental examination.
7) Based on the 8 cases that showed some abnormality in physical condition or behavior during dental examination or treatment, we recognized the importance of collaboration by a primary dental clinic with facilities providing advanced medical or dental care.

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No objective determination of standard values for the solidity of food for infants has been carried out. This study aimed at obtaining data on the appropriate consistency of food for infants. We examined the solidity from weaned subjects in four different stages The subjects were divided into four groups according to the development stage of feeding after the observation of the researcher of the movement of the oral region. Four different levels of solid foods were prepared and used for this study as a standard food. The four groups of the weaning infants were compared with respect to both the appropriateness of how to process food in feeding and the number of times of the movement of the lower jaw The following results were obtained:
1. As the hardness of the test food increased, the proportion of infants capable of eating it decreased
2. It was observed that when infants chew food, the solidity of that food determines the number of occlusal movements made by the lower jaw
3. It was suggested that the number of jaw movements used to cope with the solidity of the food varies with the stage of weaning Approximate standards of the solidity of food which infants at each stage can process have been established. Future investigation of the appropriate number of movements of the lower jaw is considered necessary for foods with these various solidities

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The biological effects of the Mandibular lateral expansion appliance were investigated. An orthodontic plate (Schwarz appliance) was mounted on dogs for 56 days. Basal metabolism such as body weight, behavior, appetite and feces, biochemical data on blood (15 items) and effects on the oral mucosa were compared between the test dogs and control dogs without the appliance. The following results were obtained:
1) The body weight of the test dogs was decreased slightly immediately after fixation of the appliance, but then quickly recovered. Little or no difference was observed between the test and control dogs. There was also no significant difference in behavior, appetite and feces between the two groups.
2) Based on the biochemical blood tests, It was found that the activity of alkaline phosphatase increased on the day after fixation of the appliance. The increase was within the normal range, however and the activity returned to a level similar to that before the mounting within approximately one week. The remaining 14 values of the blood tests also showed no significant difference compared to the results of the control dogs.
3) With the examination of the oral mucosa, mild inflammation was found in the buccal and lingual marginal gingiva, while no inflammatory images were observed in the lingual gingiva with which the appliance made contact.

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Previous studies showed the occluding area, which crushes the food in the dental arch, is fixed and it mainly involves the first molar in adults. This study was conducted to investigate the change of the occluding area according to dental stage of children. All of the subjects were divided into six groups according to Hellman's dental stage. The subjects were asked to clench freely a temporary stopping®as a test food placed on their tongues for five trials. The most frequent clenching area in each subject was defined as the main occluding area at mastication. The results were follows:
1. The main occluding areas in mastication from stage II A to stage IIIA were the primary molars. This changed from the primary molars to the first molars because of exfoliation of the second primary molars. After that, the area was that of the first molar. However, the occluding area in children was not so constant as in adults.
2. The main occluding area changed according to dental stage in children, which suggested the change of the main occluding at mastication according to dental stage could be used as an indicator of the development of the masticatory function.

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The object of this study was to considering the present status oral as the index for future for measuringral healthy improvement while it clarified the daily life styles of the children of Changchun-city. The questionnaires were used for 160(3∼5 years of age)kindergarteners,216(7∼12 years of age)school children and guardians who live in Changchum-city, Jilin, China. The results were as follows.
1. The rhythm of life, such as the time zone of breakfast and dinner and sleeping time, were regular.
2. Drinks and sweets were given freely whenever the child wanted them.
3. There were many children who complained about symptoms of disease in the oral cavity.
4. The knowledge and consciousness toward oral hygiene was differed from that of Japanese people.
It is conjected that understanding the influence of the dietary habits on the body and givin g actual oral hygiene education to both parents and children would be the key to improve the oral health.

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The RPMI-1640 semisolid medium method was used to study the effects of nicotine on BMP secretion of mouse molar tooth germs in vitro. The molar tooth germs were removed from 16-day old mouse embryos and cultured. In the experimental group, nicotine was added into the RPMI-1640 medium with the final concentration of 10 mg/ml. In the control group, the molar germs were cultured with RPMI-1640 without adding nicotine. After a 4-day culture, tooth germs were fixed and prepared for ABC immunohistochemical staining to detect the appearance of BMP in tooth germs. Weak positive staining of BMP was observed in the tooth germs of experimental group. However, strong staining of BMP was observed in the enamel organ and dental papilla of the control group (p<0.01). The present results suggest that nicotine may play an inhibitory role in MBP secretion of cultured mouse tooth germs.

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Abstract: The purpose of this study was to analyze the role of a university dental hospital in the community. Characteristics of patients who visited the Pediatric Dentistry Clinic of Hokkaido University Dental Hospital for the first time during a five-year period, from April 1996 to March 2001, were investigated. The following results were obtained:
1. There was an increase over the five-year period in the number of patients visiting our clinic for the first time.
2. The mean age of all patients who visited our clinic during the five-year period was 6 years and 8months, and the mean age of patients visiting our clinic in each year of the five-year period ranged from 6 years and 2 months to 7 years and 5 months.
3. About 77% of the patients visiting our clinic each year resided in Sapporo, where our clinic is located, and the other patients came from various parts of Hokkaido, the island on which Sapporo is located.
4. In each year of the survey period, about 40% of the patients visiting our clinic for the first time were patients who had been referred by dental clinics and about 15% were patients who had been referred by medical hospitals.
5. In each year of the survey period, about 25% of the patients visiting our clinic for the first time had some kind of systemic disease.
6. In each year of the survey period, the largest percentage of patients visiting our clinic for the first time were patients with dental caries as the chief complaints, although the percentage of such patients decreased during the five-year period. The second-largest percentage of patients visiting our clinic for the first time each year were patients with malocclusion or abnormal directions of the erupting teeth as the chief complaints, and the percentage of such patients increased during the five-year period.
The results of this study indicate that our clinic plays an important role as a facility off ering highlevel dental treatment and services not only in Sapporo but also for all of Hokkaido.

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Abstract: The purpose of this study was to analyze the role of a university dental hospital in the community. Characteristics of patients who visited the Pediatric Dentistry Clinic of Hokkaido University Dental Hospital for the first time and who made subsequent regular visits during a five-year period, from April 1996 to March 2001, were investigated. The following results were obtained:
1. The number of patients visiting regularly decreased from 15 to 20% every year.
2. There was a decrease in the percentage of patients aged from 6 to 12 years, and more than 13 years old at the time of the first visit who continued to make regular visits to our clinic after the first visit.
3. The percentage of patients living in Sapporo who made regular visits to our clinic was higher than the percentage of patients living in other parts of Hokkaido who made regular visits to our clinic, and some patients living in places distant from Sapporo did not make any further visits to our clinic after the completion of treatment in our clinic.
4. The percentage of patients with some kind of systemic disease who continued to make regular visits to our clinic was higher than the overall percentage of patients who continued to make regular visits.
5. More than 60% of the patients whose chief complaint at the first visit was dental caries or trauma continued to make regular visits to our clinic. The majority of patients with tooth abnormalities such as impaction of a supernumerary tooth or soft tissue abnormalities such as the frenulum abnormality visited the dental clinic by which they had been referred to our clinic for treatment rather than continue to visit our clinic after completion of the surgical treatment in our clinic.
The results of this study indicate that our clinic plays an important role as a facility offering highlevel dental treatment and services. However, the decrease in the percentage of patients who continue to make regular visits to our clinic after the first visit indicates the need for re-evaluation of the regular visit system used in our clinic.

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We report the case of a child of a Japanese father and Brazilian mother who visited our department to under go caries treatment. At the examination, a geminated tooth considered to be caused by the concrescence of the left mandibular central incisor and several supernumerary teeth was found. Geminated teeth are rare, and the following findings were obtained.
1. X-rays showed a geminated tooth caused by the concrescence of the left mandibular central incisor, one erupted supernumerary tooth, and two impacted supernumerary teeth, and the presence of the teeth adjacent to the geminated tooth in the area corresponding to that of the left mandibular central incisor was confirmed.
2. Although the concrescent tooth area between the left mandibular central incisor and the erupted supernumerary tooth was united by dentine-like tissue containing some enamel areas, the concrescent aspects of the impacted supernumerary teeth were not clarified.
3. The mesio-distal diameter of the geminated tooth in the area corresponding to that of the left mandibular central incisor was slightly smaller than that of the normal tooth in Japanese males.
4. Careful dental care was recommended.

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We encountered a case of a 12-year-old boy who suffered from temporomandibular disorders (TMD) caused by the residual lower second deciduous molars. His chief complaint was a jaw-opening disorder accompanied temporomandibular joint (TMJ) pain. There were residual lower second deciduous molars on both sides covered with a mental cap causing occlusal interference during the side shifts of the jaw. The signs and symptoms of the joint sounds were not identified during functional jaw movements on both sides.
The signs of the joint effusion, which were classified as extensive fluid, were found on five continuous sections on magnetic resonance (MR) imaging of the MTJ. He was diagnosed as having capsule-ligament disorders based on clinical and MR imaging findings. We suspected that the signs and symptoms of the TMJ were caused by occlusal interference depending on the residual lower second deciduous molars.
We therefore extracted the residual lower second deciduous molars on both sides under local anesthesia on the same day. After extraction of the teeth, sings and symptoms of TMD greatly improves, and He has not complained of any pain in the orofacial area and the signs of the joint effusion on MR imaging of the TMJ have disappeared then. We concluded that the occlusal interference depending on the residual second deciduous molar could be the cause of TMD.

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We often encounter trauma to the maxillofacial or oral region, soft tissue wound which occurs to a child when alone and which is frequent, incidency of treatment have increased. In the buccal fat pad, herniationt is common, and the toothbrush is often a cause of such wounds. A case is described in which trauma to the cheek resulted in herniation of the buccal pad of fat into the oral cavity. The patient was a boy two years old five months of age. He fell from the sofa while brushing his teeth, with a toothbrush and there was a wound lingua for the buccal mucous membrane. He was admitted hemonhage and pain, but after the arrest of hemorrhage, he calmed down obedient. When his mother examined him the next day, she observed a mass protruding through the right buccal mucosa in his oral cavity. Afterwards, the masticatory dysfunction occurred, and he came to the Tokyo Dental College Suidobashi Hospital Department of Pediatric Dentistry. Phyma was recognized continuously from the rupture in the vicinity of the right buccal mucous membrane parotid papilla in the whity-yellow color by the size of thumb-tip. With diagnosis of the buccal fat pad herniation due to vulnus, we applied suture linguas to excise the phyma under general anesthesia. The antimicrobial drug and antiinflammatory enzyme preparations were administered to the infection. Histologicaly, it was a diagnosed a panniculitis with infection. The prognosis about two years after the operation up to the present time is excellent. When giving toothbrushing instruction to the children, we should see the guardian is properly warned about various dangers.

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We encountered a boy with Coffin-Lowry syndrome which is an X-linked inherited disease. In the present study, we examined the situation by studying a cast model, using X-ray photographs including cephalometric analysis and the polymerase chain reaction (PCR) method for the detection of periodontal pathogens
1. The patient was considered as being atypical case of the Coffin-Lowry syndrome with mental retardation, asmall stature, low weight, pectus carinatum, thoracolumber kyphosis and hyperplastic terminals of each finger.
2. Lateral cephalometric analysis revealed that the patient showed less growth of the oral and maxillofacial region, and in particular, N-Ans was over 3 SD smaller than that of the control.
3. Dental X-ray examinations showed noticeable root resorption of the upper central incisors and horizontal alveolar bone resorption around the lower central incisors. Furthermore, PCR analysis revealed that several putativeperiodontal pathogens, such as P. gingivalis and A. actinomycetemcomitans harbored in the oral cavity of the patient.

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