Two siblings diagnosed as having dentinogenesis imperfecta were referred to the pedodontic clinic of Tsurumi University Dental Hospital for dental care. The mode of inheritance in these cases was indicated to be the autosomal dominant trait according to the maternal pedigree studies, although their parents and maternal siblings were not affected.
Their oral manifestations and the histological findings of the extracted primary teeth exhibited typical characteristics of dentinogenesis imperfecta. The teeth of both primary and permanent dentitions were opalescent and grey-bluish in color and worn significantly. They showed apparently different patterns of wear because of the different dental care rendered to them. Obliteration of the pulp chamber and root canals was observed by X-ray survey as well as by histological investigation.
The enamel was basically normal but seemed to chip off easily due to a fiat dentino-enamel junction and supporting mantle dentin anomalies. The roots of these teeth were short and tapered off toward the root apices.
Clinically, the teeth of the younger brother who has received periodical dental care ever since early age were noticeably saved from deterioration, while those of the elder sister whose dental care was rather delayed, were significantly damaged. Therefore, the importance of dental care starting at an early age was emphasized to prevent these affected teeth from deterioration.

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A roentogen cephalogram is one of many clinical examinations that are used in pedodontic practice but there are many problems involving danger with X-ray exposure, the limitation of the area to be photographed, ect.
We therefore studied whether we could substitute the tracing of a photograph taken with a modefied type of commercially cheaper facial standarized photography and made with a facial standarized photographic analyser for roentogen cephalograms. As a result, we obtained the following conclusions
1. We found out that the number of coincident landmarks on the soft tissue and the hard tissue of the lateral cephalogam with a 5 degree oblique cephlogram was the same statistcally in an X, Y coordinate system at Pn and Fh reference point.
2. Coincidence between the landmarks on the soft tissue of the left side 5 degree facial standarized photograph and lateral cephalogram was higher. We found that we were able to substitute the left side 5 degree oblique facial standarized photograph for the lateral cephalogram.
3. Therefore, we discovered that we encountered a higher possibility of being able to predict landmarks on the hard tissue from the left side 5 degree oblique facial standarized photograph.
4. Landmarks coincident to both the left side 5 degree oblique facial standarized photograph and on the lateral cephalogram were points of Fh, No, Pn, Ul, Ch and non coincident landmarks are points of Sbn, Ls, Ll, Sc.
5. We found out that the reliability of non coincident landmarks on the left side 5 degree oblique facial standarized photograph with on lateral cephogram was higher on the left side 5 degree oblique facial standarized photograph than on the lateral cephalogram.

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In this study, the factors influencing the adaptability of the child to the first visit to the dental clinic were analized.
The subjects were a total of 306 persons consisting of 102 children ranging from 3 to 12 years of age and 204 parents who had visited the dental clinic of the Department of Pedodontics, School of Dentistry, Aichi-Gakuin University.
A total of 32 items consisting of 16 items from the parent-upbringing test and 10 items from the child personality test and 6 items from the questionnaires recorded in the dental charts were defined.
Discriminant analysis was carried out according to the second class of Hayashi's quantifying theory concerning the adaptation or maladaptation chosen as an external criterion
The results are summarized as follows:
1. The ratio of the distinctive efficiency of external criteria to the adaptation or maladaptation was found to have a high correlative coefficient,0.66.
2. The factors influencing the adaptation group were found to be in the following areas.
1) Concerning the manner of upbringing, the father had strong tendency in the“positive dis-approval pattern”category.
2) Concerning the manner of upbringing, the mother had a weak tendency in the“anxiety pattern”category.
3) Concerning personality, the children had a“sociability pattern”,“maladaptation to the family pattern”and non“aggressive movement pattern”(rational pattern).
3. When the factors mentioned above are ranked according to the external criteria the order is as follows:“ sociability pattern”in the child,“maladaptation to the family pattern”in the child,“positive dis-approval pattern”in the father,“aggressive movement pattern”in the child,“low anxiety pattern”in the mother.

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Dental care for the residents in the mountain village where there are no dentists encountors many difficult problems. One of the plan for finding a solution to these problems involves the establishment of a dental health care system on independent principles in the village.
The present study aimed at exploring an actual and effective program for a dental health care system in a village having no dentists.
The data were obtained in Shirakawa village, Oono country, Gifu prefecture. The adult residents over thirty years old were examined with respect to their oral health status and dental care.
The Cultural background of the village was also investigated.
The results obtained were as follows:
1) The average number of teeth see subject was smaller, and the number of men who used full-dentures was greater when compared with the average in Japanese Adult. The condition of the periodontal tissue was bad.
2) A economic burden and the time that is needed for going to a dental office was extremly great.
3) Dental prevention-consciousness of the residents was low judged from their oral hygiene habits and number of visits to a dental office.
4) It was suggested that the introduction of dental health examinations and guidance for newborn infants and the family must be enforced for improvement of the oral health status of the residents living in Shirakawa Judging from the results the research which was done over 2 periods.

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Dental care for the children living in the mountain village where there are no dentists encounters meny difficult problems. Although administering dental care is difficult, one of the major problems is an insufficiency with respect to the dental needs. Temporarily organized therapeutic teams have principally supplied emergency treatment, but such emergency measures have not effectively improved the oral health status of children in the Mountain Village, because theraupeutic measures can not reduce the amount of the need for dental treatment, and therefore can not bring about an introduction of the preventive guidance most required for dental health care.
The present study aimed at estimating the result of simple and easy instructions for dental health care given to children living a mountain village having no dentists, according to the principle“prevention is better than cure”.
The data were obtained from the children in Shirakawa Village Oono country, Gifu Prefecture.
The children were examined with respect to their oral health status and dental home care.
The results obtained were as follows:
1) A greater decrease in the prevalerce of carious teeth was generally observed after the instruction as opposed to before. The tendencies towards Decrease were apparent with respect to the different tooth segments, and the decrease concerning the maxillary deciduous central incisor and mandibulary concering the maxillary deciduous central incisor and mandibulary deciduous nmolar was particularly noteworthy.
2) The rate of treated teeth and treatment status were improved.
3) The Oral hygiene habits of children have not changed due to the instruction, but the intake times of between-meal snacks were improved.
4) The Dental prevention-consciousness of the mothers and adults who are bring up the children were improved as results of the instruction.

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Histochemical localization of γ-glutamyl transpeptidase (γ-GTP), and measurement of γ-GTP activity, alkaline phosphatase activity, protein, calcium and phosphorus were investigated in the tooth germ of new born rats, aged 2,6,10,14,18, and 21 days old. Developmental changes fo γ-GTP activity and its localization were observed during the early mineralization of the moalr tooth germ. The peaks of γ-GTP activity and protein were observed in 7 and 17 days old rats, but the calcium level was inversed at the same time periods. The levels of phosphorus and alkaline phosphatase activity showed periodic changes in a 3 day segment during the developmental stage.

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For obtaining the better retention of a sealant, the necessity of the acid etching of surface enamel is well recognized. However, conventional acid etching would not produce homogeneous and sufficiently etched enamel. A recent study of our collegues has suggested that ultrasonic treatment in addition to the conventional acid etched technique could produce better etched enamel. Etching with phosphoric acid is considered to be no problem clinically and the etched surface, left unsealed, may return to a normal appearance. Horowitz and his collegues suggested that an acid etched, unsealed surface or even a surface from which the sealant has been lost are not more susceptible to decay than uneched surfaces. In the present study, fluoride effects on unsealed acid etched enamel are critically evaluated on an in vitro basis.
Freshly extracted premolars were used and the labial enamel surfaces were given the following treatment and grouped as follows,
A: Conventional acid etching for 60 seconds
B: Ultrasonic acid etching using ultrasonic tip (GOOF, Odontoson,41KHz)
C: Ultrasonic acid etching using ultrasonic cleaner (YOSHIDA, Ultosonic III,42KHz)and then immersed in sodium fluoride solution at different concentrations (9000ppmF^-,500 ppmF^-,10ppmF^-, pH 6.5∼6.8) for different periods of time (3 min.,24 hrs.,1,3,5,7 weeks). Surface changes of the enalmel were then examined with the aid of a scanning electron microscope ( JEOL, JSM-35C), electron probe X-ray microanalyzer (SHIMADZU, EMX-SM), microradiography (NIPPON SOFTEX, Softex-CMR) and changes of crystallinity were exam ined with X-ray diffraction (RIGAKU, Microflex and Microforcus Laue Camera). Also variation of crystallinity was estimated from the half-line breadth value (310), (002) reflections of enamel apatite. The reaction products were also identified with the A. S. T. M. cards.
The result obtained in the present study were as follows:
1) An ultrasonic acid etched enamel surface showed that enamel rods appear clearly throughout, and more etching occured at the periphery of rods.
2) The crystallinity at the etched enamel surface was decreased both in the a-axis and the c-axis.
3) Calcium fluoride was identified on enamel surfaces after being immersed in the 9000 ppmF^- and 500 ppmF^- fluoride solution for 7 weeks.
4) The intensity of FKand CaKevaluated with an electron probe X-ray microanalyzer was highest in the superficial layer after being immersed in the 9000ppmF^- and 500 ppmF^- fluoride solutions, and PKα decreased in the superficial layer.
5) The crystallinity of the acid etched enamel apatite was increased both in the a-axis and the c-axis directions when the specimen was immersed in the 500ppmF^- and 10 ppmF^- solution for 7 weeks.
These results suggested that a low concentration of fluoride solution will be effective for remineralization on acid etched enamel.

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The relationship between phenytoin (DPH) levels in blood plasma or saliva and gingival hyperplasia were investigated in 36 epileptic severely handicapped patients who had been administrated with DPH for a long period of time in an asylum.
The DPH concentration of plasma (total), ultrafiltrated plasma (free), whole saliva or parotid saliva were determined with homogenous enzyme immunoassay. The grade of gingival hyperplasia were evaluated following Isikawa's criteria.
The results were as follows:
1) DPH concentration in parotid or whole saliva correlated to the free DPH of plasma. The concentrations in the saliva approximated the free DPH of plasma.
2) The ratios of each DPH concentration to the total plasma DPH were almost the same: 15.3% for free DPH,19.0% for parotid DPH,14.3% for whole saliva DPH.
3) These data suggest that the determination of concentration of DPH in whole saliva is a more beneficial method to monitor the effective concentration of protein unbound plasma DPH.
4) Through oral examination,32 out of 36 patients were found to be suffering from gingival hyperplasia: 14 mild,11 moderate and 7 severe cases respectively.
5) The comparison of DPH concentrations among the groups with severe gingival hyperplasia showed a significant difference between the mild and the severe cases in total plasma (p<0.001), in whole saliva (p<0.001), and in protein unbound plasma (p<0.001); between the mild and the moderate cases in total plasma (p <0.001), and in protein unbound plasma (p<0.05); between the moderate and the severe cases in whole saliva (p<0.02). Significant differences were also observed in the volume of DPH secretion per hour between the mild and the severe cases in whole saliva, between the mild and the moderate cases in parotid saliva.
6) A significant correlation was observed between the grades of gingival hyperplasia (grades 1 to 18) and DPH concentrations of total plasma (r_xy=0.71, p<0.001), whole saliva (r_xy=0.69, p <0.001), protein unbound plasma (r_xy=0.57, p <0.01), parotid saliva (r_xy=0.55, p <0.02); correlations were also observed between the grades of hyperplasia and the volume of secretion per hour of DPH of whole saliva (r_xy=0.42, p <0.05) and parotid saliva (r_xy=0.52, p <0.05).
7) These data positively suggest a relationship between the DPH concentration and gingival hyperplasia. However, totaly neglected oral dental hygiene found in severely hadicapped patients was considered to be related to aggravated gingival hyperplasia.

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Blood plasma and saliva were analyzed from severely handicapped patients (36 cases) with the administration of Phenytoin (DPH) in an asylum.
One potion of blood plasma was ultrafiltrated with ‘Ultrafree’(Worthington)(free DPH). Saliva was taken from the oral cavity (whole saliva) or from the parotid duct (parotid saliva) with a plastic tube and then the changes of salivaly composition after DPH administration were investigated.
The results were as follows:
1) Both the total and free DPH concentration of blood plasma correlate to the DPH concentration of whole and parotid saliva.
2) Increases of whole salivary calcium and inorganic phosphorus were noticed in the DPH administered group.
3) Both concentration and secretion of salivary calcium and inorganic phosphorus were significantly correlated to the total DPH, free DPH and whole saliva DPH concentration.
4) No correlation between the calcium and inorganic phosphorus and the concentration of DPH was noticed in parotid saliva.
5) These results suggest that the change of concentration of salivary calcium and inorganic phosphorus are reflected by the plasma DPH.

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It is now widely known that the silent period (SP) would appear on the EMG of masticatory muscles in adults. However very few studies have been made with children especially during the state of deciduous dentition. The present study was so designed to investigate the phase of SP and latency (La) in children and to compare this with that of adults and to attempt the possibility of any clinical application of SP on the functional diagnosis of occlusion in children.
Fifteen children and eleven adults were subjected to the test and the electromyographic activities in the anterior temporal and masseter muscles during tooth tapping were recorded bilaterally and occlusalsounds recorded from the forehead of the subjects were monitored. The metal overlay was placed on the mandibular right deciduous second molar of five children out of 15 to cause an intentional occlusal interference and its effect on EMG changesparticularly on the duration of SP was critically evaluated.
The results obtained in the present study were as follows:
1. Occurence of SP during tooth tapping wassignificantly lower among the children (92.7%) than among the adults (100%).
2. There were no significant differences in La between children and adults. Making a comparison of muscles ipsilaterally, La oftemporal muscles was significantly longer than that of the masseteramong the children, but no differences were noticed among the adults.
3. The duration of SP was significantly longer inchildren than in adults. Making a comparison of muscles ipsilaterally, SP ofmasseter muscles was significantly longer than that of the temporalis in both groups.
4. There was little influence on the duration of Laafter intentional occlusal interference.
5. The duration of SP increased significantly from immediately after placement of overlay to its removal, but showed a declining tendency with respect to its initial value with elapsed time. In comparison of interfered and non-interfered sides, no differences in the duration of either La and SP were found.
These results suggest that it is possible to apply the duration of SP clinically to the functional diagnosis of occlusion in children.

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Glass ionomer cement developed by Wilson et al.1971 is a very similar material to silicate cement. It consists of ion leachable alminosilicate glass and fluoride is contained as flux.
The present study was carried out to examine the inhibitory effect of glass ionomer cement on recurrent caries. Prior to the experiment, microleakage of the cement, the amount of fluoride released from setting cement, and alteration of pH of the cement were measured, and then the influence of the cement on the enamel cavity wall was compared to that of silicate cement and composite resin in vitro. The influence of the dentinal cavity wall was also examined in vivo.
The results obtained from the present studies were as follows. In the enamel cavity wall, the improvement of acid resistance and crystallinity in the a-axis of the enamel apatite were noticed, and this was considered to be improved due to fluoride uptake into the tooth structure from the glass ionomer cement. However, in the inner enamel cavity wall, slight subsurface demineralization was noticed, and a slight decrease of crystallinity in the c-axis of the enamel apatite was noticed. This may be considered to caused by the residual acid of this cement.
In the dentinal cavity wall, fluoride uptake up to approximately 100μm depth was detected, and hypermineralized peritubular dentin with a gradually increased width in the surface layer of dentinal cavity wall was observed.
Based on those results, it was suggested that glass ionomer cement has an inhibitory effect on caries recurring at the cavity margin.

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This study was attempted to investigate the effect of acid etchants on normal and carious primary dentin.
Extracted or exfoliated teeth (noncarious: 26 cases, caries extended into the dentin: 8 cases) were used. The morphology of the prepared cavity surfaces, softened dentin removed surfaces and the etched dentin surfaces were observed through a scanning electron microscope. Cavities were prepared dry with the diamond bars, softened dentin was removed with the steel bars and a hand instrument. The dentin was then etched for 1 minute with acid etchants. The following observations were obtained.
1. In the cases of cavities cleaned by water spray alone, the dentinal surfaces were completely covered with a thick smear layer and anatomical details such as tubles could not be seen.
2. In the cases with normal dentin etched after cavity preparation, the dentinal tubles were opened, but the smear layer remained on some parts of the etched dentin. In some cases, small fibers were exposed in the opened dentinal tubles.
3. In the cases with caries decayed dentin, etched after removal of the carious lesion, the dentinal tubles were opened, but the effect of the acid etchants was less than in the normal cases. In many cases, some parts of the intertublar dentin and dentinal tubles were covered with a smear layer. In some cases, most tubles were filled with tubelike, cylindrical, crystallike and amorphous materials even after etching.

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The relationship between the eruption of succedaneous teeth, such as mandibular lateral teeth, and the factors contributing to their eruption was investigated statistically.
The materials were the serial 45° oblique cephalograms obtained from 20boys ranging from 3.8 years to 12.3 years of age. The variables used in this study were chronologic age, the amount of the eruption and formation of permanent canine, first premolar and second premolar, the amount of the root resorption of the deciduous canine, first molar and second molar, the amount of mandibular development. Based on the measurements, the product-moment correlation coefficients, partial correlation coefficients where the chronologic age was fixed, and the coefficient of determination between these variables by multiple regression analysis were calculated.
As a result, the partial correlation coefficients which eliminated the influence of chronological age indicated that the amount of root resorption of deciduous teeth and the eruption of succedaneous teeth revealed the highest correlation. The amount of root resorption of the predecessors was, therefore, found to be one of the important factors which could assess the amount of the eruption of succedaneous teeth.
Furthermore, multiple regression analysis was performed with the amount of eruption as a dependent variable and the amount of tooth formation, chronologic age, the square of the age, the cube of the age, the amount of root resorption of the deciduous teeth, and the amount of mandibular development as independent variables.
As a result, compared to the study by Kindaichi who made the polinominal regression analysis between two variables, a slightly higher coefficient of determination was obtained in the present study.
Eventually, it was found that the eruption of succedaneous teeth could be expressed as the combination of various contributing factors.

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The purpose of this study was to evaluate the influence on gingiva using DPH therapy in infants. The subjects were 18 epileptics and 20 normal infants as controls with clinically healthgingiva who were examined for the pocket depth, the plaque index, and the gingival bleeding index (GBI). The interrelationships among pocket depth and DPH dose, term of dose, DPH concentration in plasma were investigated.
The following results were obtained.
(1) The plaque index in the DPH group was higher than that in the control group.
(2) The pocket depth in the DPH group was deeper than that in the control group. The pocket depth in the DPH group was deeper in the posterior area.
(3) Almost all the children with high GBI were in the DPH group.
(4) No interrelationships were obtained among pocket depths in the DPH group with clinically health-gingiva and DPH dose, term, DPH concentration in plasma.

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How experimental caries should respond to animal bodies with or without thymus was examined by using mice and nude mice. The animals were given antibiotics for a period of three days in order to depress the oral micro flora. One day after depression with antibiotics, the animals were administered Streptococcus mutans PS-14 and 6715 once every two days until the establishment of the infected bacteria. All the animals were bred for 105 days and fed a cariogenic diet (2000)during the experimental period. After being injected with Nembutal, mouse blood was collected by means of cardiac puncture. Serum was separated and serum immunoglobulins were measured by means of the single radial immunodiffusion method. No differences between the control groups and the infectious groups in both mice and nude mice were detected in serum IgG, IgA and IgM concentrations.
In the nude mice, particulaly, plaque samples taken after sacrifice were cultured for measuring the mount of viable S. mutans. The upper and lower jaws were cleaned and then stained, and caries were scored using the Keyes method. Extensive carious lesions were produced in nude mice, but no differences during serotypes were detected in the caries score and in the mount of viable S. mutans at the time of sacrifice.

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Diazepam has been widely used as a sedative in dental practice. The effect of intravenous diazepam administration is rapid and reliable. However, the intravenous technique is difficult when it is used with uncooperative children or handicapped patients. Intrarectal diazepam administration is simple and reliable for these patients.
This study was carried out to investigate the effectiveness of intrarectal diazepam administration in dental treatment for uncooperative children and handicapped patients.
The study comprised of 35 uncooperative and handicapped patients, aged from 5 months to 20 years. There was a total of 66 dental treatments among the 35 patients.
The following results were obtained:
1) The technique for intrarectal diazepam administration was easy and the mean time spent for the administration was 1 minute and 1 second. A mean onset time was 8 minutes and 42 seconds and the interindividual differences were small.
2) The evaluation of the sedative effect during dental treatment resulted in the following 4 types: markedly effective 24.2%, effective 37.9%, slightly effective 22.7% and ineffective 15.2 %.
3) Diazepam was found to lessen markedly the involuntary movement associated with cerebral palsy and to be effective for the anxiety of patients who had slight mental retardation. However, diazepam was not effective for patients who had severe mental retardation or healty patients who were less than 3 years old.
4) Immediately after the administration of diazepam,4.5% of the patients passed stools. On the way home,55% of patients had difficulty in walking. During the night after the treatment,25% of patients complained of a vague feeling of discomfort and difficulty in falling asleep and 20% lost their appetite. On the next day after the treatment,15% complained of a vague feeling of discomfort and 10% lost their appetite.

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The composite resin jacket crown (called the CR crown) for primary anterior teeth has shown excellent clinical prognosis as well as a favorable esthetic effect, is easy to handle and has good mechanical properties. Nevertheless, we occasionally encounter cases of severe attrition of the natural primary tooth structure from opposing the composite resin jacket crowns.
In this report, worn surfaces of exfoliated primary incisors from opposing composite resin jacket crowns and from opposing natural teeth were investigated comparatively with an optical stereo-microscope (×25) and a scanning electro-microscope(×1000), We observed then the artificial wear surface of the tooth structure using the regular type composite resin and micro filler type resin.
The findings were as follows: In comparison with the undulated surface contour of the naturally worn tooth structure, the surface of the tooth structure was very smooth and covered with a number of fine scratches in the tooth opposite the composite resin jacket crown. The widths of these scratches were about 3 to 7 cm. When comparing the artifical wear surfaces using the regular composite resin with those by using micro fillered composite resin, the latter showed a smaller amount of wear.
In conclusion, it is assumed that the excessive wear of primary anterior teeth by opposing composite resin jacket crowns would have been due to the nature of the filler contained in the composite resin.

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From the clinical point of view, it is important to know the dentin thickness between the cavity base and pulp chamber. The purpose of this study was to investigate the relationship between the electrical resistance and the thickness between the cavity base and pulp chamber in deciduous teeth.
Fifty-two newly extracted sound deciduous anterior teeth were subjected to mesurement of electrical resistance and to examination of serial specimens. Also the electrical resistance was mesured at 443 points.
The findings were as follows.
1) The teeth showed electrical resistance values over 1000 kΩ in the enamel cavities.
2) The electrical resistance values showed mostry under 600 kΩ, and showed a gradual decrease as the thickness of dentin decreased in the dentin cavities. However the great variation (1SD: 320μ) of the thickness of dentin at each electrical resistance values was shown.
3) The small variation (1SD: 180μ) of the thickness of the materials, the secondary dentins of which were resected, at each electrical value was shown. Also the relationship between the electrical resistance (xkΩ) and the thickness (yμ) of this materials was as follows. y=215.9 log(x)-647.0 (r=0.986)

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A girl,12 years and 1 month old, was diagnosed as having partial anodontia accompanied by anhidrotic ectodermal dysplasia, and the following findings were obtained.
1. The characteristic triad consisting of hypohidrosis, hypotrichosis and partial anodontia was observed.
2. 18 permanent teeth were congenitally absent and the growth of the alveolar bone was poor in the area where the teeth were absent.
3. According to the cephalometric analysis, the maxilla was underdeveloped.

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The Silver-Russell Syndrome refers to primary dwarfism and is characterized by shortness of stature, asymmetry of the body, triangular shape of the face and variation in the pattern of esxual development.
This report concerns two cases of Silver-Russell Syndrome in 2 girls 6 years 3months and 6 years 1 month of age.
Observation were made from the dental point of view and the developmental changes.
The findings were as follows.
1) In both cases,“catch up growth”was observed by means of developmental evaluation of the wrist bone age.
2) It was suggested that a maloccluusion was caused by a discrepancy of the growth inboth jaws (the mandibule is smaller in relation to the mawilla). This waas special dental characteristic of this syndrome.
3) Severe dental caries were not a dental characteristic habits fo this syndrome, but it was suggested that bad food was due to anxiety about the short stature and was one of the indirect cause of severe dental caries.
4) Abnormal findings in regard to the function of the masticatory muscles were not observed.

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Relatively many case reports on a geminate or fused tooth were found in the literature, but those on a three-fusion tooth were rare. Two cases of a three-fusion tooth, containing supernumeraries, were found in a boy and a girl, patients at Nihon University Dental Hospital at Matsudo. The boy was 2.8 years old (Case I), and the girl was 4.7 years old (Case II) at the time of the treatment.
From examining the history and clinical observations, the following findings were obtained.
(1) Family history: Abnormalities in the form of the tooth crowns were found among the family members with both Cases I and II.
(2) Medical history: Mother of Case II failed to take enough food during her early pregnancy.
(3) Intraoral findings: The three-fusion tooth of Case I consisted of the maxillary right deciduous central and lateral incisors and a supernumerary tooth. Lingual version was observed with the mandibular right deciduous lateral incisor of Case I, and the crowding of teeth was observed around the anterior portion of the same subject. The three-fusion tooth of Case II consisted of the mandibular right deciduous lateral incisor, canine, and a supernumerary tooth. The fusion of the mandibular left deciduous lateral incisor and canine and a serious overbite were also observed with Case II.
(4) Radiographic findings: The permanent successor was observed at the deciduous central incisor with Case I, and at the deciduous canine with Case II. The permanent successor at the fused tooth of the mandibular left was also recognized with Case II.
The two cases are being clinically observed at present. Further morphological and histological investigations will be made after these fused teeth fall off.

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1. A girl,4 years and 9 months old at first visit, had an already erupted 4 and which was extremely loose.
2. The looseness of 4 necessiated its removal. The examination of the ground section and a scanning electron microscopic observation revealed enamel hypoplasia.
3. An X-ray micro-analysis revealed no abnormalities.
4. A pathohistological examination of the soft tissue under the tooth showed chronic granular inflammation.

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The electric caries-detecting meter (Caries-meter) is widely used to diagnose caries regions of teeth. In our clinic, we have developed a system of diagnostic procedure ranging extensively from prevention to endodontic treatment of deep caries, by basically utilizing the caries-meter (Caries-meter-A).
In this report we clinically tested the newly designed caries-meter-L which is handy and specially designed to indicate the four levels of electrical impedance by different colors of light. The comparison was made between the actual value of electrical impedance measured by an analogue type cariesmeter (Caries-meter-A), and the level of color shown by Caries-meter-L.
The results of the clinical test were as follows:
1) As for the rate of coincidence of the indication of light to the range of electrical impedance, the green (over 600 kΩ) area was 100 percent, the yellow (251-599 kΩ) area was 88 percent, the orange (18.1-250 kΩ) area was 99 percent, and the red (under 18.0 kΩ) area was 100 percent. The actual electrical impedance in the disaccordant cases approximated the maximum and minimum values which were set up corresponding each color light.
2) There were 4 cases with simultaneous lighting of two adjacent lamps. The electrical impedance in these cases showed the approximate value to the borderline value which was set up corresponding to each light.
3) Together with the fact that this newly designed caries-meter is handled without difficulty, from the results of this study indicating high accordance between the indication of the lighting color and electrical impedance, it may be concluded that the Caries-meter-L is shown to be practical for clinical use.

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The purpose of the present study was to estimate the topical anesthetic effects of Beezocaine Jelly (20 w/w%,, Ethyl aminobenzoate) on gingiva of children who visited the department of Pedodontics of Osaka Dental University Hospital.
The study was performed by comparing clinically accepted Beezocaine Jelly (62 children) and inactive placebo (26 children). Topical anesthetic effects of Beezocaine Jelly showed 74.2% and a Significant difference (P<0.05) was fond between the study and control. No toxic responses have been found from the use of Beezocaine Jelly.
The results of the study indicate that Beezocaine Jelly has been used successfully for children as a topical anesthetic agent.

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