For examinating the relationship between the attachment of the superior labial frenum and midline diastema, the propriety of frenumectomy and the period of tis appearance, we measured the distance from the frenum attachment to the summit of the interdental papilla, in 498 children aged from two to fourteen years, and had visited the Pedodontics, School of Dentistry, Iwate Medical University.
1) The distance of the frenum attachment increased remarkably at each age between the ages of two and four years (3.0∼4.0 mm) and between the ages of six and ten (4.0∼5.0 mm), and it scarcely changed between the ages of four and six (4.0 mm). It seems that the attachment of the frenum standardizes between the ages of eleven and fourteen years (5.3∼5.7 mm).
2) The attachment of the labial frenum in children five to seven years old, the period when they are changing anterior teeth, showed no differences betwe en the group with permanent central teeth and the group with deciduous central teeth.
3) The distance of the frenum attachment, having the diastema at five years, was shorter than when there was no diastema, and in the other age groups there was no significant distance.
4) Concerning the distribution of the distance of the attachment, the group with the deciduous central teeth in children 2-7 old were distributed bet ween 2.1∼6.0 mm and the group with permanent central teeth in children eight to fourteen years old were distributed between 3.1∼7.0 mm, therefore the group with the permanent teeth showed a greater range of distribution.
5) Frenumectomy should be administered at a low age, and the extent of the interference, should be examined until about the age of 9 and the progre ss, observed after which it can be decided whether or not to excise the frenum.

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There have been few reports on dental care for the autistic child which the authors consider to be very necessary to promote.
The authors had an opportunity, in a class for the psycho-social rehabilitation of the patients, to guide the patients and their parents in the maintenance of proper oral health. Taking advantage of this opportunity, we examined the present status of dental caries and daily home care for promoting the oral health of the children and the effects of health guidance on the behavior of the parents toward the oral health of the children.
The prevalence of dental caries in the autistic children did not seem to be significantly higher than that in normal healthy children. Present dental care practiced at home by the patients and their parents did not differ from that practiced by healthy children and their parents. Parents of the patients readily accepted the oral health guidance and took a positive attitude to improve their daily home practices.
These results suggest that proper and systematic guidance concerning dental health care would provide effective prevention of dental caries of the autistic child.

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Post-eruptive changes in human dental enamel were examined by polarizing microscopy, microradiography, and an electron probe X-ray microanalyzer.
Eleven caries-free permanent first premolars which were extracted for orthodontic dontic purposes from 6 patients who were in three groups,11,13, and 18 years of age were examined. Buccolingual sections were ground down to approximately 100 μm thickness.
In the 11 year old age group,microradiography showed radiolucency in an approximately 70 μm surface layer which corresponded to positive birefringence in water with polarized light,and an electron probe X-ray microanalyzer showed a 6 to 7 % Ca and P decrease in an approximately 100 μm surface layer which corresponded to positive birefdngence in air.The most surface layer of 15 to 20 μm showed negative bireffingence,radio-opacity,and not as much of a decrease of Ca and P as did the inner layer. Therefore, it is obvious that positive birefringence fringence with polarized light is not due to a difference of crystal texture but to under calcification. In the 13 year old age group, the depth of the layer which showed positive birefringence, radiolucency, and decrease of Ca and P decreased. In the 18 year old age group, no layer of positive birefringence, radiolucency, and no decrease of Ca and P was seen. This indicated completion of calcification, i.e. fully mature enamel.
From these findings, it is speculated that at first, after eruption, the most surface layer of immature young enamel is calcified by the effects of saliva, food, drinks etc., and then from the bottom of the subsurface inner layer the calcification increases. Finally, the enamel will complete calcification, and develop into fully mature enamel.

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Previously, Dr. Nishimura reported that the elimination of the excess Ca and P in the tooth is an inevitable step for the accurate quantitative analysis of Cd, Zn, Pb, and Cu. This procedure, achieved by metal column chromatography using a tartrate buffer solution, is still required to eliminate the buffer itself prior to the measurement of the trace element by means of the flameless atomic absorption spectrophotometer.
Thus, Dr. Shinji reported that an improved buffer system for the separation of trace elements was proposed by using a gradient mixture of a volatile solution of hydrochloric acid and acetone (0.64M-HCl,40-86% acetone). Macroporous cation exchange resin MP-50 was used as a filler.
The author, therefore, made further examinations and found better resolutions by using macroporous cation exchange resin Amberlite-200 for the analysis of Cd, Zn, Pb, and Cu in human deciduous teeth. The following results were obtained:
1) The cation exchange resin Amberlite-200 exhibited two or three times better separation and concentration abilities of respective trace elements than the cation exchange resin MP-50.
2) After separation of trace elements, no ashing of the buffer was required for accurate analysis. Calibration curves of trace elements showed a good linear function, up to 50 ppb for Cd and Zn, and also up to 100 ppb for Pb and Cu.
3)Minimal dctectable amounts of those trace elements with the concentration of 6.25 PPb were calculated as 9.0×10^-13g,3.2×10^-12g,2.7×10^-12g,5.5×10^-12g for Cd, Zn,Pb,and Cu,respectively.
4)The recovery rates of trace elements were determined using the method of a standard addition with enamel,dentine,and a standard solution which obtained extremely good values,respectively.
5)The mean values(μg/g)of the trace element in enamel and dentine were determined as 0.83±0.558 and 0.30±0.222 for Cd,176.43±32.894 and 127.53±14.708 for Zn,13.85±10.227 and 26.34±22.440 for Pb,3.92±3.413,and 2.49±2.465 for Cu,respectively.
From the above results, it was shown that the use of a gradient system using a mixed solution of hydrochloric acid and acetone, is an extremely effective means for the quantitative determination of trace elements in deciduous teeth, particularly by utilizing the flameless atomic absorption spectrophotometry method.

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Abstract: For the purpose of investigating morphological changes of the gingival epithelium and lamina propria during the eruption of teeth, a total of 45 subjects ranging in ages from 3 to 12 years was examined. The subjects were divided into 4 groups depending on their stages of tooth eruption. The sample gingivae were examined with the ultrathin section method and with the freeze-fracture method. The following were the results of the present investigation.
1) Microscopic faults or separations of the collagen fibers in lamina propria were observed along with the eruption of the teeth.
2) The basal lamina was observed until the fusion of the reduced enamel epithelium and oral epithelium. Right after the Fusion, however, the basal lamina, together with that of the reduced enamel epithelium, rapidly disappeared. Th e hemidesmosome, as was the case with the basal lamina, did not disappear until the later stages of tooth eruption.
3) The expantion of the intercellular space was observed from the early stages of tooth eruption.
4) Along with the advancement of tooth eruption, the number of desmosomes decreased, and the tonofilament bundles extending toward the desmosomes were separated and shrunken, but the desmosomes continued to exist until right before the eruption of the tooth.
5) Well-developed gap junctions were observed around tip portions of the cytoplasmic projections of the adjacent cells, and less developed gap junctions were observed during the later stages of tooth eruption. This suggests that the gap junctions begin to degenerate from the early stages of tooth eruption.
6) Notable changes observed with the spinous layer were the fluctuation of the tonofilament bundles in the cytoplasm. The tonofilament bundles extending toward every direction in the cytoplasm decreased in number as well as in length along with the advancement of tooth eruption, and those attached to the desmosomes were separated around the surface of the cells. The long, well-developed tonofilament bundles were observed all over the cytoplasm of the cells in the period of partial eruption of the tooth crown, as was the case with the epithelial cells which were not affected by tooth eruption.
7) Many membrane coating granules were observed in the upper part of the spinous layer and in the cytoplasm and intercellular space of the granular and cornified layers. Those granules were greatly reduced in number right bef ore or right after the fusion of the oral epithelium and the reduced enamel epith elium along with the advancement of tooth eruption.
8) Every cornified layer examined was parakeratinized, which was different from the cornification of the epidermis revealing keratin patterns. The corn ified layers increased in number right before the eruption of tooth, but all the cornified layers exfoliated in the oral cavity when a tooth erupted.
9) With the freeze-fracture method, it was observed that the intramembranous particles observed on PF face and EF face tended to be loca lized along with with the advancement of tooth eruption.

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1) A case of Epulis fibromatosa was encountered in the interdental papilla of AB in a girl,four years and two months old.This occurrence was considered relatively rare in respect to the age and frequency of occurrence.
2) It was considered that non-odontogenic fibroma occurred peripherally in the gingiva and took the form of Epulis.3) Histopathologically it showed the findings of a benign fibrous tumor consisting mainly of markedly proliferated collagen fibers. Inflammation was hardy observed and no nervous fibers were observed to be scattered.

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The case for the impacted permanent teeth caused by the supernumerary teeth on the eruption path has been often observed. However, the impaction of the deciduous teeth caused by the anomalies in the position of permanent teeth from an embryological point of view has not been reported on yet.
As we recently encountered a permanent tooth above the second deciduous molar, we reported on the clinical findings of the oral cavity and the histological findings of the permanent tooth.
A 5-year-old boy was referred to the Pedodontic Clinic at the Tohoku University Dental Hospital. His mother had complained about delayed eruption of his lower right second deciduous molar.
There was nothing unusual in his past medical and dental history. The findings from the oral examination revealed a normal condition except for the absence of the lower right second deciduous molar. An x-ray examination revealed that the lower right second deciduous molar was impacted deeply. Above this molar there was a tooth-like radiolucent object. The lower right second bicuspid was not observed on the radiograph.
The tooth-like object, above the lower right second deciduous molar, was extracted. A button was attached to the lower right second deciduous molar as well as were brackets to the deciduous molars and cuspids by the Direct Bonding System. In order to induse eruption of the lower right second deciduous molar, an arch wire was attached to the brackets.
The extracted object was found to be a small cone-shaped tooth with an incomplete root. The Retzius lines of the tooth were observed but not the neonatal line on the enamel specimen.
The tooth germ of the lower bicuspid is usually located on the lingual side of the deciduous molar at birth, and subsequently moves to the occlusal side of the deciduous molar. Finally it locates below the bifurcation of the preceding deciduous molar.
For the reasons mentioned, we concluded that the tooth germ of the second bicuspid remained above the second deciduous molar for no apparent reason.

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Morphological changes of the occlusal facets with increasing age were investigated in children at the initial stages of the deciduous dentition period and in those immediately prior to the period of when changing to permanent teeth, to clarify the interrelation between dental attrition that develops as the child grows and the morphologic characteristics of the deciduous dentition. The interrelationships of vertical and horizontal relationships of the deciduous dentition at these stages were also investigated.
The materials were longitudinal study models obtained from children with normal occlusion.
Fifty children with no carious teeth in whom the morphologic changes could be followed serially from early IIA stage to late IIA stage were studied, with the results leading to the following conclusions:
1. The frequency with which standard occlusal facets appeared increased progressively with age, the increase being statistically significant in respect to the mesial and distal incisal margins of the upper deciduous canine and those of the lower deciduous canine.
2. The area of standard occlusal facets increased progressively with age. Differences in tooth crown form, state of the eruption site and sequence of eruptio n seem to have a bearing on the areal changes.
3. The dental crown length decreased with advancing age and was prone to diminish as the occlusal facets area increased.
4. No significant difference was observed between the right and left sides of the dentition with respect to the frequency of appearance of occlusal facets, face ts, dental crown length and degree of decrease in dental crown length.
5. The horizontal changes of the deciduous dentition are related to the attrition of the lower deciduous canine.
6. Observation of the features of lower deciduous canine attrition may provide a clue to the evaluation of the occlusion of deciduous dentition and also fa cilitate estimation of its relationship to the permanent dentition to some exte nt.
7. It was noted that the attrition of deciduous teeth took place in a somethat different manner than the attrition of permanent teeth. The disparity might be attributed to the morphological difference between deciduous and perman ent teeth as well as to the difference in occlusion between children and adults.

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In cases of handicapped children, it is sometimes necessary to perform comprehensive dental treatment under the conditions of general anesthesia, including pre-operation and post-operation anesthesia. Also of importance is blood gas analysis as respiratory function test, for which, however data acquisition is often prevented by the excitement and crying of the patients.
The present authors obtained data of blood gas analysis together with the emotional responses from 33 mentally retarded children who underwent preoperation administration of general anesthesia, selected from handicapped children without respiratory and circulatory systems diseases.
The following findings were obtained.
1) Respiroration rate increased in groups [Cry (+) and Cry (_??_)] who cried during exsaguination.
2) The tital volume of ventilation decreased, compared with pre-exsaguination, in groups [Cry (+) and Cry (_??_) who cried during exsaguination.
3) The volume of ventilation per minute increased, compared with pre-exsaguination, in groups [Cry (+) and Cry (_??_)] who cried during exsaguination.
4) The blood gas analysis of group [Cry (_??_) who did not cry revealed that, in contrast with the group who did not cry during exsaguination, pH increased by 0.12 and PaCO₂ decreased by approximately 10 mmH.g

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The authors investigated histopathologically the effects on deciduous pulp of water-settable cement “ UNIDENT ”, using 45 nonexposed teeth and 3 exposed teeth of 13 young dogs, over periods of 1 and 3 days or 1,2 and 4 weeks after the operation. The results obtained from this study were as follows.
1) Pathologically,33 cases (73%) were evaluated as “ Good ”,10 cases (22%)“ Satisfactory ” and 2 cases (5%) “ Poor ”.
2) The pulp response was mild until 2 weeks after the operation. However after 4 weeks, there was little response.
3) Cases with poor results had only a thin of the remaining dentine. (less than 30 u thickness of the remaining dentine).
4) Secondary dentine formation was observed for only 4 weeks after treatment with little forming.
5) Pathologically,1 exposed pulp was evaluated as “ Satisfactory ”,2 cases “ Poor ”. In cases of exposed pulp the reaction was mild. We concluded that the water-settable cement “ UNIDENT ” caused little irritation to the dental pulp.

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Radiation therapy upon the young is decreasing. It is, however, sometimes used for the treatment of malignant tumors, and that could cause various defects in some cases.
This report describes a case we encountered in which tooth formation and growth of the dentofacial area had been affected by irradiation at the age of four months.
The patient was a girl first examination was when she was thirteen years and seven months old.
The purpose was recovery of the masticatory function and her facial features. Her case record revealed she had been diagnosed as reticulosarcoma when she was four months old, and had been cured by radiation therapy with 5500 rad ⁶⁰C-γ ray.
She was of slender build,and oral examination revealed Hellman Dental age lV A, remaining teeth _??_formation defects found in _??_and a medium tremble noticed around _??_. Also a hard swelling,about the size of the tip of the finger, was felt around a mucobuccal fold in upperleft front molar.
X-ray examination found loss of all the first and the second premolars. Plaster model analysis showed a construction of the upper jaw and mandibular as well as narrow dental arch. Gephalogram analysis showed the mandibular was rotated toward the upper front due to a lack of height of the middle face.
In order to obtain histopathological findings,we made 40μ thick ground sections of nondecalification in the lower lateral incisor.
A microradiogram was performed and an observation was carried out.As a result of this, a construction of enamel was recognized where the formation defect appeared, and a clear permeable image which covered the area from the border of the enamel and ivory to the enamel cuticle was found.
As a result of histopathological examination of the swelling conducted at the same time as the extraction of the upper front teeth, this patient was diagnosed as melanoma and now taking an immunization treatment. As the progress is fairly good, a denture for the recovery of the facial featuers was made and set, and is now under observation.

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This study was to discover the factors that cause the irregular alignment of the incisors during the period of the; reruption. The materials were plaster models of 20 maxillary arches and 21 mandibular arches. They were classified into three groups depending on occlusion --1) normal occlusion group (10 maxillary and 7 mandibular arches),2) “flaring”group (5 maxillary and 6 mandibular arches), and 3) crowding group (5 maxillary and 8 mandibular arches).
The phenomena observed in this study were the relationships between the alignment of the incisors and the position of erupted permanent incisors, difference of the sum of the mesiodistal crown diameter between four deciduous and four permanent incisors, developmental increase of the intercanine width and physiological interdental spaces in stage of II A Hellman's dental age.
The results are summarized as follows:
1) Of 43 cases with normal initial eruption of the lateral permanent incisors,13 cases were evaluated as having malposition of fully-erupted inciso rs.
2) However, of the 36 cases with abnormal initial eruption of the lateral permanent incisors,2 cases were evaluated as having normal position of the ful ly-erupted incisors.
3) The sum of each mesio-distal crown diameter of the four deciduous incisors, and of the four permanent incisors in the normal occlusion was slightly smaller than the sum in the “flaring group ”, and in the crowding group.
4) The difference of the sum of the mesio-distal crown diameter between deciduous and permanent incisors in normal occlusion was 7.6 mm in the maxillar y arches, and 6.0 mm in the mandibular arches on the average. The difference in the “flaring group ”, and crowding group was larger than that of the normal occlusion.
5) The intercanine width of the maxillary arch in stage II A of Hellman's dental age and the period of the initial eruption of the lateral incisors was larg er in the crowding group, the normal occlusion group, and “the flaring group ”in that order. The intercanine width of the mandibular arch was larger in the crowding, “the flaring group ”, and the normal occlusion in that order.
6) There was no marked difference in the developmental increase of the deciduous intercanine width among the normal occlusion group, “the flaring group ”, and the crowding group. The deciduous intercanine width was 3.3 mm in the maxillary arch and 2.6 mm in the mandibular arch, on the average.
7) The difference of the mesio-distal crown diameter between the deciduous and permanent incisors was not statistically correlative to the devel opmental increase of the deciduous intercanine width.
8) There was statistically a significant difference in the physiological interdental spaces between the crowding group and the normal occlusion grou p in both the maxillary and mandibular arches. The sum of the physiological spaces was larger in the normal occlusion group than the crowding group.

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The purpose of this study was to observe the sequence of the eruption of the permanent teeth longitudinally, using 1607 serial plaster models of maxillary and mandibular dental arch taken every three months. The materials consisted. of a total of 60 cases which included 31 with normal occlusion, and 29 with malocclusion (6 with maxillary prognathism,10 with bimaxillary prognathism and 13 with crowding).
The phenomenon observed in this study was the sequence of the eruption of all permanent teeth except the third permanent molars, and specifically in detail,1) the sequence of eruption and the occlusion of the first molars and the central incisors,2) the sequence of eruption and the occlusion of the four incisors,3) the sequence of eruption and the occlusion of buccal segments, and 4) the sequence of eruption of the second premolars and the second molars.
The results are summarized as follows:
1) Not one case out of 60 cases showed the same sequence of eruption of the 28permanent teeth, the first-emerged tooth to the second molar erupted.
2) The mandibular central incisor erupted earliest in 46.7 % of the cases, the mandibular first molar in 45.0%, and the maxillary first molar in 8.3%.
3) Regarding the sequence of the first molar and the central incisor, Type (1→6 was found in 30.0% of the cases, and Type (6→6) in 23.3%. Concerning the occlusion, normal occlusion showed Type (6→) and Type (1→) with the same percentage.
4) Regarding the sequence of eruption of the four incisors, Type (1→2→1→→ 2) was found in 58.3 % of the cases. Both normal occlusion and abnormal occlusion showed Type (1→2→1→2) in many cases.
5) Regarding the sequence of eruption of the maxillary buccal segments, Type (4→3→5) was found in 38.3% of the cases, Type (3→4→5) in 20.0% of the cases and Type (4→5→3) in 15.0% of the cases. Normal occlusion showed Type 4→3→5) in many cases. Maxillary prognathism did not show a case with Type (4→5→3). Crowding showed comparatively many cases with Type (4→5→3).
6) Regarding the sequence of eruption of the mandibular buccal segments, Type 3→4→5) appeared in 70.0 % of the cases. All of the variations of occlusion showed many cases with Type (3→4→5).
7) Cases in which the second molar erupted earlier than the second premolar were not found so frequently unilaterally in the maxillary arch (2.6%) of the cases, unilaterally in the mandibular arch (13.6%) of the cases, and bilaterall y in the mandibular arch (8.5%) of the cases.

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Amalgam has come into wide use as a filling material for primary molars. Recently, however, the mercury content of amalgam has given rise to a variety of problems. At the same time, composite resin is considered by many to be unsuitable for filling molars because of important questions raised concerning its resistance to abrasion due to masticatory stress or other external forces, as well as concerning its edge strength.
The newly developed K-G composite resin for molar fillings (TMM-Si₃N₄: Kanebo) has a completely different composition than the Bis-GMA composite resin that has been in use to date. K-G composite resin has a mechanical strength and adhesive qualities comparable to those of amalgam.
To test the use of K-G composite resin as a m o lar filler, we treated 70 patients at the Pedodontics Clinic of Nippon Dental University Hospital. A total of 105deciduous molars were filled with K-G composite resin and clinical examinations of the filling material were made during the 2-5 months that followed. The following findings were obtained:
1) Complications developed in 22 out of the 105 teeth filled (21.0%).
2) Seventeen of those cases (16.0% of total) involved complications with the filling material, primarily accounted for by marginal fractures, body fractu res or loss of fillings.
3) Abrasion of the filling material was found in only one case out of 16 class-I simple cavities. No cases of abrasion were found amound the class-I co mplex cavities or the class-II cavities treated.
4) They were no cases of spacing between the filling material and the dentine or of discoloration.
5) Complications in the tooth substance were found in six cases (5.7%). Nearly all of these were recurrent cavities.
6) Complications involving the pulp or gingiva were found in 4 cases (3.8%). All of these were class-II cavities.
Based on these findings, K-G composite resin appears to make up for the deficiencies of amalgam and thus has high clinical value as a filling material for primary molars. There is still room, however, for additional research concerning the anatomical characteristics of primary molars and physiological attrition. Therefore, we intend to continue our investigations.

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The present study was so designed as to evaluate the influences of the experimental occlusal interferences on masticatory muscles of children by means of electromyograms (EMG) on tonic neck reflexes.
Eight children, who were in Hellman's dental stage IIA, were examined. A metal overlay approximately 350, μm thick was capped on one side of the 2nd deciduous molar of mandible. The EMG of temporal and masseter muscles were then recorded sequentially, before and 7 days after placement and 7 days after removal of the overlay.
The results obtained in the present study were as follows:
1) All subjects except one complained of some unpleasantness for after placement of the metal overlay and none of them complained of pain.
2) Increased muscle activities ipsilaterally on the interference side, with the metal overlay, were found in 5 subjects out of 8.
3) In regard to the synchronism found in the EMG, onset of muscle activity on the interference side preceded that of the other side, and this tenden cy was likely to be prominent in the masseter muscle.
4) Influences of occlusal interferences on masticatory muscles evaluated both with amplitude and synchronism of muscle activity were found in 7 sub jects out of 8, and susceptibility against interferences may differ individually.

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The subjects were 1255 children (603 boys and 652 girls), who had visited the Pedodontic clinic of Toyota Hospital during the period from June 1979 to February 1981.
The purpose of this investigation was to discover the actual condition and the treatment procedures of the patients who visited the Hospital.
The findings were as follows:
1) The average of age of 603 boys was five years and six months and of 652 girls was five years and six months.
2) Complaints of pain were recognized in 316 children (25.2%).
3) Complaints of swelling were recognized in 154 children (12.3%), while complaints of pain and swelling were recognized in 107 children (8.5%).
4) 27.9% of the children were mentaly or physically handicapped children.
5) Treatment procedures were as follows;
803 children with fillings (6 4.0%)
356 with tooth extractions (28.4%)
303 with prevention (24.1%)
287 with pulp therapy (22.9%)
236 with root canal treatment (18.8%)165 with complete veneer crowns (13.1%)
115 with space maintenance (9.2%)
85 with surgery except extra ctions (6.9%)

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The condition of the proximal caries lesions on deciduous molars were examined using the X-ray films which were taken from the patients who had been referred to our clinic. The relationships between X-ray findings and the clinical diagnosis were then investigated.
The following conclusions were obtained.
1) The condition of the proximal caries lesions on deciduous molars. Compared to the previous reports, higher ds rates were shown on the mesial surface of the 2nd deciduous molar and the distal surface of the 1st deci duous molar. Especially in the lower 1st deciduous molar, the rate of the caries on the distal surface was the highest, and the rate of severe caries was also com paratively high. In the mesial surface of the 2nd deciduous molar and the distal surface of the 1st deciduous molar, the rate of severe caries increased w ith age on both jaws.
2) The rate of the clinical caries detection with respect to the X-ray findings. Concerning the early caries group which showed radiolucency lim ited in the enamel, the rate of detection was only about 10%. The rate of detection, however, tended to be higher in the severe caries group. However only the case of the distal surface of the upper 1st deciduous molar showed the low er rate of 45.6%.
3) The relationships between the proximal caries and total caries condition. The dmft and dmfs index tended to be high in the patients who had proximal caries lesions. The high value was especially shown in the patients w ho had severe caries lesions. The same tendency was seen between the mesial surf ace of the upper 1st deciduous molar and the dmfs index of anterior deciduous teeth.
4) The relationships between the proximal caries and the occlusal caries. In accordance with the severity of the proximal caries, the occlusal caries which were diagnosed C₂ or C₃ increased except with respect to the upper 1st deciduous molar.

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The subjects were 200 handicapped children (120 boys and 80 girls) who had been referred to our clinic between 1976 and 1980.
Their ages ranged from 3 to 6 years and they were classified into 6 groups according to their disorder.
The oral condition and the type of treatment were examined at each recall time.
The relationships were then investigated. The findings were as follows.
1) Over approximately 90% of the patients were referred again to our clinic at every recall time (lst-4th).
2) The average number of newly decayed teeth was 2.38 on the 1st recall time, but it decreased from the 2nd recall time.
3) Application of the Ag(NH₃)₂F and restorative treatment were practiced at similar percentages on the 1st recall time, but the restorative treatment tende d to increase from the 2nd recall time.
4) As to the rate of the teeth which needed re-treatment, the group restored with metal crowns showed a lower rate (21.9%) compared to the others (nearly 40%).
5) There were no differences based on age or type of disorder.

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The Stevens-Johnson syndrome was first described in 1922 by Stevens and Johnson. This syndrome is one of the mucocutaneous-ocular syndromes that is characterized by eruptive fever associated with oral and eye manifestations. The etiology is still unknown.
Although there are many reports concerning this syndrome, no report concerning the oral manifestation except for stomatitis has been published. We investigated a case of Stevens Johnson syndrome, in which short roots were observed in most of the permanent teeth.
The patient (a twelve-year-old boy) diagnosed as a Stevens Johnson syndrome visited the Pedodontic Clinic of Osaka University Dental School, and was examined from the dental point of view.
The findings were as follows:
1)All permanent teeth _??_ had erupted by tthe first visit. Colorings and mild hypoplasia were observed in the cervical area of all teeth, and except for _??_, cervical caries were also found.
2)Besides _??_, all permanent teeth had short roots that were shaped roundd and dull.
In this case, it was suggested that the occurrence of the short roots had resulted from the disturbance in the growth of the roots or the retention of their development associated with Stevens Johnson syndrome.

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The first report of primary immunodeficiency disorders was published by Bruton in 1952.
In this retort, he described an 8 year old boy with recurrent bacterial infection whose serum upon electrophonetic analysis revealed a lack of γ-globulin,a condition he termed a gammaglobulinemia.
Dysgammaglobulinemia type I reported by Rosen in 1961. Dysgammaglobulinemia charcterized by a decrease in serum content of IgG IgA and increase of IgM was found. Many cases of this are incident to granulocytopenia. We have seen no reports of this case in the area of dentistry. In this case, we performed extraction of teeth under local anesthesia, elimination of necrotic alveolar bone, extraction of many teeth, and many permanent teethgerms under general anesthesia.
The patient was a 3 year old boy. His past history showed recurrent bacterial infection. The white blood cell count was 2800/mm³, with 0 % neutrophils,49% monocyte Read blood cell, Hb, Ht, palatlet, lymphcytes showed normal data. The immunoglobuline count was IgG 260 mg/dl, IgA 35 mg/dl, IgM 380 mg/dl, and the immunoglobuline count of his parents showed normal data. The oral view showed serious gingivostomatitis and developing necrotic gingival tissue. Dental treatment included extraction of 4 deciduous teeth under local anesthesia with 2 % xylocalne, and extraction of 14 permanent teeth,13 permanent teethgerms. Elimination of necrotic alveolar bone under general anesthesia with controlled γ-globuline,antibiotics. There were no complication during the general anesthesia and recovery period.
Septic shock and SIADK were caused by racer on extraction of severely moving 4 deciduous teeth under local anesthesia. The treatment has been completed and the patient is making satisfactory progress, going to the kindergarten now.

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