The aims of this study were to examine the applied status of a biting type FKO (B-FKO) which is a modified Andersen type FKO and to re-examine its effects. The B-FKO was applied with the object of promoting the mandibular growth toward the mesial direction by clenching at the molar segment. The subjects consisted of 21 patients, aged 8-12.3 years,9.8 years on average, all of whom possessed an large over jet (deep bite and protrusion) and to whom the B-FKO had been applied. Numerous parameters such as cephalometric analysis, study casts and treatment record were assessed at the onset of the treatment using the B-FKO, at the removal and 1 year after the removal to determine treatment-related changes due to therapy with the B-FKO.
According to the treatment record, the two objects for employing this appliance were to promote the mandibular growth (PG) and to reduce the over jet or bite. The former has a frequency of 61.9%and with skeletal factors taken from roentgenographic cephalometry while the later has a frequency of 38.1% with the dento-alveolar factor. The appliance has been used during the beginning of a mixed dentition. Attitude on the part of the patients when using the appliance was demonstrated as an important factor which have the benefits on the therapy. Among the changes in the skeletal profile from the onset of the B-FKO to its removal, as for the deference between the onset and the removal ∠ANB, over jet, and ∠LsN′Li decreased significantly. The indications in the skeletal profile at the removal showed however mandibular retrusion still in the subjects alone with the expected effects. The judgment of the effects was made based on changes in the soft tissue profile following therapy. Among the changes in the skeletal profile from the removal of the B-FKO to 1 year after the removal, the diffbrence between the removal and the 1 year after the removal as for ∠LsN′Li increased significantly again. Among the qualitative changes from the onset to 1 year after a time of the removal, ∠SNB, Go-Me, ∠A′N′B′, and ∠LsN′Li demonstrated the tendency to retum.
These findings indicated that the B-FKO was a useful appliance for changing the skeletal profile. The effect was not enough however to improve and to be stable. Moreover, it was suggested that the skeletal profile changes during B-FKO therapy were often not maintained thereafter.

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The purpose of this study was to re-examine the scientific adjustability in chincap therapy based on the actual status of patients using chincap and the skeletal profile change occurring and after chincap therapy. The subjects consisted of 51 patients all of whom possessed an anterior cross-bite (anterior reversed cross-bite). The applied total force with the chincap was 400 g-600 g and the mean treatment period was 30 months. The anterior cross-bite improved after the treatment with chincap therapy and other appliances such as the lingual arch for the changing of tooth inclination. It is suggested that the improvement of anterior cross-bite was related to the change of the mandibular position. This being on effect of the chincap. Although SNB significantly decreased and ANB significantly increased during the chincap therapy, GoPog did not however change significantly. Moreover, SNB was larger than the control and ANB was smaller than the control at the each stage of the therapy, at beginning of the therapy, the end and after one year of the end. As for the qualitative change of the skeletal profile from the biginning of therapy to after the one year of the end, SNB, ANB, U 1-SN, L 1-MP, gonial angle, and facial angle tended to return to the original profile of the patients. Inconclusion, mandibular growth suppression which was the reason for apply the chincap therapy, was not shown in the actual effects in skeletal profile. The mandibular position improved during and after chincap therapy, but mandibular growth suppression did not appear with chincap therapy. It is suggested that the skeletal profile changes during the chincap therapy were often not maintained thereafter.

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We conducted the semi-longitudinal study on the maxillofacial morphology in Chinese female twins. The materials consisted of 330 lateral cephalograms taken from 85 twin pairs from 6 year-olds to 11 year-olds. We compared their maxillofacial growth pattern with those of present Japanese girls, and estimated the degree of genetic factors concerning the pattern by the twin method.
The results were as follows:
1. On the average stature curves, the mean value of the Chinese at the age of 6 was 3 cm higher than that of the Japanese. At and over the age of 7, however, the two lines were almost coincident.
2. The angular analysis showed that there were few differences at both SNA and SNB between the Chinese and the Japanese. On the other hand, the postero-inferior shape of the mandible of the Chinese was already similar to that of the Japanese adult female from Stage 3.
3. The linear analysis showed that the difference in the depths between upper and lower faces of the Chinese was smaller than that of the Japanese, and the mandiblular size of the Chinese was relatively larger than that of the Japanese.
4. Superimposition of their profirograms showed that the anterior profile of the Chinese seemed to be less uneven and more upright than that of the Japanese.
5. At the depths of both anterior cranial base and nasal floor, the heritabilities of the Chinese were between 60 and 80%, while which lowered at Stage 4. Concerning the heights and the shape of mandible, the heritabilities of the Chinese were between 70 and 90%, and which were highest at Stage 5.
6. It is suggested that the main morphological differences on maxillofacial cranium between the Chinese and the Japanese at the mixed dentition stage were the postero-inferior shape of the mandible and its size, and the genetic factors strongly influenced them.

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This study investigated the mesio-distal crown diameters of the primary teeth, primary dental arches, standard values and frequency distribution of primary occlusion in Chinese children (residents of Shanghai). With the cooperation of a kindergarten in Shanghai, China, dental plasters were collected from 43 children (ages ranging from 3-6 years old) with normal primary occlusion. Based on the method reported by the Japanese Society of Pediatric Dentistry, the data were statistically analyzed and compared to those of Japanese children. The results are summarized as follows:
1. The mesio-distal crown diameters of the primary teeth did not differ between Japanese children and those from Shanghai.
2. Compared with the Japanese children, the children from Shanghai tented to show a shorter primary dental archlength.
3. Inter dental spaces of the primary dental arch did not differ among the Japanese children and those of Shanghai.
4. The frequency of the terminal plane relationship to the mesial-step type and the primary canines occlusal relationship to type III was significantly higher in the children from Shanghai than in the Japanese children.

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The purpose of this study was to choose the types of the TMJ dysfunction syndrome which were able to be polarized light therapy (SUPER LIZER). The subjects were 14 Patients (13 females and one male, mean age was 16 years 6 months). We divided them into the following to groups.
Effective group; 7 patients who were cured of TMJ pain after SUPER LIZER therapy.
Non-effective group; 7 patients who remained with TMJ pan after SUPER LIZER therapy.
We compared MR imagings and clinical signs before treatment between both groups. The results were as follows.
1. The prevalence of joint effusion in the non-effective group was statistically higher than that of the effective group, although the prevalence of anterior disk displacement showed no difference between the two groups.
2. The interincisal distance of the maximum opening in the effective group was significantly larger than that in the non-effective group. In the effective group, the contraction term of the TMJ pain had a tendency to be longer compared with the non-effective group.

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Composite resin full crowns which use composite resin and crown forms, have been used for pediatric dentistry. For use as a restoration material, an adhesive ability, aesthetics and easy handing are required. Recently, Geristore® which has the characteristics above besides fluoride releasing Glass ionomer modified composite resin, has been used in the clinic. However, the studies of application for full crown restoration have not yet developed. This investigation evaluates pulpal responses to composite resin full crown restoration using Geristore® on anterior teeth of dogs histo-pathologically.
The following conclusions were obtained:
1. Histopathological study revealed no severe pathological changes. Most of the pathological changes were hyperemia and slight round cell infiltrations. This may have been induced by the cavity preparation itself.
2. Reparative dentin formation was observed in many cases.
3. Pathological changes have decreased and reparative changes have increased with the passing of time.
4. Histopathological evaluation revealed that 22 cases (95.7%) were successful and one case (4.3%)was fairly successful.
The results of this investigation suggest that the composite resin full crown restoration using Geristore®m ay be considered safe for the pulp and clinically useful.

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Cytotoxic effects of unpolimerized composite resin which was given through the dentin tubules to the human pulp tissue were evaluated in vitro.
Human fibroblast-Like cells(pulp cells) were isolated from extracted primary and permanent tooth pulp. The Bovine permanent tooth was cut into a dentin slice(thickness: 2 mm), and a cavity(diameter: 2 mm, depth: 1.7 m) was prepared in the slice. The cavity was filled with a composite resin (AP-X®), B-2, Kuraray Co. ) which was either light-polymerized or unpolimerized. Pulp cells on which the dentine slice containing composite resin was placed by using the cell-culture insert®(Falcon)were cultured for 24 hours.
The number of surviving cells was counted after Trypan blue staining. In order to determine whether or not apoptosis occured in the cultured cells, fragmented DNA was extracted and electrophoresis was performed using 2% agarose gel. Concentration of IL-1β in the conditioned medium was determined by enzyme-linked immunosorbent assay(ELISA).
The number of surviving cells decreased in both primary and permanent pulp cultures when the dentin slices filled with unpolimerized resin were applied. Polymerized resin had no cytotoxic effect on the cultured cells in the same culture condition. DNA fragmentation was not observed even when the unpolymerized resin affected the viability of the cells. IL-1β, which is often produced by inflamatory tissues, was detected in neither of the resin-treated cell cultures.
These results indicated that unlike polymerized resin, unpolymerized resin components could pass through the dentin tubules and had cytotoxic effects on cultured cells. We conclude that the unpolymerized resin-induced cell death was apoptosis, as revealed null DNA fragmentation, but necrosis.

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Patients who visited the Pedodontic Clinic, Niigata University Dental Hospital for the initial examination in 1980,1988 and 1996 were investigated during the past 17 years to discover the changes in the actual conditions of the patients and fulfill the dental requirements in our community. The following results were obtained;
1. The number of patients who visited our clinic for the initial appointment in 1980,1988 and 1996was 1,079,808 and 526 respectively. It seemed that the decreasing tendency was related to the birthrate in Niigata prefecture.
2. The proportion of patients with chief complaints of dental caries and with severe dental caries has decreased, compared to 1980,1988 and 1996. In contrast, the percentage with malocclusion or tooth abnormality has increased.
3. The number of referral patients from the other dental clinics increased in 1996, and doubled that of 1980.
4. In the case of the primary teeth, the number of treated teeth decreased gradually in staged I C and II A of Hellman's dental age in 1980,1988 and 1996. In stages II C and III A, however, it increased once again in 1996 although it decreased in 1988. In the case of the permanent teeth, the number of treated teeth decreased in stages IIIA and IIIB.
5. The proportion of primary teeth treated with composite resin increased. In contrast, the proportion of the primary teeth treated with metal crowns or resin jacket crowns decreased. In the case of the permanent teeth, the proportion of teeth treated with fisher sealant and composite resin increased.
6. The proportion of patients who visited periodically for more than 3 years to receive oral examination increased in all age group in 1988, compared to the patients in 1980.

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The permeability characteristics of dentin are important factors which influence the transmission of variable stimuli to the pulp. The permeability of dentin is of crucial importance in obtaining good dentin bonding. We have, therefore, investigated to evaluate the potential value of the type I collagen to coat the acid-etched and opened dentinal tubules and to inhibit the permeation of dentinal fluid in vitro study.
The collagen solutions used in this study were prepared by mixing Cellmatrix type I -A®, PBS and 0.08 mM NaOH containing 200 mM HEPES at a final pH 7.4. The bovine dentin surfaces were treated with 10% phosphoric acid for 30 seconds to remove the smear layer and open the dentinal tubules, followed by application of the collagen solution at 37°C for 60 seconds. The microstructures of the dentin surfaces were observed using a scanning electron microscopy (SEM). The permeability of the dentin with or without the collagen application was evaluated under the simulated pulpal pressure of about 25 mmHg. A intrapulpal fluid in this study was reproduced by using 1% bovine serum albumin/PBS, and the value of BSA permeated on the dentin surface was quantified by the Lowly method.
As a result, the following findings were obtained.
1. SEM observation of the dentin surface treated with 10% phosphoric acid followed by the application of 0.3% type I collagen solution at 37°C for 60 seconds showed that the dentinal tubules were covered with a layer of membranous structure. However it was also observed that partially opened dentinal tubules still remained on the treated dentin surface.
2. Under the simulated pulpal pressure of about 25 mmHg, compared with the dentin treated with phosphoric acid only, the permeability of the dentin treated with 10% phosphoric acid followed by collagen solution application was significantly inhibited.
As a result of this basic study, we observed the ability of the collagen application to the dentin surface to seal the dentinal tubules and inhibit the permeation of dentinal fluid.

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The aim of this present study was to measure the occlusal angles of the buccal grooves in the maxillary deciduous and to reveal the difference of the angles between maxillary first deciduous molar and second deciduous molar. Dental casts of the deciduous dentition were obtained from children aged from three years under three years and one month, and caries free, hardly any attrition and with normal occlusion. The occlusal angles of the buccal grooves in the maxillary first deciduous molar and second deciduous molar were measured. The tangents were drawn at the disto-internal oblique plane of the mesiobuccal cusp and the mesio-internal oblique plane of the distobuccal cusp. The occlusal angle of the buccal groove was defined as the interior angle which intersected these tangents.
The results were as follows.
1. The mean occlusal angle of the buccal groove of the one third near the central pit was 128.40°at the maxillary first deciduous molar and was 107.43°at the maxillary second deciduous molar. The mean occlusal angle of the buccal groove of the one third near the buccal margin was 137.44°at the maxillary first deciduous molar and was 107.15° at the maxillary second deciduous molar.
2. The mean occlusal angles of the buccal groove of the maxillary first deciduous molar were larger than that of the maxillary second deciduous molar, and indicated a tendency for the angles to increase from the central pit toward the buccal margin.
3. According to research regarding whether the buccal groove was included in the outline form of cavity on the maxillary deciduous molars, the cases of first deciduous molars which included the buccal groove accounted for 32%, and those excluding the buccal groove accounted for 68%. On the other hand, the buccal groove was included in the outline form of cavity on the second deciduous molars in all the cases.

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This study was carried out investigate the longitudinal relationship of the status of caries from childhood to school age among 655 children. The following results were obtained:
1. The caries prevalence of 65.6% and the average number of decayed and filled teeth (df-t) of 3.80were obtained at 3 years old.
2. The caries prevalence and DF-t at 12 years old was 93.4% and 4.78 teeth.
3. The strong significant correlation between df-t at 3 years old and DF-t in children of school age was shown (p<0.001).
4. There were significant differences in the caries prevalence in children of school age between two groups according to the caries status in children 3 years old (caries free/8<df-t).
5. The more df children there were at 3 years of age the more DF children there were at the school age level.
These results suggest that the status of caries during childhood affects the later status of caries and that's an appropriate dental approach could be useful from early age.

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The prognosis for replantation of traumatically avulsed teeth is decided by the periodontal ligament (PDL) cell condition. In other words, the highest level of PDL cells brings good results without ankylosis or replacement resorption of the root. If the patient cannot obtain the most ideal solution for storage, the tooth must be temporarily placed in a solution that is most readily available and then it has to been carried to a dental clinic. The purpose of this study was to compare the viability of cultured human PDL cells in readily available storage media.
Five solutions including milk, saline, three contact lens solutions for soft contact lens were used as experimental solutions in this study. MEM including 10% FCS was used as the control medium. The PDL cells were cultured from healthy extracted human teeth.
After PDL cells were cultured for 8 days, they were exposed to each solution for 15 minutes at 4r. The MTT assay was measured immediately after exposure and subsequently followed at 1,2,3,5and 7 days after exposure. The morphological changes of the PDL cells were observed immediately and on 7 th day after exposure.
The results were as follows.
1. The growth activity: Milk showed superior activity in the solutions. Saline and three contact lens solutions showed good activity.
They showed, however, lower activity than milk. The activity of each contact lens solution was a different type of activity.
2. The morphological changes: Milk caused healthy cells with spindle-like morphology. In the saline and three contact lens solutions, the cells appeared rounded and shriveled at immediately after exposure, but recovered their original appearance 7 days after exposure.
These results suggest that contact lens solutions are inferior to milk used as first aid when teeth avulse. They are however useful solution as an emergency preservation for short term and in cold storage.

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Follicullar cysts occurr frequetry in the region of the mandibular wisdom teeth, maxilla anterior teeth, mandibular premolar teeth, but they arerare in the maxillary sinus. We report a case of a giant follicullar cyst in the maxillary sinus.
The patient was a 13-years-old girl who visited a dental clinic for dental caries treatment. The pulp of the second molar tooth of upper right was extracted. The tooth was vital, but there was a large amount of pus from the root canals.
After about two months, she visited our hospital due to buccal swelling and trisumus.
We extracted the second molar tooth under clinical diagnosis of the odontogenic maxillary sinusitis, but the oroantral fistula at the extraction cavity did not disappear.
After two months, we performed a cavity close operation, A Caldwell-Luc operation and extracted the impacted wisdom tooth which we had recognised by X-ray examination in the left maxillary sinus using general anesthesia.
At that time, we recognised a gigantic follicullar cyst that filled the left maxillary sinus and encleated it.

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Three comatose patients admitted to the intensive care unit of Chiba Children's Hospital were referred to the division of dentistry for treatment of self-inflicted laceration of the lower lip and the tongue.
Case 1. a 15-year-old boy fell into coma due to diabetic keto-acidosis and had a considerable ulceration in the lower lip, owing to chewing it uncontrollably. In order to improve the uncontrolled jaw movement and the ulceration we used a removable acrylic dental appliance, prepared with coldcuring acrylic resin. The splint was instituted to covere the surface of the hard palate and involved the occlusal surface of the maxillary molars. Furthermore, the additional small amount of resin on the occlusal surfaces of the splint made it possible to obtain 4 mm-open bite between the interincisal space. Relief wax was placed on the dentition of the working model to facilitate removal of the dental appliance, and the space was filled with tissue treatment material (Hydro-Cast®) when the appliance was applied in the patient's mouth. To make sure he avoided swallowing by mistake, a small hole was made in the anterior portion of the appliance, and a suitable length of fine stainless steel wire was attached between the hole and the extra oral fixed place. The appliance was removed 37 days later when the normal muscular activity was restored.
Case 2. a 6-year-old girl with hydrocephalus was affected with severe pneumonia and treated with nasotracheal intubation. Her tongue was edematouly swollen with severe ulcers due to her chewing it during periods of unconsciousness. A removable acrylic dental appliance similar to a bite-block was prepared on one side of the dental arch. After 6 days, the ulcer was mostly cured.
Case 3. a 3-year-old boy who was in schok due to cardiac tanponade was affected by serious edema and ulceration on the tongue. A bite-block-like appliance was used such as in the previous case. After 19 days, the appliance could be removed, because the wound healed with disappearance of the self-mutilation.
These results led to the following conclusions: When a wound occurs in the tongue or lip by selfinflicted behavior in comatose patients, the wound can particularly heal well by using a suitable dental appliance without sacrificial tooth extraction.

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The objective of this investigation was to discover the actual conditions that cause delayed eruption teeth.
The investigation comprised 76 children (40 boys and 36 girls) who complained of delayed eruption of the permanent teeth at the Pediatric Dental Clinic in the Suidobashi Hospital, Tokyo Dental College from April 1989 through June 1995.
Observations were made concerning prevalence of delayed eruption teeth, the causes, the average age of patients at the beginning of treatment, and the treatment itself.
The incidence of the delayed eruption teeth accounted for 7.2% of the new patients. There was no difference according to sex.
The total number of the delayed eruption teeth was 95. The causes of the delayed eruption teeth in the maxilla most often were abnormal position of the tooth germ, followed by an apparent fibrous barrier, supernumerary teeth, retarded exfoliation of the predecessor teeth, effects of dental trauma to deciduous teeth, lack of space for eruption, follicular cysts, odontoma, in that order. In the mandible, the causes were only abnormal position of tooth germ or follicular cysts.
Exposure of the crown from the alveolar bone and active eruptions were more common than exposing of the crown from gingiva.
Three teeth were extracted. The upper central incisor with severe vestibular root angulation was such that it was decided to remove the tooth. The upper central incisor and canine showed odontoma and it was decided to remove the teeth. There were few extractions.

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A 4-year old boy was referred to Osaka University Dental Hospital by his mother with complaints of tongue chewing and buccal mucosa while eating. His face was asymmetrical, and a mandibular shift and anterior crossbite were found. A lingual crossbite from the mandibular first primary molar on the left side to the lateral incisor on the right side was also observed. His mother reported that he had habits of chewing unilaterally and sleeping on the right side of his face. A lateral cephalometric analysis showed that he presented a potential skeletal Class III malocculusion and it could be pr edicted that his mandible would grow excessively as he matures. A frontal cephalometric analysis showed a skeletal crossdite and positional maxillo-mandibular aymmetry. Orthodontic treatment was initiated with the lingual arch soldered with springs. The springs were activated for 6 months and then retained for 6 months. Tooth interference was eliminated by grinding or equibration. His mother was told that he had to stop sleeping on his face. By means of this treatment, the patient was able to r egain a correct bite and showed improvement in his facial asymmetry.

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