In order to estimate the cleanliness of the air in the operating room of the Pediatric Department of Okayama University Dental School, the relationship between the number of airborn bacteria and the number of persons present in the operating room including the time was estimated using the air sampler method. The following results were obtained.
1. A significant relationship was observed between the number of airborn bacteria and the number of patients (r=0.67, p<0.01, n=233) and persons present in the operating room (r=0.60, p<0.01, n=233 ).
2. The number of airborn bacteria increased after an operation started and reached a high level around 11 o'clock in the morning and decreased at lunch time, but after that time it gradually increased to the maximum around 3 to 4 o'clock in the afternoon. The pattern of the increase of airborn bacteria correlated to the increase of persons present in the operating room.

View full abstract

The present study was conducted to examine whether the radiation thermometer was clinically useable. the subjects were 20 adults,10 females and 10 males. The nasal skin temperature was measured with a radiation thermometer and a thermograph at the same time. The range and coefficient of variation (CV) of the nasal skin temperature were calculated from the raw data as well as the adjusted data. Both the range and CV of the radiation thermometer were compared with those of thermograph. Wilcoxon signed-ranks test was used to examine the differences in the distribution of the range and CV between the radiation thermometer and the thermograph. There were significant differences in the range as well as the CV of the raw data between the radiation thermometer and the thermograph. No significant differences in range as well as CV were found, however, between adjusted data obtained from radiation thermometer and raw data obtained from the thermograph.
These results indicated that adjusted data were more accurate than the raw data from the radiation thermometer. It was also suggested that the radiation thermometer was able to measure the variation of the nasal skin temperature. It was, therefore, concluded that the radiation thermometer could be clinically useful in monitoring patients' emotions as viewed in the previous studies on the thermograph.

View full abstract

This study was conducted to investigate the predictive value of the Cariostat(Rt)e st for approximal caries in primary molars. The subjects were sixty-two children aged 3 to 4 years having sound approximal surfaces on all of the primary molars, who had received regular recall at a pediatric dental clinic. The Cariostat score for the whole mouth, debris index in primary molars and the Cariostat score in approximal surface of primary molars were examined as baseline date. The number of approximal caries in the same primary molars was examined 4 to 6 months later.
The following results were obtained;
1) There was no significant relationship between the Cariostat score for the whole mouth at the baseline and whether approximal caries in primary molars had occurred or not by the second examination. Similarly, the debris index for the primary molars showed no significant relationship at the time of the second examination.
2) The Cariostat score on the approximal surface of the primary molars at the baseline showed a significant relationship with approximal caries in the primary molars at the time of the second examination.
3) Sixty percent of the children whose Cariostat score for the approximal surface was more than 2.0had approximal caries in the primary molars at the time of the second examination. These results suggested that Cariostat of approximal surface had predictive value for approximal caries in. primary molars in the near future.

View full abstract

Previous studies, in which the known Jak (Janus kinase) and STAT (signal transducer and activator of transcription) isoforms were immunohistochemically mapped in developing rat molars, implied that a sizeable list of cytokine superfamily receptor (CSR) /signal-transduction pathway linkages in the cells of the enamel organ involved in the events leading directly to early amelogenesis and dentinogenesis. On the basis of the previous observations it was hypotheseized that the interleukin-6 (IL-6)receptor and the interleukin-10 (IL-10) receptor would be localized in specific sites in the cells of the enamel organ during early amelogenesis and dentinogenesis. To verify this, whole-head, freeze-dried sections were obtained from first molars of 5-day-old rats.
These sections were not demineralized or fixed, reducing the possibility of false-negative results. Because the IL-6 receptor contains IL-6 receptor-α and gp 130, antibodies to the IL-6 receptor-αand gp 130, respectively, and to the IL-10 receptor, were localized using a modification of the avidinbiotincomplexmethod. TheIL-6receptor-α and gp 130 were co-localized in the pre-ameloblasts in the cervical loop, the proximal ends of pre-secretory and secretory ameloblasts, stratum intermedium, differentiating odontoblasts, odontoblasts and in the bone. The IL-10 receptor was localized in the pre -ameloblasts, the proximal ends of pre-secretory and secretory ameloblasts, stratum intermedium, differentiating odontoblasts, odontoblasts and in the bone. These findings indicate that the the IL-6 and IL-10 receptors, and their downstream signal transduction pathway linkages, are upregulated in the cells of the enamel organ and may be involved in the events leading directly to early enamel and dentin formation.

View full abstract

This study is a part of the study on the development of the occlusal function in children that was carried out by the department of pediatric dentistries of six colleges to examine the longitudinal change regarding the occlusal contact for a period of 2 years starting from around the time of the eruption of the first permanent molar. We examined longitudinally the occlusal contact area, the mean pressure, the occlusal power and the maximum power for the first permanent molar and second deciduous molar in 18 cases using data obtained four times every six month from around the time of the eruption of the first permanent molar. There was consequently a positive correlation between the contact area and each other parameter. The occlusion of the first permanent molar demonstrated maturating with fluctuations in each of the four types of contact area during the examination's period. It was in the end suggested that the first permanent molar in every type could be obtained finally a stable situation bilaterally with cooperation of the deciduous second molar. One of the types however did not obtain bilateral harmony of the contact area in cooperation with the deciduous second molar with the final data. It was indicated that this case should be further considered to obtain a conclusion. If further follow-up survey for this research can be succeeded, it will provide a more definite conclusion.

View full abstract

The purpose of this study was to investigate the relationship between orthodontic treatment and temporomandibular dysfunction (TMD). A questionnaire on TMD was carried out with ninety-five patients (22 males and 73 females) who finished orthodontic treatment (multi bracket, chin cap and FKO).
The results were as follows;
1. Twenty-five percent of the orthodontic patients experienced TMD. There was no significant difference in the prevalence of TMD irrespective of the orthodontic method. The prevalence of temporomandibular joint sounds amounted to twenty percent, that of limitation and pain amounted to twelve percent respectively.
2. Sixty percent of the TMD symptoms which occurred after orthodontic treatment disappeared naturally. Of patients who answered the question saying they felt the symptoms of TMD up to then, only twenty-two percent was confirmed through clinical examination.

View full abstract

Changes in the regenerated microvascular pattern and formation of new bone trabeculae during the healing of wounds that result from extraction of deciduous teeth prior to root resorption were observed stereologically using a scanning electron microscope (SEM). The present study, which produced some interesting findings, featured a combination and comparison of observations using a SEM and histological observations using a light microscope.
Seven crab-eating monkeys with deciduous dentition (approx.1 year old) were used in the present study. Specimens for microvascular plastic injection and for light microscopy observations were prepared and observed at 1,3,5,7,14,21 and 42 days after extraction.
Over the first three days after extraction, the blood supply from the tooth germ toward the center of the extraction socket through the pre-existing vascular network was observed in the interface with the permanent tooth germ. The blood supply from the tooth germ gradually decreased over time and an independent vascular network was established in each permanent tooth germ and in the extraction socket 7 days after extraction. Several studies have reported that following extraction, resorption of the bone trabeculae (porosity) was able to be observed in the lower layer of the extraction socket and that the bone trabeculae had become compact in the socket marginal zone. In contrary to this, I did not observe any compact bone covering the socket marginal zone 42 days after extraction. This was possibly a result of the bone structure being altered due to the loss of bite force following tooth extraction. In addition, as the subjects were young and still in the developmental stages this may also reflect the influence of the ongoing growth of the jaws and the eruption of permanent teeth. I, thus, concluded that a difference exists in the healing process of extraction wounds between deciduous and permanent teeth.

View full abstract

Changes in the particle size distribution and morphology of abrasives contained in polishing pastes used for professional mechanical tooth cleaning (P. M. T. C. ) were assessed in vitro in 10 different types of polishing pastes currently available on the market, and the following results were obtained:
1) As PP 3, in which the abrasive is diatomaceous earth, was used for polishing, the tendency for the particles of the abrasive to become smaller was found to be more marked than with the other abrasives.
2) The particles of the abrasive in Prophy Paste RDA 250 and Mel-R also tended to become smaller, but only slightly so in comparison with PP 3.
3) No major changes in particle size distribution were observed in PPI, Prophy Paste RDA 170,120, or 40, NEO-PC, NEO-SC, Mel-R, or Mel-F.
4) The edges of the abrasive in PP 3 were much less sharp than the edges of the abrasives in the other polishing pastes, and the particles in PP 3 tended to appear roundish.
5) There were fewer aggregates of abrasive after polishing with PP 3.
Based on the above results, it is inferred that immediately after the start of polishing, the large aggregates of the diatomaceous earth used as the abrasive in PP 3 effectively eliminated the insoluble deposits that had adhered to the surface of the teeth, that the aggregates gradually disintegrated and particle diameter became smaller, and thus that it is possible to clean teeth without severely injuring the polished surfaces, suggesting that diatomaceous earth is an efficacious abrasive in polishing pastes.

View full abstract

The purpose of this study was to investigate the association between clinical signs and MRI findings in adolescent patients with temporomandibular disorders (TMD). The subjects were 126 patients (20 males and 106 females),8-20 years of age, who visited the Pedodontic Clinic of Kagoshima University, Dental Hospital with a complaint of TMD.
Anterior disk displacement (ADD) was observed in 113 of the 126 patients (89.7%) and joint effusion was observed in 51 of the 126 patients (40.5%).
The prevalence of temporomandibular joint (TMJ) pain was significantly higher (p<0.001) in the ADD-without-reduction group than those in the other groups.
The prevalence of TMJ pain was significantly higher (p<0.001) among patients with joint effusion than that among patients without joint effusion.
The prevalence of the TMJ sound was significantly higher (p<0.001) in the ADD-with-reduction group than those in the normal and ADD-without-reduction groups.
Joint effusion was detected to be significantly higher (p<0.001) in the ADD-without-reduction group than those in the normal and ADD-with-reduction groups. The prevalence of joint effusion in the ADD-with-reduction group was significantly higher (p<0.05) than that in the normal group.

View full abstract

The visual response of children in the dental chair was studied when dental instruments were passed between the female dentist and the dental hygienist. For this purpose, we produced a video showing the dentist and hygienist exchanging a dental mirror and tweezers. The video was individually presented to 40 infant subjects who lay back in the dental chair. The eye movements of the children as they watched were measured for analysis by means of the Visicon Eye-camera. The findings were as follows:
1. The primary fixation point of the eyes was investigated. When the mirror was passed from the hygienist to the dentist,29 children (72.5%) were quick to respond to the motion during the exchange and looked at the dentist and hygienist. Two children (5.0%) looked at their mothers near by first, and nine (22.5%) at other things. In the case of the tweezers,24 children (60.0%) responded to the action and looked at the dentist and hygienist. Three (7.5%) looked at their mothers, and 13 (32.5%)at other objects.
2. While the mirror was being exchanged, the subjects fixed their eyes on the motion itself 428times (87.4%) in all. The number of times their eyes fixed on their mothers and other objects was twice (0.4%) and 60 times (12.2%), respectively. In the case of the exchanging tweezers, the motion drew the children's attention 493 times (88.3%), while mothers and other objects,11 times (1.9%)and 55 times (9.8%), respectively.
3. Regarding the pattern of the scanning movements of the eyes,33 child subjects (82.5%) watched only the delivery of the mirror, four (10.0%) ran their eyes over the motion itself and their mothers, and three (7.5%) gazed around at other objects. In the case of the tweezers,29 subjects (72.5%)turned their eyes to the delivery action only, three (7.5%) to their mothers, seven (17.5%) to the action and their mothers, and one (2.5%) to other objects.
4. Of the 40 subjects,37 (92.5%) showed a reaction to the delivery of the mirror. Of this figure,83.8% reacted upon hearing the dentist say “Mirror, please” to the hygienist. In the case of the tweezers,39 children (97.5%) reacted, of which 71.8% reacted to the dentist's voice saying "Tweezers, please.
"From the above, we concluded that children are very sensitive to the movement of the female dentist and the dental hygienist as dental instruments are being passed.

View full abstract

Experiments were conducted to examine the spatial perception of children patients under treatment in response to the movements of their mothers. For this purpose, a video was produced on the assumption that a child lying on its back in the dental chair would respond when his or her mother moves in to look into his or her face. The video was shown to a total of 37 child patients. Using the Visicon camera, we measured and analyzed the ocular movements. Our findings were as follows:
1. Thirty-one children (83.8%) scanned their mothers (scanning group), while six children did not (non-scanning group).
2. In the scanning group, there were 25 child subjects (80.6%) who also cast their eyes over objects other than their mothers. The average number of times their eyes fell on their mother was 17.9 and the average length of time their eyes rested on their mothers was 2,980.6 ms. Likewise, the number of times and the length of time their eyes fell and rested on other objects were 6.2 and 918.6 ms respectively.
3. For 28 subjects (90.3%) the primary fixation point of observation was recorded when their mothers tried to look into the children's faces. On the other hand, three subjects (9.7%) fixed their eyes on their mothers for the first time when their mothers were looking into their faces.
4. There were six kinds of scanning pattern in the scanning group and three kinds in the nonscanning group.
Upon analysis, we concluded that child patients in the dental chair are quick to respond to their mothers' movements and at this stage, they turn their eyes to their mothers.

View full abstract

It is supposed that the internal structure of the maxilla of children undergoes remarkable changes with the growing of the bone and the exchanging of teeth. The aim of this study was to analyze morphometrically the structural changes of the trabecular and cortical bones at the central and lateral incisor regions of the maxilla during development. Forty-two maxillary bones taken from Indian children were used. They were divided into six groups according to the stage of tooth eruption, namely, one at the stage of deciduous dentition and five at the stages of mixed dentition. Each sample was embedded in polyester resin and then cut labio-lingually into serial sections with thickness of 500 μm. Two sections with the center region of the central and lateral-incisor were chosen from the serial sections for taking soft X-rays. These images were inputted into a direct image analyzer using a TV camera for analysis of the trabecular bone density and width, specific length, the direction ratio and cortical bone width. Trabecular bone density, width and specific length in each region decreased before the eruption of posterior permanent teeth and increases after the eruption. The orientation of trabecular bone was consistent with the one of root axis of central incisor. It was suggested that the orientation of trabecular bones was changing against the different directions of the occlusal force in the period from the missing of deciduous teeth to the eruption of permanent teeth.

View full abstract

The purpose of this study was to evaluate the changes of the dental arch from the pre-dental to the primary dentition.
Materials were 52 longitudinal dental casts taken from 22 boys and 30 girls. Dental arch length, anterior dental arch length, posterior dental arch length were measured at each dental stages using 3dimesional digitizer, while dental arch width were measured as the distance between left and right canines, first and second molars etc.
The results were as follows;
1) Dental arch length showed gradually increased in the maxilla, while there was remarkable increase in the mandible after beginning of the eruption of the deciduous canines.
2) Inter canine width increased at the eruption of the deciduous canine in the maxilla, however it decreased at the eruption of the deciduous first molar in the mandible.
3) The differences were observed in the growth timing of anterior and posterior part of the dental arch length and most posterior part of the dental arch width between boys and girls
4) The advanced growth took place in posterior section of the dental arch, and then the dental arch width showed tendency to increase of the eruption of the deciduous canine.

View full abstract

[in Japanese]

View full abstract

The purpose of this study was to investigate occlusal contact relationships during lateral excursions in the primary dentition.
A custom computer system combining lower jaw movement and three-dimensional tooth shape to display tooth contacts during mandibular movements. Lower jaw movement along all 6 degrees of freedom was measured with an opto-electronic movement analysis system at a sampling frequency of 100 Hz. Tooth shape was measured using a three-dimensional digitizer at 0.2 mm intervals. These two sets of measurements were then converted to the same coordinate system in order to establish the three-dimensional relationship between upper and lower occlusal surfaces at any mandibular position. At every mandibular position, the distance between the upper and lower occlusal tables was calculated. Distances of less than 0.2 mm were defined as an area of occlusal contact.
Occlusal contact areas of 5 children (3 boys and 2 girls, with a mean age of 5 year-7 month) were analyzed during lateral excursion using this system. None of the subjects had dental caries. The normal primary occlusion of the children was under continuous oral management in our department.
The results of this preliminary study are as follows:
1. Computer graphics can be used to visually display changing occlusal contact area during lateral excursions in the primary dentition.
2. The occlusal contact area of every tooth can be quantified during lateral excursions in the primary dentition using this system.
3. Our preliminary results indicate that occlusal contact occurs at the primary deciduous second molars on both the working and non-working sides during lateral excursion.
4. Further studies are needed to determine the functional role of these occlusal contacts in the primary dentition.

View full abstract

We examined the caries incidence of 349 children who undergo periodical oral check ups at five pediatric dental clinics. The subjects were divided into two groups on the basis of the definition of the high-caries groups which was enacted by the Health Insurance Bureau, the Ministry of Health and Welfare in 1994. The groups were classified further according to the time when the oral hygienical checking had started. The caries incidence of the classified groups was compared longitudinally and it was shown that the early start of oral hygienic control before the eruption of the first permanent tooth was effective in inhibiting the caries development of the permanent teeth. This result suggests that the early caries check ups during the primary dentition period is important for prevention of dental caries.

View full abstract

Instead of the distal shoe appliance, we used the M type loop appliance to maintain the space of a mandibular second primary molar that had been lost before the eruption of the permanent first molar, on the most part in many cases it was recognized that the permanent first molar was able to be induced to an appropriate position.
Later, in the cases in which the M typeloop appliances were used, we observed how the un-erupted mandibular first permanent molar drift within the alveolar bone and gingiva with premature loss of the second primary molar until the first permanent molar erupted, and obtained the next following results.
1. Of the 40 cases in which the prognoses were able to make an identification,34 cases showed that the permanent first molar erupted along the M type loop appliance, and 6 cases showed that it erupted more mesially than the M type loop appliance.
2. In the cases in which the permanent first molar erupted along the M type loop appliance, using 15cases' study casts we were able to measure the distal edge of the pre-extraction second primary molar. In these cases, then, the position of the medial edge of the erupted permanent first molar was compared with the position of the distal edge of the pre-extraction second primary molar. As a result, the medial edge of the permanent first molar was found to be positioned medially at an average of 1.41 mm from the pre-extraction second primary molar distal edge.
3. As the positions of the M type loops were identified by using the Oblique Cephalogram, most of the under points of the loops were set up in the position that approximated the neighborhood of most of the under depressions of the opposite side second primary molar's distal side.
4. We observed that an un-erupted permanent first molar drifted within the alveolar bone and gingiva with premature loss of the second primary molar not only medially but also variously.
5. It was thought that the reason the permanent first molar erupted more medially than M type loop was that the setting of the M type loop was inadequate.
The results of this investigation suggest that if the setting of the loop is carried out prudently and the progress observation is carried out properly, the M type loop can be administered as a space maintainer with premature loss of the second primary molar.

View full abstract

This study was conducted to investigate the relationship between the caries activity test (CARIOSTAT®) and status of dental caries. The subjects were 1671 children aged from one year to fifteen in Okayama. The findings were as follows:
1) Significant positive correlations were obtained between the Cariostat scores and the caries scores (df, df+ DF, DF) in each age group except the 1 year and 9 year old group.
2) The children with the Cariostat score of 2.0 or higher showed more severe mean caries score than the children with the Cariostat score of 1.5 or lower in each age group except the 1 year,2 year,9 year and 10 year old group.
These results suggested that the Cariostat score reflected the status of caries in many age groups from infants to school children, and that the Cariostat score of 1.5 could be effective as a cutting point for the screening of dental caries.

View full abstract

The purpose of this study was to investigate how acute nasal obstruction affects the relationship between mastication and respiration.
Methods: The subjects were 9 healthy adults. Electromyograms (EMG) were obtained from the masseter muscle using a surface electrode technique and respiratory curves were obtained with a mechano-electrical transducer for the respiration. The EMG and respiratory curve were recorded simultaneously. The effects of nasal obstruction on masticatory and respiratory cycles were examined at rest, and during mastication of gum (2 g) and peanuts (3 g). The condition of nasal obstruction was simulated by pinching the nose.
Results: 1. At rest, there were no significant differences in the respiratory cycle time between the normal condition and the condition of nasal obstruction. The respiratory rate and relative tidal volume under the condition of nasal obstruction significantly decreased in comparison.2. In the condition of nasal obstruction, both the masticatory cycle time and respiratory cycle time during mastication of gum and peanuts were prolonged compared to those of the normal condition. Respiration was slow, shallow and irregular in the condition of nasal obstructions.
Conclusions: These results, indicated that nasal obstruction affects not only mastication but also respiration. Moreover, the relationship between masticatory and respiratory cycles changes in the nasal obstructed condition.

View full abstract

Amelogenesis imperfecta is a group of diseases which harm the primary formation process of enamel development during tooth embryogenesis by a factor peculiar to inheritance.
This time we experienced a patient who was diagnosed as having amelogenesis imperfecta based on the results of clinical examination, pedigree analysis, histopathological examination and electron probe X-ray microanalysis. The details are as follows:
1) Hypoplasia of the enamel of all of the primary teeth and all of the central incisors and the first molars was seen.
2) The panorama and dental X-ray analysis indicates that the thickness of the enamel of the patient's teeth is very much thinner than that of normal deciduous teeth.
3) Histopathological examinations, and X-ray microradiogram and X-ray microanalyzer analysis using the finishing samples confirmed that this case belongs to amelogenesis imperfecta (hypoplasia of the enamel)
4) The results of the above and the pedigree analysis indicates that this case belongs to amelogenesis imperfecta, type a-3) on the basis of Witkop and Rao's classification. From the pedodontics standpoint, the necessary treatment and observation during growth and development have been continued.

View full abstract

Three cases of impalement injuries to the palate in children are described.
The first case; a 26-month-old boy was referred to the Division of Dentistry of Chiba Children's Hospital, due to oral hemorrhaging after he fell to the floor with a toy pipe in his mouth. A bleeding,25*35 mm laceration was seen in the mucosa of the hard palate. The wound needed over 10 stitches to close, with 4-0 VICRYL® under local anesthesia. The suture stitches were removed without any trouble after 17 days.
The second case; a 35-month-old boy fell down with a wooden chop stick in his mouth. The tip of the stick penetrated his soft palate into the nasal cavity. The stick was easily pulled out, and the palatal wound was sutured under local anesthesia. After 6 days, the 4-0 VICRYL® sutures were removed.
The third case; a 1-year-old boy was referred to us because of oral bleeding. He fell down while having the spout of a watering pot in his mouth. A semicircular-shaped wound of his soft palate with a diameter of 15 mm was found. The wound communicated with the nasal cavity. It was also possible to close this wound with sutures (4-0 VICRYL®) under local anesthesia.
For infants or children, under local infiltration anesthesia, the sutures of wounds in the oral cavity are very difficult to treat due to involuntary movement of the whole body and the tongue. It occasionally occurs to them to involve unexpected injuries or breakage or swallowing of the needle. However, the use of local anesthesia with appropriately surgical procedures could be recommended because the general anesthesia in infant or children has several disadvantages.

View full abstract

Oral management of two sisters out of three who were affected amelogenesis imperfecta with dentin dysplasia for 12 years.
At the time of the first visit, the elder sister was 7 years,2 months old and the younger sister was 2 years,5 months old. The chief complaint was the abnormal shape of their tooth crowns. No abnormality was discovered in their general physical status. All of the teeth of their father had been affected with hypoplasia and he had been wearing full dentures both on the maxilla and mandible.
At the first oral examination for the elder sister,13 primary and 8 permanent teeth had erupted and the teeth showed yellow discoloration. The tooth crowns of the 8 primary teeth and one mandibular first molar were severely destroyed and not be able to restored. At the first oral examination of the younger sister, all of the primary teeth had erupted and the dentin of all of the teeth were exposed, with yellow-brown discoloration being observed. The exposed dentin surfaces were smooth. The permanent enamel was thin, rough but hard and showed hypoplasia. Spacing between the teeth and attrition were also observed. Both for their primary and permanent teeth, with increase in age a highly narrowing or closing of the pulp chamber was obseved on the x-ray films. Closed pulp chambers were especially obvious for the permanent teeth of the younger sister. With histo-pathologic observation of the primary teeth, small number of dentinal tubles and irregularity of the dentin calcification were evident and dentin dysplasia was diagnosed.
Soon after the eruption of the teeth, all of the teeth were first restored with glass ionomer cement, and then the teeth were restorative with adhesive composite resin. Finally, all of the primary incisors were restored with restorative composite resin crowns and all of the primary canines and primary molars were restored with steel crowns. All of the permanent incisors were first restored with restorative composite resin crowns and finally restored with prosthetic composite crowns. All of the permanent molars and premolars were first restored with steel crowns and finally restored with metal full cast crowns. The adhesiveness of the restorative materials such as the bonding resins and glass ionomer cements to the enamel and dentin was low, and the peeled off with loss of the restoration often occuring.
With cephalometric analysis of the elder sister at 18 years 9 months of age and the younger sister at 14 years 6 months of age, no disorder was obtained except for the shallow over bite of the younger sister.
These cases might be classified into autosomal dominant amelogenesis imperfecta combined with dentin dysplasia.

View full abstract

Three dimensional imaging has been used with ease due to the spread of three-dimensional computed tomography (3 D-CT). It was difficult to image three dimensional constructions using conventional X-rays, but,3 D-CT has made it possible to observe the entire display in detail on a plane. As a result,3 D-CT is useful for the preoperative diagnosing and planning in the oral and maxillofacial region. We report that 3 D-CT was useful for extraction of multiple impacted supernumerary teeth in a patient with cleidocranial dysostosis.
The patient was a 12-year-old boy who had undergone dental treatment in our hospital since he was 3 years old. We diagnosed that it was necessary to extract multiple impacted supernumerary teeth, and therefore, we applied 3 D-CT clinically.
Using this method, we were easily able to observe the three dimensional position and shape of the impacted teeth.

View full abstract