Hereditary, environmental and developmental factors play an important role in dentofacial development as well as the initiation of malocclusion disorder. Allergic phenomenon such as asthma that induce an alternative mode of breathing in patients is a contributing factor in malocclusion. Our objective in this study was to evaluate the dentoalveolar morphology in asthmatic children. This study is centered on 44 asthmatic children aged between 6-12 years from J.S.S Hospital, Mysore. Selected variables from model analysis of the casts of the asthmatic group were subjected to comparison with those of the non asthmatic group, which comprised of 44 non asthmatic children. Selected parameters were arch width, arch length and palatal depth. Differences in arch widths, arch lengths and palatal depths between asthmatics and non asthmatics, and between subjects under regular and irregular medication in the asthmatic groups were evaluated by independent sample’s ‘t’ tests. The results obtained revealed that the arch length and palatal depth of asthmatic group had higher values compared to that of non asthmatic groups for both age group (6-8 year old males and females, 10-12 year old males and females). Inter molar width showed a significant lower value in asthmatics in the maxillary arches of 10-12 year old females. Inter incisal width showed a significant lower value in 10-12 year old female asthmatics in the maxillary arch (P < 0.05). The present study proves a strong relation between Asthma and Dentoalveolar morphology as shown by an increased palatal depth and arch widths in Asthmatic children as compared to non asthmatic children.

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BACKGROUND: Systemic disturbance during the fetal and postnatal periods in disabled children may affect the formation and mineralization of deciduous tooth enamel. AIM: To reveal differences in the status of mineralization in the surface and inner layers of deciduous tooth enamel between children with cerebral palsy (CP), those with Down syndrome (DS), and controls. METHODS: Using extracted deciduous teeth obtained from CP children (5 teeth), DS children (5 teeth), and control children (11 teeth), fluoride and magnesium concentrations, used as mineralization parameters, were measured in three regions of the enamel at different depths: the enamel surface (ES), neonatal line (NL), and dentino-enamel junction (DEJ). RESULTS: Fluoride concentration was significantly higher in the ES region than in the NL or DEJ region in all three groups. There was no significant correlation between type of disability and fluoride concentration. Magnesium concentration was significantly higher in the DEJ region than in the NL or ES region. A significant correlation was seen between type of disability and magnesium concentration. CONCLUSIONS: Magnesium concentration was significantly higher in DS children than in control children, suggesting that DS children undergo poorer mineralization. Magnesium concentration tended to be higher in CP children than in control children.

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Early toothlessness in senescence-accelerated prone (SAMP8) mice leads to increased plasma corticosterone levels, learning deficits, neuronal death, and increased astroglial responsiveness in the hippocampus. New cells are generated in the hippocampal dentate gyrus (DG) throughout life in animals as well as humans. Neurogenesis in the hippocampal DG is sensitive to glucocorticoid levels and environmental triggers such as learning. Here we investigated the mechanisms underlying impaired hippocampal function resulting from early masticatory dysfunction, by examining the effects of tooth loss soon after tooth eruption on plasma corticosterone levels, learning ability in the Morris water maze test, and cell proliferation in the hippocampal DG of 1-, 5-, and 9-mo-old SAMP8 mice. Bromodeoxyuridine, a marker of newborn cells, was injected, and BrdU-positive cells were quantitatively analyzed to detect cell proliferation in the hippocampal DG using immunohistochemical techniques. Early toothlessness enhanced the age-related increase in plasma corticosterone levels and learning deficits, and led to a decrease in the number of BrdU-positive cells in the hippocampal DG. Plasma corticosterone levels, learning deficits, and the number of BrdU-positive cells in the hippocampal DG was significantly different between in 5- and 9-mo-old early toothless mice and age-matched control mice, but not between 1-mo-old early toothless mice and controls. These findings suggest that early toothlessness leads to increased plasma corticosterone levels and a decrease in cell proliferation in the hippocampal DG, thereby leading to learning deficits.

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BACKGROUND: Dental caries incidence in early childhood is known to influenced by the behavior of parent with their children, and clinicians and dental staff are advised to provide parents with effective oral health instructions. The objectives of this study were to identify the influence of diet of 18- and 24-month-old children on caries activities and investigate changes related to the behavior of their parents after receiving health instructions regarding caries risk for 2-year-old children. METHODS: The subjects were 1,206 child-parent pairs. The children participated in 18-, 24-, and 42-month-old health examinations at Kurashiki City Public Health Center in Kurashiki City, Japan. Cariostat, a caries activity test (Dentsply-Sankin Co., Tokyo), was conducted and the children were then classified into 6 caries-risk groups based on the 42-month-old predictive cutoff points. Their parents were given oral health instructions on caries prevention by dental hygienists of the Kurashiki City Public Health Center. In addition, a questionnaire regarding diet was given to identify its influence on caries activities in 18- and 24-month-old caries activities in 18- and 24-month-old children, as well as the influence of changes in parenting behavior. RESULTS: A significant number of children in the high-risk group received breast feeding or bottle-feeding with liquids other than water at 18 months of age. Also total time for sucrose-containing food intake was significantly associated with increased caries activity at 18 months of age. After giving oral health instructions to parents of the 18-month-old children dietary habits significantly correlated with the high-risk group at 24 months of age were breast feeding or bottle-feeding with liquid other than water, total intake time of sucrose-containing food, and frequency of sucrose-containing foods intake. Furthermore, parents whose children were in the higher caries-risk group at 18 months of age showed a lower level of change in parenting behavior as compared to those with children in the lower caries-risk group. CONCLUSION: It is important to assess problematic dietary habits in accordance with caries-risk in young children and change parent behavior through effective oral health instructions. CLINICAL IMPLICATION: Clinicians can identify problematic dietary habits in children based on caries-risk and provide effective oral health instructions to parents, which may influence.

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The influence of childhood type II diabetes on bone formation in the growth period was investigated using the mouse mandible, femur, and tibia. Five-week-old mice with spontaneous type II diabetes (KK-A^Y) and C57BL/6J mice as a control group were used. Animals were randomly divided into 3 groups, and the regions were excised after 1, 5, and 13 weeks. Regarding the bone length, growth of the femur and tibia was greater in the KK-A^Y than in the control group, and that of the mandible varied depending on the measurement site. On P-QCT, the trabecular and cortical bone mineral densities of the femur were higher in the KK-A^Y than in the control group, whereas those of the head of the mandible were higher in the control. The thickness and circumferences around the exosteum and endosteum of the cortical bone were significantly different between the KK-A^Y and control groups, and X-SSI, Y-SSI, and Polar-SSI of the femur and head of the mandible, were significantly different. The μCT findings were correlated with the p-QCT findings. Bone morphometry clarified that bone formation of long bone at the early age was more active in the KK-A^Y than in the C57BL/6J group, and bone resorption was promoted with aging in the head of the mandible. These findings suggested that not only the bone length but also bone quality tend to increase in the growth period in childhood type II diabetes.

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Since recent studies have demonstrated that penetration profiles of fluoride into plaque falls from the saliva plaque interface towards the enamel, it was hypothesized that charged components may restrict the inward diffusion of fluoride i.e., protonated fluoride and may penetrate more effectively than fluoride ion. Therefore, in this study, we investigated the effects of pH on fluoride uptake and distribution in natural undisturbed human plaque formed in vivo by means of the Leeds in situ device. At pH 3 significantly less fluoride was present throughout the plaque layer compared with pH 7. Similar profiles were seen in the plaque produced over 1 week and 3 weeks. These results may be due to binding to components of the plaque matrix via hydrogen bonding. Protonation of bacterial cell surfaces may also lead to binding of the ionized portion of fluoride. In conclusion, low pH affected the short-term fluoride uptake from a 1,000 ppm fluoride solution.

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To develop strategies to support feeding and swallowing functions from early stage, we evaluated chief complaints regarding feeding, and assessment of the feeding function. The subjects consisted of 53 preschool children and their guardians, who participated in feeding consultation in a welfare center. In this study, we extracted chief complaints and assessment of the feeding function, and made comparisons. The primary illnesses were intellectual disability (n = 20), autism (n = 16), and Down’s syndrome (n = 17). Chief complaints regarding food selectivity, self-feeding, utensils, and chewing were common, and, particularly, the frequency of chief complaints concerning self-feeding and utensils was significantly higher in the groups with intellectual disability or autism, compared to children with Down’s syndrome. As for evaluation of the feeding function, the proportion of children classified as having a disordered self-feeding function was significantly higher in the groups with intellectual disability and autism (approximately 70%) than children with Down’s syndrome. As a result of comparing chief complains reported by guardians and assessment of the feeding function, in the groups with intellectual disability and autism, many children with chewing as the chief complaint were classified as having a disordered self-feeding function. Regarding children with Down’s syndrome, however, a disordered food-capturing or chewing function was prevalent, even in those with self-feeding as the chief complaint. Thus, children with intellectual disability exhibited many problems regarding chewing, the self-feeding function, and cognitive function. Additionally, inconsistencies between chief complaints and functional evaluation often occurred, suggesting that there is a need for appropriate actions and support.

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Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of tissue non-specific alkaline phosphatase (TNSALP) activity. The disease is caused by mutations in the liver/bone/kidney alkaline phosphatase gene (ALPL) encoding TNSALP. As for dental manifestations, premature loss of deciduous teeth due to disturbed cementum formation is well known. However, few reports of multiple cases have been presented. The oral manifestations of patients diagnosed with hypophosphatasia were analyzed by collecting clinical records of cases from a nationwide survey of pediatric dentistry clinics affiliated with 29 university dental hospitals in Japan. We inquired regarding the number of cases and clinical findings of diagnosed patients. We obtained information for 9 children diagnosed with hypophosphatasia from our university and 10 from 6 other universities. The main oral manifestation was early exfoliation of deciduous teeth, which was found in 15 of the 19 cases. Early exfoliation of mandibular deciduous anterior teeth was recognized in 14, whereas there were no cases of early exfoliation of a permanent tooth. The main oral finding of hypophosphatasia was early exfoliation of deciduous teeth, predominantly in the mandibular anterior region of children aged 1 to 4 years old.

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It is important to understand the level of stress experienced by children during dental treatment, which can be stressful and even lead to permanent dental phobia. We investigated whether chromogranin A (CgA), a stress marker in adults, is useful for determining stress levels in children. Saliva samples were collected before and after treatment from 5 children (3-5 years) who required treatment more than 5 times in a relatively short period. Their parents completed a questionnaire about their child liking/disliking the clinic visit, how they explained to their children the purpose of the dental visit and the type of treatment sought, and to explain descriptively the difference they noticed in their child’s behavior. The CgA levels were significantly higher before than after the treatment in all cases. Pre-treatment CgA values were not always related to dislike for the clinic visit, type of treatment sought, and behavioral reaction to the treatment. The CgA values may have been influenced by the children’s previous experience of the treatment. The results suggest that CgA might be appropriate for verifying children’s stress levels during dental treatment and stress tendency towards dental treatment.

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PURPOSE: The purpose of this study was to examine the internal stress in uncooperative children treated under passive restraint and the changes of it in later treatments under cooperative condition with no need of restraint. We also conducted questionnaire among parents to survey their opinion towards the treatment with restraining device. METHODS: The subjects for electrocardiogram (ECG) recording were the child patients who were referred to the university clinic by the primary care dentists. We recorded ECG of the patients during dental treatment and assessed the autonomic nervous activity as a physiological response to stress. The recordings from uncooperative children were continued at every visit until they became cooperative and no longer restrained. A questionnaire survey was conducted among parents who have experienced the use of the restraining device to their children. RESULTS: Though the sympathetic nerve activity, which elevates with internal stress, and the heart rate were relatively high under restraint in uncooperative children, both diminished in the later session when children became cooperative enough to remove restraint. The questionnaire survey demonstrated that most parents whose children underwent treatment with restraining device showed positive attitudes toward the use of it. CONCLUSIONS: The results of this study suggest that the experience of dental treatment with passive restraint would not necessarily be a traumatic event for children in a short term and parents would accept the necessity through the experience of the treatment in case urgent treatments are required.

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Sotos syndrome is a congenital genetic disorder characterized by overgrowth starting before birth, specific facial manifestations, advanced bone age, and developmental impairment. The characteristics of craniofacial development in Sotos syndrome have yet to be clarified. Eight patients with Sotos syndrome were studied and two types of mutations and a submicroscopic deletion within the NSD1 gene were verified using genetic analysis. Regarding craniofacial growth, the length between the nasion and the sella was longer than the norm as shown by multi-detector row computed tomography cephalometric analysis. The areas of the cranium and maxilla of patients with Sotos syndrome were larger than those of the control group, as measured on cephalometric images. The area of the sella turcica in patients with Sotos syndrome was also larger than that in the controls without significant difference and the morphology of the sella turcica was similar to that of the control. The morphology of the chin in patients with Sotos syndrome showed more protrusion than that in the controls. Early formation of teeth was found in the upper and lower first molars of patients with Sotos syndrome. Eight patients with Sotos syndrome, 6-13 years of age, had craniofacial characteristics of cranium and maxilla overgrowth, but no significant difference was observed in the mandible size between patients with Sotos syndrome and control subjects. No sella turcica bridging or early root formation of the first molars was seen in patients with Sotos syndrome.

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X-linked anhidrotic ectodermal dysplasia (XLHED) is characterized by hypoplasia or absence of hair, teeth and sweat glands. In this study, the authors investigated the ectodysplasin-A1 (EDA1) gene was investigated in a Japanese family in which male member, a child, fulfilled the diagnostic for XLHED. The only affected male fulfils the diagnostic criteria for this disorder. His parents were not consanguineous and both of them were healthy. With informed consent, genomic DNA was isolated from oral buccal epithelial cells from all members of the family. Polymerase chain reaction fragments containing nine exons of the EDA1 gene were amplified. Amplified fragments from both the patient and the parents were directly sequenced. The sequence from the patient revealed a missense mutation (G643A) in exon 5 of the EDA1 gene, which changes codon 215 from glycine to arginine. Heterozygosity was demonstrated in the mother. The present results indicate that amino acid substitution occurs, disrupting the transmembrane domain, and strongly suggest that this was the disease-causing mutation in this family.

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Maxillary impacted mesiodens are frequently encountered in pediatric dentistry. Much research has been conducted concerning their incidence, position, and form. Supernumerary teeth erupting in the primary dentition with maxillary impacted mesiodens are very rare. In January 2011, a nine-year-old boy presented for dental treatment and was found to have supernumerary deciduous teeth. Upon panoramic radiography, multiple impacted mesiodens were found; therefore, computed tomography (CT) was performed for further examination. One month later, the boy was referred to our department for extraction of the deciduous supernumeraries and impacted mesiodens. We suspected that these supernumeraries, mesiodens, and remaining primary teeth would lead to problems with the eruption of the permanent teeth. Therefore, by ascertaining the exact position of the mesiodens and the successional permanent teeth using CT, extraction was performed under general anesthesia in March 2011 without any error. Six months postoperatively, panoramic radiographs showed no superfluous structure that appeared to be a tooth. We suggest that when multiple maxillary impacted mesiodens are found, their exact positions can be located using CT before extraction.

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Multiple supernumerary molars are an uncommon occurrence. In this case report, six molars were observed unilaterally in the maxilla of a 7-year-old patient. An erupted supernumerary molar was found palatal to the permanent upper right first molar. On computed tomogram examination, four unerupted molars were clearly identified distal to the permanent upper right first molar. This dental anomaly is rarely encountered and this may be the first case in which four supernumerary molars were observed in a quadrant with no identifiable pathology.

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