We examined the relationship between serum glucose value and caries incidence in 88 children (61 boys and 27 girls) in the deciduous dentition period with an average age of 3 years and 11 months (2 to 6 years old), and reached the following conclusions.

1. While the group who had a “decayed teeth rate” (number of untreated carious teeth/(number of erupted teeth+ number of missing teeth) × 100%) of 50% or lower had an average serum glucose value of 101.5 mg/dL, the average serum glucose value of the group whose decayed teeth rate exceeded 50% was higher at 110.4 mg/dL. However, we did not observe a significant difference between the two groups.

2. While the average serum glucose value for the group with zero C3 teeth was 92.8 mg/dL, the average serum glucose value for the group with one to four C3 teeth was 108.0 mg/dL, which was significantly higher than the former (p ＜ 0.05 : t-test). The average serum glucose value for the group with five or more C3 teeth was 112.5 mg/dL, which was even more significantly higher than the group with zero C3 teeth (p ＜ 0.01 : t-test).

Based on these results, the serum glucose values of children with severe caries tended to be higher than those of children with mild caries, indicating the possibility that severe caries is associated with carbohydrate metabolism.

Nitrous oxide inhalation sedation is used in many medical institutions in developed countries for its sedative and analgesic effects. However, in pediatric dentistry and dentistry for persons with disability, where many patients have difficulty coping with dental treatment, it may be necessary to change to other means of behavior management because inhalation sedation has not been proved effective for all patients.

Therefore, in this study, we investigated the association of patientsʼ state and behavior management to examine the appropriate choice of inhalation sedation.

In our hospital, the use of inhalation sedation increases with age, and is used most in the order of surgical treatment (47%), endodontic treatment (44%), restoration treatment (38%), and prosthetic treatment (36%), but only for 11% in preventive treatment. Among infants, inhalation sedation is used most for dental phobia, significantly larger than its use for patients with autistic spectrum disorder, mental disease concurrence, and cerebral palsy.

Based on the foregoing, nitrous oxide inhalation sedation is not useful for all states of patients and treatment regimens, but is considered useful for behavior management when chosen appropriately.

We investigated how the parents of pediatric dental patients collect medical and health information. With regard to whether or not parents get information about their children's health by using the internet, more than 90% of the respondents answered, “I often use it”, or “I sometimes use it”. Regarding the questions “Was the problem was solved?” and “Was the information reliable?”, more than half of the respondents answered, “Not really”. Regarding the questions on whether they use the internet for researching the oral health of their children, about 60% of them answered “I have used it before”. The internet was often used in cases of sudden and urgent matters such as trauma. It was found that the respondents did not receive paper media such as leaflets related to health, and even if they did, only a few people read them, which showed that they did not actively get information from paper media. When collecting medical and health information, parents may be concerned about whether or not the information is applicable to their child's situation. Thus, it is clearly important for medical practitioners to provide sufficient explanations on the child's situation in daily clinical practice.

We investigated new preschool patients with the chief complaint of dental caries at the Department of Pediatric Dentistry of Hiroshima University Hospital during the fiscal years of 2008, 2013 and 2018. The ratio of preschool patients with the chief complaint of dental caries to new patients has increased : the largest percentage being 3 years old in 2008, but 5 years old in 2013 and 2018. Among the patients with dental caries in 2013 and 2018, there were higher rates in the primary upper incisors than in 2008. We classified the patients with dental cavities : class I was the largest group in 2008, but class III was the largest group in 2013 and 2018. This shows that the severity of cavities worsened from 2013 to 2018. The number of patients from distant locations has increased. Most of the referrals came from private clinics in every fiscal year and the proportion has also increased.

In daily pediatric dentistry, parents regularly consult for an assessment of the oral health of their infants. However, awareness of infant oral health is rarely discussed by the pediatric dentist and the newborn's mother.

To eliminate the mother's worries about child care and the oral health of her children, and to provide support for child-rearing, we investigated the current concerns of mothers regarding the oral health of their infants, among mothers who had taken a baby dentistry class at our university hospital. The following results were obtained from a questionnaire survey conducted in 2016 and 2017.

1. The highest percentage of mothers who attended the baby dentistry class were 35 to 39 years old (33.8%), with mothers aged 35 and over accounting for more than half of all mothers. The majority of the children were first-born (87.1%), while 38.1% were 6 months old. The sex distribution of the children was approximately equal.

2. The consultation rate for pregnant women's dental checkup was 99.3% and most of them were taken to our university hospital.

3. The common concerns that mothers had were about baby food.

4. The most common concerns of the mothers about their infants' oral health were dental caries.

Pediatric dentists not only provide dental caries treatment and help prevent them in children, but also give consultation and advice to mothers regarding oral growth and development to improve their children's oral health. Thus, we should try to help alleviate caregivers' anxiety about childcare and help support childcare.

Dietary problems are a significant concern for parents of both children with typical developmental disorders and children with autism spectrum disorder (ASD). Although it is presumed that children with ASD have different dietary problems from children with typical development, there are few studies comparing the two. Therefore, we conducted this study to compare the dietary needs of children with ASD and those of nursery school children in order to help support the dietary needs of children with ASD.

The subjects were 42 nursery school children and 58 children with ASD. A questionnaire about oral functioning and eating was administered to the children, and the mealtime situation was also evaluated. The results of the questionnaire showed that the parents of the nursery school children selected many items related to motivation, while the parents of the ASD children selected many items related to oral function as well as picky eating. Regarding the function of feeding and swallowing, there were few problems among the nursery school children, and the way they ate and manipulated the eating utensils improved as they got older. On the other hand, in children with ASD, “inability to take in food with the upper lip” and “inability to bite with the anterior teeth” were prominent, which was thought to be related to sensory deviation. In addition, the immaturity of food manipulation may have affected the way they ate. In supporting the eating habits of children with ASD, it is important to understand the characteristics of the disease and to improve the environment in which the child is treated.

Abused children are prone to many dental problems such as a high caries risk, untreated dental caries, and poor oral hygiene, in addition to dental trauma. We conducted a survey of 1,344 children who first visited the Department of Pediatric Dentistry of Tsurumi University Dental Hospital between June 2014 and July 2015. The subjects of this study were 187 children who had the caries-attack-pattern-C2 following the guidelines of dental health checkups for 3-year-old children established by the Ministry of Health, Labour and Welfare (MHLW) of Japan, and/or diagnosed by attending pediatric dentists, dental hygienists, and staff with suspicion of abuse. The children speculated to have been abused were carefully examined by pediatric dentists, dental hygienists, and staff by filling out a child abuse assessment sheet.

The results of the assessment sheets were examined. The pediatric dentists reached an agreement based on the consensus of their finding and also by referring to the flowchart for judging child abuse. As a result, eight of the 187 were suspected to have been abused. We then compared these eight children with the other 179 children who were considered not to have been abused.

1.The major characteristics of both groups were dental caries, and the incidence of pattern-C2 was the highest.

2. In the group suspected to have been abused, the percentage of children whose guardians were receiving government financial assistance was high. Also, the dft+DMFT index of these children was higher than that of national average indices.

3.Regarding the characteristics of the children suspected to have been abused, unsanitary practices accounted for 75% of the children. Fifty percent of guardians failed to seek dental treatment for children with dental caries even long ( ≥ one month) after the onset.

In pediatric dental clinics, pediatric dentists and dental hygienists have close contact with children over a certain period of time during the treatment. Hence, they may notice signs of abuse and prevent neglect by parents.

This study examined the oral functional status of children to establish parameters for the early detection of mouth breathing habits based on simple daily life assessment. A questionnaire survey was conducted among 355 guardians of children aged 3 to 6 years old attending a daycare center and a kindergarten in Yokohama City.

Responses to four survey questions on whether “they keep their mouth open during the daytime,” “sleep with their mouth open,” “nasal congestion during the daytime” and “nasal congestion while sleeping” yielded six characteristics of mouth breathing categories. Based on the answers, the children were divided into two groups, mouth breathing and nasal breathing groups, and were further asked a total of 66 questions. Comparison between the two groups revealed significant differences in seven statements in response to all six characteristics of which five questions, except the two questions used to define mouth breathing “keep their mouth open during the daytime” and “sleep with their mouth open,” are as follows :

1.Often touches the nostrils

2.Trouble hearing

3.Frequent dry mouth

4.Flaccid lips

5.Drops food while eating

These characteristics are considered to be five new signs for the early detection of mouth breathing habits. Recognition of these signs by child caretakers, kindergarten teachers, and guardians in the initial stage could lead to early detection and timely management of mouth breathing habits.

We surveyed 41 pediatric patients receiving perioperative oral management in a childhood cancer hospital to clarify the oral conditions of childhood cancer patients. The following results were obtained.

1.The number of pediatric patients was 41 (female : 22, male : 19) from 2016 to 2019. The most common diagnosis was acute lymphatic leukemia (20 patients).

2.Oral mucositis was the most frequent oral complication in pediatric patients with cancer undergoing chemotherapy, radiation therapy, and hematopoietic stem cell transplantation. In addition, we observed caries, eruption gingivitis, xerostomia, and so on.

3.The most frequent oral complications occurred in Hellman's dental age IIIB (11 events). These oral complications included oral mucositis, caries, and eruption gingivitis. We consider that the type of oral complication changes depending on the growth and development of pediatric patients.

4.It is important to continue providing oral health care during perioperative oral management keeping in mind the child's growth and development.

The environment surrounding children and disabled persons changes with the times. In recent years, the declining birthrate and increasing number of dual-income households are pronounced. In addition, the environment surrounding our clinic has changed due to its relocation. To grasp the current role of our clinic in Hokkaido, we surveyed the state of new patients over the past six years.

The number of new patients and the percentage of introduced patients have showed an increasing tendency. The most common patient age at the first visit was three years old, and caries treatment was the most common chief complaint. Most of the new patients lived in Sapporo, but a few lived in remote areas. Patients with a systemic disease or disorder accounted for 35.9% of the total. The percentage using behavior management in treatment accounted for 62.4%. Approximately half of the patients continued regular clinic visits after treatment. These results suggest that our clinic is widely recognized as a higher order medical institution, implying that we should strive to strengthen coordination among areas in Hokkaido.

In this study, we investigated the trends in pediatric patients on their first visit to a general dental clinic. A comparison of patient groups during 5 years both before and after a pediatric dental specialist came to work in our clinic (early and late groups) led to the following conclusions.

1. The total number of pediatric patients on the first visit was 1,845, which represented 27.6% of the total number of patients on the first visit; the monthly average number of pediatric patients on the first visit was 15.1.

2. Patients under the age of six represented 73.0% of all the pediatric patients on their first visit throughout the entire period, with the percentage being higher in the late group.

3. More than 70% of the patients visited from neighboring towns within 2 km from our clinic.

4.The majority of them were motivated to visit us after passing by our clinic or looking at a signboard, followed by after visiting our website or referrals by acquaintances.

5. The most common reason of visit was the desire to receive dental examination (42.8%), followed by caries-related complaints, prevention-related ones, dentition-related ones, recommendation of consultation, and trauma in this order. Caries-related complaints were the most common in the early group, while the desire for dental examination and prevention-related complaints were higher in the late group and more common than caries-related ones.

6. The number of teeth with caries at the first examination was 0 in 55.1% of the patients during the entire period, and the average number of caries per individual was smaller in the late group. The average number of visits for the first treatment per individual was higher in the late group.

7. 82.2% of patients did not discontinue the treatment received at the first consultation, while 17.8% discontinued it. The number of patients without discontinuation was higher in the late group.

8. Approximately one-fourth of the patients visited our clinic regularly after treatments. The number of patients who regularly visited our clinic was higher in the late group.

These results suggest that pediatric dentistry is important even in general dental clinics and that the presence of pediatric dental specialists improves the quality of practice.

There have been reports of tick bites in the maxillofacial region, but no reports in the oral cavity. Here we report a case of a tick bite on the palate. The patient was a boy aged 1 year and 0 months. An elastic hard tumor with a smooth surface, black partly brown mottled pattern, and well-defined border was observed at the center of the right side of the palate. On the evening of the first visit to our clinic, he exhibited a fever ranging from 39.1 to 39.6℃ and exanthema on the buttocks, palms and soles. A nearby pediatrician diagnosed it as hand, foot and mouth disease and prescribed cephem antibiotics to prevent secondary infection. Six days later, the fever temporarily subsided. Two days later, the fever recurred and exanthema was observed. Then, his fever subsided suddenly. Ten days after the first visit to our department, the tumor disappeared, and several 1- to 2-mm indentations were found at the site where the tumor was located, and there were bullae around it. Three months later, the bullae disappeared. Nine months later, the patient made steady progress.

There are many infectious diseases transmitted by ticks which may become fatal if they become severe. Tick bites rarely occur inside the mouth, but this can happen at an early age when very young children tend to put anything into their mouths.

Nodular fasciitis is a benign tumor that can be difficult to distinguish from malignant tumors. Nodular fasciitis usually arises in the subcutaneous fascia of the extremities and trunk but rarely occurs in the oral cavity. In this report, we describe a case of nodular fasciitis arising in the alveolar mucosa of a 4-year-old girl. Symptoms of local malocclusion, due to abnormal mobility and irregular inclination of the upper-right primary incisors, had rapidly worsened during the previous month. The roots of those incisors and surrounding alveolar bone in the lesion showed absorption in X-ray images, but cone-beam computed tomography (CBCT) images revealed the lesion to have a smooth margin. The tooth germ of the affected permanent incisors was also inclined. We suspected the lesion to be a tumor based on the clinical features. We performed an incisional biopsy, and nodular fasciitis was diagnosed according to the immunohistochemistry and histopathology findings. The tumor has not recurred postoperatively during a 7-year follow-up. To our knowledge, this is the first report of nodular fasciitis occurring in the alveolar mucosa with bone absorption of a young child. In addition to describing this unique case, we review the literature regarding the diagnosis and management of nodular fasciitis.

Hypercementosis is a non-neoplastic lesion that frequently occurs in the molar teeth, and is a rare disease even among radiopaque lesions that occur in the jaw bone. We report a case of eruption disorder due to hypercementosis around the cervical central incisor adjacent to the cleft fissure of a patient with cleft lip and alveolus.

The patient was an 11-year-old boy. We received a request from an orthodontist for detailed inspection due to delayed eruption of the upper left central incisor. On dental CT scans, we identified opaque layers with unclear margins following the cervical upper left central incisor, and the patient was diagnosed with hard tissue. We decided that the hard tissue would need to be cut out to improve the eruption and torsion of the upper left central incisor. Therefore, we cut out the hard tissue under general anesthesia when the patient was 11 years and 6 months old. Eruption of the upper left central incisor was observed one month after the treatment, and there was improvement in the torsion by 12 years and 2 months of age.

As there have been no reports about hypercementosis of the anterior maxilla, it is suggested that the present case took place based on a different mechanism of onset compared with other cases reported previously.

Hereditary fibromatosis of the gingiva is a rare disease that is mainly inherited in an autosomal dominant manner. Fibromatosis of the gingiva in children has been reported to develop during puberty, while cases in infancy are quite rare. We experienced a case of hereditary fibromatosis of the gingiva in a twomonth-old girl that had been initially noted at the time of birth.

Gingiva color was normal and no inflammatory symptoms were noted. A walnut-shaped palatine ridge 5×10 mm in size was seen on the palate. Because of gingival hypertrophy, an intermaxillary space during occlusion was not detected. Follow-up was determined to be the best treatment plan for this case, as (1) no deciduous tooth had yet erupted, (2) height and weight were normal, though feeding required an extended amount of time, and (3) unnecessary surgical invasion should not be performed for a child aged two months. Nevertheless, we also were prepared to perform a gingivectomy should some problems occur, such as delayed eruption of a tooth, a functional disorder, or rapid growth of fibromatosis.

Follow-up examinations showed that all deciduous teeth erupted at normal times and gingival hyperplasia regressed with tooth eruption. It is considered that periodic observation is the best option for hereditary gingival fibromatosis in infantile cases with deciduous dentition in an unerupted stage, with a plan for surgical treatment for specific problems that may develop.

Aerophagia is defined as a disease that causes chronic belching, nausea, and abdominal distention due to excessive air swallowing. The patient was a 10-year-old boy who complained of chronic abdominal distention and pain by aerophagia. The abdominal symptoms had worsened after fundoplication surgery. A nasogastric tube was placed to release the gas accumulated in the stomach. Frequent abnormal swallowing and tongue thrust were observed at the first visit to our clinic. Upon swallowing, his tongue protruded between the front teeth, and his orbicularis and mentalis muscles showed a dysfunctional pattern. We diagnosed abdominal distention and pain by aerophagia due to orofacial myofunctional disorders. Therefore, oral myofunctional therapy (MFT) was used to address these problems and to correct the improper function of the tongue and orofacial muscles. MFT improved the function of his orofacial muscles and this improvement led to a reduction of abnormal air swallowing. Five months later, the nasogastric tube was removed. In addition, his occlusal condition had also improved. MFT may be a useful technique for alleviating aerophagia due to orofacial myofunctional disorders.

The causes of premature loss of deciduous teeth have been reported to be associated with caries, periodontal disease, trauma, occlusal trauma, bruxism, and systemic diseases. However, in daily clinical practice, there are rare cases in which it is difficult to identify the cause of premature loss. Here, we report a case of premature loss of a deciduous canine in a 4-year and 6-month-old boy.

The patient was referred to our clinic with premature loss of the mandibular left deciduous canine. As the intraoral findings, the mandibular left deciduous canine tooth had fallen out, and the dropout cavity was observed. He had tooth attrition caused by bruxism, but no dental history of caries or trauma was noted. To begin with, a blood test was performed for screening of systemic diseases. In addition, bacteriological examination was performed to evaluate the association with periodontopathic bacteria. However, there were no abnormal findings in those examinations. Next, we carefully observed the fallenout tooth. Although there was no abnormal appearance on visual inspection, fracture lines with a crack degree were found under stereoscopic microscope observation. Furthermore, CT examination revealed that the fracture continued from the crown surface to the pulp cavity. Finally, excessive physical irritation caused by bruxism had resulted in crown fracture, which might induce pulp necrosis and apical periodontitis. Furthermore, excessive occlusal pressure due to the bruxism and lateral movement would affect this condition. Because primary teeth have less mature calcification than permanent teeth and due to their structural characteristics, tooth microcracks often occur. Furthermore, excessive occlusal force applied to the tooth due to trauma or bruxism may cause microcracks, which may lead to unexpected crown fractures and premature loss of teeth.