Remarkable stomatognathic development occurs in children during growth. Recently, dental cone beam CT has become popular for three-dimensional imaging diagnosis in pediatric dentistry. In this study, we reviewed 323 instances of dental cone beam CT use in 294 patients (184 boys, 110 girls) over the 5-year period from October 2008 to October 2013 at the Pediatric Dentistry Clinic of AichiGakuin University Hospital, with the following findings obtained.

1.Classified by purpose, the majority of CT examinations (n＝183) were performed for detailed examination of supernumerary teeth, followed by confirmation of location of permanent teeth (n＝ 75).

2.Letters of introduction were brought by 197 patients, while 97 were not referred. Of the referral cases, locative identification of supernumerary teeth was the most frequent reason for referral (n＝ 120).

3.Classified by age, 60 CT examinations were performed for patients aged 7 years and 59 for those aged 6 years. The mean age of all patients was 8.6 years.

4.The location with the greatest number of CT examinations was the anterior region of the maxilla (n ＝260).

5.Although the number of supernumerary teeth most frequently found was 1, the need to consider the possibility of multiple supernumerary teeth was suggested.

6.Regarding the direction of tooth eruption, an inverted supernumerary tooth was most frequently seen in cases with 1 supernumerary tooth, while combinations of inverted and normally oriented, and inverted and inverted most frequently occurred in cases with 2 supernumerary teeth.

7.The mean age of patients who underwent supernumerary tooth extraction was 7.5 years, with 7 being the most frequent, followed in order by 6 and 8 years, respectively. In some cases, periodic follow-up examinations without extraction were performed according to the location and degree of patient cooperation.

We investigated the number of visits to K dental clinic using information obtained from the clinic web page for the purpose of determining the relationship between number of web page visits and number of new patients. The relationships between number of visits to the web page and sessions (i.e., number of page visits), users (i.e., number of different visitors to the web page), average session time, and bounce rate (i.e., percentage of sessions in which visitor left the web site without interaction) using the 2-year “user summary report” (March 2012 to February 2014) compiled by the Google Analytics system, which considered various information regarding access to the designated page.

There was a negative correlation between the number of sessions in “period A” (September 2012 to August 2013) and new patients in “period B” (March 2013 to February 2014). The periods over lapped, as “B” started 6 months prior to the end of period “A”. Soon after the website was launched,the number of new patients who visited the clinic after visiting the website increased. However, over time, the number of new patients showed a decrease, even though the numbers of sessions and users increased. In addition, since September 2012, the percentage of access from portable devices increased, while that from desktop PCs decreased, the bounce rate increased, and the average session time decreased.

We present the results of two patients treated with both chemotherapy and surgery for neuroblastoma at an early age (stage III). Stage, age, MYCN oncogene status, and histologic category are prognostic factors in such cases. Those factors have been incorporated into risk-group classification based on the results of a risk-based clinical trial. Our first patient was diagnosed with a neuroblastoma at the age of 1 year 8 months. MYCN amplification was indicated, thus the case was classified as high risk. We used a 5-course chemotherapy regimen and autologous stem cell transplantation for a period of 6 months from the age of 1 year 10 months to 2 years 4 months. Dental abnormalities included short roots and arrested root development of the primary second molars, and permanent first molars and incisors, as well as microdontia of the first premolars and aplasia of the upper left permanent second molar. The second patient was diagnosed with a neuroblastoma at 10 months old. MYCN amplification was not indicated and the case was classified as intermediate risk. The neuroblastoma was treated with 5 courses of chemotherapy for 4 months from 10 months to 1 year 1 month old. This patient did not have any dental abnormalities. The chemotherapy regimen in the first case was more intensive as compared to the second. Disturbances in dental development in the first case compromised malocclusion, open bite, and crossbite. Orthodontic treatment for patients with severely disturbed root development should be given with light forces.

We treated 6 child patients for morphological improvement of excessive overjet due to a lip biting habit using an orthodontic device. Thereafter, oral muscle function therapy (MFT) and guidance for stopping the habit were given. Smooth disappearance of the lip biting habit was noted in all cases. Our study revealed the following findings.

1.Treatment for improving projecting teeth in children with a lip biting habit is likely more effective at an early stage, along with the guidance for stopping the habit.

2.Appropriate guidance and practice regarding MFT for child patients may contribute to stability of normal dentition and prevention of recurrence of lip biting habit.

3.Improved lip pressure might be possible when treatment for improving dentition is given with an orthodontic device, in addition to MFT.