Katsuhiko Taura

Influence of tooth-to-denture-base discrepancy on space closure following premature loss of deciduous teeth

Influence of tooth-to-denture-base discrepancy on so-called physiologic migration of the first molar was studied on serial dental casts of 116 boys and girls, obtained through a dental health program for school children in an area in which there was no dentist. The alteration of spaces following premature loss of deciduous molars was examined comparing the anterior to posterior discrepancies between tooth and denture base. Modes of space alteration showed positive correlation with the size of the discrepancy, especially in the mandibular dental arches. The space deficiency in the posterior region seemed to have a positive effect on the mesial migration of the first molar. Mesial migration of the first molar seems to be pathologic rather than physiologic and is strongly affected by tooth-to-denture-base discrepancies. Space maintenance does not seem to be useful, because it is not necessary in minimum discrepancy cases and is not effective in severe discrepancy cases.

Roles of dentists and dental hygienists in two major earthquakes.

BACKGROUND In recent years, disasters that overwhelm the capacity of humans have been frequent. However, international cooperation has been swift as a result of advances in transportation, enabling the more prompt administration of First Aid. METHODS We have had two opportunities to observe outcomes in oral hygiene immediately after and 10 months after two different major disasters. RESULTS The types of food provided to survivors altered their sense of taste and resulted in the occurrence of dental caries several months after an earthquake. In addition, it is difficult to practise good oral hygiene in the aftermath of a disaster. CONCLUSIONS We observed the occurrence of previously undocumented problems related to dental issues, such as changes in childrens sense of taste caused by unfamiliar types of food provided in relief shelters. Dentists and dental hygienists who are involved in the relief of survivors in the immediate aftermath of a natural disaster should focus on maintaining good oral health in order to prevent the occurrence of dental caries.

National survey on school-based fluoride mouth-rinsing programme in Japan: regional spread conditions from preschool to junior high school in 2010

Aims We surveyed the state of implementation of the school-based fluoride mouth-rinsing programme (S-FMR) in schools in Japan from March 2010. Methods Questionnaires on the implementation status of S-FMR in each type of school (including preschool and kindergarten) were sent by post to the oral health administration departments of all 47 prefectures and 89 cities (18 ordinance-designated cities, 23 special wards, 41 core cities and seven public health centres in ordinance-designated cities) with public health centres. Results The S-FMR implementation rate was low, at only 11% of all schools in Japan and only 6% of all participating school children aged 4–14 years. In many regions, the S-FMR was implemented more widely and received higher participation from children in either elementary schools and junior high schools or preschools and kindergartens. Conclusions Inter-prefectural disparities were seen in S-FMR implementation, as some prefectures and cities did not include topical fluoride application in their health promotion plans, and some local public bodies did not include targets for fluoride mouth-rinsing. To reduce this disparity in Japan where systemic fluoride application is not performed, each local public body must consider implementing the S-FMR as a public health measure. We propose using the results of this survey as basic data for formulating S-FMR goals (numerical targets) and adopting S-FMR as a concrete measure in the second Healthy Japan 21, to be launched in the fiscal year for 2013, and within the basic matters of the Act Concerning the Promotion of Dental and Oral Health.

Prediction of future number of remaining teeth of Japanese elderly, based on data from the national survey of dental diseases in Japan

“8020” Movement (retain 20 natural teeth at the age of 80) has proposed from 1989 for prolonging the life span of teeth. The purpose of this study is to predict the attainment time “8020”. We analyze the data of the nine national surveys of dental diseases in Japan conducted every 6 years from 1957 through 2005 to determine the actual trend of retention of natural teeth. The average numbers of remaining teeth of ten 6-year stratified age groups are determined by calculating the rates of tooth loss in 6 years of corresponding age groups for the period 1957 through 2005. Future rates of tooth loss are then estimated using regression analysis on the assumption that the present rate of improvements in dental care, preventive measures, and public awareness for oral health would continue. Our estimation suggests that the “8020” goal would not be attained until after 2029 or 2035.

National survey on the school-based fluoride mouth rinsing program in Japan: proposition regarding final assessment of Healthy Japan 21 in 2010, and in 2020

The purpose of this study is to clarify the spread conditions of the school-based fluoride mouth rinsing (s-FMR) program since 1983 and to estimate the total number of schools and children who would be participating in the s-FMR for proposition regarding final assessment of Healthy Japan 21 in 2010, and to calculate the estimated number in 2020. In 2008, the total number of schools and children who participated in the program were 6,433 and 674,141, respectively. It shows that the number of children participating in the program corresponds to 5.1% of the same-aged population. The estimated number of schools and children participating in the program would approximately be 7,262 and 7,386,231 in 2010, and 14,770, and 1,523,632 in 2020, respectively, calculated on basis of data from 1983 to 2008. We need the cooperation of dental organizations, dental schools, and municipal corporations to achieve the goals in the s-FMR.

Acoustic mineral density measurement to evaluate clinical demineralized lesions

The aim of this study is to measure the acoustic characteristics of human extracted teeth with sound or dentine caries lesion by using an ultrasonic device and to compare the readouts to the diagnosis based on the DIAGNOdent (KaVo institution, Germany) and dyed with Caries-Check (Nishika institution, Tokyo).

A new intra-oral pressure monitor for screening swallowing dysfunction

Swallowing, which is important for eating and drinking for survival, is one of the basic functions of the mouth. The purpose of this study was to develop a safe and easily-handleable measuring device to evaluate swallowing processes in younger generations. An intra-oral pressure-measuring device estimated the intra-oral positive and negative pressures produced by sucking or blowing. The results indicated that the maximal positive pressure or minimal negative pressure increased or decreased depending upon age. This suggests that the function to produce intra-oral negative pressure, which was made with lip and faucial isthmus closure for sucking, and positive pressure, which was made with lip closure for blowing, was developed with age or physical strength. This simple measuring system of oral pressure was useful in fieldworks for screening oral dysfunction among all generations, not depending upon the condition of tooth or dentition.

Difference between age generation of oral health examination in a rural town

Oral health examinations were held in summer continuously for 2 years with general health checks in a rural town. We included oral health check, practice of oral cleaning, and measurement of oral malodor in the examination. Aim of this study was to examine the difference of impression in the oral health examination between younger and older participants by questionnaires. No difference was found between male and female ratio in each generation. Also, no difference was seen as for ratio of joiners of oral cleaning and ratio of their satisfaction after the practice. Significant difference between two generations was seen as for strong satisfaction ratio with explanation about the result of oral malodor, and effective motivation ratio for oral hygiene caused by measurement of oral malodor. The oral health examination held with general checks with measurement of oral malodor seemed more impressive to older generation.