Mucount® and Cariostat® are caries-activity tests based on oral bacteria which have been widely used in clinical dentistry. In this study, these caries-activity tests were carried out to 10 pre-school children. Simultaneously, number of Streptococcus mutans in dental plaque was measured by species-specific DNA probe method, and relationship between the cariesactivity tests and number of S. mutans was examined. Although Mucount® was effective in detection of S. mutans in saliva, the result did not reflect number of S. mutans in dental plaque. In contrast, Cariostat® which examines acid production by bacteria in dental plaque was not also associated with number of S. mutans in dental plaque. These results suggested that both Mucount® and Cariostat® may not be adaptive as one of caries risk factors.

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In order to perform better dental treatment, it is important that dentists have good communication with their patients and understand their feelings. However, it is also a fact that the number of dentists who cannot communicate sufficiently has increased, and this has become a social problem. A new curriculum “Society and Dental Treatment” has been created as a means of improving this problem. This course aims at attitude education, including “reliance, cooperation, and cooperative relationships”. This time, the course Elderly Welfare and Oral Health, a second-year course, was offered and examined by the Department of Geriatric Dentistry. The training methods were shown below. In the waiting room, each student explains the details of the training to the patient and obtains his/her consent. After that, the student communicates various matters with the patient. The results showed that favorable findings were obtained for the assessment item “Able to communicate with patients while considering their feelings”. However, assessments were poor for items “Able to understand concerns of daily living for patients with oral diseases” and “Able to understand the functions of the dental hospital as a tertiary medical institution”. Regarding usefulness of the training, 91% of the students answered that the training was necessary, and none of the students considered it to be unnecessary. Some problems regarding individual differences in the amount of time spent on the training were also made clear, although the training was very significant for the student. Furthermore, in order to make it better, the necessity of resolving problems and carrying out continuous self-check and assessment was suggested. Key words : patient-accompanying training, communication, considering patient's feelings, understanding the hospital function.

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Bisphenol A is one of a endocrine disruptor substances with an estrogenic reactivity, and some Light-cured restorative composite resin contain the compound synthesized using BPA as a raw material. When such a light-cured composite resin is used inside the oral cavity, it is conceivable that BPA derived from the compound synthesized from BPA may be released into the saliva. In this study, therefore, an enzyme-linked immunosorbent assay (ELISA) capable of assaying multiple samples simultaneously was focused, and the elute from a Bis-GMA base light-cured restorative composite resin was fractionated and collected by means of high-performance liquid chromatography (HPLC) and assayed using ELISA, and BPA was identified as a bisphenol A-like immunoreactive substances. Then, a piece of a light-cured composite resin and 20 ml double distilled water were kept in subject's oral cavity for 30 s. The double distilled water and saliva were retrieved entirely, and the BPA eluted into the saliva was assayed using ELISA. As a result, every gargle samples showed the elution of trace BPA. The elution of BPA began immediately after starting the experiment and showed tendencies to increase until 5 min and to decrease 10 min later.

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This study was carried out to determine statistical information concerning the crowns and the fixed partial dentures (total number, type and rate of crowns, number of vital or non-vital abutment teeth, etc.) which were placed in the outpatients in the Department of Fixed Prosthodontics at Showa University Dental Hospital from April 2001 to March2002.
The following results were as follows :
(1) The total number of crowns and fixed partial dentures (FPDs) were produced 956; among them, crowns totaled 778 (81.4%) and FPDs, 178 (18.6%).
(2) Most of the crowns were full cast crowns (382, 49.1%); the second most commonly produced were resin-faced cast crowns (197, 25.3%); the third were porcelain-fused-to-metal crowns (154, 19.8%).
(3) Resin-faced cast crowns and porcelain-fused-to-metal crowns were most commonly used for the anterior teeth; full cast crowns and porcelain-fused-to-metal crowns, for the premolar teeth; full cast crowns, for the molar teeth.
(4) FPDs located in the posterior region were 52.2%; the antero-posterior region were 28.1%; the anterior region were 19.7%.
(5) With regard to the relationship between the missing teeth and the abutment teeth of the FPDs, three-unit FPDs (one missing tooth with two abutment teeth) were most frequently treated in all regions.
(6) The crowns covered by the insurance dental service were 72.4%; the FPDs were 66.9%.
(7) Concerning the abutment teeth of the crowns, non-vital teeth were 82.1%, implant abutments were 7.5%; non-vital teeth of the FPDs were 73.9%; implant abutments were 0.5%.

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Although the tripod marking method is conventionally used to remount models surveyors, the error nor simplicity of the wearing angle of a model are not clear. In this study, the remounting of models on surveyors was performed using the tripod marking method and a new method that employs a level with a magnet. The methods were compared in terms of reproducibility and simplicity. Reproducibility and simplicity were better using the new method. In conclusion, it is suggested that the new method is useful for remounting models on surveyors.

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