This study concerned exposure to volatile organic compounds in dentistry. Bulk samples of the resins used in dental laboratories were collected. The main components in the headspace of the containers of the bulk samples were identified by solid phase microextraction in conjunction with gas chromatography and mass spectrometry. Personal samples in dental laboratories and a clinic were taken using diffusive samplers (3M Organic Monitor) and quantified by employing gas chromatography with a flame ionization detector. Questionnaires were administered while personal air sampling was carried out. The predominant and common volatile organic vapor found in the bulk samples was methyl methacrylate (MMA). The profile of exposure to MMA in similar exposure groups approximated to a log-normal distribution. Although the exposure level to MMA found in this study was less than the occupational exposure limits, handling resins for prostheses in dental laboratories may lead to exposure to several volatile organic compounds other than MMA. Additionally, respondents in dental laboratories had relatively high exposure to MMA and relatively high response levels concerning personal complaints, in particular, headache, eye itching, burning or irritation, and a harsh throat sensation or thirst. A comprehensive exposure assessment for all chemicals is required as are and toxicological studies concerning chemicals lacking information related to biological effects, such as N, N, 3-trimethyl benzenamine.

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[Introduction] Recently, FKO is widely used as a functional orthodontic appliance. Patients normally use the device at night when FKO applies its orthodontic force to its maximum. However, because FKO is a removable orthodontic appliance, during clinical treatment, the patient often doesn't keep to the planned schedule. Therefore, the result of a procedure may not turn out exactly as anticipated. It was thought that the patient may dislike using the appliance because of a decrease in oral respiration capacity, and therefore desired to shorten the usage time as a result The purpose, therefore, of this study was to investigate whether the use of FKO decreased the oral respiration capacity of patients. No evidence was found supporting a change in patient's respiration volume when FKO was used, even though various documents were examined. [Methods] The study subjects were six adults (three male and three female), who used test FKOs which were produced by the regular methods. The subjects then took turns to measure respiration of these unmodified FKOs. After that　sevral holes were made in the front of the de­vice (boned on the device's size) and the results were then re-measured. The measurement time was 15 minutes, with the first five minutes being excluded as a control. The study subjects were allowed to read while measurement of CO2 volume and respiration rate was in progress to help prevent undue attention on their breathing. The following nine modes were investigated: CDNon­ FKO, Free breathing(NF), ®Non- FKO, Nasal respiration only (NN), @Non- FKO, Oral respiration only (NM), @Regular FKO, Free breathing (FF), ®Regular FKO, Nasal respiration only (FN), @Regular FKO, Oral respiration only (FM), (l)Modified FKO, Free breathing (FHF), @ Modified FKO, Nasal respiration only (FHN), ®Modified FKO, Oral respiration only (FHM). We then analyzed the result using multiple comparison authorization (Bonferroni authorization). [Results] A significant difference was not seen between FM and FHM. A significant difference was seen however, between FM and all other measurements. The increase in FHM volume was larger than that seen in the FM volume. However a significant difference was not seen between FHM and any of the other measurements including FM. [Discussion & conclusion] There was no effect on the respiratory volume of normally nose breathers when FKO was applied. For oral respiration patients, some strategies for FKO usage were needed. As for the decrease of respiratory volume of oral respiration with FKO applied, it was suggested that there should be some improvements on the techniques or styles for hole drilling, even if it was an effective part of a previous method.

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Recently, reforms in dental education have been remarkable and the demands level to the students increased, too. The situation of overall stress can be seen especially with such tests as the OSCE (Objective Structured Clinical Examination) and CBT (Computer Based Training) for students. The OSCE was carried out in fiscal year 2006, and there was concern about peculiar ten­sion different from that in the written test for students. The aim of this study was to examine the students' psychological condition and the influence on the skill test of the OSCE. The subjects of this study were 84 third-year students treated at Kyushu Dental College in fiscal 2006. Before implementing the simulation test, the degree of anxiety was measured using State-Trait Anxiety Inventory (STAI) followed by the determination of the salivary chromogranin A (CgA) concentration, a biochemical marker of psychosomatic stress, the degree of tension being measured using blood pressure and pulse. The simulation test performed was tooth-brushing guidance in the field of periodontology, the score for which was determined with examination pa­ pers with a top score of 20. After completion of this test, STAI and CgA, blood pressure and pulse were measured again. In the multiple regression analysis for which the response variable was the score on the simulation test before the examination, the influence was focused on Trait, pulse, and CgA. In the multiple regression analysis, for which the response variable was the score on the simulation test after the examination, the influence was focused on the average of blood pressure, pulse, and CgA. From the results described above, it was determined that the psychologic and physiological stress in regards to the simulation test was significant for the students. OSCE education was recommended, and also the importance of guidance which takes into consideration psychological situation.

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This report describes a rare case of a mucous retention cyst m the middle of the oral floor. 51-year-old man was referred to our department with the chief complaint of a painless swelling in the middle of oral floor, which had persisted for 1 year. CT and MRI images showed a large mass in the middle of oral floor. Extirpation of the mass was performed under general anesthesia. The mass was unrelated to the sublingual gland or Wharton's duct. The histological diagnosis was mucous retention cyst. After 1 year 10 months of follow-up, there have been no signs or symptoms of recurrence.

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