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The clinical practice of sports dentistry by the sixth-year students of The Tokyo Medical and Dental University Faculty of Dentistry was carried out by the students in order to learn about the basic knowledge of mouthguard fabrication methods. Our present research was conducted by a questionnaire on the students' evaluation of the sports dentistry clinical practice. In response to the question related to the level of satisfaction and whether it is beneficial to clinical practice of sports dentistry, 82% of the students answered "satisfied" including "satisfied a little" and 87% "beneficial" including "slightly beneficial". Based on the questionnaire results, the clinical practice of sports dentistry was confirmed to have an educational effect on the students at some level. In addition, the results suggested that mouthguard fabrication may possibly provide motivation for students to learn sports dentistry. [ABSTRACT FROM AUTHOR]

Purpose: Saliva plays an important role in the health of soft and hard tissues in the oral cavity. Studies have shown that a reduction of salivary secretion causes a decrease of oral sugar clearance capacity in humans, thereby resulting in an increase in dental caries. The purpose of this study was to investigate possible inhibitory effects of fluid replacement on exercise-induced declines of salivary secretion in association with the physical effort of bicycle ergometer exercise in healthy volunteer subjects. Material and methods: Eight female and 14 male healthy volunteers (mean age 26.9 years) performed a 40-min bicycle ergometer exercise test with an 80% level of maximum heart rate for the following 3 conditions of fluid replacement ; 1) No fluid replacement, 2) Fluid replacement with a natural mineral water, 3) Fluid replacement with a sports drink. Timing and intake of fluid replacements during the exercise test were placed at the subject's disposal. Paraffin stimulated whole saliva samples were collected before, during, immediately after, 30-mins after and 60-mins after the test to measure the salivary flow, pH, buffering capacity and colony-forming units of Streptococcus mutans. Results: The mean intake of fluid replacements with a natural mineral water and a sports drink were 502.7 ml and 690.7 ml, respectively (paired t-test, p<0.01). While the salivary flow and buffering capacity after exercise for the condition of no fluid replacement decreased by 1.87 ml (31.3%) and 0.15 pH units, respectively, the salivary flow and buffering capacity after exercise for the conditions of fluid replacement with natural mineral water and a sports drink decreased by 1.05 ml (18.0%) and 0.14 pH units, and 0.56 ml (9.3%) and 0.33 pH units, respectively (ANOVA, p<0.05). The number of colony forming units of Streptococcus mutans did not change for any condition of fluid replacement after exercise (X² test, p=0.167-0.200). Conclusion: This study indicates that fluid replacement during exercise is an effective way of suppressing the reduction of saliva flow as well as for preventing dehydration, and suggests that fluid replacement during exercise contributes to maintain a better oral environment for athletes. [ABSTRACT FROM AUTHOR]

We report on the fabrication of a custom faceguard (FG) for a soccer player injured with a complex fracture of the zygomatic bone and orbit. The patient was a 29-year-old male. He came to our clinic two months after open reduction with titanium plates. His chief concern was making a FG to play soccer safely and without anxiety. Treatment: 1 We made a facial moulage with an irreversible hydrocolloid impression material and an impression plaster material. 2 We poured the moulage with Type IV dental stone to make the facial cast. In designing the outline of the FG, it was critical to leave the eyes uncovered to avoid narrowing the field of vision, especially the uninjured side where there was not adequate space between the FG and the injured area. We softened a sheet of 3.2 mm thick thermoplastic material in hot water (about 70-75°C), and applied and molded it over the cast with right finger pressure. After the material had cooled, we trimmed it to the desired outline drawn on the cast. Then, we used adhesive to adhere 1.6 mm (outside) - and 3.2 mm (inside) -thick rubber cushioning materials to both surfaces of the sheet. Finally, we sewed the edges of cushioning liner materials of FG. 3 After the fitting, the FG was secured on the patient using two stretch bands with hook and loop fasteners. 4 For a while after using the FG, he complained about unwanted movement of the FG when doing a header maneuver. Therefore, we modified the shape of the metopic area. At the same time, a questionnaire survey was done, which included the visual analog scale concerning the feeling and field of vision. As a result, he could use the FG comfortably except the field of vision slightly narrower. Summary: To popularize the use of FG in the future, each case should devise it in consideration of the injured area, symptoms, progress of cure, characteristic of the sport, and position, and so on. [ABSTRACT FROM AUTHOR]

Size-specific dose estimates (SSDEs) are dose indices that account for differences in body shape in computed tomography (CT) scans, allowing the evaluation of approximate absorbed doses in any cross section that could not be obtained with the volume CT dose index (CTDI vol ). When using automatic exposure control (AEC), CTDI vol is modulated in the body axis direction, but the value displayed after the examination is the mean CTDI vol for the entire scan, and it is expected that the SSDE value will change depending on which value is used in the calculation. In this study, using a human body phantom, we examined the influence of whether the mean CTDI vol or the modulation value for each slice is used to calculate the SSDE on local organ dose evaluation. A program to calculate water equivalent diameter according to the procedure in the American Association of Physicists in Medicine Report No. 220 was developed and compared. As a result, SSDE calculated using the mean CTDI vol (local-SSDE mean ) overestimated organ doses in the lung region by 18%-56% compared with those calculated by a web system for evaluating CT exposure doses (WAZA-ARIv2, Japan). In contrast, local-SSDE modulated , which was calculated using the modulated value of the CTDI vol , was able to estimate the organ dose with a relative error of 10%-13%. The average local-SSDE over the entire body axis direction was not significantly different between the two methods, regardless of which method was used for CTDI vol . If the mean CTDI vol is stored in the Digital Imaging and Communications in Medicine (DICOM) header tag (0018, 9345) of the CT image and the modulated CTDI vol value is not available for each slice, the calculated local SSDE will contain many errors and will not correctly reflect the organ doses at the scan region. In such cases, it is available to use the method of evaluating local organ doses by multiplying the SSDE, which is the average of the SSDE for the entire scan, by a factor for each organ.

Pemetrexedis a key drug in the first and second -line therapy for non-small-cell lung cancer. It exhibits an increased area under the plasma drug concentration-time curve, and it has a prolonged half -life when administered to patients with reduced renal function, resulting in a high frequency of neutropenia. Accordingly, pemetrexed is administered to these patients with caution. Herein, we retrospectively investigated the background characteristics of patients with a creatinine clearance rate (Ccr) of<45 mL/min, who experienced severe adverse events due to pemetrexed. Thirty-eight patients with a Ccr of <45 mL/min were administered pemetrexed. Of these patients, 13 (34%) developed severe adverse events (≥Grade 3) such as neutropenia, thrombocytopenia, and nausea. Multiple logistic regression analysis revealed that a Ccr of <30 mL/min (p= 0.033) and the concomitant use of non-steroidal anti-inflammatory drugs (p=0.012) were significant risk factors for adverse events. Therefore, whenever possible, pemetrexed administration should be avoided in patients with a Ccr of <30 mL/ min and in those receiving concomitant non-steroidal anti-inflammatory drugs.

Various factors, including renal function and the combination of nonsteroidal anti-inflammatory drugs, influence the pharmacokinetics of pemetrexed. In this study, we aimed to determine the risk factors for severe adverse events associated with pemetrexed administration. We retrospectively examined the medical records of 82 patients who received pemetrexed. Multiple logistic regression analysis indicated that a creatinine clearance (CCr) of less than 45 mL/min and administration of pemetrexed as early-line treatment were significant risk factors. We then retrospectively compared the adverse events associated with pemetrexed between patients with normal renal function (CCr≥45 mL/min) and those with impaired renal function (CCr<45 mL/min). With regard to hematological toxicity, the frequency of occurrence of grade 3 neutropenia was significantly higher among patients with a CCr of <45 mL/min. With regard to non-hematological toxicity, the frequency of occurrence of grade 2 or higher nausea was significantly higher among patients with a CCr of <45 mL/min. However, the efficacy of pemetrexed did not differ significantly between the 2 groups. Our findings suggest that, for patients with a decline in renal function (CCr <45 mL/min), attention must be paid to the possibility of serious adverse events such as neutropenia and nausea when considering the administration of pemetrexed.