Rigid internal fixation after bilateral sagittal split osteotomy (BSSO) is routinely used worldwide. However, stability of the mandible one year after surgery with two bicortical screws at the superior border or a four-hole straight miniplate after the BSSO has not been studied clinically. Therfore, the purpose of this study was to compare two bicortical 2.7 mmφ screws with a four-hole straight miniplate after the BSSO and to discuss which method is more stable. The ∠MP-FH with two bicortical 2.7 mmφ screws showed a significantly larger increase during the first year, compared to those with a four-hole straight miniplate. Thus result suggest that a single four-hole straight miniplate can provide better postsurgical stability than two bicortical 2.7 mmφ screws for sagittal split setback.

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The purpose of this study was to evaluate jaw, head and body position-related changes in upper airway dimensions and maximum forced inspiratory airflow. Fifteen male normal subjects were selected and underwent magnetic resonance imaging in the following five different jaw, head and body positions: (1) supine with no jaw protrusion; (2) supine with jaw protrusion; (3) lateral decubitus with jaw protrusion; (4) supine, head rotation with jaw protrusion; (5) pronation, head rotation with jaw protrusion. The dimensional changes of the upper airway were measured according to the magnetic resonance images. To assess the changes in ventilation, the maximum forced inspiratory airflow was tested using a spirometer. This was accomplished with the subjects placed in the positions previously described. Data of airway dimensions and inspiratory velocity were reported using descriptive statistics. The results showed that upper airway dimensions and maximum forced inspiratory airflow changed by the changes of jaw, head and body positions. Jaw protrusion and head rotation could enlarge the upper airway dimensions and provided more maximum forced inspiratory airflow. These positions may prove beneficial for alleviating the symptoms of patients with obstructive sleep apnea syndrome.

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Denture plaque control is very important for elderly patients wearing removable dentures to keep their oral cavity healthy. We thought that a titanium dioxide solution has effect of removing of denture plaque. The purpose of this study was to evaluate the effect of titanium dioxide solution against deposition of stains (cigarette, tea, curry) on polymethylmethacrylate resin plate. The results suggested that titanium dioxide solution was useful foe not only preventing from the deposition of stains but also removing stains.

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The "Open Campus" event is designed to present college facilities to prospective students who are considering submitting an application for admission as a part of a promotional campaign to attract student interest and increase enrollment. Kyushu Dental College (previously Fukuoka Prefectural College) was reorganized into a public university corporation in 2006. In accordance with a newly-established admission policy, a new "Open Campus" project was planned and implemented in 2007 and 2008. Herein, an overview of surveys regarding satisfaction by the participants and their results are reported. In comparison to the "Open Campus" project conducted in 2006, four programs were added in 2007 and three in 2008, which were made bidirectional and selectable by the participants. The number of participants was 154 in 2007 and 204 in 2008, in both cases larger than the number in 2006. As for all participants, those from inside and outside of Fukuoka Prefecture were roughly equal in number, whereas 55% of the participating high-school students were from outside of Fukuoka Prefecture. Ninety-nine percent of the participants answered positively "satisfied" or "moderately satisfied" in regard to the programs, demonstrating that nearly all had a favorable experience with the "Open Campus" . Additional collective effort by both faculty and students is considered necessary to make the "Open Campus" programs even more attractive.

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The aim of the present study was to estimate the effects of risedronate on endochondral and membranous ossifications of the tibia in growing rats treated with glucocorticoid (GC). 5-week-old male Wistar rats were given oral risedronate in doses of 0 (saline), 0.5, or 1.0 mg/ kg/day for 4 weeks following administration of oral prednisolone in doses of 30 mg/kg/2 days for 6 weeks. All rats were given a subcutaneous injection of calcein (8 mg/kg body weight) on days 10 and 3 prior to sacrifice. At the end of the experiment, bone histomorphometric analysis of trabecular bone at the proximal metaphysis and cortical bone at the diaphysis of the right tibia was performed, and the mechanical properties of the proximal metaphysis and diaphysis of the left tibia were evaluated. In the trabecular bone GC significantly decreased bone resorption and bone formation in the tibial metaphysis. In addition, 6 weeks GC administration did not affect the mechanical properties, but after 4 weeks of saline treatment the breaking energy was significantly decreased. In cortical bone 6 weeks of GC administration significantly decreased periosteal and endocortical bone formation, and in addition significantly decreased breaking energy, and this reduction continued following 4 weeks of saline treatment. Risedronate increased the trabecular number (Tb.N) and decreased trabecular separation (Tb.Sp) by decreasing bone resorption and bone formation, resulting in improved GC-induced decreases in breaking energy at the tibial metaphysis. In the cortical bone risedronate improved GC-induced decrease in breaking energy by increasing the mineral apposition rate (MAR). These findings show that risedronate improved GC-induced decreases in mechanical properties both of the endochondral and membranous ossification portions, but the mechanisms of improvement in bone strength in those two sites is regulated differently in the growing rat tibia.

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The chemical irrigation of root canal has been usually performed by combined treatment with 3-10% sodium hypochlorite and 3% hydrogen peroxide (Oxydol) as the most useful procedure. It is, however, contraindicative for an acute apical inflammation and may give unexpected effects on soft tissues and clothes if it inadvertently comes into contact with them. The present study was scheduled to find out the utility of electrolyzed neutral water for sterilization of root canal as an alternative to chemical agents. It has been previously reported that neutral water shows excellent bactericidal effects with few side effects on vital tissues and environments.
The prepared canal walls of extracted single-rooted teeth were contaminated with Staphylococcus aureus 209P or Streptococcus mutans. The canals were then washed for one minute with neutral water or agents alternately using 10% sodium hypochlorite and Oxydol. The sterilization effects of them on the canal walls were evaluated in terms of the number of surviving bacteria. Both types of bacteria in the canal were thoroughly removed by the agents after one-minute washing using a syringe. When the canal was washed by syringe with the neutral water, some numbers of surviving bacteria remained in one sample out of three. As the water showed sufficient sterilization effect for exterminating the bacteria within a short time when they were mixed in a glass tube, the reduction of the effect in the canal might be due to the exhausted effective residual chloride of the water by its reaction with organic materials in the canal. The remaining number, however, statistically exhibited no significant difference from that of the agents. Ultrasonic washing with the neutral water could further reduce the number of surviving bacteria, and no Staphylococcus aureus 209P were found in the canal after washing although only a small number of Streptococcus mutans could still survive. The neutral water gel developed by the authors showed better sterilization effects because it contained higher concentration of residual chloride and could stay in situ in the canal for longer time. When the gel was filled in the canal after washing with the neutral water, the sterilization effects reached completely 100% for the contaminated canal. It is expected that gel filled in the canal after washing until the next washing treatment may be able to inhibit the growth of existing bacteria as well as the invasion of new bacteria.
When the dentin specimen was dynamically immersed in the tested media, it tended to whiten and decrease in volume in sodium hypochlorite while no change was found in the neutral water and gel.
The foregoing results suggest that the combined use of neutral water and gel may be well applicable for sterilization of canal alternative to the chemical agents from the standpoints of effective sterilization ability and subsequent maintenance, biological safety and easy manipulation without concerning any side effects.

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Since little is known about their actual conditions of health, we conducted a mark-sheet questionnaire investigation of dental students in the 2^nd through the 6^th years of study at Kyushu Dental College, as part of a program of educational reform. The survey was carried out for 489 individuals. The percentage of students responding to the questionnaire was 82.8 percent.
As for questions concerning health, 25.4 percent of the students have been more or less worried about health matters, and 10.8 percent have gone to the hospital as outpatients. 27.1 percent reported a mental affliction. These ratios tended to be lower as the number of years of study increased from two to five, but the 6^th year students had a high response rate. Males were more afflicted by health and mental problems than females. The rate of utilizing the college health office and the counseling room was also nearly the same. Half of the students answered that peer relationships with friends were good or very good, and 46.6 percent of students consulted with friends about an affliction. A very low percentage (12.4 percent) conferred with college stuff about an affliction, and the percentage became lower as the number of years of study increased. It was concluded that the college health office and the counseling room should be fully implemented to support students' physical and mental well-being and to further improve their education.

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