The purpose of this investigation was to examine the relationship between measured values (rheological properties) of composite pastes, such as viscosity coefficient, peeling rate and external force (objective measurements), and a favorable property of such pastes discriminated by touch by dentists (subjective measurements). The rheological properties were examined using a balance beam plastometer. The subjective measurements were performed by eighteen young dentists and repeated four times. The subjective measurements related to four characteristics;hardness of paste (A), retention of shape (B), self-bonding properties (C) and release properties from an instrument for filling (D). There was a significant correlation between the log of the external force (log F) and the log of the peeling rate (logν) in all materials (r=0.950~0.997). A moderate correlation in all materials, except Degufill ultra, Heliomolar, Litefil IIA and Silux plus was also found between the log of the coefficient of viscosity (logη) and logν (r=0.870~0.995). The coefficient of correlation obtained from regression lines between the ratios of favorable properties (log PA, log PB and log PD) in the subjective test and log F or logηshowed a good approximation with a quadratic equation.

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Relationships between enthusiasms of teaching staff in directing graduate students of 5th grade in the Research Laboratory and the responses of the students were investigated on the basis of a questionnaire survey of Research Laboratory 2007 and documents of Research Laboratory 2006 and 2007. Eighty-eight percentage of the students were assigned to laboratories which they selected firstly, and 97% were assigned to laboratories which they selected either firstly or, at least, secondarily. Seventy-two percentage answered that laboratories, which the students were assigned to, made full preparations to receive the students. Eighty percentage answered that teaching staff had a great deal of enthusiasms on the Research Laboratories. Ninety-eight percentage answered that they made research works with great interests during the assignment period. A strong relationship was found between a questionnaire of whether or not the student had interests on research themes and that of whether or not they felt enthusiasms of teaching staff. Another strong relationship was found between a questionnaire of whether or not the students had interests on their research themes and that of whether or not they investigated literatures on them actively. Thus, the students responded sensitively for the enthusiasms of teaching staff on Research Laboratories and showed more interests on the research themes. It is also considered that students lost their interests on the themes when the teaching staff showed no enthusiasms. Further, no large difference was found in the number of assigned students between laboratories in basic dental science (including laboratories in general education) and laboratories in clinical dental science.

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The number of users at the Kyushu Dental College Library was analyzed between 2002 April and 2008 July. The annual number of the library users averaged 69,810, and the number of weekday users averaged 291. In 2007, when the new library had opened, the user was more than that of old library by 14,039 for annual number of users, and by 39 for weekday. Monthly and daily user was the most at February and September, and the least at August. Weekend library opening had started in 2007 April, and the number of weekend user tended to increase in 2008 compared to that in 2007. Library users between 20:00 and 22:00, where it is executed from 2008 April, increased gradually from April to July. The time zone where the number of weekday user is the most was 16:00~17:00, and many next 12:00~13:00 and 14:00~15:00, but that of weekend user unlike weekday was the most at 19:00~20:00. Although library opening time extension becomes improvement of the most useful service for the user, the detailed analyses of library users by month, day of the week or time zone, or by weekday or weekend may be needed for more efficient service offer.

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We describe a case of recurrent ameloblastoma in left mandible where segmental resection was performed and reconstructed using distraction osteogenesis with segmental bone transport.We present a 52-year-old male patient with a complaint of painless gingival swelling in the left mandible. He had a history of treatment for ameloblastoma 26 years earlier in the left mandibular first molar area. Marginal mandibular resection along with a wide range of surrounding soft tissues was performed. Distraction osteogenesis was applied for the mandibular reconstruction with segmental bone transport method, after fixing the inferior border of mandible with a dynamic bridging plate for added strength.
Distraction osteogenesis is a versatile method compared to simple bone grafts to reconstruct mandibular defects with new regenerated bone and elongated soft tissue such as mucosa and nerve. However, the strength of the remaining mandibular bone after marginal resection was insufficuent to reconstruct using the segmental bone transport method in this case. Some reinforcement device was needed to add strength to the mandible without compromising mobility of the bone transport segment.
Therefore, a dynamic bridging plate, which could be bent to the desired contour was applied as a reinforcement device to the inferior border of the mandible. We could secure the distractor device on the buccal side of the mandible to achieve the better alignment of the regenerative tissue without compromising on support provided by the dynamic bridging plate fixed in the inferior portion. As a result, good regeneration of new bone and soft tissues was achieved. Five years after surgery, the patient has good functional results with a mandibular partial denture and without any recurrence of the tumor.
In conclusion, segmental bone transport with a dynamic bridging plate was an effective method which can be applied after surgery of malignant tumors as well as benign tumors for the reconstruction of the defected areas of bone and soft tissues. Furthermore, distraction osteogenesis has potential for reconstruciton of any large bony and soft tissue defects if provided with stable reinforcement plating.

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A case of trismus caused by glass foreign bodies buried deep in the cheek region is presented in this paper. An 81-year-old man was referred to our hospital because of a limited range of mouth opening, persisting for 1 year 9 months after sustaining a facial injury caused by backward fall into a glass frame. The mouth opening was limited to 20mm and diffuse induration was in the left buccal region. Radiographic examination showed two radiopaque masses in the left buccal space. During the operation, two buried pieces of the glass which were located in the buccal space and buccinator were removed. Many papers describe the difficulty in locating the glass foreign bodies using plane radiographic examination. In this case, we could locate glass foreign bodies with digital radiographic examination. Then we compared the ability to locate the glass foreign bodies with plain radiographic and digital radiographic examinations. As a result, we were able to locate the 2-4mm thick glass foreign bodies with digital radiographic examination.

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This case report describes a case of nasoalveolar cyst arising in a 58-year-old woman with severe resorption of the alveolar bone. The patient was referred to our hospital because of swelling of the left nasolabial region. Panoramic radiography and computed tomography revealed a unilocular radiolucent lesion in the left maxillary alveolar bone. The severe resorption of the alveolar bone reached the lower palatal periosteum. The lesion was completely extirpated under general anesthesia. Histopathologically, the cyst wall consisted of squamous or cuboidal epithelium.

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