In the present study, we developed a novel color scale for visual assessment, conforming to theoretical color changes of a gum, to evaluate m a s t i c a t o r y p e r f o r m a n c e ; m o r e o v e r , w e investigated the reliability and validity of this evaluation method using the color scale. Ten participants (aged 26–30 years) with natural dentition chewed the gum at several chewing strokes. Changes in color were measured using a c o l o r i m e t e r , a n d t h e n , l i n e a r r e g r e s s i o n expressions that represented changes in gum color were derived. The color scale was developed using these regression expressions. Thirty-two chewed gums were evaluated using colorimeter and were assessed three times using the color scale by six dentists aged 25–27 (mean, 25.8) years, six preclinical dental students aged 21–23 (mean, 22.2) years, and six elderly individuals aged 68–84 (mean, 74.0) years. The intrarater and interrater reliability of evaluations was assessed using intraclass correlation coefficients. Validity of the method compared with a colorimeter was assessed using Spearman’s rank correlation coefficient. All intraclass correlation coefficients were > 0.90, and Spearman’s rank-correlation coefficients were > 0.95 in all groups. These results indicated that the evaluation method of the color-changeable chewing gum using the newly developed color scale is reliable and valid.

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The aim of this study was to compare father-infant interaction with mother-infant interaction, and explore differences and similarities between parents. Related factors for quality of father-infant interaction were also examined. Sixteen pairs of parents with infants aged 0 to 36 months were observed for play interaction between parents and their children. Results suggested no significant differences between parents, but children’s interactions were significantly more contingent with fathers than mothers (p =.045). Significant correlations between parents were found in socialemotional growth fostering encouragement for children during interaction (ρ =.73, p =.001). Paternal depressive symptoms were significantly correlated to paternal sensitivity to child’s cues (ρ =-.59, p =.017).

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Background: Vocal cord paralysis (VCP) is one of the postoperative complications after radical esophagectomy. VCP may also lead to serious morbidities such as respiratory distress and aspiration pneumonia. Therefore, an early diagnosis of VCP is meaningful in the postoperative management of patients undergoing esophagectomy. We evaluated a new practical method for diagnosing postoperative VCP. Methods: The laryngeal assessment of 30 patients was performed, and the presence of VCP was inferred while the following 15 patients by endoscopy before extubation after performing consecutive radical esophagectomy in 45 esophageal cancer patients. The vocal cord mobility, including adduction and abduction, were assessed by inserting the tip of a transnasal endoscope near the vocal cord in the awake patients with orotracheal intubation on the first postoperative day. The presence of VCP was reevaluated after extubation. Results: Eleven of the 30 patients assessed after radical esophagectomy had unilateral VCP and one patient had bilateral VCP. The abduction findings were useful for assessing VCP and the sensitivity, specificity, positive and negative predictive values and accuracy were 97.9%, 100%, 100%, 92.9% and 98.3%, respectively. The results of the following 15 patients were closely similar. Conclusions: The VCP during orotracheal intubation is assessable by transnasal endoscopy.

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Connective tissue attachment to a mesh structure incorporated on the surface of oral implants and extra-oral endosseous craniofacial implants (EOECI) was investigated. Two types of implants were prepared: TI and TI-Mesh. TI was composed of an upper and a lower component, both comprised of a titanium cylinder, which could be connected using a titanium screw. The composition of the TIMesh was similar, but the lower cylinder had a lateral groove that was covered with a titanium mesh. In animal experiments performed using rat calvaria, the lower component was first implanted and was left submerged for 3 weeks, then the upper component was mounted percutaneously. After an additional 2 weeks, each implant and the surrounding tissues were harvested and evaluated. Histological observations revealed collagen fibers originating from surrounding hypodermal tissues anchored to the mesh structures of the TI-Mesh whereas no such collagen fibers were observed around TI. Significantly greater values of the attachment strength, the thickness of the dermal tissue, the thickness of hypodermal tissue, and the attachment lengths were observed in TI-Mesh than those of TI. Thus connective tissue attachment with collagen fibers anchored to the mesh was achieved by incorporating mesh structures into the percutaneously placed implants.

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Although artificial vessels are available for large diameter arteries, there are no artificial vessels for small diameter arteries of < 4 mm. We created a decellularized vascular scaffold (length, 10 mm; outer diameter, 1.5 mm; inner diameter, 1.3 mm) from rat abdominal arteries. We measured the biomechanical characteristics of the scaffolds, implanted them to defects made in rat carotid arteries, and evaluated their patency and the endothelial cell linings. Silastic grafts were implanted as controls. The decellularized scaffolds demonstrated similar mechanical characteristics to normal arteries. All of the control grafts were occluded. Fibroblast-like cells were discovered in the thrombus, and fibrous organization was apparent. In contrast, patency of the grafts in 10 of 12 animals was observed 4 weeks after implantation. The internal cavity of the patent scaffold was completely lined by endotheliallike cells. Thus, the possibility of small artery reconstruction using decellularized scaffolds was demonstrated.

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