Maintaining Continuity of Self as Perceived by People in the Early Stages of Dementia: A Qualitative Study.

AIM: The purpose of this study is to shed light on the sense of self that occurs among those who have been diagnosed with the early stages of dementia, where the individual attempts to maintain continuity within their world. METHOD: The research was conducted using qualitative induction research methods and data were collected using semi-structured interview methods. The data were reported according to COnsolidated criteria for REporting Qualitative research (COREQ). RESULTS: The diagnosis was Alzheimer's disease for all participants. Of the 15 participants, 6 were male and 9 female. The average age was 69.9 years. For those with the early stages of dementia, a sense of self that attempts to maintain continuity for the world in which they live is made up of the following: "living in the present while connecting to the past," "relying on those that help to connect and fill in the gaps between the past, present, and very near future," and "living daily life in one's own world where past and present are connected." CONCLUSION: By understanding the sense of self that those who are diagnosed with the early stages of dementia experience while trying to maintain continuity within their world, one is able to get closer to their world and it is hoped that this may provide hints as to how to offer support in the future.

Estimation of periodontal pocket surface area in small to medium dogs: a proof-of-concept study.

BACKGROUND: Periodontal disease is the most common dental disease in dogs. Although the systemic effects of periodontal disease have not been clarified in veterinary science, it is necessary to evaluate the effects of periodontal disease in clinical trials in the future. There have been a few clinical attempts made, however, to assess the severity of periodontal inflammation and its impact on the systemic health of dogs. Meanwhile, in the field of dentistry for humans, the periodontal inflamed surface area (PISA) and periodontal epithelial surface area (PESA) have been used to quantitatively assess the degree of periodontal disease affecting a single tooth as well as the overall extent of periodontitis. Recent studies have also suggested the use of these assessments to examine the relationship between periodontal inflammation and systemic health. RESULTS: The estimation formula for a dog's periodontal pocket surface area (PPSA), an alternative to PISA and PESA in humans, was established using body weight and periodontal pocket depth. Actual values were measured using extracted teeth from various dog breeds and sizes (2.3-25.0 kg of body weight) to obtain universal regression equations for PPSA. Altogether, 625 teeth from 73 dogs of 16 breeds were extracted and subsequently analyzed for morphological information. PPSA was measured in 61 dogs of 10 breeds with periodontal disease using the established estimation formulas, and the correlation between PPSA and preoperative blood chemistry data was analyzed accordingly. A strong correlation was found between PPSA and serum globulin (r = 0.71) while moderate correlations were found for C-reactive protein (r = 0.54) and serum albumin (r = -0.51). CONCLUSIONS: Estimation formulas using body weight and the 6-point probing depth were established for determining PPSA. Direct correlations between PPSA and several blood test results were observed in the study sample. Taken together, these results suggest that PPSA could be useful for evaluating the effects of periodontitis on systemic conditions in dogs.

Evaluation of the simulator with automatic irrigation control system designed for countermeasures of internal contamination in dental unit water lines.

The prevention of nosocomial infections is an imperative task. The dental chair unit (DCU) is an indispensable device used in dental treatment. However, it is known that the dental unit water line (DUWL) can become contaminated with biofilm, consisting mainly of heterotrophic bacteria (HB). Recently, the International Organization for Standardization specified the methods for testing DUWL contamination management. On these grounds, a simulator reproducing DUWL was prepared to standardize the examination method of the DUWL contamination. OBJECTIVES: To evaluate the reproducibility of the DUWL simulator, monitor the DUWL contamination states, and test the efficacy of a commercial decontaminant for DUWL. METHODS: The DUWL simulator was assembled by a DCU manufacturing company. The simulator's DUWL was filled with tap water (TW), and left for approximately one year. Neutral electrolyzed water (NEW) was used as a decontaminant for DUWL. Both TW and NEW were passed through DUWL in a timely manner simulating daily dental treatment. Water was sampled from the air turbine hand piece weekly for 4 weeks and used for HB culture. Contamination status was evaluated by measuring bacterial adenosine triphosphate release and by culturing on Reasoner's 2A medium. RESULTS: The DUWL released contaminated water had a bacterial count of over 6 × 104 cfu/mL. After passing NEW through DUWL for 1 week, the count drastically decreased to its basal level and remained steady for 4 weeks. However, TW showed no effect on DUWL decontamination throughout the examination periods. CONCLUSIONS: The DUWL simulator could be useful to examine the efficacy of the decontaminant for DUWL and development of new methods in DUWL contamination management.

Acceleration of bone regeneration of horizontal bone defect in rats using collagen-binding basic fibroblast growth factor combined with collagen scaffolds.

BACKGROUND: Basic fibroblast growth factor (bFGF) has been applied for periodontal regeneration. However, the application depends on bone defect morphology because bFGF diffuses rapidly from defect sites. In a previous study, collagen-binding bFGF (CB-bFGF) has been shown to enhance bone formation by collagen-anchoring in the orthopedic field. The aim of this study is to demonstrate the efficacy of CB-bFGF with collagen scaffolds in bone regeneration of horizontal bone defect. METHODS: Cell proliferation activity and collagen binding activity of CB-bFGF was confirmed by WST-8 assay and collagen binding assay, respectively. The retention of CB-bFGF in the collagen sheet (CS) was measured by fluorescence imaging. The rat horizontal alveolar bone defect model was employed to investigate the efficacy of CB-bFGF with collagen powder (CP). After 4 and 8 weeks, the regenerative efficacy was evaluated by microcomputed tomography, histological, and immunohistochemical analyses. RESULTS: CB-bFGF had a comparable proliferation activity to bFGF and a collagen binding activity. CB-bFGF was retained in CS longer than bFGF. At 8 weeks postoperation, bone volume, bone mineral content, and new bone area in CB-bFGF/CP group were significantly increased compared with those in other groups. Furthermore, epithelial downgrowth was significantly suppressed in CB-bFGF/CP group. At 4 weeks, the numbers of osteocalcin, proliferating cell nuclear antigen, and osteopontin-positive cells at the regeneration site in CB-bFGF/CP group were greater than those in other groups. CONCLUSIONS: CB-bFGF/CP effectively promoted bone regeneration of horizontal bone defect possibly by sustained release of bFGF. The potential of CB-bFGF composite material for improved periodontal regeneration in vertical axis was shown.

Mesenchymal stem cell-induced cranial suture-like gap in rats.

BACKGROUND: Mesenchymal stem cells are used in the reconstruction of many organs and tissues. However, there are no data regarding cranial suture regeneration using mesenchymal stem cells. Because cranial sutures are important for cranial bone growth, the authors examined whether mesenchymal stem cells could aid with suture reformation in adolescent rats. METHODS: Mesenchymal stem cells were isolated from bone marrow of rat femora. Twenty 4-week-old Fischer 344 male rats received sagittal suture and bone defects with a diameter of 6.0 mm, and mesenchymal stem cells were grafted with membranes. Twenty control rats underwent empty membrane transplantation. The mesenchymal stem cell and control groups were killed at 4, 8, 16, and 24 weeks after surgery. The parietal bones, including the sagittal suture, were observed under a light microscope. Bone structures were measured on digitized photomicrographs captured in a computer. For each sample, bone and suture regeneration were observed by dorsoventral cephalograms. RESULTS: In 4- and 8-week control and mesenchymal stem cell groups, a small volume of new bone formation was observed. In the 16- and 24-week mesenchymal stem cell groups, a large amount of new bone formation and a suture-like gap were identified. In contrast, only a small volume of new bone formation along with craniosynostosis was detected in the 24-week control group. CONCLUSION: These results suggest that mesenchymal stem cell grafting may be a novel option for cranioplasty, not only repairing bone tissue but also resulting in suture-like gap formation, which may advance cranial bone growth.