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11.
Langerhans cells (LC) are dendritic cells of the immune system able to capture intraepithelial pathogens and migrate to regional lymph nodes to present them to naive T cells. Up to now immunohistological studies on human gingival LC have been carried out using antibodies against HLA-DR or CD1a molecules. A new marker of LC called Langerin (CD207) and described, among other subcellular localisations, in the Birbeck granules is now available in immunohistochemistry. The purpose of this in situ study was to quantify and to compare Langerin+ versus CD1a+ LC number in order to show differences in the expression of these molecules, if any, and to determine which marker is the most specific. The present study was conducted using nine frozen healthy gingival samples. Double immunofluorescence procedures were performed with an anti-Langerin antibody revealed by FITC and with an anti-CD1a-PE antibody. Mounted slides were analysed by fluorescence microscopy and quantifications were performed on projected slides associated with a grid of 0.015 mm(2). Our results have shown that 1/ the number of CD1a+ LC was significantly increased (P=0.01) when compared with Langerin+ LC 2/ 92% of Langerin+ LC co-expressed CD1a 3/ only 82% of CD1a+ cells co-expressed Langerin 4/ a positive correlation was noted between CD1a+ and Langerin+ LC numbers. The present study has revealed the heterogeneity in the phenotype of gingival LC population and shown that Langerin seems the most specific marker for the study of LC.  相似文献   
12.
Augmentation of the partially edentulous ridge can significantly improve the final prosthodontic rehabilitation. For enhancing soft tissue contours in the anterior region, the subepithelial connective tissue graft is the treatment of choice. The combination of connective tissue grafts with alloplastic bone graft material can optimize the ridge augmentation and reduce post extraction defects. The aim of this clinical report is to describe the use of subepithelial connective tissue in conjunction with an alloplastic bone graft for augmentation of a maxillary anterior ridge prior to prosthetic rehabilitation.  相似文献   
13.
Background: Surgery utilizing an enamel matrix protein derivative (EMD) or guided tissue regeneration (GTR) has been shown to promote periodontal regeneration.
Aim: To evaluate the 10-year results following treatment with EMD, GTR, EMD+GTR, and open flap debridement (OFD).
Material and Methods: Thirty-eight patients out of an initial group of 56 participants were treated with one of the four modalities. Results were evaluated before surgery, at 1 year, and at 10 years. Primary outcome variable was CAL change.
Results: Treatment with EMD yielded a mean CAL gain of 3.4±1.0 mm ( p <0.001) and 2.9±1.4 mm ( p <0.001) at 1 and 10 years, respectively. GTR resulted in a mean CAL gain of 3.2±1.4 ( p <0.001) at 1 year and 2.8±1.2 mm ( p <0.001) at 10 years. Mean CAL gain in the EMD+GTR group was of 3.3±1.1 mm ( p <0.001) and 2.9±1.2 mm ( p <0.001) at 1 and 10 years, respectively. Treatment with OFD demonstrated a mean CAL gain of 2.0±1.2 mm ( p <0.01) at 1 year and 1.8±1.1 mm ( p <0.01) at 10 years. Compared with OFD, the three regenerative treatments resulted in statistically significant ( p <0.05) higher CAL gain, at both 1 and 10 years. The CAL change between 1 and 10 years did not present statistically significant differences in any of the four groups.
Conclusion: The present results indicate that the clinical outcomes obtained with all four approaches can be maintained over a period of 10 years.  相似文献   
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BACKGROUND: The purpose of the present study was to compare the healing of deep intrabony defects following treatment with an enamel matrix protein derivative (EMD) combined with either a natural bone mineral (NBM) or beta-tricalcium phosphate (beta-TCP). METHODS: Twenty-four patients with advanced periodontal disease, each of whom displayed one intrabony defect, were randomly treated with a combination of either EMD + NBM or EMD + beta-TCP. Clinical evaluation was performed at baseline and 1 year following therapy. RESULTS: No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the sites treated with EMD + NBM showed a reduction in mean probing depth (PD) from 7.9 +/- 1.0 mm to 3.2 +/- 0.6 mm and a change in mean clinical attachment level (CAL) from 8.8 +/- 1.1 mm to 4.5 +/- 0.6 mm (P < 0.001). In the group treated with EMD + beta-TCP, the mean PD was reduced from 7.8 +/- 1.2 mm to 3.2 +/- 0.9 mm, and the mean CAL changed from 8.8 +/- 1.2 mm to 4.7 +/- 1.2 mm (P < 0.001). In both groups, all sites gained at least 3 mm of CAL. CAL gains of 4 or 5 mm were measured in the majority of the cases (75%), irrespective of treatment modality. No statistically significant differences in terms of PD reductions and CAL gains were observed between the two groups. CONCLUSION: Within the limits of the present study, both therapies resulted in significant PD reductions and CAL gains 1 year after surgery.  相似文献   
16.
The aim of this double-blind, controlled crossover study was to evaluate the influence of food preservatives on in situ dental biofilm growth. Twenty-four volunteers wore appliances with six specimens each of bovine enamel to build up intra-oral biofilms. During three test cycles, the subjects had to put one half of the appliance twice a day in one of the assigned active solutions (0.1% benzoate, BA; 0.1% sorbate, SA or 0.2% chlorhexidine, CHX) and the other into NaCl. After 5 days, the developed biofilms were stained with two fluorescent dyes to visualise vital (green) and dead bacteria (red). Biofilms were scanned by confocal laser scanning microscopy and biofilm thickness (BT) and bacterial vitality (BV%) were calculated. After a washout period of 7 days, a new test cycle was started. The use of SA, BA and CHX resulted in a significantly reduced BT and BV compared to NaCl (p < 0.001). Differences between SA and BA were not significant (p > 0.05) for both parameters, while CHX showed significantly lower values. Both preservatives showed antibacterial and plaque-inhibiting properties, but not to the extent of CHX. The biofilm model enabled the examination of undisturbed oral biofilm formation influenced by antibacterial components under clinical conditions.  相似文献   
17.
This paper reports the treatment of oral lymphangiomas with carbon dioxide CO? Laser. Lymphangiomas are rare congenital lymphatic malformations. These lesions are most frequently diagnosed during childhood, are most commonly located in the head and neck region, and are extremely rare in the oral cavity. Oral lymphangiomas are of complex treatment due to the difficulty in performing a complete excision. CO? laser is the most often used laser in the oral cavity due to its affinity with water and high absorption by the oral mucosa. Several benefits of the use of CO? laser have been reported for surgical oral procedures. The cases reported herein were biopsy-proven lymphangiomas of the oral cavity. The surgical procedures were carried out under local anesthesia and a focused CO? laser beam (λ10.600 nm, Φ ~2 mm, CW/RSP) was used. At the end of the surgery, the laser beam was used on a defocused mode to promote better hemostasis. Neither sutures nor dressings were used after surgery. No medication and only mouthwashes were prescribed to all patients on the postoperative period. There were no postsurgical complaints from the patients and no relapses of the conditions were observed after follow-up periods of 12 and 18 months. The use of CO? laser was practical, easy to carry out and effective on the treatment of oral lymphangiomas, with no lesion recurrence.  相似文献   
18.
ObjectiveDiane Forsythe and other feminist scholars have long shown how system builders’ tacit assumptions lead to the systematic erasure of certain users from the design process. In spite of this phenomena being known in the health informatics literature for decades, recent research shows how patient portals and electronic patients health records continue to reproduce health inequalities in Western societies. To better understand this discrepancy between scholarly awareness of such inequities and mainstream design, this study unravels the (conceptual) assumptions and practices of designers and others responsible for portal implementation in the Netherlands and how citizens living in vulnerable circumstances are included in this process.Materials and methodsWe conducted semistructured interviews (n = 24) and questionnaires (n = 14) with portal designers, health professionals, and policy advisors.ResultsIn daily design practices, equity is seen as an “end-of-the-pipeline” concern. Respondents identify health care professionals rather than patients as their main users. If patients are included in the design, this generally entails patients in privileged positions. The needs of citizens living in vulnerable circumstances are not prioritized in design processes. Developers legitimize their focus with reference to the innovation-theoretical approach of the Diffusion of Innovations.Discussion and conclusionAlthough feminist scholars have developed important understandings of the exclusion of citizens living in vulnerable circumstances from portal design, other academic efforts have profoundly shaped daily practices of portal development. Diane Forsythe would likely have taken up this discrepancy as a challenge by finding ways to translate these insights into mainstream systems design.  相似文献   
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ABSTRACT

Recognizing the public health professional are critical members of interprofessional teams, the Council on Education for Public Health (CEPH) recently added a required Masters of Public Health (MPH) student competency focused on interprofessional education (IPE). A student-centered approach to the design and evaluation of an emergency preparedness-focused curricular program to meet the interprofessional needs of MPH students was used to meet this expectation at the University of Washington. Curriculum design was informed by two 80-minute listening sessions with MPH students to better understand their current interprofessional educational experiences and needs, and how an emergency preparedness-focused two-hour Interprofessional Active Learning Series (iPALS) session could help them develop interprofessional competency. The resultant iPALS session was assessed with a short, paper-based questionnaire. We found MPH students have an interest in participating in IPE, and that all students who participated in the emergency preparedness-focused iPALS session reported significant increases in their interprofessional and disaster response abilities based on their pre- and post-session evaluations. Student-centered IPE curriculum focused on emergency preparedness can enhance the self-reported ability of students across the health sciences to perform on interprofessional teams while engaging in a topic that has relevance to MPH students.  相似文献   
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