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41.

Objective

The aim of this study was to compare the effect of two sugar-substituted chewing gums besides toothbrushing on different clinical, microbiological, and biochemical caries- and gingivitis-related variables.

Materials and methods

The study was designed as a double-blind, randomized, controlled trial with three parallel arms. A total of 130 dental students, who volunteered after signing an informed consent, were randomly allocated to receive one of the following interventions: hexitol-sweetened gum containing casein phosphopeptide–amorphous calcium phosphate (CPP-ACP), pentitol-sweetened gum containing no CPP-ACP, and control group with no gum. Subjects within the experimental groups chewed two gum pellets for 20 min three times a day after meals. The daily consumption level of both polyols was 6.0 g. Clinical examinations and salivary samplings were conducted at baseline and after 30 days of gum use. Pre- and post-intervention stimulated whole saliva samples were quantified for calcium/phosphate ionic concentration, total facultative bacterial load, Streptococcus mutans/Lactobacillus spp. counts, and Gram-negative percentage.

Results

A statistically significant reduction in visible plaque score was displayed in the hexitol/CPP-ACP gum group after the intervention when compared with baseline, but the order of the effect was in the same order as the differences between the groups at baseline. A similar tendency was seen in both the pentitol/non-CPP-ACP gum and control groups regarding total salivary facultative bacterial load and S. mutans count, but median values of these parameters were more significantly reduced in the pentitol/non-CPP-ACP gum group in comparison with those of the control group. Alterations of salivary Lactobacillus spp. were demonstrated only in the pentitol/non-CPP-ACP gum group.

Conclusion

Although these findings might indicate that a 30-day protocol of daily chewing of pentitol-sweetened gum containing no CPP-ACP might have some a reducing effect on the salivary levels of facultative bacteria, S. mutans and Lactobacillus spp., there was only a marginal, if any, benefit from the chewing gums under study on some microbiological caries- and gingivitis-related variables.

Clinical relevance

Taking into account that for transferring results into clinically relevant conclusions the findings need to be strong and consistent, adhering to single significant differences appears not appropriate. Hence, the clinical significance of chewing gums as an adjunctive tool for daily oral care remained questionable.  相似文献   
42.

Objective

The aim was to investigate a possible association between the immunoexpression of interleukin (IL)-4 and clinicopathological parameters with the periodontal breakdown observed in gingival pyogenic granuloma (PG).

Materials and methods

Paraffin-embedded samples of gingival PG (n?=?46) were prepared for histological and immunohistochemical assessment. Demographic and clinical parameters were assessed by criteria based on age stratum, gender, smoking habit, evolution course, location, lesion size, macroscopic appearance, predisposing factors, recurrence, and periodontal breakdown. Histological assessment included the appearance of epithelial lining, microvessel density, inflammatory infiltrate density, interstitial fibrosis, and histological arrangement. A staining intensity distribution (SID) score was used to assess IL-4 immunoreactivity. The association between candidate predictor variables and periodontal breakdown was analyzed individually and adjusted for confounding using a bivariate binary logistic regression model.

Results

Mean IL-4 SID values were significantly increased for long-standing and large lesions, presence of periodontal breakdown, high microvessel density, and moderate-to-severe inflammatory infiltrate density. While bivariate and univariate analyses revealed a positive association of the evolution course ≥12 months, lesion size >1 cm, high microvessel density, moderate-to-severe inflammatory infiltrate density, and IL-4 SID score ≥8.04 with periodontal breakdown, after bivariate logistic regression analysis, only the evolution course ≥12 months, moderate-to-severe inflammatory infiltrate density, and IL-4 SID score ≥8.04 remained as robust predictors of periodontal damage. Confounding and interaction effects between candidate predictor variables were also noted.

Conclusion

These findings suggest that while evolution course, inflammatory infiltrate density, and the overexpression of IL-4 may act as predictors of periodontal breakdown in gingival PG, there are mutual confounding and synergistic biological interactive effects with respect to the lesion size and microvessel density in the susceptible host that may be also associated with the bone resorption and tissue destruction.

Clinical relevance

Although the first-line therapy of gingival PG continues to be the surgical excision, this approach poses unwanted complications such as severe mucogingival defects and recurrence. Hence, early diagnosis and detection of these three significant predictor variables as well as timely surgical excision might help prevent the periodontal tissue destruction observed in some of these lesions.  相似文献   
43.

Objectives

This study aimed to develop the Chinese version of the Perceived Barriers to Health Care-seeking Decision (PBHSD-C) and evaluate its psychometric properties in Chinese patients with acute coronary syndromes (ACS).

Background

The assessment of the level of perceived barriers in the care-seeking trajectory of ACS patients is important for the understanding of its impact on pre-hospital delay in seeking care.

Methods

The psychometric properties of PBHSD-C were evaluated among 114 ACS patients in the cardiac unit of two major hospitals in Hong Kong.

Results

The Content Validity Indexes were ranged from .88 to 1. The Cronbach's alpha of the PBHSD-C was .74. The intraclass correlation coefficients of all items were above .80. The convergent validity of the PBHSD-C was also supported.

Conclusion

The PBHSD-C is reliable and valid to be used to assess the level of perceived barriers in the care-seeking of Chinese patients with ACS.  相似文献   
44.
Aligning the acetabular component with the Transverse Acetabular Ligament (TAL) to ensure optimal anteversion has been reported to reduce dislocation rates. However, to our knowledge in vivo measurement of the TAL angle has not yet been reported in a large cohort of normal hips. CT scans of 218 normal hips were analyzed. The TAL and four acetabular rim anteversion angles were measured (superiorly to inferiorly) relative to the anterior pelvic plane. The mean TAL anteversion angle was 20.5° ± 7.0°, and the acetabular rim angles from superior to inferior were 11.0° ± 12.9°, 19.9° ± 8.8°, 20.9° ± 6.2° and 25.1° ± 6.2° respectively. Both the TAL and the acetabular rim were significantly more anteverted in females than in males. The TAL anteversion angle was comparable to the predominant orientation (central rim section) of the native acetabulum while the superior acetabulum was comparatively retroverted and the inferior was relatively more anteverted.  相似文献   
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WIN 51711 (5-[7-[4-(4,5-dihydro-2-oxazolyl)phenoxy]heptyl]-3-methylisoxazole), a new antipicornavirus drug, is a potent inhibitor of human entero- and rhinoviruses at concentrations not inhibitory to HeLa cell growth. In plaque reduction assays, WIN 51711 reduced plaque formation by 9 enteroviruses and 33 rhinoviruses, with MICs of 0.004 to 0.17 and 0.004 to 6.2 micrograms/ml, respectively. Addition of WIN 51711 to infected cells at concentrations of 0.02 to 5.0 micrograms/ml reduced the yield of picornaviruses by 90%. Other RNA viruses (nonpicornaviruses) and DNA viruses were unaffected by the compound.  相似文献   
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