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81.

Objective

To evaluate the association between oral conditions, masticatory performance (MP) and oral health-related quality of life (OHRQoL) in 8–12 year-old children.

Design

150 Brazilian scholars were examined for caries and malocclusions. MP was evaluated based on the ability to comminute an artificial test food followed by the determination of the median particle size (X50) and particle distribution in different-sized sieves (“b”). OHRQoL was measured using the Brazilian versions 8–10 and 11–14 of the child perceptions questionnaire (CPQ), considering the following domains: oral symptoms (OS), functional limitations (FL), emotional well-being (EW) and social well-being (SW). Higher scores indicated worse OHRQoL. Data were submitted to Spearman's correlation test and multiple linear regression analysis.

Results

There were significant positive correlations between the psychosocial and OS domains scores of the CPQ8–10 and the number of decayed and missing teeth, respectively. The number of decayed teeth positively correlated with the number of missing teeth and the CPQ11–14 scores. The number of decayed and missing teeth was significantly associated with higher CPQ8–10 scores. Higher CPQ11–14 overall scores were associated with female gender, higher FL domain scores were associated with the number of missing teeth, and higher X50 values and EW domain scores were associated with female gender and the number of decayed teeth.

Conclusions

A higher number of missing teeth correlated with an inferior MP in older children. Children with a higher number of caries rated their oral health less favourably. Older females and those who broke the test material into smaller sizes were also more likely to report a worse OHRQoL, suggesting that the time allowed to reduce food appears to be a more influential factor on children’ perception of oral health than their ability to break down the test material into smaller sizes. Moreover, the subjectivity of functional domain and artificial nature of chewable test material could have influenced the test sensitivity.  相似文献   
82.
Background: To the best of the authors’ knowledge, a standard protocol for treating peri‐implantitis is not yet established. Methods: A total of 150 titanium disks with smooth or rough surfaces contaminated with microbial biofilm were implanted subcutaneously in rats after undergoing one of three treatments: 1) low‐intensity laser (LIL); 2) antimicrobial photodynamic therapy (aPDT); or 3) toluidine blue O (TBO). Sterile and contaminated disks served as negative (NC) and positive (C) control groups, respectively. After days 7, 28, and 84, tissue inflammation was evaluated microscopically by measuring the density of collagen fibers (degree of fibrosis) and concentration of polymorphonuclear neutrophils. Results: Surface texture did not affect the degree of inflammation, but the area of reactive tissue was significantly greater for rough implants (2.6 ± 3.7 × 106 µm2) than for smooth ones (1.9 ± 2.6 × 106 µm2; P = 0.0377). Group C presented the lowest and group NC presented the highest degree of fibrosis with significance only after day 7; these groups had the highest and lowest scores, respectively, for degree of inflammation. Group C showed the largest area of reactive tissue (9.11 ± 2.10 × 106 µm2), but it was not significantly larger than group LIL (P = 0.3031) and group TBO (P = 0.1333). Group aPDT showed the smallest area (4.34 ± 1.49 × 106 µm2) of reactive tissue among the treatment groups. After day 28, groups LIL, aPDT, TBO, and C resembled group NC in all the studied parameters. Conclusion: Group aPDT showed more favorable results in parameter area of reactive tissue than the other methods after day 7, but over longer time periods all methods produced outcomes equivalent to sterile implants.  相似文献   
83.
Objective: To assess sleep bruxism prevalence and its association with circadian preference and sleep-related characteristics among dental students.

Methods: Dental students of the Federal University of Minas Gerais participated in this cross-sectional study. Participants answered a scale assessing individuals' circadian preference, and a questionnaire regarding sleep-related characteristics and behaviors, history of muscle ache in the temporomandibular area, and history of bruxism.

Results: One hundred fifty-two students participated in the study. Sleep bruxism was reported by 11.3%. Most students (63.2%) were classified as intermediary, 34.9% as morningness, and 1.3% as eveningness. Individuals who reported muscle ache in the temporomandibular area in the morning (PR = 3.5; 95% CI = 1.1–11.5) were more likely to be in the group with sleep bruxism.

Conclusion: Muscle ache in the temporomandibular area is an important associated factor with sleep bruxism among dental students. Special attention should be paid to dental students’ circadian preference.  相似文献   
84.

Objective

To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters.

Material and Methods

The frictional forces were evaluated with three different types of metal brackets: a passive self-ligating (SmartClipTM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni TwinTM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni''s post hoc test.

Results

There was a significant difference (p<0.05) in static friction when the three types of brackets were tested with the same wire size. The wire diameter influenced friction only when the brackets had a 10º angulation (p<0.05). The angulation influenced friction (p<0.05) when the brackets were associated with a 0.018" wire.

Conclusion

Brackets with a modified slot design showed intermediate static frictional force values between the conventional and self-ligating brackets tested.  相似文献   
85.
86.
AIM: To investigate the effects of mangiferin on gastrointestinal transit (GIT) in normal and constipated mice, together with the possible mechanism.METHODS: Intragastrically-administered charcoal meal was used to measure GIT in overnight starved Swiss mice. In the first experiments, mangiferin (3 mg/kg, 10 mg/kg, 30 mg/kg, and 100 mg/kg, po) or tegaserod (1 mg/kg, ip) were administered 30 min before the charcoal meal to study their effects on normal transit. In the second series, mangiferin (30 mg/kg) was tested on delayed GIT induced by several different pharmacological agonists (morphine, clonidine, capsaicin) or antagonists (ondansetron, verapamil, and atropine) whereas in the third series, mangiferin (30 mg/kg, 100 mg/kg and 300 mg/kg) or tegaserod (1 mg/kg) were tested on 6 h fecal pellets outputted by freely fed mice. The ratio of wet to dry weight was calculated and used as a marker of fecal water content.RESULTS: Mangiferin administered orally significantly (P < 0.05) accelerated GIT at 30 mg/kg and 100 mg/kg (89% and 93%, respectively), similarly to 5-hydroxytryptamine4 (5-HT4) agonist tegaserod (81%) when compared to vehicle-treated control (63%). Co-administered mangiferin (30 mg/kg) totally reversed the inhibitory effect of opioid agonist morphine, 5-HT3-receptor antagonist ondansetron and transient receptor potential vanilloid-1 receptor agonist capsaicin on GIT, but only to a partial extent with the GIT-delay induced by α2-adrenoceptor agonist clonidine, and calcium antagonist verapamil. However, co-administered atropine completely blocked the stimulant effect of mangiferin on GIT, suggesting the involvement of muscarinic acetylcholine receptor activation. Although mangiferin significantly enhanced the 6 h fecal output at higher doses (245.5 ± 10.43 mg vs 161.9 ± 10.82 mg and 227.1 ± 20.11 mg vs 161.9 ± 10.82 mg of vehicle-treated control, at 30 and 100 mg/kg, P < 0.05, respectively), the effect of tegaserod was more potent (297.4 ± 7.42 mg vs 161.9 ± 10.82 mg of vehicle-treated control, P < 0.05). Unlike tegaserod, which showed an enhanced water content in fecal pellets (59.20% ± 1.09% vs 51.44% ± 1.19% of control, P < 0.05), mangiferin evidenced no such effect, indicating that it has only a motor and not a secretomotor effect.CONCLUSION: Our data indicate the prokinetic action of mangiferin. It can stimulate the normal GIT and also overcome the drug-induced transit delay, via a cholinergic physiological mechanism.  相似文献   
87.
In the present study we used two groups of Candida dubliniensis strains: one containing fluconazole-susceptible clinical isolates and another containing fluconazole-resistant laboratory derivative from the former to examine the changes on susceptibility accompanying the development of resistance to fluconazole. Our findings confirmed the ability of C. dubliniensis isolates to become resistant to fluconazole and indicated that this resistance was crossed with ketoconazole, itraconazole, ravuconazole and terbinafine. We also tested combinations of terbinafine, amphotericin B, itraconazole and voriconazole against both groups of isolates in a checkerboard assay. Surprisingly, most combinations evidenced indifferent interactions, and the best synergism appeared when terbinafine and itraconazole were combined against the fluconazole-resistant group.  相似文献   
88.
AimsTo evaluate the spatio-temporal variables of gait and the isometric muscle strength component of the ankle in patients with peripheral diabetic neuropathy. Also, verify the relationship between these variables and gait parameters.MethodsThis study involved 25 diabetic peripheral neuropathy (DPN) participants (62.4 ± 8.36 years) and 27 age-matched healthy control individuals (64.48 ± 6.21 years). The assessment of the spatio-temporal parameters of gait was performed using an electronic baropodometry treadmill. Prior to the collection data, each participant was instructed to walk on the treadmill in her/his habitual self-selected speed.ResultsDiabetic neuropathy group showed impairment of gait, with a smaller stride and length speed of the cycle, and increased duration of support time. Restricted dorsiflexion mobility and increased plantarflexion mobility were found, with a decrease in muscle strength of the dorsiflexors and plantiflexors. There was a significant relationship between plantiflexor muscle strength and the length and speed of the gait cycle. Also the muscle strengths of the plantiflexors and dorsiflexors, and the range of motion of dorsiflexion were predictors of gait performance.ConclusionsThe ankle, muscle strength and ankle mobility variables could explain changes in gait speed and range of motion in patients with DPN, allowing for the application of preventive strategies.  相似文献   
89.
90.
Arruda AO, Senthamarai Kannan R, Inglehart MR, Rezende CT, Sohn W. Effect of 5% fluoride varnish application on caries among school children in rural Brazil: a randomized controlled trial. Community Dent Oral Epidemiol 2011. © 2011 John Wiley & Sons A/S Abstract – Objectives: To determine the efficacy of 5% sodium fluoride (NaF) varnish application in reducing caries increments in the permanent dentition of rural Brazilian school children over the course of 12 months. Methods: A double‐blind, randomized, placebo‐controlled trial was conducted with 379 children aged 7–14 years who attended three schools in Brazil between January 2006 and December 2007. During this period, each school was visited four times at 6‐month interval for recruitment, dental examinations, and fluoride varnish applications. Recruited children were randomly assigned to either a treatment (5% NaF varnish, n = 198) or a control group (placebo, n = 181). Trained interviewers collected data on oral health habits and sociodemographic characteristics from the children. Information on the child’s diet was collected through a 7‐day food frequency diary. Caries examinations were conducted using the International Caries Detection and Assessment System (ICDAS). The efficacy of fluoride varnish application on caries prevention was reported as a preventive fraction (PF). Crude caries increments of decayed and filled surfaces (DFS) were compared between fluoride varnish and placebo groups. A generalized linear model (GLM) was constructed to test the differences in DFS increments between the groups after accounting for confounding factors. Results: Of the total sample (N = 379), 210 (55.4%) children had completed 12 months of follow‐up including one or two applications of fluoride varnish or placebo. At the baseline examination, the children in the treatment and control groups presented on average 6.2 and 5.6 DFS, respectively (P < 0.001). After 12 months of follow‐up, the children in the varnish group showed significantly lower DFS increments than did children in the control group (10.8 versus 13.3; P < 0.007), with PF of 40% (95% CI: 34.3–45.7%; P < 0.0001). Conclusions: The results of this study suggest that applications of 5% NaF varnish can be recommended as a public health measure for reducing caries incidence in this high‐caries‐risk population.  相似文献   
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