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991.
992.
BACKGROUND: Chronic infection and inflammation, including periodontitis, are linked to an increased risk for atherosclerosis. To investigate the possible adverse effects of periodontitis in continuous ambulatory peritoneal dialysis (CAPD) patients, we compared periodontal severity with inflammation and malnutrition, which are associated with poor atherosclerotic outcome in CAPD patients. METHODS: A total of 110 CAPD patients were included in this study to evaluate their clinical periodontal status by using the plaque index, gingival index, and periodontal disease index. Values for nutritional and inflammatory markers and atherosclerotic risk factors were included for analysis with the periodontal index. Analysis of variance, post hoc Tukey's honestly significant difference, univariate and multivariate linear regression analysis, Pearson correlation analysis, and chi2 analysis were used in the evaluation of the data. RESULTS: Poor oral health status was exhibited by 85.5% of our CAPD patients with periodontal disease. We found that age and longer dialysis duration were associated with the severity of periodontitis. Parameters of malnutrition and inflammation and atherosclerotic risk factors also were associated with poor periodontal status. We carried out multiple regression analysis and found that age, albumin level, and duration of dialysis were associated independently with the severity of periodontitis in CAPD patients. A higher percentage of patients in the severe periodontitis group had malnutrition (chi2 = 59.4; P < 0.001), inflammation (chi2 = 60; P < 0.001), and atherosclerosis (chi2 = 65.6; P < 0.001). CONCLUSIONS: Periodontal health is poor in CAPD patients and correlates with markers of malnutrition, inflammation, and atherosclerosis. The diagnosis and treatment of periodontal diseases require better awareness.  相似文献   
993.

Introduction  

Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. It is one of the leading causes of death. Tobacco and alcohol consumption appears to be the major determinants of oral cancer.  相似文献   
994.
This review summarises all head and neck oncology and related papers published in the British Journal of Oral and Maxillofacial Surgery (BJOMS) during the period 2009-2010. A similar review, covering the years 2007-2008 was published in the Journal in 2009 and was well received by readers, as evidenced by the high number of downloads from the BJOMS website. In this article, we include all head and neck oncology-related articles published in the print version of the journal during 2009/10 and concentrate on summarising the full length article papers. Compared to the previous 2-year period, there has been a 25% increase in number of articles published in this sub-specialty.  相似文献   
995.

Objectives

The lack of durability in resin-dentine bonds led to the use of chlorhexidine as MMP-inhibitor to prevent the degradation of hybrid layers. Biomimetic remineralisation is a concept-proven approach in preventing the degradation of resin-dentine bonds. The purpose of this study is to examine the integrity of aged resin-dentine interfaces created with a nanofiller-containing etch-and-rinse adhesive after the application of these two approaches.

Methods

The more established MMP-inhibition approach was examined using a parallel in vivo and in vitro ageing design to facilitate comparison with the biomimetic remineralisation approach using an in vitro ageing design. Specimens bonded without chlorhexidine exhibited extensive degradation of the hybrid layer after 12 months of in vivo ageing.

Results

Dissolution of nanofillers could be seen within a water-rich zone within the adhesive layer. Although specimens bonded with chlorhexidine exhibited intact hybrid layers, water-rich regions remained in those hybrid layers and degradation of nanofillers occurred within the adhesive layer. Specimens subjected to in vitro biomimetic remineralisation followed by in vitro ageing demonstrated intrafibrillar collagen remineralisation within hybrid layers and deposition of mineral nanocrystals in nanovoids within the adhesive.

Conclusions

The impact was realized by understanding the lack of an inherent mechanism to remove water from resin-dentine interfaces as the critical barrier to progress in bonding with the etch-and-rinse technique. The experimental biomimetic remineralisation strategy offers a creative solution for incorporating a progressive hydration mechanism to achieve this goal, which warrants its translation into a clinically applicable technique.  相似文献   
996.

Objectives

The aim of this work was to investigate the effect of high irradiance curing on resultant degree of conversion of ‘flowable’ resin composites and their counterpart higher viscosity paste materials.

Methods

Five commercial flowable materials (Venus; Heraeus Kulzer, Synergy D6; Coltene, Premise; Kerr, Grandio; Voco and Gradia; GC Corp) and their counterpart higher viscosity restorative versions were tested. Specimens were cured with a halogen Swiss Master Light (EMS, Switzerland) using five different curing protocols with similar radiant exposure (18 J/cm2): 400 mW/cm2 for 45 s, 900 mW/cm2 for 20 s, 1500 mW/cm2 for 12 s, 2000 mW/cm2 for 9 s and 3000 mW/cm2 for 6 s. Degree of conversion (DC) was measured in real time by Fourier transform near infrared spectroscopy (FT-NIRS).

Results

Three- and subsequent two way ANOVA testing revealed significant differences (p ≤ 0.02) with respect to “composite type” and “cure protocol” for DC for all 5 product comparisons. Supplementary one-way ANOVA also revealed significant differences between curing protocols (p < 0.05). The majority of higher viscosity resin composite paste materials exhibited similar DC regardless of curing protocol. However, a significant decrease in DC for specimens cured at 3000 mW/cm2 for 6 s compared with 400 mW/cm2 for 45 s was observed for the flowable materials, Grandio (41 ± 0.36 and 62 ± 1.15%, respectively) and Venus (44 ± 0.44 and 67 ± 0.44%, respectively). Conversely, other flowable materials exhibited little or no significant differences between curing modes. Generally, a higher degree of conversion was observed for flowables compared with their more viscous counterpart, except at high irradiance for those materials where a reciprocal relationship with exposure time was not observed.

Conclusions

The validity of exposure reciprocity law and final degree of conversion depends on several factors, amongst which resin viscosity and filler content were important. Practitioners should be aware of the importance of resin composite constituents and irradiation protocols. Information on material composition and appropriate radiation sources by manufacturers may assist practitioners with the selection of appropriate curing protocols for specific material/light curing unit combinations with the aim of reducing the incidence of under-cured restorations and the clinical impact thereof.  相似文献   
997.
The following case report describes the management of a 6-year-old male patient in early mixed dentition with a mesial step molar relation, an anterior reverse overjet, and skeletal Class III due to a slightly deficient maxilla. The treatment plan included protraction of the maxilla by a reverse pull Petit type facemask for 10 months followed by 15 months of active retention by a Frankel III appliance.  相似文献   
998.
Temporomandibular joint ankylosis is one of the most significant disorders of the stomatognathic system because it causes pain associated with severe functional limitations, such as difficulty in chewing and psychological and clinical problems due to poor oral hygiene. These disorders are quite significant in children, since the treatment is even more complex due to the fact that the condylar region is a site of active growth. The earlier the diagnosis is established, the better the treatment prognosis. Ankylosis can be treated by interposition arthroplasty of the temporalis muscle fascia in conjunction with ipsilateral coronoidectomy. The purpose of the present study was to report a clinical case of temporomandibular joint ankylosis in a pediatric patient treated by interposition arthroplasty of the temporalis muscle fascia associated with coronoidectomy.  相似文献   
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