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Objectives: Evaluate the effect on the application of low level laser therapy, in patients that have been previously intervened with a sagittal ramus split osteotomy and present neurosensory impairment due to this surgery, compared with placebo. Study Design: This preliminary study is a randomized clinical trial, with an experimental group (n=17) which received laser light and a control group (n=14), placebo. All participants received laser applications, divided after surgery in days 1, 2, 3, 5, 10, 14, 21 and 28. Neurosensory impairment was evaluated clinically with 5 tests; visual analog scale (VAS) for pain and sensitivity, directional and 2 point discrimination, thermal discrimination, each one of them performed before and after surgery on day 1, and 1, 2 and 6 months. Participants and results evaluator were blinded to intervention. Variables were described with absolute frequencies, percentages and medians. Ordinal and dichotomous variables were compared with Mann Whitney’s and Fisher’s test respectively. Results: Results demonstrate clinical improvement in time, as well as in magnitude of neurosensory return for laser group; VAS for sensitivity reached 5 (normal), 10 participants recovered initial values for 2 point discrimination (62,5%) and 87,5% recovered directional discrimination at 6 months after surgery. General VAS for sensitivity showed 68,75% for laser group, compared with placebo 21,43% (p-value = (0.0095). Left side sensitivity (VAS) showed 3.25 and 4 medians for placebo and laser at 2 months, respectively (p-value = (0.004). Conclusions: Low-level laser therapy was beneficial for this group of patients on recovery of neurosensory impairment of mandibular nerve, compared to a placebo. Key words:Laser Therapy, low-level, LLLP, osteotomy, sagittal split ramus, paresthesia, mandibular nerve.  相似文献   
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Several oil spills due to ruptures in the pipeline oil systems have occurred at the Andean paramo. A sample of this crude oil was mixed with water from a nearby Andean lagoon and the toxicity of the soluble fraction was assessed through lethal and avoidance assays with a locally occurring copepod (Boeckella occidentalis intermedia). The integration of mortality and avoidance aimed at predicting the immediate decline of copepod populations facing an oil leakage. The 24-h median lethal PAH concentration was 42.7 (26.4–91.6) µg L?1. In the 12-h avoidance assay, 30 % avoidance was recorded at the highest PAH concentration (19.4 µg L?1). The mortality at this PAH concentration would be of 25 % and, thus, the population immediate decline would be of 55 %. The inclusion of non-forced exposure testing with the quantification of the avoidance response in environmental risk assessments is, therefore, supported due to underestimation of the lethal assays.  相似文献   
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Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time.  相似文献   
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This publication describes the history of minimal intervention dentistry (MID) for managing dental caries and presents evidence for various carious lesion detection devices, for preventive measures, for restorative and non‐restorative therapies as well as for repairing rather than replacing defective restorations. It is a follow‐up to the FDI World Dental Federation publication on MID, of 2000. The dental profession currently is faced with an enormous task of how to manage the high burden of consequences of the caries process amongst the world population. If it is to manage carious lesion development and its progression, it should move away from the ‘surgical’ care approach and fully embrace the MID approach. The chance for MID to be successful is thought to be increased tremendously if dental caries is not considered an infectious but instead a behavioural disease with a bacterial component. Controlling the two main carious lesion development related behaviours, i.e. intake and frequency of fermentable sugars, to not more than five times daily and removing/disturbing dental plaque from all tooth surfaces using an effective fluoridated toothpaste twice daily, are the ingredients for reducing the burden of dental caries in many communities in the world. FDI's policy of reducing the need for restorative therapy by placing an even greater emphasis on caries prevention than is currently done, is therefore, worth pursuing.  相似文献   
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Lipofilling is a well-established technique in reconstructive plastic surgery. It is used primarily in recontouring of the body and face to correct post-traumatic and congenital defects. The regenerative properties of adipose tissue have allowed the use of the lipofilling technique for the treatment of burn sequelae and irradiated breast to improve tissue quality and elasticity. We report on the case of a patient treated with radiation therapy for a nasopharyngeal carcinoma who presented with severe postradiation dysphagia. The lipofilling technique was successfully used to improve abnormal swallowing. The technical details and functional outcomes are discussed.  相似文献   
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