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61.
During the last decades, an exciting new array of imaging modalities, such as digital imaging, CT, MRI, positron emission tomography, and cone-beam CT (CBCT), has provided astounding new images that continually contribute to the accuracy of diagnostic tasks of the maxillofacial region. The most recent, cone-beam imaging, is gaining rapid acceptance in dentistry because it provides cross-sectional imaging that is often a valuable supplement to intraoral and panoramic radiographs. The information content in such examinations is high and the dose and costs are low. The increasing trend toward the use of CBCT in dental offices may be expected to result in improved diagnosis, but with increased patient dose and health care costs. Using CBCT as a secondary imaging tool helps optimize health-to-risk ratio.  相似文献   
62.
The effect of chewing gum use on in situ enamel lesion remineralization.   总被引:1,自引:0,他引:1  
Two independent cross-over studies investigated the possibility of enhanced early enamel lesion remineralization with the use of chewing gum. The first study involved a sorbitol-containing chewing gum, and the second, which had an identical protocol, tested a sucrose-containing chewing gum. In each study, 12 volunteers wore in situ appliances on which were mounted enamel sections containing artificial caries lesions. Subjects brushed twice daily for two min with a 1100-ppm-F (NaF) dentifrice (control and test) and in the test phase chewed five sticks of gum per day for 20 min after meals and snacks. Microradiographs of the enamel lesions were made at baseline and at the end of the seven-week experimental period. In the sugar-free gum study, the weighted mean total mineral loss (delta z) difference [(wk7-wk0) x (-1)] was 788 vol.% min. x micron for the gum, corresponding to remineralization of 18.2%, vs. the control value of 526 vol.% min. x micron, 12.1% remineralization (p = 0.07). There were no significant differences for the surface-zone (p = 0.20) and lesion-body (p = 0.28) values. In the sucrose-containing gum study, the delta z difference was 743 vol.% min. x micron for the gum, corresponding to a remineralization of 18.3%, vs. the control value of 438 vol.% min. x micron, 10.8% remineralization (p = 0.08). The surface-zone values were not significantly different (p = 0.55). For the lesion body, however, the sucrose-containing gum value of 6.11 vol.% min. was significantly different (p = 0.01) from that of the control (2.81 vol.% min.).  相似文献   
63.
OBJECTIVE: This research systematically evaluated the use of a clinically proven desensitizing dentifrice prior to a bleaching regimen in a randomized, multi-center, parallel group, open label clinical study following Good Clinical Practice guidelines. METHODOLOGY: Fourteen dental offices in West Palm Beach, Florida participated in the study during April/May 2004. Fourteen days prior to bleaching, impressions and oral soft tissue assessments were performed, and patients were randomized to either a KNO3 plus fluoride dentifrice (Sensodyne Fresh Mint), or a standard fluoride dentifrice (Crest Regular), brushing 2x per day. On Day 14, patients returned to the dental office for their custom tray and the dispensation of a bleaching kit (Day White Excel 3; 9.5% hydrogen peroxide and KNO3). This was used daily according to the manufacturer's instructions for 30 minutes, and normal oral hygiene continued to be performed using the assigned toothbrush and dentifrice, brushing 2x per day. At the end of each bleaching day, patients answered diary questions about the occurrence and intensity of sensitivity. At the conclusion of the 14-day bleaching period (Day 28), patients returned to their dental office for re-examination, returning all products and diaries. Within seven days of completing the study, patients answered a telephone patient satisfaction survey. RESULTS: A total of 202 patients in fourteen (14) dental offices completed all aspects of the study and were used for the analysis. The professionally dispensed bleaching product provided an improvement of approximately 4.4 Vita shades, regardless of whether it was used with the KNO3 plus fluoride (Sensodyne) or a standard fluoride (Crest) dentifrice. The patient perception of increased sensitivity caused by the bleaching treatment was low but measurable. In the first week of the bleaching, significantly more patients using the KNO3 plus fluoride dentifrice were free from sensitivity (58%) than the standard fluoride dentifrice group (42%). During the 14-day bleaching treatment period, the KNO3 dentifrice patients experienced significantly more "sensitivity free days" (average = 10.1) compared to the standard fluoride dentifrice group (average = 8.6). CONCLUSION: The use of the KNO3 plus fluoride dentifrice (Sensodyne), two weeks prior to and throughout bleaching, may be a useful adjunct for the management of sensitivity caused by professionally dispensed bleaching products. With the bleaching-induced tooth sensitivity, those patients in the KNO3 plus fluoride toothpaste group were significantly more satisfied with their whitening experience and willing to repeat the bleaching treatment.  相似文献   
64.
65.
Hypophosphatasia (HPP) is a rare inherited disorder characterized by rickets and low circulating concentrations of total alkaline phosphatase (ALP) caused by mutations in ALPL. Severe HPP presents in childhood but milder forms can present in adulthood. The prevalence and clinical features of adult HPP are poorly defined. The aim of this study was to evaluate the prevalence and clinical significance of low serum total alkaline phosphatase (ALP) levels in a clinic-based population of adult osteoporotic patients. We searched for patients with low ALP in a cohort of 3285 patients referred to an osteoporosis clinic over a 10-year period and performed mutation screening of ALPL in those with low ALP (≤40 U/L) on two or more occasions. These individuals were matched with four clinic controls with a normal ALP. We also evaluated the prevalence of low ALP and ALPL mutations in 639 individuals from the general population from the same region. We identified 16/3285 (0.49%) clinic patients with low ALP and 14 (87.5%) had potentially pathogenic variants in ALPL. Eight of these individuals were heterozygous for mutations previously described in HPP and 2 were heterozygous for novel mutations (p.Arg301Trp and p.Tyr101X). These mutations were not found in clinic controls or in the general population. Eight patients with low ALP, including 4 with ALPL mutations, were treated with bisphosphonates for an average of 6.5 years. In these individuals, the rate of fractures during treatment was comparable to that in normal ALP clinic controls who were treated with bisphosphonates. We conclude that heterozygous loss-of-function mutations in ALPL are common in osteoporosis patients with low ALP. Further studies are required to determine how best these individuals should be treated. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.  相似文献   
66.
Radiostereometric analysis (RSA) is the most accurate method of measuring component migration using radiographs but is restricted to use in prospective studies. Ein-Bild-Roentgen-analyze (EBRA)-Cup can be used retrospectively, but its accuracy to measure component migration following revision is unknown. This study aimed to determine the accuracy of EBRA-Cup measurements of uncemented acetabular component migration after revision total hip replacement (THR). The secondary aim was to compare the number of cases identified using EBRA-Cup and RSA as having proximally migrated above and below 1 mm at 2 years postoperatively. EBRA-Cup measurements were performed on plain antero-posterior pelvic radiographs taken at the same time as RSA radiographs in a prospective cohort of 53 hips undergoing acetabular revision. At 2 years, the mean difference between the RSA and EBRA-Cup measurements for 17 components used to treat pelvic discontinuity was 0.90 mm, significantly greater than the mean difference of 0.28 mm for 36 components without discontinuity (P = .0001). The mean difference between the RSA and EBRA-Cup measurements at 2 years for hips that were reconstructed with an acetabular component alone, 0.28 mm, was significantly lower than hips that were reconstructed with an acetabular component in combination with an augment and/or cage, 0.74 mm (P = .0005). In conclusion, EBRA-Cup can accurately measure migration of uncemented acetabular components used at revision THR. The presence of pelvic discontinuity, and addition of augments and cages, significantly influenced the accuracy of EBRA-Cup measurements. EBRA-Cup and RSA had good agreement on classification of components that migrated proximally above or below 1 mm at 2 years, with 100% sensitivity, and 87% specificity.  相似文献   
67.
BACKGROUND: Efficacy and safety of FMX103 1.5% for papulopustular rosacea were previously demonstrated in two 12-week, Phase 3 studies. OBJECTIVE: We sought to evaluate the safety and efficacy of FMX103 1.5% foam for up to 52 weeks of treatment. METHODS: Following the completion of two 12-week, double-blind, vehicle-controlled, Phase 3 studies, subjects were invited to enter a 40-week open-label extension study in which all subjects applied FMX103 1.5% once daily. Efficacy endpoints were the reduction in inflammatory lesions and the rate of IGA treatment success from the double-blind baseline. Safety assessments included adverse events, vital signs, laboratory tests, and facial tolerability signs and symptoms. RESULTS: The favorable safety profile of FMX103 1.5% observed in the double-blind studies was maintained over extended treatment lasting up to one year. There were no serious treatment-related adverse events. Long-term treatment with FMX103 1.5% was associated with a greater than 82-percent reduction in inflammatory lesions from baseline and with over 79 percent of subjects achieving treatment success. At the end of the open-label treatment period, over 82 percent of subjects indicated they were overall “satisfied” or “very satisfied” with FMX103 1.5%. All facial local tolerability symptoms improved through Week 52. LIMITATIONS: Due to the nature of the open-label study, lacking a vehicle-treated control, no statistical comparisons can be made. CONCLUSION: FMX103 1.5% demonstrated a favorable safety and tolerability profile for up to 52 weeks. Long-term efficacy was demonstrated by progressive reductions in inflammatory lesions and increasing IGA treatment success, suggesting that FMX103 1.5% may be a suitable option for the treatment for papulopustular rosacea.  相似文献   
68.
69.

Objectives

To establish: a) feasibility of training GPs in a communication intervention to solicit additional patient concerns early in the consultation, using specific lexical formulations (“do you have ‘any’ vs. ‘some’ other concerns?”) noting the impact on consultation length, and b) whether patients attend with multiple concerns and whether they voiced them in the consultation.

Methods

A mixed-methods three arm RCT feasibility study to assess the feasibility of the communication intervention.

Results

Intervention fidelity was high. GPs can be trained to solicit additional concerns early in the consultation (once patients have presented their first concern). Whilst feasible the particular lexical variation of ‘any’ vs ‘some’ seemed to have no bearing on the number of patient concerns elicited, on consultation length or on patient satisfaction. The level of missing questionnaire data was low, suggesting patients found completion of questionnaires acceptable.

Conclusion

GPs can solicit for additional concerns without increasing consultation length, but the particular wording, specifically ‘any’ vs. ‘some’ may not be as important as the placement of the GP solicitation.

Practice implications

GPs can solicit early for additional concerns and GPs can establish patients’ additional concerns in the opening of the consultation, which can help to plan and prioritise patients multiple concerns.  相似文献   
70.
Assessment of thymic output by measurement of naive T cells is carried out routinely in clinical diagnostic laboratories, predominantly using flow cytometry with a suitable panel of antibodies. Naive T cell measurements can also be made using molecular analyses to quantify T cell receptor excision circle (TRECs) levels in sorted cells from peripheral blood. In this study we have compared TRECs levels retrospectively with CD45RA+CD27+ T cells and also with CD45RA+CD31+ T cells in 134 patient samples at diagnosis or during follow‐up. Both panels provide naive T cell measurements that have a strongly positive correlation with TRECs numbers and are suitable for use with enumerating naive T cell levels in a clinical laboratory.  相似文献   
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