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101.

PURPOSE

Occlusal splints are commonly used to prevent tooth wear caused by bruxism. However, the effects of splints on occlusion are still unclear. Although it is rarely alluded in literature, splints can provoke severe occlusal alterations and other complications. This study was aimed to identify differences in the responses of individuals with bruxism and healthy individuals to a full-arch maxillary stabilization splint in terms of occlusal changes.

MATERIALS AND METHODS

Occlusal contacts in 20 (5 male, 15 female) bruxism patients and 20 (5 male, 15 female) controls with normal occlusion were evaluated before and after occlusal splint therapy. T-Scan III, a computerized occlusal analysis system, was used to simultaneously measure occlusion and disclusion times as well as left-right and anterior-posterior contact distributions before splint therapy and 3 months after therapy. Wilcoxon and Mann-Whitney U tests were used for statistical analyses (α=.05).

RESULTS

No differences were found in the posterior contact of bruxism patients before and after stabilization splint treatment. However, differences in posterior contact were observed between bruxists and normal individuals prior to treatment, and this difference disappeared following treatment.

CONCLUSION

The results of this study showed the use of a stabilization splint may not have an effect on occlusion. However, the area of posterior occlusal contact among bruxists was found to be greater than that of normal individuals. According to this study, the clinical use of splints may be harmless.  相似文献   
102.
目的 分析新型冠状病毒(新冠病毒)感染者航班同乘人员新冠病毒核酸阳性检出情况,为有效确定风险人员排查范围提供依据。方法 回顾性收集我国2020年4月1日至2022年4月30日本土新冠病毒感染者航班同乘人员信息,采用χ2检验分析比较指示病例发病前不同时间、不同座位距离和不同新冠病毒变异株流行期的同乘人员核酸阳性检出率。结果 研究期间,新冠病毒感染者共涉及370架次航班和23 548名同乘人员,累计判定指示病例433名。指示病例的同乘人员中,核酸检测阳性人员72名,其中,与指示病例同行人员57名,非同行人员15名。对15名非同行的阳性同乘人员进一步分析显示,86.67%在指示病例诊断后3 d内发病或检测阳性,乘机时间均在指示病例发病前4 d内,指示病例前后三排内的阳性检出率为0.15%(95%CI:0.08%~0.27%),显著高于前后三排外的阳性检出率[0.04%(95%CI:0.02%~0.10%),P=0.007],前后三排内各排的阳性检出率差异无统计学意义(P=0.577)。不同类型变异株流行期间,非同行的同乘人员阳性检出率差异无统计学意义(P=0.565)。Omicron变异株流行期中,非同行人员阳性检出集中在指示病例发病前3 d内。结论 指示病例航班同乘人员的风险排查时间可设定为指示病例发病前4 d内。指示病例前后三排内的同乘人员应作为优先排查人员,并作为密切接触者进行管理,座位距离在指示病例前后三排外的同乘人员可作为一般风险人员进行排查和管理。  相似文献   
103.
Quinacrine (QC) is an anti-inflammatory drug that has been used for the treatment of malaria and rheumatoid diseases. The mechanism(s) underlying the anti-inflammatory activity of QC remains poorly understood. We recently reported the QC-mediated inhibition of the NF-kappaB pathway using an in vitro model. To test this potential mechanism in vivo, we used the contact hypersensitivity response (CHS) to chemical allergen sensitization and challenge in mice as a model of skin inflammation. The results indicated that QC treatment inhibited NF-kappaB activation in the skin during allergen sensitization. This inhibition was reflected by decreased mRNA expression and protein production of the NF-kappaB-dependent cytokines TNF-alpha and IL-1beta and the chemokine CCL21 in the skin. The decreases in these cytokines resulted in reduced migration of allergen-presenting dendritic cells from the skin into skin-draining lymph nodes and markedly decreased activation of effector CD8+ T cells for the CHS response to allergen challenge (inhibitory concentration 50% or IC50 was 55 mg/kg). These findings reveal a previously unrecognized mechanism of QC-mediated inhibition of inflammation.  相似文献   
104.
Iron-oxide nanoparticles (NPs) generated by environmental events are likely to represent health problems. α-Fe2O3 NPs were synthesized, characterized and tested in a model for toxicity utilizing human whole blood without added anticoagulant. MALDI-TOF of the corona was performed and activation markers for plasma cascade systems (complement, contact and coagulation systems), platelet consumption and release of growth factors, MPO, and chemokine/cytokines from blood cells were analyzed. The coronas formed on the pristine α-Fe2O3 NPs contained contact system proteins and they induced massive activation of the contact (kinin/kallikrein) system, as well as thrombin generation, platelet activation, and release of two pro-angiogeneic growth factors: platelet-derived growth factor and vascular endothelial growth factor, whereas complement activation was unaffected. The α-Fe2O3 NPs exhibited a noticeable toxicity, with kinin/kallikrein activation, which may be associated with hypotension and long-term angiogenesis in vivo, with implications for cancer, arteriosclerosis and pulmonary disease.  相似文献   
105.
106.
Purpose:The aim of this study is to study the association between Nocturnal Intraocular Pressure (IOP) related Peak recorded by a Contact Lens Sensor (CLS) and glaucoma progression in treated glaucomatous eyes.Methods:Institutional study in which forty glaucoma patients were recruited from glaucoma clinic. A total of 19 patients were labeled as progressors on current anti-glaucoma treatment despite controlled day time IOP whereas twenty one patients were clinically stable showing no progression. Worse eye of each patient was selected for placement of CLS. The timing of the highest signal (IOP related peak) was noted in 24 hour CLS graph and if it fell within the time frame of 11 pm to 5 am, it was labeled as ''nocturnal IOP related peak''.Results:Progressors were found to be significantly more prone to night spike than Non Progressors (χ2 = 6.812; n = 40; P = 0.009), thus, showing a definite association between the two. Association between Nocturnal IOP related peak and various other variables like age, gender, mean daytime IOP and systemic illness was studied. A positive correlation was established between female gender and Nocturnal IOP related spike with a significantly higher proportion of females showing night spike than their male counterparts (χ2 = 5.763; n = 40; P = 0.016). Other parameters did not show any significant relationship with Nocturnal IOP related spike.Conclusion:Dynamic 24 hour recording by CLS is beneficial in detecting nocturnal IOP-related peak, and thus, can potentially improve the clinical care of glaucoma patients, especially those showing progression.  相似文献   
107.
目的:回顾分析双手微小切口超声乳化白内障吸除术的临床疗效。方法:对46例(46眼)老年性白内障患者采用双手微小切口超声乳化白内障吸除术进行治疗,观察术中超声波乳化时间,手术并发症、术后视力及角膜内皮细胞密度的变化。结果:术中超声波乳化时间为28~80s,平均为48s。术后1周最佳矫正视力:4.4~4.9者18眼,4.8以上者共28眼。术中末见明显并发症,术后3服角膜轻度水肿,治疗后消失。5眼术后3个月出现后发性白内障。结论:双手微小切口超声乳化白内障吸除术是一种操作安全、可靠、疗效好的白内障手术方式,对硬核性白内障尤其有效。  相似文献   
108.
109.
BackgroundOptimal management of palmar hand burns in children is controversial. We aimed to compare function and aesthetics of retroauricular full thickness skin grafts (FTSG) to plantar glabrous split thickness skin grafts (STSG).Methods32 palmar grafts in paediatric burn patients were analysed: 19 retroauricular FTSG (group 1) and 13 thick plantar glabrous STSG (group 2). The latter were harvested at a thickness of 0.5 mm. The resulting plantar donor defects were covered with a STSG from the scalp, a sequential surgical technique we termed the “Zurich move”. Clinical examination, Cutometer and Colorimeter assessment and validated patient and observer questionnaires were used. Donor site complications and subjective complaints were recorded.ResultsColorimeter results were superior in group 2 with an erythema score of 5.73 ± 2.64 (group 1) versus 2.33 ± 1.97 (group 2, p < 0.001) and a pigmentation score of 9.82 ± 5.42 (group 1) and 1.89 ± 1.92 (group 2, p < 0.001). Observers` scar evaluation using VSS and POSAS showed significantly superior results in group 2 for almost all items. Conversely, group 1 grafts were less stiff with mean normalized tissue extension R0 of 0.80 ± 0.21 versus 0.57 ± 0.24 in group 2 grafts (p < 0.05). In both groups donor sites complications were rare.ConclusionPlantar glabrous STSG showed superior functional and aesthetic results when compared to FTSG in pediatric palmar hand burns. In addition, the “Zurich Move” is safe and provides uncomplicated donor site healing on the scalp and the foot allowing rapid restoration of full function.  相似文献   
110.
目的探讨翻转课堂教学在角膜塑形术首次戴镜患儿中的应用效果。方法将160例角膜塑形术患儿按时间段分为对照组和干预组各80例,对照组给予常规健康教育,干预组采用翻转课堂教学。比较两组患儿戴镜成功率和满意度。结果干预组患儿戴镜一次成功率、总成功率及满意度评分显著高于对照组(均P0.01)。结论翻转课堂教学能提高角膜塑形术患儿戴镜成功率,提升患儿及其家长的满意度。  相似文献   
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