RESUMO
PURPOSE: To evaluate the effectiveness of tooth extraction and non-extraction orthodontic treatment on frontal smiling esthetics. METHODS: A literature research was performed using Wanfang database, Chinese Biological Literature database, China National Knowledge Infrastructure, Chinese Scientific Journals Database of VIP, Medline and the Cochrane Library, dating from the establishment of the databases to 31st, August, 2014. Weighted mean difference (WMD) was calculated and meta analysis was performed by Review Manager 5.2. RESULTS: A total of 8 controlled studies were included. The results of meta analysis showed no significant difference between extraction and non-extraction treatment on subjective evaluation of smile esthetics [5.74-7.05 for extraction; 5.53-7.02 for non-extraction; WMD=0.09, 95%CI (-0.28, 0.46), P=0.64], buccal corridor [0.12-0.19 for extraction; 0.11-0.18 for non-extraction; WMD=0.01, 95%CI (-0.00,0.02), P=0.09], maxillary visual arch width [26.3-52.17 mm for extraction; 25.43-52.37 mm for non-extraction; WMD=-0.13, 95%CI (-1.01, 0.75), P=0.77] and smile height [5.7-10.39 mm for extraction; 5.4-9.97 mm for non-extraction; WMD=0.38, 95%CI (-0.27, 1.03), P=0.25]. CONCLUSIONS: Based on the results of this meta analysis, it can't be concluded that extraction treatment could affect the frontal smiling esthetics based on the present clinic evidences. Given the small sample size and the potential heterogeneity, more well-designed prospective studies should be performed in future.
Assuntos
Estética Dentária , Sorriso , Extração Dentária , China , Humanos , Maxila , Estudos ProspectivosRESUMO
To investigate the effects of ischemia/reperfusion on rat submandibular glands without denervation and the possible protective effects of ischemia preconditioning on the glands that experienced ischemia/reperfusion, in-situ ischemia/reperfusion and ischemia preconditioning experimental models of submandibular glands of healthy male Wistar rats were conducted. For ischemia/reperfusion groups, the glands were subjected to 90 min of ischemia without denervation, followed by 1, 12, 24, or 72 h of reperfusion. Ischemia preconditioning was achieved by 3 min of ischemia following 3 min of reperfusion, performed three times before ischemia/reperfusion. Salivary secretion, histological changes, alterations of tight junctions, myeloperoxidase activity, cellular apoptosis, and reactive oxygen species levels were detected. In ischemia/reperfusion glands, rising acute-inflammation responses, reduced tight-junction width, and increased myeloperoxidase activity, reactive oxygen species levels, and apoptotic cell numbers were observed, along with secretory dysfunction, especially at 1 and 12 h post-reperfusion, which seemed to gradually return to normal by 72 h post-reperfusion. In contrast, ischemia preconditioning showed the potential to ameliorate the injury-stress responses caused by ischemia/reperfusion. Our study revealed that ischemia/reperfusion could cause a series of injury-stress responses and ultimately lead to hyposecretion, independently of the parasympathetic nerve supply, which might play an important role in the early-phase dysfunction of the transplanted glands. Ischemia preconditioning could protect the involved glands and improve ischemia/reperfusion-induced hyposecretion.