Global distribution of malocclusion traits: A systematic review

Abstract Objective: Considering that the available studies on prevalence of malocclusions are local or national-based, this study aimed to pool data to determine the distribution of malocclusion traits worldwide in mixed and permanent dentitions. Methods: An electronic search was conducted using PubMed, Embase and Google Scholar search engines, to retrieve data on malocclusion prevalence for both mixed and permanent dentitions, up to December 2016. Results: Out of 2,977 retrieved studies, 53 were included. In permanent dentition, the global distributions of Class I, Class II, and Class III malocclusion were 74.7% [31 - 97%], 19.56% [2 - 63%] and 5.93% [1 - 20%], respectively. In mixed dentition, the distributions of these malocclusions were 73% [40 - 96%], 23% [2 - 58%] and 4% [0.7 - 13%]. Regarding vertical malocclusions, the observed deep overbite and open bite were 21.98% and 4.93%, respectively. Posterior crossbite affected 9.39% of the sample. Africans showed the highest prevalence of Class I and open bite in permanent dentition (89% and 8%, respectively), and in mixed dentition (93% and 10%, respectively), while Caucasians showed the highest prevalence of Class II in permanent dentition (23%) and mixed dentition (26%). Class III malocclusion in mixed dentition was highly prevalent among Mongoloids. Conclusion: Worldwide, in mixed and permanent dentitions, Angle Class I malocclusion is more prevalent than Class II, specifically among Africans; the least prevalent was Class III, although higher among Mongoloids in mixed dentition. In vertical dimension, open bite was highest among Mongoloids in mixed dentition. Posterior crossbite was more prevalent in permanent dentition in Europe.

Resumo Objetivo: considerando-se que os estudos disponíveis sobre a prevalência das más oclusões são de base local ou nacional, esse estudo teve como objetivo reunir dados para determinar a distribuição dos tipos de má oclusão em uma escala global, nas dentições permanente e mista. Métodos: foi realizada uma busca eletrônica através das ferramentas de pesquisa do PubMed, Embase e Google Acadêmico, para reunir estudos publicados até dezembro de 2016 sobre a prevalência das más oclusões, tanto na dentição permanente quanto na dentição mista. Resultados: dos 2.977 estudos encontrados, 53 foram analisados. Na dentição permanente, a distribuição mundial das más oclusões de Classe I, II e III foi, respectivamente, de 74,7% [31 - 97%], 19,56% [2 - 63%] e 5,93% [1 - 20%]. Na dentição mista, a distribuição dessas más oclusões foi de 73% [40 - 96%], 23% [2 - 58%] e 4% [0,7 - 13%]. Em relação às más oclusões verticais, observou-se prevalência de 21,98% de sobremordida profunda e 4,93% de mordida aberta. A mordida cruzada posterior afetou 9,39% da amostra. Os africanos mostraram a maior prevalência de Classe I e mordida aberta na dentição permanente (89% e 8%, respectivamente) e na dentição mista (93% e 10% respectivamente), enquanto os caucasianos apresentaram a maior prevalência de Classe II na dentição permanente (23%) e na dentição mista (26%). A má oclusão de Classe III na dentição mista foi mais prevalente entre xantodermas. Conclusão: mundialmente, nas dentições mista e permanente, as más oclusões de Classe I de Angle são mais prevalentes do que as de Classe II, especificamente entre os africanos; a menos prevalente foi a Classe III, ainda que mais prevalente entre os xantodermas na dentição mista. Na dimensão vertical, as mordidas abertas foram mais prevalentes entre xantodermas na dentição mista. A mordida cruzada posterior apresentou maior prevalência na dentição permanente na Europa.

Prevalence of Hepatitis B Virus Infection among Egyptian Pregnant Women - A Single Center Study.

Background: Hepatitis B virus (HBV) infection still has a relatively high incidence and prevalence worldwide. In the post-vaccination era in developing countries, perinatal vertical transmission remains the most common mode of transmission. Prevention of mother-to-child transmission requires screening for HBV surface antigen (HBsAg) in pregnant women to identify which newborns that must be immunized. Aim: This study aimed to evaluate the prevalence of HBV infection among pregnant mothers who were attending outpatient clinic of the Obstetric Department, and Social and Preventive Medicine Center at Cairo University Hospital Campus, for routine antenatal care. Methods: A cross sectional study included 2,000 pregnant women. A rapid screening test for HBV “One Step HBsAg Rapid Test” was done for all women and all HBsAg-positive cases were confirmed by ELISA for HBsAg. A structured questionnaire for risk factors for HBV acquisition was filled for every pregnant mother positive for HBsAg and a control group of HBsAg negative mothers. Results: Out of 2,000 pregnant women, 35 (1.75%) were positive by the rapid test, out of whom 32/35 cases (91.43) were confirmed to be positive by the confirmatory test representing 1.6% of the study population. Family history of HBV, previous intravenous (IV) injections, medical clinic attendance, hospital admission, and surgeries were the risk factors for acquiring HBV infection (P-value=0.001, 0.003, 0.002, 0.000, and 0.011, respectively). Conclusion: HBV infection is prevalent among pregnant mothers attending our outpatient services. Therefore we recommend screening for HBV in all Egyptian pregnant mothers to prevent neonatal infection by immunoprophylaxis.

Expression of vascular endothelial growth factor and its receptors FLT-1 and KDR in acute leukemia: Clinical relevance and future prospects

Vascular endothelial growth factor [VEGF] and its receptors may play an important role in the pathophysiology of hematopoietic malignancies and the progression of leukemia. The present work aimed to study the expression of VEGF and its receptors namely FLT-1 [VEGFR-1] and KDR/FLK-1 [VEGFR-2] on the transcriptional level in fresh leukemic blast cells isolated from newly diagnosed AML and ALL patients by RT-PCR. The present study demonstrated that acute leukemia whether myeloblastic or lymphoblastic express VEGF and to less extent express its receptors namely FLT-1 and KDR. This may result in the generation of autocrine loop that may support leukemic cell survival and proliferation. On the contrary, to the lack of expression in normal bone marrow samples, VEGF, FLT-1 and KDR were expressed in considerable percentage of the studied AML and ALL patients. There was no significant relationship between the expression of VEGF or its receptors and patients' clinical or laboratory findings. Expression of VEGF and/or KDR receptors was associated with unfavorable treatment outcome and they were associated with risk of treatment failure. This data show that VEGF, FLT-1 and KDR may have clinical relevance and raise the possibility of using angiogenesis inhibitors as a novel therapeutic strategy in acute leukemia. By developing treatment strategies that target both the stromal and tumor compartments, drug resistance may be overcome, and the effect on therapeutic outcome enhanced