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1.
BMC Oral Health ; 20(1): 43, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32028960

RESUMO

BACKGROUND: Better understanding of the danger zone anatomy in mesial roots (MRs) of mandibular first molars (MFMs) may serve to decrease the risk of mishaps. This study aimed to measure the minimal distal dentine thicknesses of danger zone in MRs of MFMs in a native Chinese population using cone-beam computed tomography (CBCT). METHODS: CBCT images of 1792 MFMs from 898 Chinese patients were analyzed. The minimal distal dentine thicknesses of the mesiobuccal (MB) and mesiolingual (ML) canals below the furcation 1, 2, 3, 4, 5 mm were measured. The association between the minimal distal dentine thicknesses and the root lengths, patient's age and gender, side were assessed. RESULTS: The minimal distal dentine thicknesses of MB and ML canals are located 3 ∼ 4 mm below the furcation for both men and women. There are no differences between MB and ML canals, while the minimal distal dentine thicknesses of MB and ML canals were higher in men than women (P < 0.05), except at 1 and 3 mm of ML canals (P > 0.05). The minimal distal dentine thicknesses of MB and ML canals increased with age in both men and women at each location (P < 0.05). The minimum distal dentine thickness at every location were significantly different between long teeth and short teeth both in men and women (P < 0.05), with short teeth having the smallest mean values. There are no significant differences between two sides (P > 0.05). CONCLUSIONS: The minimal distal dentine thicknesses of MRs in MSMs have close correlation with root length, patient's age and gender.

2.
Head Face Med ; 13(1): 24, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29229002

RESUMO

BACKGROUND: Ectopic mandibular third molar is a rare clinical entity with incompletely known etiology. Here, we sought to delineate its epidemiological, clinical and radiographic characteristics, and therapy by integrating and analyzing the cases treated in our institution together with previously reported cases. METHOD: A new definition and classification for ectopic mandibular third molar was proposed based on its anatomic location on panoramic images. Thirty-eight ectopic mandibular third molars in 37 patients and 51 teeth in 49 patients were identified in our disease registry and from literature (1990-2016), respectively. These cases were further categorized and compared according to our classification protocol. The demographic, clinicopathological and radiographic data were collected and analyzed. RESULTS: These ectopic teeth were categorized into four levels, 33 in level I(upper ramus), 32 in level II (middle ramus), 15 in level III (mandibular angle) and 9 in level IV (mandibular body). The common clinical presentations included pain, swelling and limited mouth opening, although sometimes asymptomatic. Most teeth were associated with pathological lesions. Treatments included clinical monitor and surgical removal by intra- or extraoral approach with favorable outcomes. Clinical presentations and treatment options for these teeth were significantly associated with their ectopic locations as we classified. CONCLUSIONS: Ectopic mandibular third molars are usually found in patients with middle ages and in upper and middle ramus of mandible. Surgery is preferred to remove these ectopic teeth and associated pathologies when possible.


Assuntos
Coristoma/cirurgia , Dente Serotino/cirurgia , Sistema de Registros , Extração Dentária/métodos , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia , Adulto , Coristoma/diagnóstico por imagem , Coristoma/epidemiologia , Feminino , Humanos , Incidência , Masculino , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade , Dente Serotino/diagnóstico por imagem , Radiografia Panorâmica/métodos , Doenças Raras , Estudos Retrospectivos , Medição de Risco , Dente Impactado/epidemiologia , Resultado do Tratamento
3.
J Int Med Res ; 45(2): 830-842, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28351286

RESUMO

Objective To evaluate the root and root canal morphology of the maxillary second molars (MSMs) in a native Chinese population by cone-beam computed tomography. Methods Cone-beam computed tomography images of 2412 MSMs from 1294 Chinese patients were analyzed to determine the number and morphology of the roots, the root canal morphology, the bilateral symmetry, and the correlations of these parameters with sex and age. Results The percentage of fused roots increased with age, while the percentage of fused roots in women was higher than that in men. The percentage of second mesiobuccal (MB2) canals in MSMs with three separate roots was higher in men than women. Patients aged 31 to 40 years showed a higher prevalence of MB2 canals, while those aged ≥51 years showed the lowest prevalence of MB2 canals among both men and women. There was a significant difference in bilateral symmetry of MSMs between men and women. Conclusion Root fusion of MSMs increased with age, while the root canal morphology was more complex in patients of intermediate ages.


Assuntos
Cavidade Pulpar/anatomia & histologia , Maxila/anatomia & histologia , Dente Molar/anatomia & histologia , Raiz Dentária/anatomia & histologia , Adulto , Fatores Etários , Idoso , Grupo com Ancestrais do Continente Asiático , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar/diagnóstico por imagem , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Dente Molar/diagnóstico por imagem , Fatores Sexuais , Raiz Dentária/diagnóstico por imagem
4.
Sci Rep ; 6: 39268, 2016 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-27991572

RESUMO

The present study was aimed to determine the topographic relationship between root apex of the mesially and horizontally impacted mandibular third molar and lingual plate of mandible. The original cone beam computed tomography (CBCT) data of 364 teeth from 223 patients were retrospectively collected and analyzed. The topographic relationship between root apex and lingual plate on cross-sectional CBCT images was classified as non-contact (99), contact (145) and perforation (120). The cross-sectional morphology of lingual plate at the level of root apex was defined as parallel (28), undercut (38), slanted (29) and round (4). The distribution of topographic relationship between root apex and lingual plate significantly associated with gender, impaction depth, root number and lingual plate morphology. Moreover, the average bone thickness of lingual cortex and distance between root apex and the outer surface of lingual plate were 1.02 and 1.39 mm, respectively. Furthermore, multivariate regression analyses identified impaction depth and lingual plate morphology as the risk factors for the contact and perforation subtypes between root apex and lingual plate. Collectively, our findings reveal the topographic proximity of root apex of impacted mandibular third molar to the lingual plate, which might be associated with intraoperative and postoperative complications during tooth extraction.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dente Serotino/fisiologia , Raiz Dentária/fisiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/fisiologia , Pessoa de Meia-Idade , Dente Serotino/diagnóstico por imagem , Análise Multivariada , Estudos Retrospectivos , Raiz Dentária/diagnóstico por imagem , Dente Impactado/diagnóstico por imagem , Adulto Jovem
5.
PLoS One ; 7(11): e51209, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226489

RESUMO

BACKGROUND: Studying the dispersal range of Anopheles sinensis is of major importance for understanding the transition from malaria control to elimination. However, no data are available regarding the dispersal range of An. sinensis in China. The aim of the present study was to study the dispersal range of An. sinensis and provide the scientific basis for the development of effective control measures for malaria elimination in China. METHODOLOGY/PRINCIPAL FINDINGS: Mark-Release-Recapture (MRR) experiments were conducted with 3000 adult wild An. sinensis in 2010 and 3000 newly emerged wild An. sinensis in 2011 in two villages of Yongcheng City in Henan Province. Marked An. sinensis were recaptured daily for ten successive days using light traps. The overall recapture rates were 0.83% (95% CI, 0.50%~1.16%) in 2010 and 1.33% (95% CI, 0.92%~1.74%) in 2011. There was no significant difference in the recapture rates of wild An. sinensis and newly emerged An. sinensis. The majority of An. sinensis were captured due east at study site I compared with most in the west at study site II. Eighty percent and 90% of the marked An. sinensis were recaptured within a radius of 100 m from the release point in study site I and II, respectively, with a maximum dispersal range of 400 m within the period of this study. CONCLUSIONS/SIGNIFICANCE: Our results indicate that local An. sinensis may have limited dispersal ranges. Therefore, control efforts should target breeding and resting sites in proximity of the villages.


Assuntos
Distribuição Animal/fisiologia , Anopheles/fisiologia , Cidades , Métodos Epidemiológicos , Animais , China , Feminino , Fluorescência , Masculino , Conceitos Meteorológicos , Análise de Regressão , População Rural , Especificidade da Espécie , Análise de Sobrevida
6.
BMC Public Health ; 12: 544, 2012 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-22823998

RESUMO

BACKGROUND: In 2003, Plasmodium vivax malaria has re-emerged in central eastern China including Yongcheng prefecture, Henan Province, where no case has been reported for eleven years. Our goals were to detect the space-time distribution pattern of malaria and to determine significant environmental variables contributing to malaria incidence in Yongcheng from 2006 to 2010, thus providing scientific basis for further optimizing current malaria surveillance and control programs. METHODS: This study examined the spatial and temporal heterogeneities in the risk of malaria and the influencing factors on malaria incidence using geographical information system (GIS) and time series analysis. Univariate analysis was conducted to estimate the crude correlations between malaria incidence and environmental variables, such as mosquito abundance and climatic factors. Multivariate analysis was implemented to construct predictive models to explore the principal environmental determinants on malaria epidemic using a Generalized Estimating Equation (GEE) approach. RESULTS: Annual malaria incidence at town-level decreased from the north to south, and monthly incidence at prefecture-level demonstrated a strong seasonal pattern with a peak from July to November. Yearly malaria incidence had a visual spatial association with yearly average temperature. Moreover, the best-fit temporal model (model 2) (QIC = 16.934, P<0.001, R2 = 0.818) indicated that significant factors contributing to malaria incidence were maximum temperature at one month lag, average humidity at one month lag, and malaria incidence of the previous month. CONCLUSIONS: Findings supported the effects of environment factors on malaria incidence and indicated that malaria control targets should vary with intensity of malaria incidence, with more public resource allocated to control the source of infections instead of large scale An. sinensis control when malaria incidence was at a low level, which would benefit for optimizing the malaria surveillance project in China and some other countries with unstable or low malaria transmission.


Assuntos
Malária Vivax/epidemiologia , Animais , Anopheles/parasitologia , China/epidemiologia , Meio Ambiente , Sistemas de Informação Geográfica , Humanos , Incidência , Malária Vivax/etiologia , Plasmodium vivax , Análise Espaço-Temporal , Tempo (Meteorologia)
7.
Parasit Vectors ; 5: 136, 2012 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-22776520

RESUMO

BACKGROUND: Both falciparum and vivax malaria were historically prevalent in China with high incidence. With the control efforts, the annual incidence in the whole country has reduced to 0.0001% except in some areas in the southern borders after 2000. Despite this, the re-emergence or outbreak of malaria was unavoidable in central China during 2005-2007. In order to understand the role of the vector in the transmission of malaria during the outbreak period, the vector capacity of An. sinensis in Huanghuai valley of central China was investigated. FINDINGS: The study was undertaken in two sites, namely Huaiyuan county of Anhui province and Yongcheng county of Henan province. In each county, malaria cases were recorded for recent years, and transmission risk factors for each study village including anti-mosquito facilities and total number of livestock were recorded by visiting each household in the study sites. The specimens of mosquitoes were collected in two villages, and population density and species in each study site were recorded after the identification of different species, and the blood-fed mosquitoes were tested by ring precipitation test. Finally, various indicators were calculated to estimate vector capacity or dynamics, including mosquito biting rate (MBR), human blood index (HBI), and the parous rates (M). Finally, the vector capacity, as an important indicator of malaria transmission to predict the potential recurrence of malaria, was estimated and compared in each study site.About 93.0% of 80 households in Huaiyuan and 89.3% of 192 households in Yongcheng had anti-mosquito facilities. No cattle or pigs were found, only less than 10 sheep were found in each study village. A total of 94 and 107 Anopheles spp. mosquitos were captured in two study sites, respectively, and all of An. sinensis were morphologically identified. It was found that mosquito blood-feeding peak was between 9:00 pm and 12:00 pm. Man biting rate of An. sinensis was 6.0957 and 5.8621 (mosquitoes/people/night) estimated by using half-night human bait trap method and full-capture method, respectively. Human blood indexes (HBI) were 0.6667 (6/9) and 0.6429 (18/28), and man-biting habits were 0.2667 and 0.2572 in two sites, respectively. Therefore, the expectation of infective life and vector capacity of An. sinensis was 0.3649-0.4761 and 0.5502-0.7740, respectively, in Huanhuai valley of central China where the outbreak occurred, which is much higher than that in the previous years without malaria outbreak. CONCLUSIONS: This study suggests that vivax malaria outbreak in Huanhuai valley is highly related to the enhancement in vector capacity of An. sinensis for P. vivax, which is attributed to the local residents' habits and the remarkable drop in the number of large livestock leading to disappearance of traditional biological barriers.


Assuntos
Anopheles/parasitologia , Insetos Vetores , Malária Vivax/epidemiologia , Malária Vivax/transmissão , Plasmodium vivax/fisiologia , Animais , Anopheles/classificação , Surtos de Doenças , Feminino , Interações Hospedeiro-Parasita , Humanos , Incidência , Controle de Mosquitos , Fatores de Risco
8.
Parasit Vectors ; 5: 58, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22444032

RESUMO

BACKGROUND: Characterizing the breeding site of Anopheles sinensis is of major importance for the transition from malaria control to elimination in China. However, little information is available especially regarding the characteristics and influencing factors of breeding sites of An. sinensis in Yongcheng City, a representative region of unstable malaria transmission in the Huang-Huai River region of central China. The aims of this study were to determine the breeding site characteristics of An. sinensis and related environmental and physicochemical parameters, to find out which breeding site characteristics could best explain the presence of An. sinensis larvae, and to determine whether the breeding habit of An. sinensis has changed or not. METHODS: Random repeated cross sectional study was undertaken in six villages of the Yongcheng city characterized by different levels of the historical incidence of P. vivax malaria. The potential breeding sites of An. sinensis larvae in each village were examined twice per month both in the household courtyards and the village surroundings. The larval sampling was done by the standard dipping method. Some important breeding site characterizations were recorded and characterized. The anopheline mosquito larvae and emerged adults were identified to the species level morphologically and to sub-species by the ribosomal DNA PCR technique. Chi-square analysis and logistic regression analysis were applied to determine the importance of factors for explaining the presence or absence of An. sinensis larvae. RESULTS: According to the ribosomal DNA PCR assay, all sampled anopheline mosquito larvae and emerged adults belonged to An. sinensis. Only 3 containers that were sampled from the household courtyards were found to contain An. sinensis larvae. There were no differences in the species composition of mosquito larvae among containers that contained water in the household courtyards (P > 0.05). An. sinensis larvae were shown to be present in a total of 60 breeding sites in the village surroundings, this included 8 (13.3%) river fringes, 26 (43.3%) ponds, 23 (38.3%) puddles, and 3 (5.0%) irrigation/drainage ditches. Logistic regression analysis revealed that the breeding site type, water depth, chemical oxygen demand (COD), ammonia nitrogen, and sulphate were found to be the key factors determining the presence of An. sinensis larvae. Approximately 94.9% of An. sinensis larvae inhabited relatively large and medium-sized water bodies, with depths between 0.5 m and 1.0 m (73.3%), COD lower than 2 mg/L (75%), ammonia nitrogen lower than 0.4 mg/L (86.7%), and sulphate lower than 150 mg/L (58.3%), respectively. CONCLUSION: These results indicate that the majority of An. sinensis larval breeding sites were relatively large and medium-sized water bodies with depths between 0.5 m and 1.0 m, and containing low levels of COD, ammonia nitrogen, and sulphate, respectively. For effective An. sinensis larval control, the type of breeding site, water depth, COD, ammonia nitrogen, and sulphate should be given higher priority over other factors in areas where it is the primary vector.


Assuntos
Anopheles/crescimento & desenvolvimento , Vetores de Doenças , Ecossistema , Animais , Anopheles/classificação , Anopheles/genética , China , Estudos Transversais , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Água/química
9.
Parasit Vectors ; 4: 221, 2011 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-22115320

RESUMO

BACKGROUND: The knowledge of mosquito species diversity and the level of anthropophily exhibited by each species in a region are of great importance to the integrated vector control. Culicine species are the primary vectors of Japanese encephalitis (JE) virus and filariasis in China. Anopheles sinensis plays a major role in the maintenance of Plasmodium vivax malaria transmission in China. The goal of this study was to compare the abundance and host-seeking behavior of culicine species and An. sinensis in Yongcheng city, a representative region of P. vivax malaria. Specifically, we wished to determine the relative attractiveness of different animal baits versus human bait to culicine species and An. sinensis. RESULTS: Culex tritaeniorhynchus was the most prevalent mosquito species and An. sinensis was the sole potential vector of P. vivax malaria in Yongcheng city. There were significant differences (P < 0.01) in the abundance of both An. sinensis and Cx. tritaeniorhynchus collected in distinct baited traps. The relative attractiveness of animal versus human bait was similar towards both An. sinensis and Cx. tritaeniorhynchus. The ranking derived from the mean number of mosquitoes per bait indicated that pigs, goats and calves frequently attracted more mosquitoes than the other hosts tested (dogs, humans, and chickens). These trends were similar across all capture nights at three distinct villages. The human blood index (HBI) of female An. sinensis was 2.94% when computed with mixed meals while 3.70% computed with only the single meal. 19:00~21:00 was the primary peak of host-seeking female An. sinensis while 4:00~5:00 was the smaller peak at night. There was significant correlation between the density of female An. sinensis and the average relative humidity (P < 0.05) in Wangshanzhuang village. CONCLUSIONS: Pigs, goats and calves were more attractive to An. sinensis and Cx. tritaeniorhynchus than dogs, humans, and chickens. Female An. sinensis host-seeking activity mainly occurred from 19:00 to 21:00. Thus, we propose that future vector control against An. sinensis and Cx. tritaeniorhynchus in the areas along the Huang-Huai River of central China should target the interface of human activity with domestic animals and adopt before human hosts go to bed at night.


Assuntos
Anopheles/fisiologia , Culicidae/fisiologia , Mordeduras e Picadas de Insetos/parasitologia , Mordeduras e Picadas de Insetos/veterinária , Insetos Vetores/fisiologia , Animais , Bovinos , Galinhas , China , Cães , Comportamento Alimentar , Feminino , Cabras , Humanos , Masculino , Suínos
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