bluuebunny/crossref_metadata_2025 huggingface dataset:
Cirurgia de varizes: história e evolução
Authors: Medeiros Charles Angotti Furtado de
Published: March 2007

Como a safenectomia é uma cirurgia bem estabelecida, a utilização de um método pouco invasivo para obter os mesmos efeitos indica que os benefícios esperados a curto e médio prazo devem prevalecer sobre os riscos previstos. Entretanto, em se tratando de uma doença muito prevalente na população mundial, há grande preocupação por parte dos órgãos de saúde governamentais e das sociedades científicas correlacionadas sobre esse assunto, de tal forma que os argumentos sobre novas modalidades de tratamento devem estar bem fundamentados, inclusive para aceitação pelo público em geral.Com o intuito de se avaliar efetivamente novos dispositivos, devem ser conduzidos estudos em pacientes e com grupos controles que sejam bem delineados. É preciso submeter qualquer projeto de pesquisa sobre o assunto à apreciação do comitê de ética na instituição em que o trabalho será conduzido para aprovação prévia.
Correção endovascular do aneurisma de artéria poplítea bilateral
Authors: Medeiros Charles Angotti Furtado de , Gaspar Ricardo José
Published: March 2007

O primeiro relato de correção endovascular do aneurisma de artéria poplítea bem-sucedida foi descrito em 1994. Desde então, poucas séries e com apenas alguns casos foram publicadas. A seguir, os autores descrevem dois casos de correção endovascular de aneurisma de artéria poplítea bilateral realizada com sucesso.
Aneurisma venoso no pé: relato de casos e revisão da literatura
Authors: Dourado Octavio Cascaes , Miranda Aristoteles Guilliod de , Pinheiro Filho Antonio , Dourado Luciana Oliveira
Published: March 2007

Este relato descreve dois casos de aneurisma venoso no pé, apresentados sob a forma de tumoração indolor e não-pulsátil no dorso do pé e sem história de trauma. O ultra-som Doppler evidenciou formação ovalada, anecóica, em comunicação com a veia e com sinal Doppler venoso, sugestiva de aneurisma venoso. O diagnóstico foi confirmado pelo exame histopatológico, com dilatação aneurismática constituída pelos três componentes da parede da veia. O tratamento consistiu na ligadura e ressecção cirúrgica. Os aneurismas venosos são relativamente raros, havendo relato de sua presença em várias localizações, principalmente nos membros inferiores. Na revisão da literatura, não foram encontrados relatos de aneurismas venosos no pé.
Fístula aorto-esofágica secundária a fratura de endoprótese torácica: relato de caso
Authors: Nasser Felipe , Neser Adnan , Ingrund Jose Carlos , Zurstrassen Charles Edouard , Ribeiro Flavio de Macedo Cavaleiro , Moreira Ricardo Vagner , Arcenio Neto Elias , Burihan Marcelo Calil , Barros Orlando Costa
Published: March 2007

O tratamento endovascular dos aneurismas aórticos torácicos tem se desenvolvido consideravelmente nos últimos anos. No entanto, complicações tardias desta nova modalidade terapêutica apenas agora estão sendo observadas e analisadas. Fístulas aorto-esofágicas são complicações raras do tratamento endovascular dos aneurismas aórticos, sendo encontrados poucos relatos na literatura. O presente caso reporta um paciente com aneurisma aórtico torácico tratado há 4 anos e complicado com fratura da endoprótese. Após nova intervenção endovascular, foi observada extrusão da antiga endoprótese através do esôfago com formação de fístula. Apesar do tratamento realizado, o paciente evoluiu a óbito 9 dias após por hemorragia digestiva maciça. Aspectos técnicos e revisão de literatura são discutidos.
Initial experience with hand replantation after traumatic amputation in a nonspecialized center
Authors: Costa Cleinaldo de Almeida , Cabral Pedro Henrique Oliveira , Pinto Paulo Laredo , Pinheiro Júnior Manoel Jesus Coelho , Santos Neivaldo José Nazaré dos , Birolini Dário
Published: March 2007

Traumatic amputation of the hand is an incapacitating injury, requiring skilled surgical care. Achieving functional recovery in addition to salvage of the amputated extremity should be the goal of the patient care team, after the life of the patient is secured. This is a report of the first five cases of hand replantation after complete traumatic amputation in Manaus (Amazonas, Brazil), carried out at Hospital Pronto-Socorro Dr. João Lúcio Pereira Machado. The patients were all young males, mean age of 22.8 years, presenting at the emergency room with complete sharp amputation of the hand. After initial procedures according to the ATLS® protocol, the following surgical actions were taken: heparinization of the blood vessels of the amputated extremity, fixation of the bones, wide opening of the carpal tunnel, primary vascular anastomoses and repair of nerves and tendons. In four cases, viability and partial functional recovery of the replanted hands were achieved. The unsuccessful case was due to extensive venous thrombosis.Through this preliminary experience, we can state that hand replantation can be performed successfully in a nonspecialized hospital and that optimal results depend on adequate prehospital care, multidisciplinary surgical treatment and careful postoperative assistance.
Tratamento endovascular do aneurisma da aorta abdominal em paciente com insuficiência renal crônica
Authors: Pedron Cleoni , Palis Ana Carla M. , Ristow Arno von , Vescovi Alberto , Massière Bernardo , Cury Filho José Mussa , Gress Marcus , Medina Antonio Luiz de
Published: March 2007

A insuficiência renal crônica não-dialítica é uma contra-indicação relativa ao tratamento endovascular dos aneurismas da aorta abdominal. O uso de contrastes alternativos, como o gadolínio, além de fornecer imagens de baixa qualidade, está relacionado à nefrotoxicidade. Relatamos um caso de tratamento endovascular de aneurisma da aorta abdominal guiado por eco-Doppler colorido. Um paciente masculino de 82 anos, com aneurisma da aorta abdominal de 55 mm de diâmetro e clearance de creatinina de 17 ml/min, recebeu implante de endoprótese aórtica modular bifurcada, utilizando este método de imagem associado à radioscopia. Não foi empregado contraste iodado. O resultado imediato e os controles de 1 e 6 meses revelam completa exclusão do aneurisma. A função renal permanece inalterada. Concluímos que o implante de endoprótese guiado por eco-Doppler colorido em pacientes com insuficiência renal crônica não terminal e com anatomia favorável é um método factível e seguro.
Morphometric and microscopic evaluation of the effect of gallium nitrate as a root canal dressing in rat teeth submitted to late replantation
Authors: Mori Graziela Garrido , Garcia Roberto Brandão , Moraes Ivaldo Gomes de , Bramante Clóvis Monteiro , Bernardineli Norberti
Published: March 2007

The purpose of this study was to test a gallium nitrate solution, a resorption inhibitor, employed as a root canal dressing in teeth submitted to late replantation. Thirty maxillary right central incisors of rats were avulsed and kept dry for thirty minutes. The teeth were instrumented and the root surfaces were treated with 1% hypochlorite solution followed by application of 2% sodium fluoride. Thereafter, the teeth were divided into two groups according to the root canal dressing: Group I, solution of gallium nitrate; and Group II, calcium hydroxide paste. The teeth were then replanted in their respective sockets. The animals were killed at 15, 30 and 60 days after replantation and the samples were processed for morphometric and microscopic analysis. The results demonstrated that the gallium nitrate solution and the calcium hydroxide paste limited the root resorption, yet they did not impair its occurrence. It may be concluded that gallium nitrate solution and calcium hydroxide paste demonstrated similar performance.
Influence of image filters on the reproducibility measurements of alveolar bone loss
Authors: Alves Wivian Eiras Garcia Wong , Ono Evelise , Tanaka Jefferson Luis Oshiro , Medici Filho Edmundo , Moraes Luiz César de , Moraes Mari Eli Leonelli de , Castilho Julio Cezar de Melo
Published: March 2007

The reproducibility of measurements of alveolar bone loss on radiographs may be a problem on epidemiologic studies, as they are based on comparisons of the diagnosis of various examiners. The aim of the present research paper was to assess the inter- and intra-examiner reproducibility of measurements of the interproximal alveolar bone loss on non-manipulated digital radiographs and after the application of image filters. Five Oral Radiologists measured the distance between the cementoenamel junction (CEJ) to the alveolar crest or to the deepest point of the bony defect on 12 interproximal digital radiographs of molars and bicuspids of a dry human skull. The digital manipulation and the linear measurements were obtained with the Trophy Windows software (Throphy®). For each image, six different versions were created: 1) non-manipulated; 2) bright-contrast adjustment; 3) negative; 4) negative with brightness-contrast adjustment; 5) pseudo-colored; 6) pseudo-colored with brightness-contrast adjustment. In order to prevent interpretation bias because of the repetition of measurements, the examiners measured the radiographs in a random sequence. The two-way ANOVA test at 5% level of significance to compare the means of readings of the same operator with each filter indicated p<0.05 for the majority of operators, while the comparison between the mean values of operators using the same filter indicated p>0.05 for all filters. Based on the results, we concluded that linear measurements of interproximal alveolar bone loss on digital radiographs are highly reproducible among examiners. Nevertheless, the application of image filters significantly influenced the degree of intra-examiner reproducibility. Some filters even reduced the reproducibility of intra-examiner readings.
Speech evaluation with and without palatal obturator in patients submitted to maxillectomy
Authors: Carvalho-Teles Viviane de , Pegoraro-Krook Maria Inês , Lauris José Roberto Pereira
Published: March 2007

Most patients who have undergone resection of the maxillae due to benign or malignant tumors in the palatomaxillary region present with speech and swallowing disorders. Coupling of the oral and nasal cavities increases nasal resonance, resulting in hypernasality and unintelligible speech. Prosthodontic rehabilitation of maxillary resections with effective separation of the oral and nasal cavities can improve speech and esthetics, and assist the psychosocial adjustment of the patient as well.The objective of this study was to evaluate the efficacy of the palatal obturator prosthesis on speech intelligibility and resonance of 23 patients with age ranging from 18 to 83 years (Mean = 49.5 years), who had undergone inframedial-structural maxillectomy. The patients were requested to count from 1 to 20, to repeat 21 words and to spontaneously speak for 15 seconds, once with and again without the prosthesis, for tape recording purposes. The resonance and speech intelligibility were judged by 5 speech language pathologists from the tape recordings samples. The results have shown that the majority of patients (82.6%) significantly improved their speech intelligibility, and 16 patients (69.9%) exhibited a significant hypernasality reduction with the obturator in place. The results of this study indicated that maxillary obturator prosthesis was efficient to improve the speech intelligibility and resonance in patients who had undergone maxillectomy.
SEM analysis of the acid-etched enamel patterns promoted by acidic monomers and phosphoric acids
Authors: Shinohara Mirela Sanae , Oliveira Marcelo Tavares de , Hipólito Vinícius Di , Giannini Marcelo , Goes Mario Fernando de
Published: March 2007

ABSTRACT OBJECTIVE: Although self-etching bonding systems (SES) are indicated to prepare dental enamel for bonding, concerns have been expressed regarding their effectiveness. The aim of this study was to analyze the etching pattern (EP) of nine SES in comparison with 35% and 34% phosphoric acid etchants (FA) on intact (IN) and ground (GR) enamel surface. MATERIALS AND METHODS: Twenty-two human third molars were sectioned in mesial-distal and buccal-lingual directions, and four dental fragments were obtained from each tooth. Half of the fragments were ground using 600-grit SiC paper and the other half remained intact. The fragments were randomly assigned into 22 groups, according to the texture of enamel surface (IN and GR) and the technique to etch the enamel (34% FA, 35% FA, AdheSE primer; Brush & Bond; Clearfil Protect Bond primer; iBond; One-up Bond F; OptiBond Solo Plus primer; Tyrian SPE primer; Unifil Bond primer and Xeno III). Conditioners were applied to IN and GR enamel surfaces, according to the manufacturer's instructions. Specimens etched with phosphoric acids were washed with water, while the surfaces treated with SES were submitted to alternate rinsing with alcohol and acetone. The specimens were dried, sputter-coated and examined under a scanning electron microscope. RESULTS: For both IN and GR enamel surfaces, the EP of 34 and 35% FA was deeper and more homogeneous in comparison to EP of SES, except for Tyrian SPE. The acidic monomer action of self-etching systems was more effective on GR enamel. CONCLUSION: Most of the SES are less aggressive than phosphoric acid etchants and their etching effects were reduced on intact enamel surfaces.
The effect of alcohol consumption on periodontal bone support in experimental periodontitis in rats
Authors: Souza Daniela Martins de , Ricardo Lucilene Hernandes , Prado Marcela de Almeida , Prado Fernanda de Almeida , Rocha Rosilene Fernandes da
Published: March 2007

OBJECTIVE: The aim of this study was to evaluate the effect of the alcohol consumption on the periodontal bone support (PBS) in experimental periodontitis in rats. MATERIALS AND METHODS: Sixty-three male rats were divided into seven groups: G1 (control); G2 (10% ethanol); G3 (nutritional control of G2); G4 (20% ethanol); G5 (nutritional control of G4); G6 (30% ethanol) and G7 (nutritional control of G6). The groups G3, G5 and G7 received controlled diets with equivalent caloric amounts to those consumed in G2, G4 and G6 respectively, with the ethanol replaced by sucrose. After anesthesia, ligatures were installed around the mandibular first molar, leaving the contralateral teeth unligated. After 8 weeks, the rats were killed and their mandibles were radiographed to measure the percentage of PBS on the distal aspect. RESULTS: The intragroup analyses showed that presence of ligatures induced periodontitis (p<0.05). Unligated groups did not show significant differences among the percentages of PBS (p=0.1969). However, in ligated groups the rats that received alcohol (G2:48.71%±3.88; G4:47.66%±2.54; G6:47.32%±3.24) and the nutritional control group associated with a high concentration of ethanol (G7:47.40%±3.24) presented a significantly lower percentage of PBS than the other groups (G1:52.40%±2.75; G3:52.83%±2.41; G5:50.85%±4.14). CONCLUSIONS: These results demonstrated that alcohol consumption in rats may result in a direct effect on alveolar bone loss and increased development of periodontitis. In addition, they suggest that heavy caloric consumption of ethanol may also present an indirect effect on periodontal tissue as a consequence of malnutrition.
Oral findings in patients with Apert Syndrome
Authors: Dalben Gisele da Silva , Neves Lucimara Teixeira das , Gomide Marcia Ribeiro
Published: March 2007

INTRODUCTION: The Apert syndrome is a rare disorder of autosomal dominant inheritance caused by mutations in the FGFR2 gene at locus 10q26; patients with this syndrome present severe syndactyly, exophthalmia, ocular hypertelorism and hypoplastic midface with Class III malocclusion, besides systemic alterations. Most investigations available on the Apert syndrome address the genetic aspect or surgical management, with little emphasis on the oral aspects. OBJECTIVE: to investigate the oral findings, including dental anomalies, ectopic eruption of the maxillary permanent first molars and soft tissue alterations, in subjects with Apert syndrome. MATERIALS AND METHODS: clinical and radiographic examination of nine patients with Apert syndrome, aged 6 to 15 years, not previously submitted to orthodontic or orthognathic treatment. RESULTS: dental anomalies were present in all patients, with one to eight anomalies per individual. The most frequent anomalies were tooth agenesis, mainly affecting maxillary canines, and enamel opacities (44.4% for both). Ectopic eruption of maxillary first molars was found in 33.3% of patients; lateral palatal swellings were observed in 88.8% of patients. CONCLUSIONS: The occurrence of typical lateral palatal swellings agrees with the literature. The high prevalence of dental anomalies and ectopic eruption may suggest a possible etiologic relationship with the syndrome.
Teaching of bioethics in dental graduate programs in Brazil
Authors: Aires Carolina Patrícia , Hugo Fernando Neves , Rosalen Pedro Luiz , Marcondes Fernanda Klein
Published: March 2007

In the field of human research, researchers are faced with unexpected moral dilemmas, as a result of the development of technologies applied to health. Due to the great importance of this issue, our objective was to evaluate bioethics instruction in the education of researchers in Brazilian graduate programs in dentistry. Eighty-seven graduate programs in dentistry, recognized by CAPES (Coordination for the Improvement of Higher Education Personnel) were evaluated in this study. Data were extracted independently by two researchers from the CAPES website, and from the websites of the graduate programs, directly or via links to the programs available at the CAPES website. Forty-eight out of 87 programs had an ethics/bioethics course as part of their curricula. Of the graduation programs graded 5, 6 or 7 by CAPES, 38% included bioethics courses, while 62% of the programs graded 3 or 4 by CAPES had bioethics courses as part of their curricula. These findings are an alert to those involved in dental research education, as they showed that, although resolution 196/96 by the National Council of Health regulating human research in Brazil was published ten years ago, bioethics instruction in Brazilian graduate programs in dentistry is still at an incipient stage. This situation indicates a need for ethics pedagogy in the education of young researchers.
Evaluation of the quality of life of patients with oral cancer in Brazil
Authors: Andrade Fabiana Paula de , Antunes José Leopoldo Ferreira , Durazzo Marcelo Doria
Published: March 2007

This study performed a field trial of a Portuguese version of the University of Washington quality of life questionnaire (UW-QOL, 3rd version), aiming at appraising its ability to identify different patterns of health-related quality of life of patients with oral cancer in Brazil. Patients (N = 100) were interviewed as they were undergoing treatment for oral squamous cell carcinoma at a large Brazilian hospital ("Hospital das Clínicas", School of Medicine, University of São Paulo). The results were compared based on categories of socio-demographic and clinical characteristics of the patients. At a one-year follow-up, 20 patients had died, and 24 were considered dropouts. The remaining patients accounted for the longitudinal assessment of modifications in the self report of quality of life. Patients with larger tumours and neoplasms in the posterior part of the mouth presented significantly (p < 0.05) poorer indications of quality of life. Chewing was the poorest rated domain (35.0/100.0), and presented the highest proportion of complaints both at the baseline and at the follow-up assessments. The questionnaire allowed the identification of important contrasts (while comparing clinical characteristics) and similarities (while comparing socio-demographic status) among subsets of respondents, and it can contribute to reduce the impact of treatments and improve subsequent patient management.
Evaluation of surface characteristics of Ti-6Al-4V and Tilite alloys used for implant abutments
Authors: Lima Emilena Maria Castor Xisto , Silva Wander José da , Moura Juliana Silva , Faot Fernanda , Del Bel Cury Altair Antoninha
Published: March 2007

The aim of this study was to evaluate surface free energy (SFE), surface roughness (SR) and surface hardness (SH) of two commercially available materials for fabricating dental implant abutments. In addition, the specimens were investigated by scanning electron microscopy (SEM) to determine the surface morphology. Twenty five discs (5 x 2 mm) of Ti-6Al-4V and Tilite (Ni-Cr-Ti) alloys were used in this study. Surface free energy was determined by the contact angle formed between a drop of distilled, deionized water and the surface of the specimen of each material. The surface roughness was measured with a mechanical profilometer and the surface hardness was evaluated by means of the Vickers hardness micro indentation test. SFE, SR and SH data were analyzed using one-way ANOVA (p < 0.05). Statistical differences (p < 0.05) were found between Ti-6Al-4V (36.2 erg.cm-2; 0.2 µm) and Tilite (30.9 erg.cm-2; 0.16 µm) for SFE and SR. However, the differences between the surface hardness values of Ti-6Al-4V (325.0 kg/mm²) and Tilite (324.3 kg/mm²) were not statistically significant (p > 0.05). Evaluations by SEM revealed different surface morphology. Within the limits of this study, it can be concluded that the Ti-6Al-4V and Tilite alloys showed differences in surface properties, except for surface hardness, suggesting that both alloys may be considered appropriate for producing abutments. Further studies are, however, necessary to elucidate the biological responses to implant abutments made with these alloys.
Validation of the Portuguese version of the RDC/TMD Axis II questionnaire
Authors: Lucena Luciana Barbosa Sousa de , Kosminsky Maurício , Costa Lino João da , Góes Paulo Sávio Angeiras de
Published: March 2007

The present paper aimed at evaluating the validity of the Portuguese version of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis II Questionnaire. The sample was comprised of 155 patients with signs and symptoms of Temporomandibular Disorders (TMD), evaluated at the Orofacial Pain Control Center, School of Dentistry, University of Pernambuco, Brazil, between July 2003 and February 2004. Data collection was performed with the following tools: the RDC/TMD Axis I (clinical evaluation and TMD classification), and Axis II (psychosocial evaluation), as well as specific questionnaires for evaluation of Oral Health Related Quality of Life, namely, Oral Impacts on Daily Performances and the Oral Health Impact Profile-14, considered to be gold standard criteria. Validity evaluation consisted of internal consistency evaluation by the Cronbach alfa reliability test, reliability and reproducibility estimated by the Kappa test and the Spearman's correlation, and concurring validation through Spearman's correlation. The Portuguese version of the RDC/TMD Axis II questionnaire was considered consistent (Cronbach alfa = 0.72), reproducible (Kappa values from 0.73 to 0.91, p < 0.01), and valid (p < 0.01). It was concluded that this version showed valid and reproducible results for the Brazilian population, thus paving the way for including Brazil in transcultural epidemiological studies on TMD.
Densitometric analysis of the autogenous demineralized dentin matrix on the dental socket wound healing process in humans
Authors: Gomes Mônica Fernandes , Abreu Paula Pinheiro de , Morosolli Aline Rose Cantarelli , Araújo Marcelo Marotta , Goulart Maria das Graças Vilela
Published: March 2007

The aim of this study was to evaluate the effects of the autogenous demineralized dentin matrix (ADDM) on the third molar socket wound healing process in humans, using the guided bone regeneration technique and a polytetrafluoroethylene barrier (PTFE). Twenty-seven dental sockets were divided into three groups: dental socket (Control), dental socket with PTFE barrier (PTFE), and dental socket with ADDM slices associated to PTFE barrier (ADDM + PTFE). The dental sockets were submitted to radiographic bone densitometry analysis and statistical analysis on the 15th, 30th, 60th and 90th days using analysis of variance (ANOVA) and Tukey's test (p £ 0.05). The radiographic analysis of the ADDM + PTFE group showed greater homogeneity of bone radiopacity than the Control group and the PTFE group, during all the observation times. The dentin matrix gradually disappeared from the dental socket during the course of the repair process, suggesting its resorption during the bone remodeling process. It was concluded that the radiographic bone density of the dental sockets treated with ADDM was similar to that of the surrounding normal bone on the 90th day. The ADDM was biocompatible with the bone tissue of the surgical wounds of human dental sockets. The radiographic analysis revealed that the repair process was discreetly faster in the ADDM + PTFE group than in the Control and PTFE groups, although the difference was not statistically significant. In addition, the radiographic image of the ADDM + PTFE group suggested that its bone architecture was better than that of the Control and PFTE groups.
Length determination of zygomatic implants using tridimensional computed tomography
Authors: Koser Luciana Ribeiro , Campos Paulo Sérgio Flores , Mendes Carlos Maurício Cardeal
Published: March 2007

Considering the potential of tridimensional computed tomography (3D-CT) as a predictor of real bone dimensions, nine dried human skulls with maxillary edentulism were evaluated using images obtained by 3D-CT, prior to the installation of zygomatic implants, in order to obtain the measurements of the implants. In the analysis of correlation between the two 3D-CT examiners, a 75% agreement was found, and no correlation was found between them and the surgical measurement. The worst result was the surgical one, possibly because an inaccurate probe was used. Based on the obtained data, we concluded that the probe used is inaccurate, suggesting that the surgical probe be changed in its measurement scale. Agreement between surgeon and radiologist could possibly be obtained by using insertion guides, since what might have possibly caused the discrepancy in the results is the fact that the 3D-CT examiners and the surgeon used different implant insertion points. It is also possible that a larger sample might produce a more accurate evaluation, thus improving the results.
Water sorption of resin-modified glass-ionomer cements photoactivated with LED
Authors: Cefaly Daniela Francisca Gigo , Wang Linda , Mello Liliam Lucia Carrara Paes de , Santos Janaína Lima dos , Santos Jean Rodrigo dos , Lauris José Roberto Pereira
Published: March 2007

The Light Emitting Diodes (LED) technology has been used to photoactivate composite resins and there is a great number of published studies in this area. However, there are no studies regarding resin-modified glass-ionomer cements (RMGIC), which also need photoactivation. Therefore, the aim of this study was to evaluate water sorption of two RMGIC photoactivated with LED and to compare this property to that obtained with a halogen light curing unit. A resin composite was used as control. Five specimens of 15.0 mm in diameter x 1.0 mm in height were prepared for each combination of material (Fuji II LC Improved, Vitremer, and Filtek Z250) and curing unit (Radii and Optilight Plus) and transferred to desiccators until a constant mass was obtained. Then the specimens were immersed into deionized water for 7 days, weighed and reconditioned to a constant mass in desiccators. Water sorption was calculated based on weight and volume of specimens. The data were analyzed by two-way ANOVA and Tukey test (p < 0.05). Specimens photocured with LED presented significantly more water sorption than those photocured with halogen light. The RMGIC absorbed statistically significant more water than the resin composite. The type of light curing unit affected water sorption characteristics of the RMGIC.
Prevalence of dental caries in children born prematurely or at full term
Authors: Gravina Danuze Batista Lamas , Cruvinel Vanessa Resende Nogueira , Azevedo Tatiana Degani Paes Leme , Toledo Orlando Ayrton de , Bezerra Ana Cristina Barreto
Published: March 2007

The objective of this study was to evaluate the prevalence of dental caries in 192 children, 96 born prematurely and 96 at full term, in a regional hospital in Brazil. Mean age at clinical examination was 40.72 months in the full-term group (G1) and 30.44 months in the premature group (G2). The children were divided in two age subgroups: 0 to 3 and 4 to 6 years. Statistical results (Student's t and Kruskal-Wallis tests) showed that dmft was 0.43 for G1 and 0.01 for G2 in the 0-3 age subgroup, and 1.7 for G1 and 1.1 for G2 in the 4-6 age subgroup. Differences were significant between G1 and G2 only in the 0-3 age subgroup (p = 0.047). Caries evaluation showed that, of the 96 children in G1, 75 were caries free, while in G2, 84 did not have the disease. These differences were not significant (p = 0.088). The lower mean dmft found in the 0-3 age subgroup in G2 may be attributed to routines established by the hospital's neonatology staff, such as frequent dental visits and preventive instructions about oral habits, oral hygiene and diet. After this age, with the completion of the primary dentition, values increased and became similar between the G1 and G2 groups. Results also suggested a highly skewed distribution since most caries were found in only a small number of children.
An Effective Fluid Formulation to Remove Drilling-Fluid MudCake in Horizontal and Multilateral Wells
Authors: Nasr-El-Din H. A. , Al-Otaibi M. B. , Al-Qahtani A. A. , Samuel M.
Published: March 2007

Cleanup of drilling-fluid filter cake in long horizontal and multilateral wells is a difficult task. Both mechanical (water jetting) and chemical means (acids, oxidizers, chelating agents, and enzymes) have been used in the field. However, these methods have limitations which can adversely affect well performance. Water jetting may adversely impact well productivity through sanding and water blockage. Acids and oxidizers are very reactive but nonspecific species. Enzymes can be used to degrade starch and xanthan polymers. However, they are not effective in heterogeneous formations with high-permeability streaks which will require large volumes of treatment fluids.

This paper examines the use of a combination of enzymes and a new class of viscoelastic surfactants. In this system, enzymes are used to degrade starch, whereas the viscoelastic surfactant is used to increase the viscosity and solids-carrying capacity of the treatment fluids.

Extensive lab studies were conducted to examine the compatibility of viscoelastic surfactants with enzymes. The apparent viscosity of the enzyme/viscoelastic surfactant solutions was measured as a function of shear rate (57 to 1,740 s−1) and temperature (25 to 100°C). Surface tension was measured at various temperatures up to 140°C. Static fluid-loss tests were performed in a high-pressure/high-temperature (HP/HT) cell to assess the effectiveness of the combined system in cleaning filter cakes formed by water-based drilling mud.

Experimental results indicated that the viscoelastic surfactant is compatible with the enzyme system. The low shear viscosity of the combined system is high enough to lift suspended solids during well flowback following the treatment. The addition of the viscoelastic surfactant to the enzyme solutions significantly reduced the surface tension of the enzyme solutions, which will shorten the time required to lift treatment fluids from the formation. The efficiency of the enzymes in degrading starch did not change significantly because of the presence of the viscoelastic surfactant.
Cement Mechanical-Property Measurements Under Wellbore Conditions
Authors: Reddy B. R. , Santra Ashok , McMechan David , Gray Dennis , Brenneis Chad , Dunn Rick
Published: March 2007

Cement integrity preservation during completion, stimulation, production, and even well abandonment is of critical importance for an operator from long-term economic, productivity, and safety perspectives. Traditionally, compressive strengths have been considered indicators of cement integrity. However, numerous squeeze cementing jobs regularly performed on completed wells are testament to the poor correlation between compressive strengths and cement integrity. Additional mechanical properties such as tensile and flexural strengths, elastic modulus, and Poisson's ratio are being taken into account with increasing frequency for maximizing the cement sheath performance during the life of the well. Unfortunately, all such measurements are performed on samples that have been cured, either under wellbore conditions (for example, pressure and temperature) or laboratory conditions (for example, atmospheric pressure), but tested at atmospheric pressure and temperature. Such properties may at best be useful for comparing different formulations in the selection process, but do not provide information about cement properties under downhole conditions.

Using a combination of ultrasonic shear wave and compression wave measurements, dynamic mechanical properties such as elastic modulus, bulk modulus, Poisson's ratio, and compressive strength are measured under pressure and temperature. These measurements are compared with mechanical properties obtained from load vs. displacement tests under static conditions and acoustic compression and shear wave measurements at atmospheric pressure and temperature. Correlations are calculated for several slurries, and the results are presented. These results include cases where the measurements made using this method demonstrated unique advantages over the conventional load vs. displacement techniques.
GIS as an information technology framework for water modeling
Authors: Cesur Durmus
Published: March 2007

The sustainable and equitable management of water requires integrated analysis which includes the integration of a multitude of modeling systems at the core. The linkage of the modeling systems and components is the main bottleneck to achieve the integrated modeling solutions that maintain the integrity of the entire environmental system for comprehensive analysis, planning and management. In this paper, the use of a Geographic Information System (GIS), as an integration framework for the water modeling systems, together with object-oriented data modeling and programming schemes is explained. Integration of the modeling systems on a GIS platform, through a surface-water-specific GIS data model, Arc Hydro, and interface data models as data repositories for common water features, hydrologic and hydraulic modeling elements, is presented with a case study. Arc Hydro served as an integration data model for the simulation models of concern. Time series data transfer between modeling system at the information exchange points is facilitated using object-oriented linkage programs, and relationships among the modeling elements are established through Arc Hydro.

In the case study, the HEC-HMS hydrologic model and the HEC-RAS hydraulic model are integrated into an automated floodplain mapping application on a GIS. The implementation of the integration methodology is presented.
HidroSIG: an interactive digital atlas of Colombia's hydro-climatology
Authors: Poveda Germán , Mesa Oscar J. , Vélez Jaime I. , Mantilla Ricardo , Ramírez Jorge M. , Hernández Olver O. , Borja Andrés F. , Urzola Jheison A.
Published: March 2007

An interactive digital hydro-climatologic atlas of Colombia, HidroSIG, has been developed with distributed maps and time series of monthly and long-term average hydro-climatological variables, as part of a more comprehensive geographical information system (GIS) and database. Maps were developed so as to capture the spatial variability of the diverse geophysical fields resulting from major geographic, topographic and climatic controls. HidroSIG contains modules that perform diverse hydrological and geomorphological estimations including: (i) extraction of geomorphological parameters of drainage channel networks and river basins from Digital Elevation Maps (DEM), (ii) estimation of long-term and monthly water balances and other hydro-climatic variables in river basins, (iii) estimation of extreme flows (floods and low flows) of different return periods along the river network of Colombia by combining long-term water balance with scaling methods, (iv) interpolation of geophysical fields, (v) temporal analysis of hydrological time series including standardization, autocorrelation function, Fourier spectrum and cross-correlations analysis with macro-climatic indices, and (vi) simulation of rainfall–runoff processes using a hydrologic distributed model. The most relevant features of HidroSIG are described in terms of the methods used for hydrologic estimations, visualization capabilities, tools for analysis and interpolation of hydro-climatic variables in space and time, geomorphologic analysis and estimation from DEMs, and other features. Water resources planning and management and diverse socio-economic sectors benefit from this freely available database and computational tool.
Ensemble modeling approach for rainfall/groundwater balancing
Authors: Laucelli D. , Giustolisi O. , Babovic V. , Keijzer M.
Published: March 2007

This paper introduces an application of machine learning, on real data. It deals with Ensemble Modeling, a simple averaging method for obtaining more reliable approximations using symbolic regression. Considerations on the contribution of bias and variance to the total error, and ensemble methods to reduce errors due to variance, have been tackled together with a specific application of ensemble modeling to hydrological forecasts. This work provides empirical evidence that genetic programming can greatly benefit from this approach in forecasting and simulating physical phenomena. Further considerations have been taken into account, such as the influence of Genetic Programming parameter settings on the model's performance.
Combining targeted sampling and fluorometry to identify human fecal contamination in a freshwater creek
Authors: Hartel Peter G. , Rodgers Karen , Moody Gwyneth L. , Hemmings Sarah N. J. , Fisher Jared A. , McDonald Jennifer L.
Published: March 2007

Many bacterial source tracking (BST) methods are too expensive for most communities to afford. In an effort to develop an inexpensive method of detecting human sources of fecal contamination in a freshwater creek during baseflow and stormflow conditions, we combined targeted sampling with fluorometry. Targeted sampling is a prelude to BST and finds sources of fecal contamination by continued sampling and resampling over ever-decreasing distances. Fluorometry identifies human fecal contamination in water by detecting fluorescing compounds, optical brighteners, from laundry detergents. Potato Creek, a freshwater creek in Georgia (U.S.A.), had three reaches identified as containing high numbers of fecal bacteria, and these reaches were sampled by targeted sampling and fluorometry. Targeted sampling quickly and inexpensively identified humans, cattle, and dogs as the major sources of fecal contamination in the first, second, and third reaches, respectively. Fluorometric values were consistent with these identifications, but high fluorometric values were sometimes observed in areas with no fecal contamination. One likely cause of these false-positive signals was fluorescence from organic matter. For targeted sampling, the cost of each sample was $6, with a one-time equipment cost of $3,650; for fluorometry, the cost of each sample was negligible, with a one-time equipment cost of $14,250. This was the first study of this relatively inexpensive combination in freshwater during both baseflow and stormflow conditions.
Speeding up solar disinfection (SODIS): effects of hydrogen peroxide, temperature, pH, and copper plus ascorbate on the photoinactivation of E. coli
Authors: Fisher Michael B. , Keenan Christina R. , Nelson Kara L. , Voelker Bettina M.
Published: March 2007

Solar disinfection, or SODIS, shows tremendous promise for point-of-use drinking water treatment in developing countries, but can require 48 h or more for adequate disinfection in cloudy weather. In this research, we show that a number of low-cost additives are capable of accelerating SODIS. These additives included 100-1000 μM hydrogen peroxide, both at room temperature and at elevated temperatures, 0.5 – 1% lemon and lime juice, and copper metal or aqueous copper plus ascorbate, with or without hydrogen peroxide. Laboratory and field experiments indicated that additives might make SODIS more rapid and effective in both sunny and cloudy weather, developments that could help make the technology more effective and acceptable to users.
Estimating the costs and health benefits of water and sanitation improvements at global level
Authors: Haller Laurence , Hutton Guy , Bartram Jamie
Published: March 2007

The aim of this study was to estimate the costs and the health benefits of the following interventions: increasing access to improved water supply and sanitation facilities, increasing access to in house piped water and sewerage connection, and providing household water treatment, in ten WHO sub-regions. The cost-effectiveness of each intervention was assessed in terms of US dollars per disability adjusted life year (DALY) averted. This analysis found that almost all interventions were cost-effective, especially in developing countries with high mortality rates. The estimated cost-effectiveness ratio (CER) varied between US$20 per DALY averted for disinfection at point of use to US$13,000 per DALY averted for improved water and sanitation facilities. While increasing access to piped water supply and sewage connections on plot was the intervention that had the largest health impact across all sub-regions, household water treatment was found to be the most cost-effective intervention. A policy shift to include better household water quality management to complement the continuing expansion of coverage and upgrading of services would appear to be a cost-effective health intervention in many developing countries.
Global cost-benefit analysis of water supply and sanitation interventions
Authors: Hutton Guy , Haller Laurence , Bartram Jamie
Published: March 2007

The aim of this study was to estimate the economic benefits and costs of a range of interventions to improve access to water supply and sanitation facilities in the developing world. Results are presented for eleven developing country WHO sub-regions as well as at the global level, in United States Dollars (US$) for the year 2000. Five different types of water supply and sanitation improvement were modelled: achieving the water millennium development goal of reducing by half in 2015 those without improved water supply in the year 1990; achieving the combined water supply and sanitation MDG; universal basic access to water supply and sanitation; universal basic access plus water purification at the point-of-use; and regulated piped water supply and sewer connection. Predicted reductions in the incidence of diarrhoeal disease were calculated based on the expected population receiving these interventions. The costs of the interventions included estimations of the full investment and annual running costs. The benefits of the interventions included time savings due to easier access, gain in productive time and reduced health care costs saved due to less illness, and prevented deaths. The results show that all water and sanitation improvements are cost-beneficial in all developing world sub-regions. In developing regions, the return on a US$1 investment was in the range US$5 to US$46, depending on the intervention. For the least developed regions, investing every US$1 to meet the combined water supply and sanitation MDG lead to a return of at least US$5 (AFR-D, AFR-E, SEAR-D) or US$12 (AMR-B; EMR-B; WPR-B). The main contributor to economic benefits was time savings associated with better access to water and sanitation services, contributing at least 80% to overall economic benefits. One-way sensitivity analysis showed that even under pessimistic data assumptions the potential economic benefits outweighed the costs in all developing world regions. Further country case-studies are recommended as a follow up to this global analysis.
Cost-effectiveness of water quality interventions for preventing diarrhoeal disease in developing countries
Authors: Clasen Thomas , Haller Laurence , Walker Damian , Bartram Jamie , Cairncross Sandy
Published: March 2007

Using effectiveness data from a recent systematic review and cost data from programme implementers and World Health Organization (WHO) databases, we conducted a cost-effectiveness analysis to compare non-piped in source- (dug well, borehole and communal stand post) and four types of household- (chlorination, filtration, solar disinfection, flocculation/disinfection) based interventions to improve the microbial quality of water for preventing diarrhoeal disease. Results are reported for two WHO epidemiological sub-regions, Afr-E (sub-Saharan African countries with very high adult and child mortality) and Sear-D (South East Asian countries with high adult and child mortality) at 50% intervention coverage. Measured against international benchmarks, source- and household-based interventions were generally cost effective or highly cost effective even before the estimated saving in health costs that would offset the cost of implementation. Household-based chlorination was the most cost-effective where resources are limited; household filtration yields additional health gains at higher budget levels. Flocculation/disinfection was strongly dominated by all other interventions; solar disinfection was weakly dominated by chlorination. In addition to cost-effectiveness, choices among water quality interventions must be guided by local conditions, user preferences, potential for cost recovery from beneficiaries and other factors.
Mercury pollution from irrigation with treated sewage water (TSW)
Authors: Pillay A. E. , Yaghi B. , Williams J. R. , Al-Kindy S.
Published: March 2007

The lack of potable water in arid countries leads to the use of treated sewage water (TSW) for crop growth. Mercury accumulation (up to 500 ng/g) in agricultural soil originating from daily irrigation with TSW was found at two sites fed separately from a hospital sewage plant and an industrial plant. A control site irrigated with potable water ([Hg] <0.01 ng/ml) had much reduced levels in soil (<12 ng/g). Cold-vapour analysis of TSW revealed that Hg concentrations fluctuated widely, and were between 10-100 times higher than those of potable water. The TSW data originated from a total of 46 samples (1L each), from both plants, collected over a 6-month period. The Hg levels varied from 0.1 to 1.0 ng/ml, which suggested that the possible source of the accumulation could be found in continuous irrigation with comparatively higher Hg levels. Remedial measures could be approached from the perspective of curbing this inconsistency to produce more consistent Hg concentrations below 0.5 ng/ml. It was found that the electrical conductivity of TSW is a useful indicator to rapidly monitor fluctuations in treatment. A novel development in the study was the potential capacity of the plastic TSW discharge-pipes to behave as crude ‘chromatographic’ columns for possible Hg adsorption. If this property of the pipes is developed further it could have a considerable mitigating effect on the Hg levels. Possible recommendations for remediation to limit the Hg levels and promote sustainable development are discussed.