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1.
J Hum Hypertens ; 25(2): 106-13, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20182452

RESUMEN

Endothelin-1 (ET-1), a circulating vasoactive peptide with potent vasoconstricting and mitogenic properties, may contribute to target-organ damage in hypertension. We investigated whether plasma levels of C-terminal pro-endothelin-1 (CT-pro-ET-1) are associated with left ventricular (LV) mass and aortic root diameter in African-American adults with hypertension. Plasma CT-pro-ET-1 was measured by an immunoluminometric assay in 1041 African Americans (65±9 years, 72% women) with hypertension. LV mass and aortic root diameter were measured according to the American Society of Echocardiography guidelines, and LV mass was indexed by height to the power 2.7 (LVMi). Multivariable regression analyses were used to assess whether plasma CT-pro-ET-1 was associated with LVMi and aortic root diameter, independent of potential confounding variables. Plasma CT-pro-ET-1 was modestly correlated with LVMi (r=0.21, P<0.0001) and aortic root diameter (r=0.09, P=0.004). In separate multivariable regression models that adjusted for age, sex, body mass index, total and high-density lipoprotein cholesterol, smoking history, diabetes, history of myocardial infarction or stroke, and blood pressure-lowering medication and statin use, log CT-pro-ET-1 was significantly associated with greater LVMi (P=0.001) and larger aortic root diameter (P=0.006). CT-pro-ET-1 is independently associated with LVMi and aortic root diameter and may be a marker of target-organ damage in African-Americans adults with hypertension.


Asunto(s)
Válvula Aórtica/fisiopatología , Endotelina-1/sangre , Ventrículos Cardíacos/fisiopatología , Hipertensión , Hipertrofia Ventricular Izquierda/sangre , Mediciones Luminiscentes/métodos , Fragmentos de Péptidos/sangre , Negro o Afroamericano , Anciano , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Biomarcadores , Factores de Confusión Epidemiológicos , Ecocardiografía Doppler , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Hipertensión/epidemiología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Persona de Mediana Edad , Análisis de Regresión , Factores de Riesgo , Estados Unidos/epidemiología
2.
Artículo en Inglés | MEDLINE | ID: mdl-20580277

RESUMEN

OBJECTIVE: The aim of this study was to determine the influence of operator experience on the shaping ability of ProFile and K3 nickel-titanium rotary instruments in simulated root canals. STUDY DESIGN: One hundred sixty simulated canals consisting of 4 different shapes in terms of angle and position of curvature were prepared by experienced and inexperienced operators. One experienced operator prepared 80 canals and 2 inexperienced operators prepared 80 canals with a crown-down technique using either ProFile or K3 .06 taper instruments. Images of the canals were taken, using a camera attached to a computer with image analysis software, before surgery and after preparation to sizes 20, 25, and 30 to working length. Postoperative images were combined with the preoperative image to highlight the amount and position of material removed during preparation as well as the shape of the prepared canal. RESULTS: Overall, there was a highly statistically significant difference (P<.001) between the instruments for the time taken to prepare the canals, with K3 instruments taking a mean of 4.9 minutes and ProFile 6.0 minutes. Six instruments fractured (3 in each operator category); 4 were ProFile instruments. Four instruments deformed, all with the inexperienced operators; 3 were K3. No perforations or zips were observed; however, 1 danger zone (created by the experienced operator using K3 instruments) and 1 ledge (created by an inexperienced operator using K3 instruments) were created. Twelve outer widenings were created with a highly significant difference (P<.001) between the operator and instrument used. There was a highly significant difference by instrument (P<.001), and experience (P=.008) regarding absolute transportation at the beginning of the curve and a statistically significant difference (P=.031) for the instrument used regarding absolute transportation half way to the orifice. CONCLUSION: The experienced operator prepared canals more quickly and safely than the inexperienced operators when using K3 instruments; both used ProFile instruments quickly and safely. Inexperienced operators would be advised to train using less aggressive instruments and when confident could progress to other instrument designs.


Asunto(s)
Competencia Clínica , Instrumentos Dentales/clasificación , Cavidad Pulpar/cirugía , Preparación del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Diseño de Equipo , Humanos , Preparación del Conducto Radicular/métodos
3.
Int J Dent Hyg ; 7(1): 55-61, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19215312

RESUMEN

OBJECTIVE: The aim of this study was to assess the relationships between aggressive periodontitis (AgP), caries and smoking. METHOD AND MATERIALS: A cross-sectional study was conducted among patients who were specifically referred to the Dental Teaching Clinic in Irbid, Jordan for periodontal treatment. Self-administered questionnaire related to socio-demographic data and smoking habits was completed. The oral hygiene, gingival status, periodontal health and dental status of the participants was determined by using the plaque index of Silness and Loe [Acta Odontol Scand, 22 (1964), 121], the gingival index of Loe and Silness [Acta Odontol Scand, 21 (1963), 233], clinical attachment level (CAL) and decayed, missing and filled teeth (DMFT) index respectively. RESULT: The prevalence of smoking was greater in chronic periodontitis (CP) group (44.2%) than in either chronic gingivitis (CG) (27.4%) or AgP (29.9%) group. Self-reported perio-diseases in the close family was more prevalent (77%) among subjects diagnosed with AgP. The mean plaque scores were significantly higher for smoker than non-smoker in AgP group only (P = 0.04), with significantly greater plaque and gingival scores in CG and CP groups than AgP group (P = 0.012, 0.004). A significantly greater mean gingival scores were noted among CG and CP groups than AgP group (P = 0.004). The mean CAL was higher in smokers than in non-smokers in the three groups, with statistically significant differences in CP and AgP groups (P = 0.04, 0.01 respectively).The mean number of DMFT was significantly higher in smoker than in non-smoker of all age groups (P = 0.016, 0.043 and 0.01). However, mean DMFT was significantly greater in CP and CG than AgP groups. CONCLUSION: It was concluded that (i) higher plaque and gingival index among smokers in all groups; (ii) significant difference in the CAL between smoker and non-smoke in CP and AgP groups; (iii) significant increase in caries risk among smokers in all groups; (iv) smokers and non-smokers of AgP group had significantly lower mean DMFT scores than those of CG or CP groups.


Asunto(s)
Índice CPO , Enfermedades Periodontales/epidemiología , Fumar/epidemiología , Adolescente , Adulto , Periodontitis Agresiva/epidemiología , Pérdida de Hueso Alveolar/epidemiología , Enfermedad Crónica , Periodontitis Crónica/epidemiología , Estudios Transversales , Índice de Placa Dental , Femenino , Gingivitis/epidemiología , Humanos , Jordania/epidemiología , Masculino , Índice de Higiene Oral , Pérdida de la Inserción Periodontal/epidemiología , Índice Periodontal , Bolsa Periodontal/epidemiología , Adulto Joven
4.
J Dent ; 32(4): 301-7, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15053913

RESUMEN

OBJECTIVES: The objective of this study was to evaluate radiographically the technical standard of root canal treatment performed by undergraduate dental students at the Dental Teaching Center in Jordan. METHODS: A random sample of 8500 records of dental patients was examined. A total of 542 endodontically treated teeth with 912 roots were evaluated. Periapical radiographs were used to assess the technical quality of the root canal filling. The length of each root canal filling was categorized as acceptable, short and overfilled based on their relationship with the radiographic apex. Density and taper of filling was evaluated based on the presence of voids and the uniform tapering of the filling, respectively. Chi-square analysis was used to determine statistically significant differences between adequacy of root canal filling in each group of teeth according to its location, position and curvature. RESULTS: Sixty-one percent of roots had fillings of acceptable length, while 34.5% were short and 4.2% were overfilled. The root canal fillings of 47.4% were found to be adequate. Adequate fillings were found more in maxillary than mandibular teeth (P < 0.005), anterior compared to posterior teeth (P < 0.05) and in straight canals compared to curved canals (P < 0.001). CONCLUSION: The technical quality of root canal treatment performed by undergraduate dental students using step-back preparation and lateral condensation was found to be less than 50%. Review of the endodontic curriculum requirements, specialized clinical supervision and increasing the time of training at the preclinical and clinical levels should improve this quality.


Asunto(s)
Cavidad Pulpar/diagnóstico por imagen , Tratamiento del Conducto Radicular/normas , Estudiantes de Odontología , Adolescente , Adulto , Distribución de Chi-Cuadrado , Niño , Endodoncia/educación , Humanos , Jordania , Mandíbula , Maxilar , Persona de Mediana Edad , Evaluación de Procesos, Atención de Salud , Radiografía , Estudios Retrospectivos , Materiales de Obturación del Conducto Radicular/normas , Obturación del Conducto Radicular/normas , Preparación del Conducto Radicular/normas , Propiedades de Superficie , Ápice del Diente/diagnóstico por imagen
5.
Int Endod J ; 32(3): 183-90, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10530205

RESUMEN

CASE REPORT: Talon cusp is an uncommon dental anomaly manifested as an accessory cusp-like structure on the crown of anterior teeth. This report describes two unusual cases of talon cusp. Case 1 showed bilateral anomalous cusps on the palatal aspects of maxillary supernumerary teeth, causing premature contact and tooth impaction. In case 2, a double-fused talon cusp was projected from the palatal surface of a large geminated central incisor. A talon cusp is not an innocuous defect, as it may provide a substantial diagnostic, treatment planning and procedural challenge. Early diagnosis and management are important to avoid complications.


Asunto(s)
Incisivo/anomalías , Anomalías Dentarias/terapia , Corona del Diente/anomalías , Adolescente , Niño , Técnica Odontológica de Alta Velocidad , Femenino , Humanos , Ajuste Oclusal
8.
Int Endod J ; 31(4): 275-81, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9823117

RESUMEN

The aim of this study was to determine the shaping ability of ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips in simulated canals. A total of 40 simulated root canal made up of four different shapes in terms of angle and position of curvature were prepared by ProFile instruments using the 'crown down' approach recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, loss of canal length and three-dimensional canal form. The time necessary for canal preparation was on average 5.2 min and was not influenced significantly by canal shape. Three instrument fractures occurred and a further 3 instruments deformed; size 35 instruments failed the most (4) followed by size 30 (2), four of the failures occurred in canals with 40 degrees curves. None of the canals became blocked with debris and change in working distance was minimal. Intra-canal impressions of canal form demonstrated that most canals had apical stops and smooth canal walls whereas all canals had good flow and taper. Under the conditions of this study, ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips prepared simulated canals rapidly and created good three-dimensional form.


Asunto(s)
Instrumentos Dentales , Preparación del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Estudios de Evaluación como Asunto , Procesamiento de Imagen Asistido por Computador , Níquel , Preparación del Conducto Radicular/métodos , Titanio
9.
Int Endod J ; 31(4): 282-9, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9823118

RESUMEN

The aim of this study was to determine the shaping ability of ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips in simulated canals. A total of 40 simulated root canals made up of four different shapes in terms of angle and position of curvature were prepared by ProFile instruments using the 'crown down' approach recommended by the manufacturer. Part 2 of this two-part report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and the overall post-operative shape. Out of 37 completed specimens 9 zips (24%) and one ledge (3%) were created, but no perforations or danger zones were found. There were significant differences (P < 0.01) between canal shapes for the incidence of zips and elbows but not for their distance from the end-point of preparation. At specific positions along the canal length there were significant differences between the canal types in terms of their mean total width; overall, at the end-point of preparation and along the curved portion of the canals those specimens with 40 degrees curves were widest. This trend continued for the width of material removed from the outer aspect of the canal curves, whereas along the inner aspect of curves more material was removed in the 20 degrees canals. Overall, transportation was towards the outer aspect of the curve at the end-point of preparation and along the curved portion of canals but more balanced along the straight coronal section. Absolute transportation was small and below 0.1 mm at every position including the zips. Under the conditions of this study, ProFile nickel-titanium rotary instruments with ISO sized tips produced a larger number of zips than expected; however, the degree of zipping was limited and relatively minor.


Asunto(s)
Instrumentos Dentales , Preparación del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Diseño de Equipo , Estudios de Evaluación como Asunto , Níquel , Preparación del Conducto Radicular/métodos , Titanio
10.
J Endod ; 24(5): 364-71, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9641115

RESUMEN

A total of 160 simulated canals of various angles and positions of curvature were prepared by hand using either Mani Flexile Files, Mani SEC-O Files, Maillefer Flexofiles, or Zipperer Flexicut Files. After orifice enlargement, each file type was used to prepare 40 canals employing a balanced force motion and a modified double-flared technique. Pre- and postoperative images of the canals were taken with a videocamera, and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre- and postoperative views. Significant differences (p < 0.001) in preparation time were observed, with Flexile Files being quickest and SEC-O Files being slowest. Overall, Flexofiles and Flexicut Files deformed significantly more (p < 0.001) than Flexile and SEC-O Files. The incidence of canal blockage was not influenced by instrument type, but the incidence of apical extrusion was significantly greater (p < 0.001) with SEC-O Files. SEC-O Files created significantly fewer (p < 0.001) and significantly narrower (p < 0.001) zips, with significantly less (p < 0.001) removal of material from the outer aspect of the curve and thus significantly less (p < 0.001) transportation. Flexicut Files created the widest canals apically, with the greatest removal of material from the outer aspect of the curve and the most transportation. Flexofiles created significantly more (p < 0.001) perforations. Under the conditions of this study, obvious differences between instruments were highlighted with SEC-O Files preparing canals more safely and with least destruction. The unique rounded tip of the SEC-O Files may have had an influence on the outcome.


Asunto(s)
Instrumentos Dentales , Preparación del Conducto Radicular/instrumentación , Análisis de Varianza , Distribución de Chi-Cuadrado , Cavidad Pulpar/anatomía & histología , Diseño de Equipo , Falla de Equipo , Estudios de Evaluación como Asunto , Humanos , Microscopía Electrónica de Rastreo , Modelos Estructurales , Factores de Tiempo
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