Showing papers by "Jordan University of Science and Technology published in 1998"

Etiology and incidence of maxillofacial fractures in the north of Jordan

Abstract: Objective. The objective of this investigation was to determine the causes and incidence of maxillofacial fractures in the country of Jordan. Design. A retrospective review of patient records and radiographs for the 5-year period from 1992 to 1997 was conducted. Data regarding age, gender, cause of fracture, anatomic site, and treatment modalities were reviewed. Results. During the 5-year period, 563 patients with 756 maxillofacial fractures were treated. The age range was 5 to 73 years (mean, 28.8 years). Of the 563 patients, 75.3% were male, with the peak incidence occurring in the age group 20 to 29 years. The bone of fracture was most frequently the mandible (seen in 419 cases, or 74.4% of the total), followed by the maxilla (76 cases; 13.5%), the zygomatic arch (60 cases; 10.7%), and the alveolar process (8 cases; 1.4%). Of the fractures, 55.2% were due to traffic accidents, 19.7% to accidental falls, and 16.9% to assaults. Most patients (82.3%) were treated by closed reduction surgery (45.2% with eyelet wiring; 54.8% with arch bars and intermaxillary fixation). Only 17.7% of patients were treated by open reduction surgery. All maxillary fractures were treated by orbital and circumzygomatic suspension with interdental wiring and intermaxillary fixation. Of the zygomatic complex fractures, 26 cases were treated with Gillies' temporal approach, 20 with percutaneous hook elevation, and 14 with observation alone. Conclusion. The findings support the view that both the causes and the incidence of maxillofacial fractures vary from one country to another.

Tomato Root and Shoot Responses to Salt Stress Under Different levels of Phosphorus Nutrition

Abstract: Crops differ in their ability to grow under saline conditions and their responses are quite variable and not fully understood. This study was conducted to evaluate the root and shoot responses of tomato to salt stress conditions under different levels of phosphorus (P) nutrition. Tomato seedlings (cv Riogrande) were grown in 500 mL glass jars containing Hoagland's solutions which were salinized by four levels of NaCl salt (0,50,100, and 150 mM NaCl) and/or enriched with three P levels (0.5,1, and 2 mM P) making nine combination treatments. Plants were harvested at the vegetative growth stage and data were collected for root and shoot characteristics. The results indicate that increasing salinity stress was accompanied by significant reductions in shoot weight, plant height, number of leaves per plant, and a significant increase in leaf osmotic potential and peroxidase activity regardless of the level of P supplied. Both root length and root surface area per plant were decreased significantly unde...

Treatment of mandibular odontogenic keratocysts.

Abstract: Objective. The purpose of this study was to report our experience with surgical treatment of 31 mandibular odontogenic keratocysts, with special reference to their recurrence, and to review the literature on this subject. Study design. A retrospective analysis was conducted of all odontogenic cysts treated in the Department of Oral Surgery and Oral Medicine at Jordan University of Science and Technology between 1989 and 1995. Of a total of 227 odontogenic cysts, 31 odontogenic keratocysts were histopathologically diagnosed preoperatively. They were surgically treated through an intraoral approach by resection without continuity defects. The lower border of the mandible and/or the posterior border of the ramus was left intact. In cases where teeth were in continuity with the lesion, they were extracted. In cases where cortical perforation occurred, any associated overlying mucoperiosteum was excised. All patients were reviewed annually for a follow-up period of 2 to 8 years. Results. All odontogenic keratocysts were found in the mandible. Of these, 23 were in the ramus and angular region (74.2%) and 8 were located in the body of the mandible. No recurrences of the operated odontogenic keratocysts were observed during the follow-up period. Conclusion. Our findings indicate that removal of odontogenic keratocysts by resection without continuity defects is a satisfactory method of treatment.

Growth, mineral acquisition, and water use by mycorrhizal wheat grown under water stress

Abstract: Plants colonized with arbuscular mycorrhizal (AM) fungi generally have greater growth and acquisition of mineral nutrients, and often have greater ability to withstand drought compared to nonmycorrhizal (nonAM) plants. This study determined effects of water stress (WS) versus no WS (nonWS) and the AM fungus Glomus monosporum (AM vs nonAM) on growth, acquisition of phosphorus (P), zinc (Zn), copper (Cu), manganese (Mn), and iron (Fe), and water use in two durum wheat (Triticum durum Desf.) cultivars exhibiting differences in resistance to WS. Plants were grown on soil [low P silty clay (Typic Xerochrept, pH=8.1)] and sand mixtures in a greenhouse. Shoot and root dry matter (DM), total root length (RL), and root colonization with AM for plants grown under non WS were higher than for plants grown under WS. Much of the reduction in DM was overcome by AM plants grown under WS. The ‘drought‐resistant’ wheat cultivar CR057 had higher AM root colonization than the ‘drought‐sensitive’ cultivar CR006 when ...

Benefit, cost and water-use efficiency of arbuscular mycorrhizal durum wheat grown under drought stress

Abstract: Arbuscular mycorrhizal fungi (AMF) living symbiotically with host plants enhance plant growth by improving the acquisition of mineral nutrients and water relations. This study determined the effects of AMF inoculation on growth, benefit/cost and water-use efficiency (grams dry matter produced per kilogram water evapotranspired) in two durum wheat genotypes (drought sensitive and drought tolerant) under water-stressed and well-watered conditions. Plants were grown in a low-P silty clay (Typic Xerochrept) soil mix in a greenhouse. Shoot and root dry matter (DM) and root AMF colonization were higher for well-watered than for water-stressed plants. The mycorrhizal plants were more water-use efficient than nonmycorrhizal plants. Shoot DM differences between mycorrhizal and nonmycorrhizal plants represent the benefit derived by plants from AMF-root associations. Shoot DM differences between mycorrhizal and nonmycorrhizal plants under similar conditions of water treatment represent the cost to the plant of AMF-root associations. Values of benefit/cost for AMF-root associations were highest when plants were water-stressed and decreased under well-watered conditions. Genotypic differences in calculated costs and benefits were pronounced. Benefit/cost analysis may be helpful in evaluating host plant genotypes in order to optimize efficiencies of AMF symbiosis under different environmental conditions.

Glazing and finishing dental porcelain: a literature review.

Abstract: Background Dental porcelain has found an increased number of applications in recent years with the development of new methods for the construction of porcelain veneers and intracoronal restorations. In addition, it is used in metal-ceramic and all-porcelain crowns and bridges for the restoration of anterior and posterior teeth. Methods This paper presents a review of a number of studies that have examined the visual and microscopic appearance and roughness of glazed, unglazed and polished porcelain surfaces using techniques such as, scanning electron microscopy and surface profilometry. Findings All have agreed that glazed porcelain provides a smooth and dense surface. Many have shown that polishing can produce an equally smooth surface, which may even be esthetically better. Some studies supported the use of polishing as an alternative to glazing. However, reports have shown that unglazed porcelain is more abrasive than glazed. Clinical significance This paper aims to guide general practitioners in the proper polishing of adjusted porcelain in the dental office. The recommendations of various authors are summarized in Table I.

A class of novel uniplanar series resonators and their implementation in original applications

Abstract: A class of novel millimetric uniplanar series resonators are presented, which can be used in monolithic and hybrid uniplanar microwave integrated circuits (MIC's). The proposed structures are able to demonstrate low radiation and compactness characteristics, which are attractive for passive and active monolithic and hybrid integrated circuits. A principle of achieving these high-quality circuits is described and also confirmed by experimental and theoretical results, which are in good agreement up to 50 GHz. To illustrate the features of the proposed series resonators and demonstrate their effectiveness, two classes of miniature coplanar waveguide (CPW) filters (namely, low-pass and bandpass) are designed using these resonators. The developed low-pass filter has some important advantages such as low insertion loss in passband, very wide stopband, high cutoff rates, small size, low number of elements, and an effective control of spurious signals. On the other hand, the newly developed bandpass filter provides an alternative, yet compact, structure to classical filters. Obviously, many other classes of filters or passive components can also be designed.

Oral manifestations of Ellis-van Creveld syndrome: report of two siblings with unusual dental anomalies.

Abstract: Ellis-van Creveld syndrome (EvC), also called chondroectodermal dysplasia, is a rare occurrence inherited as an autosomal recessive disease. Despite the fact that oral manifestations play an important role in the diagnosis criteria for EvC, few detailed reports have been published in the dental literature. This articles presents two siblings with EvC, a boy aged 9 years and a girl aged 7 1/2 years, a product of unaffected first cousin parents. The patients manifests: chondrodysplasia of tubular bones resulting in disproportionate dwarfism, polydactyly and syndactyly of hands and feet, severe dystrophic nails, multiple broad labial frenula with abnormal attachments, congenital missing incisors, anomalous teeth, bilateral partial clefts of the alveolar bone, and malocclusion. Other features noted in either cases are: congenital heart defect, median notch of the upper lip, shovel-shaped incisors and taurodontism. Of the unusual dental findings observed in our patients are talon cusp, reduced crown size, supernumerary tooth, and early eruption of teeth. Because half of the cases with EvC have cardiac malformation, dental treatment must be performed under prophylactic antibiotic coverage. Dentists play an important role in early diagnosis and control of dental problem of this condition.

Obesity in Jordan.

Abstract: OBJECTIVES: To study the prevalence of obesity among semi-urban communities in Jordan and its association with a number of factors. DESIGN: A sample of households was systematically selected from four Jordanian towns namely, Sarih, Sikhra, Southern Mazar and Subha-Subhieh. All subjects aged ≥25 y within the selected households, were invited to participate in the study. A total of 2836 subjects were actually included in the study, with an overall response rate of 70.5%. Study procedures were carried out in the local health centres in each town over a one-month period. RESULTS: The overall prevalence of obesity (body mass index, BMI≥30 kg/m2) was 49.7%; 32.7% in males and 59.8% in females. Obesity was more prevalent in the older age groups, illiterate people, diabetic and hypertensive subjects, and those with hypercholesterolaemia (HC), hypertriglyceridaemia (HTG), high level of low density lipoprotein cholesterol (LDL), and low level of high density lipoprotein cholesterol (HDL). After adjusting for age and gender, obesity was associated with diabetes mellitus (DM) (odds ratio (OR) 1.4, 95% confidence limit (CL) 1.1, 1.8), hypertension (HT) (OR 2.2, 95% CL 1.7, 2.8), HC (OR 1.3, 95% CL 1.1, 1.5), HTG (OR 2.3, 95% CL 2.0, 2.8), elevated LDL (OR 1.5, 95% CL 1.2, 1.8) and low HDL (OR 2.3, 95% CL 1.8, 2.9). CONCLUSION: Obesity seems to be a common disorder among adult Jordanians. More attention should be paid to this problem at the national level.

Prevalence of pulp stones in Jordanian adults

Abstract: Objective. The purpose of this study was to describe the prevalence of pulp stones in a sample of Jordanian dental patients. The article also presents frequency distributions of this condition among different types of teeth. Study design. Data were collected through radiographic examinations of a random sample of periapical and bitewing films of 4573 teeth from 814 dental records from the Faculty of Dentistry's filing system. Results. Pulp stones were identified in 22% of the teeth examined. First and second molars were the teeth most commonly affected. Pulp stone incidence was not significantly different among different age and gender groups.

Prevalence of taurodontism in Jordanian dental patients

Abstract: OBJECTIVES To assess the prevalence of taurodontism in a group of Jordanian adult dental patients. METHODS Posterior periapical radiographs of 875 unselected dental patients were examined for the presence of taurodontism defined as the presence of an apically displaced pulp chamber without the usual constriction at the cemento-enamel junction. RESULTS Taurodontism was detected in 8% of subjects and 4.4% of the teeth examined. The maxillary second molar was the most commonly affected tooth. It was equally distributed between males and females (7.9% compared with 8.1% respectively, P > 0.05). 26.7% of the taurodont teeth also had pulp stones or calcifications. CONCLUSION Taurodontism is not uncommon in Jordan but further larger scale studies are required to assess its prevalence in the general population to compare it with other ethnic groups.

Wastewater irrigation effect on soil, crop and environment : A pilot scale study at Irbid, Jordan

Abstract: An investigation was carried out at pilot scale to test the feasibility of using the effluent of a rotating biological contactors (RBC) unit treating wastewater generated from a university campus. The objective of the study was to cerefully monitor the impact of wastewater irrigation on the soil, percolating water, crop growth and the pathogenic condition within the immediate vicinity of wastewater application.

Seasonal mycorrhizal colonization of winter wheat and its effect on wheat growth under dryland field conditions

Abstract: A field experiment was conducted to determine the seasonal patterns of arbuscular mycorrhiza (AM) in a dryland winter wheat (Triticum aestivum L.) system and to determine wheat growth and P uptake responses to inoculation with mycorrhizal fungus. Broadcast-incorporated treatments included (1) no inoculation with mycorrhizal fungus, with and without P fertilizer, and (2) mycorrhizal fungal inoculation at a rate of 5000 spores of Glomus intraradices (Schenck and Smith), per 30 cm in each row, with and without fertilizer P. Winter wheat was seeded within a day after treatments were imposed, and roots were sampled at five growth stages to quantify AM. Shoot samples were also taken for determination of dry matter, grain yield and yield components, and N and P uptake. No AM infection was evident during the fall months following seeding, which was characterized by low soil temperature, while during the spring, the AM increased gradually. Increases in wheat grain yields by enhanced AM were of similar magnitude to the response obtained from P fertilization. However, responses differed at intermediate growth stages. At the tillering stage, P uptake was mainly increased by P fertilization but not by fungal inoculation. At harvest, enhanced AM increased P uptake regardless of whether or not fertilizer P was added. The AM symbiosis increased with rising soil temperatures in the spring, in time to enhance late-season P accumulation and grain production.

Assessment of aggression, sexual behavior and fertility in adult male rat following long-term ingestion of four industrial metals salts.

Abstract: 1. The effect of long-term ingestion of the industrial metals salts, manganese sulfate, aluminum chloride, lead acetate and copper chloride was investigated on aggression, sexual behavior and fertility in male rat. Adult male rats ingested solutions of these salts along with drinking water at a concentration of 1000 p.p.m. for 12 weeks. 2. Male rat sexual behavior was suppressed after the ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride. The ingestion of solutions of these salts markedly prolonged the intromission and ejaculation latencies. Aluminum chloride and copper chloride reduced the copulatory efficiency. 3. Male rat aggression was also abolished after the ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride. The ingestion of solutions of these salts markedly suppressed lateralizations, boxing bouts, fight with stud male and ventral presenting postures. 4. Fertility was reduced in male rats ingested with lead acetate. The total number of resorptions was increased in female rats impregnated by males ingested with manganese sulfate and lead acetate. 5. Body, absolute or relative testes, seminal vesicles weights were dropped in adult male rats ingested with manganese sulfate, aluminum chloride, lead acetate and copper chloride. However, the absolute or relative preputial gland weights were not affected. Collectively, these results suggest that the long-term ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride would have adverse effects on sexual behavior, territorial aggression, fertility and the reproductive system of the adult male rat.

Ultrastructural effects of date extract on Candida albicans

Abstract: The effect of Berhi date extract on the ultrastructure of Candida albicans was studied by scanning and transmission electron microscopy. Exposure of yeast to 5% (w/v) date extract showed evidence of weakening in the cell wall with indications of cell distortion and partial collapse in some cases as seen by scanning electron microscopy. Increasing the concentration of date extract (20%, w/v) led to more drastic damage to the yeast with cell lysis and concurrent leakage of cytoplasmic material with eventual cell death. Ultrastructural investigation showed irregular shapes of cells treated with date extract, with prominent effects on cell wall layers. Cell membranes lost their integrity, aggregation of the cytoplasmic contents and large detachment of plasmalemma from cell wall was observed in the treated cells. These results suggest that date extract may have multiple effects on Candida with an increasing potential of using it for prophylaxis purposes.