ABSTRACT
NiTi arch wires are used widely in orthodontic treatment due to its superelastic and biocompatibility properties. In brackets configuration, the force released from the arch wire is influenced by the sliding resistances developed on the arch wire-bracket contact. This study investigated the evolution of the forces released by a rectangular NiTi arch wire towards possible intraoral temperature and deflection changes. A three dimensional finite element model was developed to measure the force-deflection behavior of superelastic arch wire. Finite element analysis was used to distinguish the martensite fraction and phase state of arch wire microstructure in relation to the magnitude of wire deflection. The predicted tensile and bending results from the numerical model showed a good agreement with the experimental results. As contact developed between the wire and bracket, binding influenced the force-deflection curve by changing the martensitic transformation plateau into a slope. The arch wire recovered from greater magnitude of deflection released lower force than one recovered from smaller deflection. In contrast, it was observed that the plateau slope increased from 0.66N/mm to 1.1N/mm when the temperature was increased from 26°C to 46°C.
Subject(s)
Dental Alloys/chemistry , Dental Stress Analysis , Nickel/chemistry , Orthodontic Wires , Titanium/chemistry , Elasticity , Finite Element Analysis , Materials Testing , Mechanical Phenomena , Models, Theoretical , Stress, Mechanical , Temperature , Tensile StrengthABSTRACT
This review covers several basic methodologies of surface treatment and their effects on titanium (Ti) implants. The importance of each treatment and its effects will be discussed in detail in order to compare their effectiveness in promoting osseointegration. Published literature for the last 18 years was selected with the use of keywords like titanium dental implant, surface roughness, coating, and osseointegration. Significant surface roughness played an important role in providing effective surface for bone implant contact, cell proliferation, and removal torque, despite having good mechanical properties. Overall, published studies indicated that an acid etched surface-modified and a coating application on commercial pure titanium implant was most preferable in producing the good surface roughness. Thus, a combination of a good surface roughness and mechanical properties of titanium could lead to successful dental implants.
Subject(s)
Dental Implants , Titanium/pharmacology , Animals , Humans , Surface PropertiesABSTRACT
The calcium ferrite nano-particles (CaFe2O4 NPs) were synthesized using a sol-gel method for targeted drug delivery application. The proposed nano-particles were initially prepared by mixing calcium and iron nitrates that were added with citric acid in order to prevent agglomeration and subsequently calcined at a temperature of 550°C to obtain small particle size. The prepared nanoparticles were characterized by using an XRD (X-ray diffraction), which revealed the configuration of orthorhombic structures of the CaFe2O4 nano-particles. A crystallite size of ~13.59 nm was obtained using a Scherer's formula. Magnetic analysis using a VSM (Vibrating Sample Magnetometer analysis), revealed that the synthesized particles exhibited super-paramagnetic behavior having magnetization saturation of approximately 88.3emu/g. Detailed observation via the scanning electron microscopy (SEM) showed the calcium ferrite nano-particles were spherical in shape.
Subject(s)
Calcium/chemistry , Dextrans/chemistry , Ferric Compounds/chemistry , Magnetite Nanoparticles/chemistry , Molecular Targeted Therapy/methods , Nanocapsules/chemistry , Materials Testing , Nanocapsules/ultrastructure , Particle Size , Phase TransitionABSTRACT
BACKGROUND: Monitoring treatment response to anti-tuberculous therapy remains unsatisfactory in resource-limited countries where sophisticated and expensive tests are not readily available. Sputum culture for mycobacterium is desirable, but not obtainable in many developing countries. Sputum acid-fast bacilli (AFB) smear alone can be misinterpreted in the presence of unviable bacilli or non-tuberculous mycobacteria. Hence the search for a cheaper but reliable monitoring tool, or a combination of several tools, continues. Interesting reports from studies in third world nations have considered weight gain/loss as one such monitoring tool. Since pulmonary tuberculosis is endemic in this country, we take the opportunity to evaluate weight gain and chest radiograph, compared to sputum AFB smear in monitoring patient's response. METHODS: This was a retrospective study of confirmed positive sputum AFB smear patients from January 1999 to December 2004 who attended the Chest Clinic at Hospital Tengku Ampuan Afzan, Kuantan, Malaysia. Data on weight, chest radiograph and sputum AFB smear from initiation of therapy to end of treatment and follow-up were collected and analyzed. RESULTS: 201 patients were included. At week-4 of anti-tuberculous treatment, only 14.7% had positive sputum smear. At completion of therapy 93.1% had improved chest radiographs. 90% had weight gain, 5% had weight loss and the remaining had no change in weight. Amongst patients with weight loss, there were no significant differences in the underlying illnesses (p=0.376), sputum smear at 4 weeks (p=0.697) and chest X-ray changes (p=0.731). Three patients who initially showed sputum smear conversion had reappearance of positive smear results towards the end of treatment. One of them was diagnosed as treatment failure while the other two remained well after discontinuation of therapy. CONCLUSION: Weight gain is very common among smear-positive tuberculosis patients after treatment even though weight gain does not correlate well with underlying disease, sputum conversion and chest X-ray changes. Reappearance of smear-positive sputum must be interpreted with caution and not to be regarded as treatment failure without other evidence.
Subject(s)
Sputum/microbiology , Tuberculosis, Pulmonary/diagnostic imaging , Tuberculosis, Pulmonary/microbiology , Adult , Female , Humans , Malaysia , Male , Middle Aged , Radiography, Thoracic , Retrospective Studies , Weight Gain , Young AdultABSTRACT
Renal injury is observed in 10 percent of cases of abdominal trauma, and the majority (80 percent to 90 percent) of these are attributable to blunt trauma. Intravenous urography and ultrasonography of the abdomen were previously the modalities of choice in the imaging of renal injuries. However, computed tomography (CT) is currently the imaging modality of choice in the evaluation of blunt renal injury, since it provides the exact staging of renal injuries. The purpose of this article is to describe the CT staging of renal injuries observed in blunt abdominal trauma based on the Federle Classification and the American Association for the Surgery of Trauma renal injury severity scale.
Subject(s)
Kidney/diagnostic imaging , Kidney/injuries , Tomography, X-Ray Computed/methods , Abdominal Injuries/diagnosis , Abdominal Injuries/diagnostic imaging , Adolescent , Adult , Child , Diagnostic Imaging/methods , Female , Hemorrhage/diagnosis , Hemorrhage/diagnostic imaging , Humans , Kidney/blood supply , Male , Wounds, Nonpenetrating/diagnosis , Wounds, Nonpenetrating/diagnostic imagingABSTRACT
Computed tomography (CT) is widely used in assessing clinically stable patients with blunt abdominal trauma. In these patients, liver is one of the commonest organs being injured and CT can accurately identify and assess the extent of the injury. The CT features of blunt liver trauma include laceration, subcapsular or parenchymal haematomas, active haemorrhage and vascular injuries. Widespread use of CT has notably influenced the management of blunt liver injury from routine surgical to nonsurgical management. We present pictorial illustrations of various liver injuries depicted on CT in patients with blunt trauma.
Subject(s)
Liver/injuries , Tomography, X-Ray Computed/methods , Wounds, Nonpenetrating/diagnostic imaging , HumansABSTRACT
Melioidosis is caused by Burkholderia pseudomallei, a Gram-negative bacillus. Melioidosis can affect many organs, including the prostate. However, prostatic abscess due to melioidosis is uncommon. We describe five cases of melioidosis with prostatic abscess. Four of five patients had diabetes mellitus and had more than one organ involvement. The diagnosis of prostatic abscess in our patients was only made with computed tomography of the abdomen and pelvis. None of our patients underwent surgical drainage and all remained well after treatment with antibiotics, except for one mortality secondary to severe septicaemia.
Subject(s)
Abscess/diagnosis , Melioidosis/diagnosis , Prostatic Diseases/diagnosis , Tomography, X-Ray Computed , Abscess/drug therapy , Adult , Anti-Bacterial Agents/therapeutic use , Diabetes Mellitus, Type 2/complications , Drug Therapy, Combination , Follow-Up Studies , Humans , Malaysia , Male , Medication Adherence , Melioidosis/drug therapy , Middle Aged , Prostatic Diseases/drug therapy , Recurrence , Risk FactorsABSTRACT
The purpose of this study is to optimize adsorption conditions of powdered alum sludge (PAS) as low-cost adsorbent for the removal of three P-species (ortho-P, poly-P and organic-P) from wastewater using the response surface methodology (RSM). Initially, RSM in the basis of a 3-variable Box-Behnken design was used to determine the effect of pH (from 4 to 7), PAS mass (from 0.1 to 0.5 g) and PAS particle size (from 125 to 420 microm) on the response levels (removal efficiencies of the three P-species). Three response surface quadratic models in terms of three factors were then obtained from an analysis of the experimental data using a SAS computer package. Thereafter, the effect of each of the parameters on P removal for each of the three species was examined using the three-dimensional response surface. All three parameters (pH, PAS mass and PAS particle size) had a significant effect on the removal of each of the P species. Finally, optimal conditions for P species removal were determined at which the P-removals of 99.8% (for ortho-P), 94.9% (for poly-P) and 94.8% (for organic-P) were achieved, respectively. The results derived from the verification experiments agreed with that predicted by the models, confirming the suitability of the established models and the success of RSM in optimizing the PAS adsorption conditions.
Subject(s)
Alum Compounds/chemistry , Combinatorial Chemistry Techniques/methods , Phosphorus Compounds/chemistry , Phosphorus Compounds/isolation & purification , Sewage/chemistry , Ultrafiltration/methods , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Adsorption , Algorithms , Quality ControlABSTRACT
In this paper, two laboratory-scale simulated reed beds were investigated for the purpose of assessing the feasibility and effectiveness of using dewatered alum sludge as a possible substrate for wastewater treatment reed bed systems. One horizontal subsurface flow setup and one vertical flow setup were used. The horizontal flow system was planted with Phragmites australis while the vertical flow system was left unplanted. Thus, the latter was more akin to a sand filter system, but was examined with the potential use as a planted vertical reed bed system. The influent source used was farmyard wastewater. It is expected that the present study will provide the basis for long-term and large-scale trials in realizing the concept of integrating "waste" into treatment processes. Results obtained so far have shown that the dewatered alum sludge holds great promise as a low-cost resource media for use in reed bed treatment systems. Appreciable and stable performance was obtained during the continuous operation at high hydraulic, organic and phosphorus loadings. In particular, both wetlands achieved over 90% phosphorus removal, reflecting the significant advantage of this novel approach over conventional reed bed treatment systems. However, extensive research into possible surface clogging and possible release of some substances from the sludge to the treated effluent is necessary to ensure reliability of the system. This will help to make the alum sludge-based reed bed environmentally and economically justifiable.
Subject(s)
Alum Compounds , Industrial Waste , Poaceae/metabolism , Waste Disposal, Fluid/methods , Animal Husbandry , Desiccation , Phosphates/analysis , Phosphates/metabolism , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/metabolism , Water PurificationABSTRACT
In the title centrosymmetric dinuclear complex, [Cu(2)(C(15)H(11)BrN(2)O(3)S)(2)(C(2)H(6)OS)(2)], the Cu(II) ion is N,O-chelated by a dianionic ligand, monocoordinated by the sulfonamide N atom of a symmetry-related ligand and coordinated by an O atom from a dimethyl sulfoxide ligand, forming a distorted square-planar coordination geometry.
ABSTRACT
The mol-ecules of the title compound, C(10)H(10)N(4)S, are linked by N-H(indole)â¯S hydrogen bonds to form a linear hydrogen-bonded chain. There are two independent mol-ecules in the asymmetric unit.
ABSTRACT
Susuk, or charm needles, are inserted and worn subcutaneously in the face and other parts of the body, as they are believed to enhance beauty and youth, and for many other reasons such as treatment of headache, aches and pains in the joints, back or abdomen. The practice of inserting susuk is a traditional belief, genuinely cultural and superstitious, and common in the south-east Asian region. We present 13 cases of susuk, which was found incidentally on the radiographs as the patients came for various types of treatment at our centre.
Subject(s)
Face , Foreign Bodies/diagnostic imaging , Mouth , Cosmetic Techniques , Face/diagnostic imaging , Humans , Malaysia , Medicine, Traditional , Mouth/diagnostic imaging , Needles , Radiography, Panoramic , Religion and MedicineABSTRACT
BACKGROUND: Smoking has been associated with increased risk of periodontitis. The aim of the present study was to compare the periodontal disease severity of adult heavy smokers and never-smokers referred for assessment and treatment of chronic periodontitis. METHODS: A random sample of patients with at least 20 teeth, stratified for smoking and age (5-year blocks, 35 to 55 years), was selected from an original referral population of 1,221 subjects with chronic adult periodontitis. Adequate records for 59 never-smokers and 44 subjects who smoked at least 20 cigarettes per day were retrieved. The percentage of alveolar bone support was measured from dental panoramic radiographs with a Schei ruler at x3 magnification with the examiner unaware of the smoking status. Probing depths at six sites per tooth were obtained from the initial consultation. RESULTS: There was no significant difference in age between groups. Smokers had fewer teeth (p<0.001), fewer shallow pockets (p<0.001) and more deep probing depths (p<0.001). The differences were greater in subjects 45 years of age and over. In this age group, smokers had approximately 13% more bone loss, 15% more pockets in the 4-6 mm category and 7% more pockets in the >/= 7 mm category than the never-smokers. CONCLUSIONS: This study confirmed that smokers had evidence of more severe periodontal disease than never-smokers. The differences increased with age confirming an exposure-related response.
Subject(s)
Periodontal Diseases/complications , Smoking/adverse effects , Adult , Age Factors , Alveolar Bone Loss/complications , Female , Humans , Male , Middle Aged , Periodontal Diseases/diagnostic imaging , Periodontal Pocket/complications , Radiography , Retrospective Studies , Severity of Illness IndexABSTRACT
The subjective quality of life (QOL) of diabetic patients on oral hypoglycaemics was compared to schizophrenic patients who were well controlled with their antipsychotic medications. This comparison was made using the generic quality of life questionnaire produced by the World Health Organization QOL (WHOQOL) group, namely the WHOQOL-100. Statistical analysis showed that there was no significant difference in the psychological well-being and level of independence between the two groups. However, such measures revealed that the most impaired aspect of well-being in the schizophrenic group was the social relationship. Subjective QOL assessment is able to reveal deficits or handicaps that are obscure and probably difficult to appreciate on objective social and clinical evaluation. Such findings are valuable in planning the rehabilitative need of schizophrenic patients in the community.
Subject(s)
Antipsychotic Agents/therapeutic use , Quality of Life , Schizophrenia/drug therapy , Adult , Chi-Square Distribution , Diabetes Mellitus/drug therapy , Diabetes Mellitus/psychology , Female , Humans , Hypoglycemic Agents/therapeutic use , Malaysia , Male , Sickness Impact ProfileABSTRACT
In confronting the advances in the new treatment for incurable illnesses there is an increasing need for doctors to be aware of their patients' cognition and feeling related to their quality of life (QOL). Recognizing this need the authors translated and pilot tested the WHOQOL-100, a genuinely international measure of QOL by the World Health Organization (quality of life group). The WHOQOL-100 Malay version was pilot tested on 50 healthy controls and 250 ill subjects, suffering from hypertension, diabetes mellitus, those suffering from both hypertension and ischaemic heart disease, epilepsy and schizophrenia. The results showed several unique features of the QOL, which were influenced by different types of illnesses. The information obtained is different and probably not observable from clinical consultations. This study will be an impetus for further studies using the WHOQOL-100 assessment tool in the local population.
ABSTRACT
The aim of this study was to find the dosage and pattern of neuroleptic drug utilisation for the treatment of acute schizophrenia in a general psychiatry ward. This is an uncontrolled study involving 112 schizophrenic inpatients. Patients' socio-demographic variables, the type and peak daily doses of neuroleptics prescribed to them were analysed. Chlorpromazine was the most commonly prescribed drug. The peak mean daily dose required by the patients was equivalent to 537 mg of chlorpromazine; and 400 to 600 mg/ day of chlorpromazine or its equivalent was generally sufficient to treat acute psychosis. The majority of the patients received neuroleptics within this dose range. Low potency drugs were prescribed in lower doses than high potency drugs. Patients treated with depot preparation tended to receive higher doses of medication than those prescribed oral medication alone. The doses of neuroleptics were significantly correlated with duration of admission.
Subject(s)
Antipsychotic Agents/administration & dosage , Schizophrenia/drug therapy , Acute Disease , Chlorpromazine/administration & dosage , Female , Humans , Male , Racial GroupsABSTRACT
The compliance with drug regimens and follow-up visits of 225 known cases of relapsed schizophrenia was assessed. About 27% of the patients met the criteria for good compliance. The compliance was found to be significantly related to the patients' view of usefulness of the medication, treatment duration of less than 5 years, dosage schedule of once or twice per day and the supervision of medication at home. Patients with poor compliance who were prescribed drug dosage of not more than twice per day throughout follow-up and underwent counseling to enhance treatment compliance had a significantly lower relapse rate than the controlled group at the end of 1 year of follow-up. The importance of family support and understanding patients' cultural background in ensuring good compliance was highlighted.
Subject(s)
Developing Countries , Patient Compliance , Schizophrenia/drug therapy , Adolescent , Adult , Female , Humans , Male , Middle Aged , Patient Education as Topic , Prognosis , Schizophrenia/physiopathology , Schizophrenic Psychology , Social SupportABSTRACT
Contrasting beliefs often make cooperation between folk healers and modern doctors seem impossible. In the field of mental health, where communication is of such central importance, better mutual understanding is especially desirable. After reviewing the complexities involved, the author makes some suggestions on how the two kinds of practitioner could help each other.