Thirty extracted mandibular premolars were randomly divided into 3 groups. Canals were cleaned, obturated and the teeth incubated. Guttapercha removal was performed using: Hedström files with xylene (Group 1); ProFile® alone (Group 2) and combination of both (Group 3). Time required to remove the gutta-percha was recorded. Postoperative radiographs were taken. Specimens were split longitudinally and photographed. Amount of gutta-percha left at coronal, middle and apical thirds was calculated by computer (QWIN software) and the photographs were also evaluated visually by two endodontists. Results showed that the combined technique was fastest in removing gutta-percha. Radiographically, more residual was left in Group 2. Although computer analysis also showed more residual was left in Group 2, they were in a small percentage and there were no significant differences (P>0.05, SPSS paired-samples T test) among groups. Although there were significant differences between the two evaluators in their scoring, both generally agreed (Kappa’s analysis= 0.64) there was more guttapercha residual in Group 2 compared to Group 3 in the apical thirds. Although the differences in efficacy of guttapercha removal among these techniques were not significant, the use of ProFile® increased the speed of the procedure. The combined technique showed the most superior efficacy in gutta-percha removal.
HbE/Beta thalassemia (HbE/β-thalassemia) is one of the common genetic disorders in South East Asia. It is heterogeneous in its clinical presentation and molecular defects. There are genetic modifiers which have been reported to influence the disease severity of this disorder. The aim of this study was to determine the genetic polymorphisms which were responsible for the disease clinical diversity. A case-control study was conducted among Malay transfusion-dependent HbE/β-thalassemia patients. Patients who were confirmed HbE/β-thalassemia were recruited and genotyping study was performed on these subjects. Ninety-eight patients were selected and divided into moderate and severe groups based on clinical parameters using Sripichai scoring system (based on hemoglobin level, spleen size, growth development, the age of first transfusion and age of disease presentation). Forty-three (44.9%) and 55 (56.1%) patients were found to have moderate and severe clinical presentation, respectively. Genotyping analysis was performed using Affymetrix 6.0 microarray platform. The SNPs were filtered using PLINK and Manhattan plot by R software. From the GWAS results, 20 most significant SNPs were selected based on disease severity when compared between moderate and severe groups. The significant SNPs found in this study were mostly related to thalassemia complications such as rs7372408, associated with KCNMB2-AS1 and SNPs associated with disease severity. These findings could be used as genetic predictors in managing patients with HbE/β-thalassemia and served as platform for future study.
BACKGROUND: The 10-item version of Perceived Stress Scale (PSS-10) is a widely used tool to measure stress. The Malay version of the PSS-10 has been validated among Malaysian Medical Students. However, studies have not been conducted to assess its validity in occupational settings.
AIM: The aim of this study is to assess the psychometric properties of the Malay version of the PSS-10 in two occupational setting in Malaysia.
SUBJECTS AND METHODS: This study was conducted among 191 medical residents and 513 railway workers. An exploratory factor analysis was performed using the principal component method with varimax rotation. Correlation analyses, Kaiser-Meyer-Olkin, Bartlett's test of Sphericity and Cronbach's alpha were obtained. Statistical analysis was carried out using statistical package for the social sciences version 16 (SPSS, Chicago, IL, USA) software.
RESULTS: Analysis yielded two factor structure of the Malay version of PSS-10 in both occupational groups. The two factors accounted for 59.2% and 64.8% of the variance in the medical residents and the railway workers respectively. Factor loadings were greater than 0.59 in both occupational groups. Cronbach's alpha co-efficient was 0.70 for medical residents and 0.71 for railway workers.
CONCLUSION: The Malay version of PSS-10 had adequate psychometric properties and can be used to measure stress among occupational settings in Malaysia.
KEYWORDS: Factor structure; Malaysia; Occupational; Perceived stress scale; Psychometric properties; Validity
Combined Support Vector Machine (SVM) and Principal Component Analysis (PCA) was used to recognize the infant cries with asphyxia. SVM classifier based on features selected by the PCA was trained to differentiate between pathological and healthy cries. The PCA was applied to reduce dimensionality of the vectors that serve as inputs to the SVM. The performance of the SVM utilizing linear and RBF kernel was examined. Experimental results showed that SVM with RBF kernel yields good performance. The classification accuracy in classifying infant cry with asphyxia using the SVM-PCA is 95.86%.
The skin of a fast swimming shark reveals riblet structures that help reduce the shark's skin friction drag, enhancing its efficiency and speed while moving in the water. Inspired by the structure of the shark skin denticles, our team has carried out a study as an effort in improving the hydrodynamic design of marine vessels through hull design modification which was inspired by this riblet structure of shark skin denticle. Our study covers on macroscaled design modification. This is an attempt to propose an alternative for a better economical and practical modification to obtain a more optimum cruising characteristics for marine vessels. The models used for this study are constructed using computer-aided design (CAD) software, and computational fluid dynamic (CFD) simulations are then carried out to predict the effectiveness of the hydrodynamic effects of the biomimetic shark skins on those models. Interestingly, the numerical calculated results obtained show that the presence of biomimetic shark skin implemented on the vessels give about 3.75% reduction of drag coefficient as well as reducing up to 3.89% in drag force experienced by the vessels. Theoretically, as force drag can be reduced, it can lead to a more efficient vessel with a better cruising speed. This will give better impact to shipping or marine industries around the world. However, it can be suggested that an experimental procedure is best to be conducted to verify the numerical result that has been obtained for further improvement on this research.
The thermoluminescence (TL) glow curves and kinetics parameters of Thulium (Tm) doped silica cylindrical fibers (CF) are presented. A linear accelerator (LINAC) was used to deliver high-energy radiation of 21MeV electrons and 10MV photons. The CFs were irradiated in the dose range of 0.2-10Gy. The experimental glow curve data was reconstructed by using WinREMS. The WinGCF software was used for the kinetic parameters evaluation. The TL sensitivity of Tm-doped silica CF is about 2 times higher as compared to pure silica CF. Tm-doped silica CF seems to be more sensitive to 21MeV electrons than to 10MV photons. Surprisingly, no supralinearity was displayed and a sub-linear response of Tm-doped silica CF was observed within the analyzed dose range for both 21MeV electrons and 10MV photons. The Tm-doped silica CF glow curve consists of 5 individual glow peaks. The Ea of peak 4 and peak 5 was highly dependent on dose when irradiated with photons. We also noticed that the electron radiation (21MeV) caused a shift of glow peak by 7-13°C to the higher temperature region compared with photons radiation (10MV). Our Tm-doped fibers seem to give high TL response after 21MeV electrons, which gives around 2 times higher peak integral as compared with 10MV photon radiation. We concluded that peak 4 is the first-order kinetic peak and can be used as the main dosimetric peak of Tm-doped silica CF.
Lithium potassium borate (LKB) glasses co-doped with TiO2 and MgO were prepared using the melt quenching technique. The glasses were cut into transparent chips and exposed to gamma rays of (60)Co to study their thermoluminescence (TL) properties. The TL glow curve of the Ti-doped material featured a single prominent peak at 230 °C. Additional incorporation of MgO as a co-activator enhanced the TL intensity threefold. LKB:Ti,Mg is a low-Z material (Z(eff)=8.89) with slow signal fading. Its radiation sensitivity is 12 times lower that the sensitivity of TLD-100. The dose response is linear at doses up to 10(3) Gy. The trap parameters, such as the kinetics order, activation energy, and frequency factor, which are related to the glow peak, were determined using TolAnal software.
The various technological advancements in computed tomography (CT) have resulted in remarkable growth in the use of CT imaging in clinical practice, not the least of which has been its establishment as the most valuable imaging examination for the assessment of cardiovascular system disorders. The objective of this study was to assess the effective radiation dose and radiation risk for patients during cardiac CT procedures, based on studies from four different hospitals equipped with 128 slice CT equipment. A total of eighty-three patients were investigated in this study with different clinical indications. Effective doses were also calculated using software based on Monte Carlo simulation. The mean patient age (years), weight (kg), and body mass index (BMI (kg/m2)) were 49 ± 11, 82 ± 12, and 31 ± 6, respectively. The results of the study revealed that the tube voltage (kVp) and tube current-exposure time product (mAs) ranged between 100 to 140 and 50 to 840 respectively. The overall average patient dose values for the volume CT dose index [(CTDIvol), in mGy)] and dose length product (DLP) (in mGy·cm) were 34.8 ± 15 (3.7-117.0) and 383.8 ± 354 (46.0-3277.0) respectively. The average effective dose (mSv) was 15.2 ± 8 (1.2-61.8). The radiation dose values showed wide variation between different hospitals and even within the same hospital. The results indicate the need to optimize radiation dose and to establish diagnostic reference levels (DRLs) for patients undergoing coronary computed tomography angiography (CCTA), also to harmonize the imaging protocols to ensure reduced radiation risk.
Patient radiation dose and image quality are primary issues in the conduct of nuclear medicine (NM) procedures. A range of protocols are currently used in image acquisition and analysis of quality control (QC) tests, with National Electrical Manufacturers Association (NEMA) methods and protocols widely accepted in providing an accurate description, measurement and report of γ-camera performance parameters. However, no standard software is available for image analysis. Present study compares vendor QC software analysis and three types of software freely downloadable from the internet: NMQC, NM Toolkit and ImageJ-NM Toolkit software. These were used for image analysis of QC tests of γ-cameras based on NEMA protocols including non-uniformity evaluation. Ten non-uniformity QC images were obtained using a dual head γ-camera installed in Trieste General Hospital and then analyzed. Excel analysis was used as the baseline calculation for the non-uniformity test according to NEMA procedures. The results of non-uniformity analysis showed good agreement between the independent types of software and Excel calculations (the average differences were 0.3%, 2.9%, 1.3% and 1.6% for the Useful Field of View (UFOV) integral, UFOV differential, Central Field of View (CFOV) integral and CFOV differential, respectively), while significant differences were detected following analysis using the company QC software when compared with Excel analysis (the average differences were 14.6%, 20.7%, 25.7% and 31.9% for the UFOV integral, UFOV differential, CFOV integral and CFOV differential, respectively). Compared to use of Excel calculations use of NMQC software was found to be in close accord. Variation in results obtained using the three types of software and γ-camera QC software was due to the use of different pixel sizes. It is important to conduct independent analyses tests in addition to using the vendor QC software in order to determine the differences between values.
One of the roles expected of dental personnel is to promote dental seeking behaviour to the public. It is to ensure that adults maintain an optimum number of teeth for overall health and quality of life by enabling them to eat, speak and socialise without pain, discomfort or embarrassment. The objective of this study was to determine the reasons for seeking dental care and the factors that influence this decision among adult patients. This was a retrospective study of clinical records among patients of 18 years old and above who attended Universiti Sains Islam Malaysia (USIM) Dental Polyclinic, an academic dental centre, for the first time from January 2015 to December 2016. Socio-demographic data on age, gender and occupation as well as the reason for the visit were retrieved from the clinical records. Analysis of data was conducted using SPSS software version 21.0 and the pvalue was set at p
Polymorphism in PAX9 (rs8004560), a gene responsible for craniofacial and tooth development, is often associated with Class II/Div2 malocclusion. This study aimed to detect the presence of PAX9 SNP (rs8004560) and to determine its genotype and allele distribution in Class II skeletal base malocclusion, contributed by retrognathic mandible, in the local Malaysian population. The association of PAX9 SNP (rs8004560) with Class II skeletal base malocclusion was also determined. A case control study was performed on 30 samples; 15 from Class II skeletal base malocclusion, and 15 from Class I skeletal base subject as control. Cephalometric measurements were performed prior to saliva samples collection. Genomic DNA was extracted from unstimulated saliva of all subjects, and the DNA was amplified using specific primers for marker rs8004560, followed by genotyping by sequencing. SHEsis online software was used to analyse Hardy-Weinberg Equilibrium (HWE) for cases and controls. Allelic and genotypic frequencies were compared between cases and controls. Significant difference in allele frequency was observed within the group whereby G allele was over-represented in the analysed population (p0.05). Although no genetic association between PAX9 SNP (rs8004560) with Class II skeletal base malocclusion was observed, significant difference in allele frequency observed might provide some indication in the involvement of PAX9 polymorphism in Class II skeletal base malocclusion contributed by retrognathic mandible. Further research utilising larger sample size will be required in order to determine the role of PAX9 gene in the aetiology of Class II skeletal base malocclusion observed in the local Malaysian population.
The purpose of this study was to determine the dimensional accuracy of the skull models produced by Rapid prototyping technology using stereolithography apparatus. Computed tomography images were captured from four dry normal adult human skulls. The resultant 2-D images were stored in Digital Imaging and Communications in Medicine (DICOM) format. The segmentation of the images was prepared in MIMICS software. The slice files were then exported to a stereolithography apparatus (SLA) to produce the replica of each skull. Eight linear measurements were repeatedly made between identified landmarks on each of the original skull and its replica model using an electronic digital calliper. Each of the linear measurements was repeated 5 times and the average was taken to determine the absolute difference and percent difference between the original skull and its replica model. The overall absolute difference between the four human adult skulls and its replica models was 0.23 mm with a standard deviation of 1.37 mm. The percent difference was 0.08% with a standard deviation of 1.25%. The degree of error established by this system seems affordable in clinical applications when these models are used in the field of dental surgery for surgical treatment planning.
The sample size calculation for a prevalence only needs a simple formula. However, there are a number of practical issues in selecting values for the parameters required in the formula. Several practical issues are addressed and appropriate recommendations are given. The paper also suggests the application of a software calculator that checks the normal approximation assumption and incorporates finite population correction in the sample size calculation.
This study was to investigate the association between functional dentition with inadequate calorie intake and underweight in elderly people living in “Pondok” in Kelantan. A cross-sectional study participated by 369 elderly people was carried out. A simple random sampling method was utilized for the selection of the subjects. Subjects were interviewed using a structured form to collect information about subjects’ demographic background and self-reported health status. The 24-hour recall method was used to provide information on the subject’s exact food intake during the previous 24 hours. Body mass index was calculated from subjects’ weight and height, followed by oral assessment. The “Nutrical Software” was used for nutrient calculation, followed by SPSS version 11.5 for data analysis. The response rate was 95.6%. Majority of the respondents were female (92.4%). The percentage of subjects who had inadequate calorie intake and underweight was 71.0% and 25.7% respectively. The percentage of edentulism was 81.0%. The proportion of elderly with compromised functional dentition was 48.2% and majority was edentate elderly without wearing any complete dentures or wearing defective dentures, 23.6% and 56.2% respectively, while 20.2% was dentate elderly. The odds of having inadequate calorie intake and getting underweight among elderly with a compromised functional dentition was 3.7 times and 42.0 times respectively, compared to elderly with a non-compromised functional dentition. There was a significant association between inadequate calorie intake and underweight with functional dentition among elderly living in “Pondok” in Kelantan.
Cephalometric analyses using computer software have more advantages than manual analyses. However, the software should be evaluated for the accuracy and reproducibility before it can be used. The aims of the present study were: 1) to compare the differences in accuracy and precision between utilizing scanned images and soft copy images with the software 2) to assess the reproducibility of software and manual cephalometric analyses. Fifteen cephalograms were selected randomly from the Record Unit, Hospital Universiti Sains Malaysia. All films had 10 fiducial points marked and were scanned at 75 dots per inch (dpi) and 300 dpi. Manual and digital measurements were compared to obtain magnification factors. Seven digital x-ray images of a caliper were taken. The mean differences were measured between the fixed caliper measurement and digital measurements. Subsequently, 37 cephalograms were traced manually and digitally with Computer-Assisted Simulation System for Orthognathic Surgery (CASSOS) software to assess its accuracy and reproducibility after applying the obtained magnification factor. Steiner analysis was utilized and T tests were used to evaluate the mean difference. P
Dentin morphology and the lesion found in dental caries have been studied for many years. It was first observed under optical microscopy, and later using electron microscopy. Confocal laser scanning microscopy (CLSM) applied with several fluorescent dyes such as alizarin red to see normal dentinal tubules. However, as far as authors aware, the CLSM studies of dentinal tubules in human caries using alizarin red is rare. The aim of this study is to examine histopathological and morphological changes in dentinal tubules of dentin caries stained with alizarin red using CLSM. Fifteen extracted carious teeth (premolar or molar) was collected and fixed in neutral formalin solution buffered with phosphate buffer, rinsed and stored in calcium free phosphate buffer saline (PBS) at 4°C. The specimens were dehydrated and embedded in resin. Longitudinal or cross sections were cut and polished and then stained with alizarin red S (100 μg/ml) in 0.5 M HCl solution for 24-48 hour at 37°C. After dehydration specimens were mounted on glass slide and examined under CLSM using epi-flourescent mode or transmission light mode with wave length of 512 nm. The images of dentinal tubules were taken serially and optimum images of three-dimensional structures were reconstructed using software of CLSM. Histopathological changes of dentinal tubules in human caries showed area of demineralized dentin, translucent zone, and normal area. The dentinal tubules were thin and had numerous branches. In conclusion, confocal microscopy revealed Study shows that confocal microscopy revealed histopathological changes in dentinal tubules affected by carious lesions.
Upon reviewing the literature, the prevalence of many systemic conditions such as diabetes,
hypertension, asthma and rheumatoid arthritis were reported to be high in Saudi Arabia. The relationship of these
conditions with tooth loss among Saudi population was not investigated. Therefore, the aim of the present study
is to explore the relationship between tooth loss and most common medical conditions among Saudi dental
patient. The study participants were 250 patients who were randomly selected from the College of Dentistry
database of King Saud bin Abdulaziz University for Health Sciences (KSAU-HS) in Riyadh, Saudi Arabia.
Participants were requested to answer self-administered questionnaires related to their demographic as well as
general health questions concerned to the presence of systemic medical conditions. Missing teeth were
determined after examining the orthopantogram radiographs and reviewing the Romexis and SALUD databases.
Descriptive statistics, independent t-test and linear multiple regression model were performed using SPSS
software. The mean number of missing teeth among the study population was 5.8 teeth per person. The mean
number of missing teeth was higher among subjects with diabetes, hypertension, rheumatoid arthritis,
cardiovascular diseases, or osteoporosis compared to healthy individuals. A multiple linear regression analysis
model revealed that diabetes, hypertension and rheumatoid were significant predictors of missing teeth among
Saudi population. These results highlight the importance of the effect of medical conditions on oral health.
Tele-rehabilitation is an alternative to the conventional rehabilitation service that helps patients in remote areas to access a service that is practical in terms of logistics and cost, in a controlled environment. It includes the usage of mobile phones or other wireless devices that are applied to rehabilitation exercises. Such applications or software include exercises in the form of virtual games, treatment monitoring based on the rehabilitation progress and data analysis. However, nowadays, physiotherapists use a default profiling setting for patients carrying out rehabilitation, due to lack of information. Medical Interactive Rehabilitation Assistant (MIRA) is a computer-based (virtual reality) rehabilitation platform. The profile setting includes: a level of difficulty, percentage of tolerance and maximum range. To the best of our knowledge, there is a lack of optimization in the parameter values setting of MIRA exergames that could enhance patients' performance. Generally, non-optimal profile setting leads to reduced effectiveness. Therefore, this study aims to develop a method that optimizes the profile setting of each patient according to the estimated (desired) optimal results. The proposed method is developed using unsupervised and supervised machine learning techniques. We use Self-Organizing Map (SOM) to cluster patient records into several distinct clusters. K-fold cross validation is applied to construct the prediction models. Classification And Regression Tree (CART) is utilized to predict the patient's optimal input setting for playing the MIRA games. The combination of these techniques seems to improve the efficiency of the standard (default) way in predicting the optimal settings for exergames. To evaluate the proposed method, we conduct an experiment with data collected from a rehabilitation center. We use three metrics to quantify the quality of the results: R-squared (R2), Mean Absolute Error (MAE) and Root Mean Square Error (RMSE). The results of experimental analysis demonstrate that the proposed method is effective in predicting the adequate parameter setting in MIRA platform. The method has potential to be implemented as an intelligent system for MIRA prediction in healthcare. Moreover, the method could be extended to similar platforms for which data is available to train our method on.
We propose a deadbeat controller for the control of pulsatile pump flow (Q(p) ) in an implantable rotary blood pump (IRBP). Noninvasive measurements of pump speed and current are used as inputs to a dynamical model of Q(p) estimation, previously developed and verified in our laboratory. The controller was tested using a lumped parameter model of the cardiovascular system (CVS), in combination with the stable dynamical models of Q(p) and differential pressure (head) estimation for the IRBP. The control algorithm was tested with both constant and sinusoidal reference Q(p) as input to the CVS model. Results showed that the controller was able to track the reference input with minimal error in the presence of model uncertainty. Furthermore, Q(p) was shown to settle to the desired reference value within a finite number of sampling periods. Our results also indicated that counterpulsation yields the minimum left ventricular stroke work, left ventricular end diastolic volume, and aortic pulse pressure, without significantly affecting mean cardiac output and aortic pressure.
Developing a software program to manage data in a general practice setting is complicated. Vision Integrated Medical System is an example of a integrated management system that was developed by general practitioners, within a general practice, to offer a user friendly system with multi tasking capabilities. The present report highlights the reasons behind the development of this system and how it can assist day to day practice.