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Full-Text Articles in Oral Biology and Oral Pathology

Performance Of Melamine Modified Urea-Formaldehyde Microcapsules In A Dental Host Material, Noor Hayaty Abu Kasim Abu Kasim N.H. Nov 2011

Performance Of Melamine Modified Urea-Formaldehyde Microcapsules In A Dental Host Material, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Urea-formaldehyde (UF) microcapsules filled with dicyclopentadiene (DCPD) show potential for making self-healing dental restorative materials. To enhance the physical properties of the capsules, the urea was partially replaced with 0-5% melamine. The microcapsules were analyzed by different microscopic techniques. DSC was used to examine the capsule shell, and the core content was confirmed by (1)H NMR spectroscopy. Capsules in the range of 50-300 mu m were then embedded in a dental composite matrix consisting of bisphenol-A-glycidyl dimethacrylate (Bis-GMA) and triethylene-glycol dimethacrylate (TEGDMA). Flexural strength, microhardness, and nanoindentation hardness measurements were performed on the light-cured specimens. Optical microscopy (OM) examination showed …


Human Platelet Lysate Permits Scale-Up Of Dental Pulp Stromal Cells For Clinical Applications, Noor Hayaty Abu Kasim Abu Kasim N.H. Nov 2011

Human Platelet Lysate Permits Scale-Up Of Dental Pulp Stromal Cells For Clinical Applications, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Background aims. Dental pulp stromal cells (DPSC) are considered to be a promising source of stem cells in the field of regenerative therapy. However, the usage of DPSC in transplantation requires large-scale expansion to cater for the need for clinical quantity without compromising current good manufacturing practice (cGMP). Existing protocols for cell culturing make use of fetal bovine serum (FBS) as a nutritional supplement. Unfortunately, FBS is an undesirable additive to cells because it carries the risk of transmitting viral and prion diseases. Therefore, the present study was undertaken to examine the efficacy of human platelet lysate (HPL) as a …


Development Of Craniofacial Implants Produced By Metal Injection Molding Of Titanium Alloy Using Novel Binder System Based On Palm Oil, Noor Hayaty Abu Kasim Abu Kasim N.H. Oct 2011

Development Of Craniofacial Implants Produced By Metal Injection Molding Of Titanium Alloy Using Novel Binder System Based On Palm Oil, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Metal Injection Molding (MIM) is a cost-effective technique for producing small, complex, precision parts in high volumes. MIM consists of four main processing steps: mixing, injection molding, debinding and sintering. In the mixing step, the powder titanium alloy (Ti6Al4V) medical grade is mixed with a binder system based on palm stearin to form a homogeneous feedstock. The rheological studies of the feedstock have been determined properly in order to success during injection into injection molding machine. After molding, the binder holds the particles in place. The binder systems then have to be removed completely through debinding step. Any contamination of …


Porosity Reduction Model In Titanium - Hydroxyapatite Fgm Composites Using Shrinkage Measurement, Noor Hayaty Abu Kasim Abu Kasim N.H. Aug 2011

Porosity Reduction Model In Titanium - Hydroxyapatite Fgm Composites Using Shrinkage Measurement, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

A multilayered titanium (Ti)‐hydroxyapatite (HA) functionally graded material was produced via pressureless sintering at 1100°C. The initial and final porosities were determined via shrinkage measurements. The final porosity verification was carried out by the Archimedes method. The experimental porosity measurements were compared with two proposed models. The macroscopic and microstructure features and the measured porosities confirmed that the volume fraction porosity was associated with both matrix and reinforcing particles in all cases. The percolation threshold was observed at x = 0·75 in the xTi+(1−x)HA mixture.


Sociodemographic Characteristics, Clinicopathological Parameters And Survival Among Malaysians With Oral Squamous Cell Carcinoma (Oscc), Ghani W. M. N., Rosnah Binti Zain, Jalil N., Razak I. A., Raja-Latifah R. J., Samsuddin A. R. Jul 2011

Sociodemographic Characteristics, Clinicopathological Parameters And Survival Among Malaysians With Oral Squamous Cell Carcinoma (Oscc), Ghani W. M. N., Rosnah Binti Zain, Jalil N., Razak I. A., Raja-Latifah R. J., Samsuddin A. R.

Prof. Dr. Rosnah Binti Zain

Introduction: Western researchers showed that oral squamous cell carcinoma (OSCC) patients exhibit lower survival rate and poorer prognosis compared to other type of cancer where several clinicopathological parameters have been implicated in the survival of patients. This study aims to assess the association between sociodemographic and clinicopathological parameters with survival of OSCC patients. Method: Data were collected from 253 histologically diagnosed OSCC patients attending selected clinics nationwide. Survival was analyzed for relation with habits, site, disease stage and nodal involvement. Results: Mean age was 58.9 ± 12.6 years with 8.3% aged less than 40. Majority is females (61.1%) and of …


Mdm2 Splice Variants In Oral Cancer, Rosnah Binti Zain Jul 2011

Mdm2 Splice Variants In Oral Cancer, Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: MDM2 is a negative regulator of the p53 tumor suppressor protein. The presence of a variety of MDM2 splice variants have been reported in many different types of tumor and some have been shown to be associated with patient prognosis.Materials and methods: In this study, we demonstrated the occurrence of MDM2 splice variants in OSCC tissues. RNA was extracted from 45 OSCC tissues and 17 normal oral mucosa tissues and reverse transcribed into cDNA. Nested PCR was performed to amplify the MDM2 transcripts and the PCR amplicons were cloned into cloning vector pTZ57R/T and sequenced.Results: We demonstrated that 37/45 …


Microrna Profiles Of Oral Squamous Cell Carcinoma (Oscc) Using Formalin-Fixed, Paraffin Embedded (Ffpe) Tissue, Siow M. Y., Ng L. P. K., Abraham M. T., Zaini Z. M., Cheong S. C., Rosnah Binti Zain Jul 2011

Microrna Profiles Of Oral Squamous Cell Carcinoma (Oscc) Using Formalin-Fixed, Paraffin Embedded (Ffpe) Tissue, Siow M. Y., Ng L. P. K., Abraham M. T., Zaini Z. M., Cheong S. C., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: MicroRNAs (miRNAs) have previously found to be highly tissue- or disease-specific biomarkers with clinical applicability. However, the role of miRNAs in OSCC progression has yet to be well-studied. Here, we demonstrated the use of FFPE specimens in microarray profiling and quantitative real-time PCR (qPCR) approaches to identify miRNAs that are differentially expressed in OSCC compared with non-tumour tissues.Materials and methods: Four OSCC and four non-tumour FFPE tissues were obtained from the Malaysian Oral Cancer Database and Tumour System (MOCDTBS), coordinated by OCRCC-UM and profiled using Agilent 8 × 15 k mammalian miRNA microarray. Based on microarray results, TaqMan miRNA …


Immunohistochemical Features Of Extra-Nodal Nk/T Cell Lymphoma, Muhamad H. M., Ibrahim N. I., Rosnah Binti Zain Jul 2011

Immunohistochemical Features Of Extra-Nodal Nk/T Cell Lymphoma, Muhamad H. M., Ibrahim N. I., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

NK/T cell lymphoma is a destructive extranodal lymphoproliferative disorder of a putative natural killer (NK) cell lineage. This rare malignant lymphoma is difficult to diagnose due to the histological resemblance to reactive processes hence was once considered as an inflammatory lesion known as lethal midline granuloma or non-healing granuloma. Providentially, the advance in immunophenotyping has permit characterization of NK/T-cell lymphoma, as a distinct entity from other type of lymphoma. It is most commonly involved the nasal cavity, paranasal sinuses and hard palate and as the case we reported here of a NK/T-cell lymphoma in a 29 year old Indonesian man …


High Throughput Mutational Profiling Of Signaling Molecules In Oral Cancer, Zanaruddin , S. N. S., Cheong , S. C., Rahman , Z. A. A., Abd Ghani , W. M. N. W, Mustafa , W. M. W., Rosnah Binti Zain, Kong , Y. H., Hor , S. Y., Teo , S. H. Jul 2011

High Throughput Mutational Profiling Of Signaling Molecules In Oral Cancer, Zanaruddin , S. N. S., Cheong , S. C., Rahman , Z. A. A., Abd Ghani , W. M. N. W, Mustafa , W. M. W., Rosnah Binti Zain, Kong , Y. H., Hor , S. Y., Teo , S. H.

Prof. Dr. Rosnah Binti Zain

It is well established that a plethora of mutations that occur in oncogenes and tumor-suppressor genes are the main drivers of tumorigenesis. The identification of these mutations provides important clues to the cellular processes of carcinogenesis and affords an opportunity for these genes to be used for diagnostic and therapeutic purposes. In comparison to cancers such as breast, lung and colorectal, there is a lack of systematic, large scale characterization of oncogenic mutations oralsquamous cell carcinoma (OSCC).


Genome Wide Profiling Of Tongue And Cheek Cancer Using High Resolution Array Based Cgh, Chong V. K. V., Rahman Z. A. A., Zakaria Z., Tay K. K., Ismail S. M., Rosnah Binti Zain Jul 2011

Genome Wide Profiling Of Tongue And Cheek Cancer Using High Resolution Array Based Cgh, Chong V. K. V., Rahman Z. A. A., Zakaria Z., Tay K. K., Ismail S. M., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: Tongue and cheek cancer have different behaviors. In order to understand these behaviors, there is a need to look into the chromosomal alterations and gene pathways that maybe associated with oral cancer at these sites. Therefore, the objective of this study is to determine the differences in chromosomal aberrations and gene pathways involved in tongue and cheek cancer using high resolution array CGH. Methods: A genome wide screening with array CGH (SurePrint G3 CGH 1x1M microarray) was performed using gDNA from 20 snap frozen fresh tissues consisting of 12 tongue and 8 cheek oral squamous cell carcinomas (samples from …


Expression Of Gna12 And Its Role In Oral Cancer, Gan C. P., Rosnah Binti Zain, Abraham M. T., Patel V., Gutkind J. S., Cheong S. C., Chong C. E., Hamid S., Teo S. H. Jul 2011

Expression Of Gna12 And Its Role In Oral Cancer, Gan C. P., Rosnah Binti Zain, Abraham M. T., Patel V., Gutkind J. S., Cheong S. C., Chong C. E., Hamid S., Teo S. H.

Prof. Dr. Rosnah Binti Zain

Introduction: The variability of clinical outcomes in oral cancer patients and the heterogeneity of the disease are the main challenges for the improvement of current treatment modalities. Efforts in our laboratory have focused on the molecular profiling of oral cancer to understand the mechanisms underlying the disease. In a previous microarray study, we found Guanine nucleotide binding protein alpha-12 (GNA12) to be up-regulated in oral cancer. Materials and methods: In this study, we validated the expression of GNA12 at the mRNA level in 47 oral squamous cell carcinoma (OSCC) and 18 non-malignant oral mucosa tissues, by quantitative polymerase chain reaction …


Dietary Consumptions Pattern And Risk Of Oral Cancer: A Malaysian Scenario, Helen-Ng L. C., Ishak I. A., Ghani W. M. N., Marhazlinda J., Norlida A., Rosnah Binti Zain Jul 2011

Dietary Consumptions Pattern And Risk Of Oral Cancer: A Malaysian Scenario, Helen-Ng L. C., Ishak I. A., Ghani W. M. N., Marhazlinda J., Norlida A., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: The risk of cancer has been extensively investigated with the intake of single food items but food consumption in an individual is usually complex, made up by combinations of different food items. This study aims to identify dietary patterns of Malaysians, and establishing relationship between dietary pattern and oral cancer risk. Methods A hospital-based, case-control study was conducted on 300 Malaysians who seek treatment at participating hospitals between January 2003 and December 2010. The subjects consisted of 150 cases and 150 controls that were matched for gender, age (5 years) and ethnicity. Dietary intake was measured using Food Frequency …


Effects Of Smoking On Oral Cancer Transcriptome, Rosnah Binti Zain, Karen-Ng L. P., Cheong S. C., Anwar A., Mustaffa W. M. W., Prepagaran N., Zaini Z., Merican A. F., Abraham M. T., Tay K. K., Rahman Z. A. A., Jallaludin A. Jul 2011

Effects Of Smoking On Oral Cancer Transcriptome, Rosnah Binti Zain, Karen-Ng L. P., Cheong S. C., Anwar A., Mustaffa W. M. W., Prepagaran N., Zaini Z., Merican A. F., Abraham M. T., Tay K. K., Rahman Z. A. A., Jallaludin A.

Prof. Dr. Rosnah Binti Zain

Introduction: Oral cancer is a debilitating disease and the survival rates for these patients have not improved over the past decades. Tobacco smoking is one of the most common risk factor associated with oral cancer. Objectives: To explore and identify differential genes expression associated with tobacco smoking. Methodology: Next generation sequencing using the Illumina Genome Analyzer was done to sequence five fresh frozen oral cancer tissue samples from smoking patients, two of which were former smoker and an additional 8 samples consisting of normal oral mucosal tissues from the alveolar mucosa of non-cancer patients where 4 were smokers and another …


Combined Effects Of Isothiocyanates (Itcs) Intake, Glutathione S-Transferases (Gsts) Polymorphism And Risk Habits On Oral Squamous Cell Carcinoma (Oscc) Associated With Earlier Age Of Disease Onset, Karen-Ng L. P., Marhazlinda J., Rahman Z. A. A., Abraham M. T., Cheong S. C., Rosnah Binti Zain Jul 2011

Combined Effects Of Isothiocyanates (Itcs) Intake, Glutathione S-Transferases (Gsts) Polymorphism And Risk Habits On Oral Squamous Cell Carcinoma (Oscc) Associated With Earlier Age Of Disease Onset, Karen-Ng L. P., Marhazlinda J., Rahman Z. A. A., Abraham M. T., Cheong S. C., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: ITCs found in cruciferous vegetables has been reported to reduce cancer risk by inducing phase II conjugating enzymes, in particular GSTs. Interestingly, these enzymes also metabolize ITCs therefore; the protective effects of ITCs would depend on the activity of GSTs. This study aimed to determine association between dietary ITCs, GSTs polymorphisms and risk habits (cigarette smoking, alcohol drinking and betel-quid chewing) with oral cancer.Method: Included in this study were 115 OSCC patients and 116 healthy subjects. Information on ITC intake from cruciferous vegetables was collected via a semi-quantitative FFQ. Peripheral blood lymphocytes were obtained for genotyping of GSTM1, GSTT1 …


Association Between Retinol And Vitamin C With The Risk Of Oral Cancer - A Case-Control Study, Vimmitra A., Razak I. A., Helen-Ng L. C., Ghani W. M. N., Abdullah N., Rosnah Binti Zain Jul 2011

Association Between Retinol And Vitamin C With The Risk Of Oral Cancer - A Case-Control Study, Vimmitra A., Razak I. A., Helen-Ng L. C., Ghani W. M. N., Abdullah N., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: Dietary intake has been hypothesized to be associated with various diseases including oral cancer. According to studies worldwide, imbalanced diet and nutrient deficiency have been attributed to promote oral malignancies. However, the function of specific nutrients in preventing oral cancer remains largely undefined. This study aims to investigate the association between intake of retinol and vitamin C with the risk of oral cancer. Materials and methods: Dietary intake data was collected from 8 participating hospitals throughout Malaysia using a validated foodfrequency questionnaire (FFQ). Intake of retinol and vitamin C were computed using the Nutriemart software. This case-control study included …


Differentiation Of Dental Pulp Stem Cells Into Islet-Like Aggregates, Noor Hayaty Abu Kasim Abu Kasim N.H. May 2011

Differentiation Of Dental Pulp Stem Cells Into Islet-Like Aggregates, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

The post-natal dental pulp tissue contains a population of multipotent mesenchymal progenitor cells known as dental pulp stromal/stem cells (DPSCs), with high proliferative potential for self-renewal. In this investigation, we explored the potential of DPSCs to differentiate into pancreatic cell lineage resembling islet-like cell aggregates (ICAs). We isolated, propagated, and characterized DPSCs and demonstrated that these could be differentiated into adipogenic, chondrogenic, and osteogenic lineage upon exposure to an appropriate cocktail of differentiating agents. Using a three-step protocol reported previously by our group, we succeeded in obtaining ICAs from DPSCs. The identity of ICAs was confirmed as islets by dithiozone-positive …


A Simple Technique For Chromosome Preparation From Embryonic Tissues Of Teleosts For Ploidy Verification, Pradeep P. J., Srijaya T. C., Rosnah Binti Zain, Papini A., Chatterji A. K. Apr 2011

A Simple Technique For Chromosome Preparation From Embryonic Tissues Of Teleosts For Ploidy Verification, Pradeep P. J., Srijaya T. C., Rosnah Binti Zain, Papini A., Chatterji A. K.

Prof. Dr. Rosnah Binti Zain

The modified preparation technique developed in the present study has provided an excellent chromosome metaphase spread from the whole body of larvae of the red hybrid tilapia Oreochromis mossambicus (Peters, 1852) X Oreochromis niloticus (Linnaeus, 1758). Unlike other chromosome preparation methods, this modified technique showed a reduction in cell loss while suspending cells during the dropping process. This modified technique can therefore be widely applied not only to various tilapias but also to other teleostean fishes for preparing chromosome spreads. The best treatment parameters for preparing good chromosome spreads from red hybrid tilapia were optimized as 0.01% concentration of colchicine …


Structural And Compositional Characterization Of Silverfil Amalgam, Noor Hayaty Abu Kasim Abu Kasim N.H. Mar 2011

Structural And Compositional Characterization Of Silverfil Amalgam, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

SilverFil (Silverfildental Products, Malaysia) is another commercially available dental amalgam; however it is based on silver and mercury only. It is claimed that upon amalgamation, there is no excess mercury in SilverFil. Objectives: The objectives of this study were to determine the structural state and chemical composition of the starting materials and presence of mercury in the resulting amalgam. Methods: All the starting materials of SilverFil and the SilverFil amalgam specimens were characterize using Field Emission Scanning Electron Microscopy (FESEM-EDX), X-Ray Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS). Results: The FESEM images of the amalgam shows silver-mercury (Ag-Hg) clusters. The …


Valproic Acid: Growth Inhibition Of Head And Neck Cancer By Induction Of Terminal Differentiation And Senescence, Gan C. P., Hamid S., Hor S. Y., Rosnah Binti Zain, Ismail S. M., Mustafa W. M. W., Teo S. H., Saunders N., Cheong S. C. Jan 2011

Valproic Acid: Growth Inhibition Of Head And Neck Cancer By Induction Of Terminal Differentiation And Senescence, Gan C. P., Hamid S., Hor S. Y., Rosnah Binti Zain, Ismail S. M., Mustafa W. M. W., Teo S. H., Saunders N., Cheong S. C.

Prof. Dr. Rosnah Binti Zain

Background: There are limited studies on the effects of drugs that modulate epigenetic regulation for head and neck squamous cell carcinoma (HNSCC). This study determined the effect of valproic acid (VPA) on HNSCC. Methods: Growth inhibition effects of VPA alone or in combination with 5-aza-2'deoxycytidine (5-aza-dC) or all-trans retinoic acid (ATRA) was evaluated with MTT and clonogenic assays on 5 HNSCC cell lines. The mechanism of growth inhibition was investigated by looking at markers of terminal differentiation and senescence. Results: Growth inhibition profiles of HNSCC cell lines varied in response to VPA. Inhibition of clonogenic survival in response to VPA …


Intercountry Prevalences And Practices Of Betel-Quid Use In South, Southeast And Eastern Asia Regions And Associated Oral Preneoplastic Disorders: An International Collaborative Study By Asian Betel-Quid Consortium Of South And East Asia, Lee C. H., Ko A. M. S., Warnakulasuriya S., Yin B. L., Rosnah Binti Zain, Ibrahim S. O., Liu Z. W., Li W. H., Zhang S. S., Utomo B., Rajapakse P. S., Warusavithana S. A., Abdul Razak I., Abdullah N., Shrestha P., Kwan A. L., Shieh T. Y., Chen M. K., Ko Y. C. Jan 2011

Intercountry Prevalences And Practices Of Betel-Quid Use In South, Southeast And Eastern Asia Regions And Associated Oral Preneoplastic Disorders: An International Collaborative Study By Asian Betel-Quid Consortium Of South And East Asia, Lee C. H., Ko A. M. S., Warnakulasuriya S., Yin B. L., Rosnah Binti Zain, Ibrahim S. O., Liu Z. W., Li W. H., Zhang S. S., Utomo B., Rajapakse P. S., Warusavithana S. A., Abdul Razak I., Abdullah N., Shrestha P., Kwan A. L., Shieh T. Y., Chen M. K., Ko Y. C.

Prof. Dr. Rosnah Binti Zain

Health risks stemming from betel-quid (BQ) chewing are frequently overlooked by people. Updated epidemiological data on the increased BQ use among Asian populations using comparable data collection methods have not been widely available. To investigate the prevalence, patterns of practice and associated types of oral preneoplastic disorders, an intercountry Asian Betel-quid Consortium study (the ABC study) was conducted for Taiwan, Mainland China, Malaysia, Indonesia, Nepal and Sri Lanka. A random sample of 8,922 subjects was recruited, and the data were analyzed using survey-data modules adjusted for the complex survey design. Chewing rates among men (10.7-43.6%) were significantly higher than women …


Human Platelet Lysate Permits Scale-Up Of Dental Pulp Stromal Cells For Clinical Applications, Govindasamy V., Ronald V. S., Abdullah A. N. B., Ganesan Nathan K. R., Aziz Z. A. C. A., Abdullah M., Rosnah Binti Zain, Kasim N. H. A., Musa S., Bhonde R. R. Jan 2011

Human Platelet Lysate Permits Scale-Up Of Dental Pulp Stromal Cells For Clinical Applications, Govindasamy V., Ronald V. S., Abdullah A. N. B., Ganesan Nathan K. R., Aziz Z. A. C. A., Abdullah M., Rosnah Binti Zain, Kasim N. H. A., Musa S., Bhonde R. R.

Prof. Dr. Rosnah Binti Zain

Background aims. Dental pulp stromal cells (DPSC) are considered to be a promising source of stem cells in the field of regenerative therapy. However, the usage of DPSC in transplantation requires large-scale expansion to cater for the need for clinical quantity without compromising current good manufacturing practice (cGMP). Existing protocols for cell culturing make use of fetal bovine serum (FBS) as a nutritional supplement. Unfortunately, FBS is an undesirable additive to cells because it carries the risk of transmitting viral and prion diseases. Therefore, the present study was undertaken to examine the efficacy of human platelet lysate (HPL) as a …


Advancing Oral Medicine Through Informatics And Information Technology: A Proposed Framework And Strategy, Rosnah Binti Zain Jan 2011

Advancing Oral Medicine Through Informatics And Information Technology: A Proposed Framework And Strategy, Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

The implementation of information technology in healthcare is a significant focus for many nations around the world. However, information technology support for clinical care, research and education in oral medicine is currently poorly developed. This situation hampers our ability to transform oral medicine into a 'learning healthcare discipline' in which the divide between clinical practice and research is diminished and, ultimately, eliminated. This paper reviews the needs of and requirements for information technology support of oral medicine and proposes an agenda designed to meet those needs. For oral medicine, this agenda includes analyzing and reviewing current clinical and documentation practices, …


Optimization Of Microencapsulation Process For Self-Healing Polymeric Material, Noor Hayaty Abu Kasim Abu Kasim N.H. Jan 2011

Optimization Of Microencapsulation Process For Self-Healing Polymeric Material, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

A series of poly(urea-formaldehyde) (PUF) microcapsules filled with dicyclopentadiene (DCPD) was successfully prepared by in situ polymerization. The effect of diverse process parameters and ingredients on the morphology of the microcapsules was observed by SEM, optical microscopy (OM) and digital microscopy. Different techniques for the characterization of the chemical structure and the core content were considered such as FT-IR and (1)H-NMR as well as the characterization of thermal properties by DSC. High yields of free flowing powder of spherical microcapsules were produced. The synthesized microcapsules can be incorporated into another polymeric host material. In the event the host material cracks …


Thermo-Mechanical Stress In Multilayered Dental Post Due To Temperature Gradient, Noor Hayaty Abu Kasim Abu Kasim N.H. Sep 2010

Thermo-Mechanical Stress In Multilayered Dental Post Due To Temperature Gradient, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Objective: To analyse thermo-mechanical stress in endodontically treated teeth restored with Multilayered Structured Dental Posts (MSDPs) under cold and hot conditions using Finite Element Analysis (FEM). Methods: Three MSDPs of multilayer design of xTi-yHA composition added to a zirconia layer (model A), an alumina layer (model B) and a titanium layer (model C) were compared with zirconia (model D) and titanium (model E) posts. The fractions of Ti and HA was varied gradually. Changes in temperature of an endodontically restored tooth model were calculated as a result of hot and cold response. The resulting thermo-mechanical stresses were analysed and compared …


Genetic Polymorphisms And Risk Of Oral Cancer, Zaini Z. M., Karen-Ng L. P., Cheong S. C., Gurdeep S. M., Yuen K. M., Tay K. K., Jalil N., Ismail S. M., Jallaluddin A., Rosnah Binti Zain Sep 2010

Genetic Polymorphisms And Risk Of Oral Cancer, Zaini Z. M., Karen-Ng L. P., Cheong S. C., Gurdeep S. M., Yuen K. M., Tay K. K., Jalil N., Ismail S. M., Jallaluddin A., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Objectives: This study was done to investigate the role of single nucleotide polymorphisms(SNPs) within genes of phase I (CYP1A1) and phase II (GSTM1, GSTT1,GSTP1) of the xenobiotic metabolism and its association with oral cancer risk.Methods: An unmatched case-control study was conducted using 207 newly diagnosed oral cancer patients and 117 non-cancer subjects selected from the OCRCC database. Peripheral blood was obtained from consented individuals and the CYP1A1, GSTM1, GSTT1 and GSTP1 genotypes were determined using polymerase chain reaction (PCR) and restriction enzyme digestion (RFLP). Simple and multiple logistic regression yielding odds ratio (OR and aOR) were employed to measure the …


Transcriptional Profiling Of Oral Squamous Cell Carcinoma Using Formalin-Fixed Paraffin-Embedded Samples, Saleh A., Rosnah Binti Zain, Hussaini H., Ng F., Tanavde V., Hamid S., Chow A. T., Lim G. S., Abraham M. T., Teo S. H., Cheong S. C. May 2010

Transcriptional Profiling Of Oral Squamous Cell Carcinoma Using Formalin-Fixed Paraffin-Embedded Samples, Saleh A., Rosnah Binti Zain, Hussaini H., Ng F., Tanavde V., Hamid S., Chow A. T., Lim G. S., Abraham M. T., Teo S. H., Cheong S. C.

Prof. Dr. Rosnah Binti Zain

Despite the advances in cancer treatment, the 5-year survival rate for oral cancer has not changed significantly for the past 40 years and still remains among the worst of all anatomic sites. Gene expression microarrays have been used successfully in the identification of genetic alterations in cancer development, however, these have hitherto been limited by the need for specimens with good quality intact RNA. Here, we demonstrated the use of formalin-fixed paraffin-embedded tissues in microarray experiments to identify genes differentially expressed between cancerous and normal oral tissues. Forty-three tissue samples were macrodissected and gene expression analyses were conducted using the …


A Bootstrap-Anfis Framework For Oral Cancer Prognosis Based On Clinical And Genomic Markers, Chang S. W., Sameem A. K., Rosnah Binti Zain, Merican A. F. M. A. Jan 2010

A Bootstrap-Anfis Framework For Oral Cancer Prognosis Based On Clinical And Genomic Markers, Chang S. W., Sameem A. K., Rosnah Binti Zain, Merican A. F. M. A.

Prof. Dr. Rosnah Binti Zain

The incidence of oral cancer is high in Malaysia especially for those of Indian ethnic origin. In this research, an oral cancer prognosis prediction model will be developed by using Bootstrap-ANFIS techniques. The aim of this research is to improve the prediction of oral cancer survival and to identify the key clinical and genomic markers for the survival prediction of oral cancer. The proposed model is designed to handle small medical dataset with limitations in terms of time, cost and tissue samples.


Cytotoxicity Of Polyurethane Dimethacrylate Derived From Palm Oil Polyol., Noor Hayaty Abu Kasim Abu Kasim N.H. Jan 2010

Cytotoxicity Of Polyurethane Dimethacrylate Derived From Palm Oil Polyol., Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Objective: The aim of this study was to investigate the cytotoxicity effect of polyurethane dimethacrylate monomer derived from palm oil polyol (PUDMA) and 2 experimental composite resins based on these monomer PUDMA- based composites) compared to an experimental Bis-GMA/TEGDMA-based composite and EsthetX flowable composite (Dentsply, Caulk, USA). Methods: The experimental composite resins were prepared by mixing 0.25% and 0.75% by weight camphorquinone and ethyl (4-dimethyl amino) benzoate with 60% filler for each of the following monomer systems; I) PUDMA monomer (PUDMA-based composite resin), II) Bis-GMA/TEGDMA at ratio of 75:25 by weight, III) PUDMA/BisGMA-TEGDMA at ratio of 50:50 by weight. Eight …


Surface Reproduction Of Elastomeric Materials: Viscosity And Groove Shape Effects, Noor Hayaty Abu Kasim Abu Kasim N.H. Jan 2010

Surface Reproduction Of Elastomeric Materials: Viscosity And Groove Shape Effects, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Objective: To evaluate the effect of viscosity and type of grooves on surface detail reproduction of elastomeric impression materials. Methods: Express putty/light-, Impregum medium- and heavy/light-bodied and Aquasil medium- and putty/light-bodied elastomeric impression materials were chosen for this study. Five impressions were made using a cylindrical aluminum reference block with U- and V- shaped grooves and to produce 35 master dies. Each master die was immersed in distilled water at 370 C for 5 minutes prior to the impression making on moist surfaces. Surface topography of the dies and impressions were captured using Alicona Imaging System. The mean difference in …


A Finite Element Study Of The Multilayered Structured Dental Post, Noor Hayaty Abu Kasim Abu Kasim N.H. Sep 2009

A Finite Element Study Of The Multilayered Structured Dental Post, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

Ideally, dental post should have stiffness that is similar to the crown at the coronal part and stiffness similar to the dentine at the apical part. This will reduce stress concentration at either coronal or the apical parts of the dentine and minimize the chance of interfacial loosening and enhance the reliability of post. Objective: To investigate the biomechanical behaviour of Multilayered Structured Dental Posts (MSDPs) using finite element analysis (FEA). Methods: Two models of MSDPs consist of multilayer design of xTi-yHA composition added to a zirconia layer (model A) and the same compositions added to alumina layer (model B) …