Medicine and Health Sciences Commons^™

Effects Of Different Denture Cleansers On The Tensile Bond Strength Of Denture Liners, Selda Keskin

The effect of two denture cleansers (Polident1 and Protefix1) on the tensile bond strength between four soft liner materials (Molloplast B1, Permaflex1, Sofreliner Tough Medium1, and GC Reline Soft1) and a conventional denture base resin was investigated. For each of the liner materials 35 test specimens were prepared according to test the requirements and assigned into seven groups (n¼5). Before tensile testing, five of the liner specimens were kept in water or soaked in two cleansing solutions during 2 and 7 d. Five other samples served as a control group subjected directly to tensile testing. The bond strength values were …

Tensile Bond Strength Of A Highly Cross-Linked Denture Tooth To The, Selda Keskin

This study compared tensile bond strengths between conventional compressionmolded heat (HC)-, auto (AP)-, and microwave-polymerized (MC) poly(methyl methacrylate)-based denture resins and a relatively new injection-molded, microwave-polymerized polyurethane based resin (MI) bonded to a highly cross-linked denture tooth. In the first part of the experiments, denture teeth were used as received. In the second part, they were treated with dichloromethane to see its effect on bonding of conventional denture bases (HCS and APS). Bond strength was tested in tension according to ADA specification No.15. The results showed that the HC group failed cohesively because of higher interface bonding (49.95 MPa) compared …

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) …

Gene Expression In Human Oral Squamous Cell Carcinoma Is Influenced By Risk Factor Exposure, Cheong S. C., Chandramouli G. V. R., Saleh A., Rosnah Binti Zain, Lau S. H., Sivakumaren S., Pathmanathan R., Prime S. S., Teo S. H., Patel V., Gutkind J. S.

Prof. Dr. Rosnah Binti Zain

Oral squamous cell carcinoma (OSCC) is a world health problem and is associated with exposure to different risk factors. In the west, smoking and alcohol consumption are considered to be the main risk factors whilst in India and southeast Asia, betel quid (BQ) chewing is predominant. In this study, we compared the gene expression patterns of oral cancers associated with BQ chewing to those caused by smoking using Affymetrix microarrays. We found that 281 genes were differentially expressed between OSCC and normal oral mucosa regardless of aetiological factors including MMP1, PLAU, MAGE-D4, GNA12, IFITM3 and NMU. Further, we identified 168 …

Numbness Of The Ear Following Inferior Alveolar Nerve Block: The Forgotten Complication, W.C. Ngeow, W. L. Chai

Wei Cheong Ngeow

This article presents a distant complication in the auricle following the administration of a standard inferior alveolar nerve block. The patient experienced profound numbness of the auricle on the ipsilateral side of the injection that lasted for about an hour following unintended injection to the auriculotemporal nerve.

Craniofacial Anthropometric Norms Of Malaysian Indians, W.C. Ngeow, S. T. Aljunid

Wei Cheong Ngeow

Objective: This study was done to establish the craniofacial anthropometric norms of the young adult (18-25 years) Malaysian Indian. Materials and Methods: The study group consisted of convenient samples of 100 healthy volunteers, with equal number of female and male subjects who had no history of mixed racial-parentage. Twenty-two linear measurements were taken twice from 28 landmarks over six craniofacial regions. The methodology and evaluation of indices of the craniofacial region was adapted from Hajnis et al. Results: The minimum measurements are always contributed by the female Indian except for the nose height (n-sn), (left) eye fissure length (ex-en), upper …

Cyp1a1, Gstm1 And Gstt1 Polymorphisms And Oral Cancer - Correlation With Patients' Status At 2-Year, Age Of Onset, Nodal Status, Tumor Size And Stage, Abraham M. T., Karen-Ng L. P., Ghani W. M. N., Rosnah Binti Zain, Raja-Latifah R. J., Cheong S. C.

Prof. Dr. Rosnah Binti Zain

Altered expression of xenobiotic enzymes such as CYP1A1, GSTM1 and GSTT1 has been reported in some malignant tumors including oral cancer. However, the correlation between these enzymes and clinicopathologic parameters has not been well documented. The aim of this study was to investigate the associations between CYP1A1, GSTM1 and GSTT1 polymorphisms with patients’ status at 2-year, age of onset, nodal status, tumor size and disease stage. A total of 195 oral cancer patients were included in this study. Peripheral blood was obtained from consented individuals and CYP1A1, GSTM1 and GSTT1 genotypes were determined using PCR and restriction enzyme digestion. Chi-square …

A Radiographic Study On The Visualization Of The Anterior Loop In Dentate Subjects Of Different Age Groups, W.C. Ngeow, D. D. Dionysius, H. Ishak, P. Nambiar

Wei Cheong Ngeow

The anterior loop is defined as where the mental neurovascular bundle crosses anterior to the mental foramen then doubles back to exit the mental foramen. It cannot be seen clinically but can be detected in 11-60% of panoramic radiographs. As this anatomical structure is important in determining the placement position of endosseous implants in the mandibular premolar region, a pilot study was undertaken to determine its visibility on dental panoramic radiographs in dentate subjects of various age groups. One or more anterior loops were visible in 39 (40.2%) radiographs encompassing 66 sites (34.4%). Interestingly, anterior loops were most commonly observed …

Craniofacial Anthropometric Norms Of Malays, W.C. Ngeow, S. T. Aljunid

Wei Cheong Ngeow

Introduction: This study was undertaken to establish the craniofacial anthropometric norms of young adult Malaysian Malays. Methods: The study group consisted of convenient samples of 100 healthy volunteers (aged 18-25 years), with an equal number of female and male subjects who had no history of mixed racial parentage. 22 linear measurements were taken twice from 22 landmarks over six craniofacial regions. Results: The Malays shared many similar sizes of measurements with the Singaporean Chinese. Their left eye fissure length and mouth width (ch-ch) were almost identical for both genders. However, Malay females had an upper lip height (sn-sto) (left) and …

A Finite Element Study Of The Multilayered Structured Dental Post, Ahmed A. Madfa

Ahmed A. Madfa

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) …

Effect Of Filler Incorporation On The Fracture Toughness Properties Of Denture Base Poly(Methyl Methacrylate), Nidal Elshereksi

Nidal Elshereksi

Poly(methyl methacrylate) (PMMA) is the material of choice for denture base construction. In spite of its many good qualities, the application of PMMA as an ideal dental base material is still restricted by a few limitations. One of these is the difficulty in achieving intrinsic radiopacity in the material. The aim of the present study is to investigate the possibility of using barium titanate (BaTiO3) as a radiopacifier in PMMA. The formulation used in this study composed of PMMA 89.5 wt%, BaTiO3 10 wt% and benzoyl peroxide (BPO) 0.5 wt% as an initiator, methyl methacrylate (MMA) 90 wt% as a …

Effect Of Filler Incorporation On The Fracture Toughness Properties Of Denture Base Poly(Methyl Methacrylate), Nidal Elshereksi

Nidal Elshereksi

Poly(methyl methacrylate) (PMMA) is the material of choice for denture base construction. In spite of its many good qualities, the application of PMMA as an ideal dental base material is still restricted by a few limitations. One of these is the difficulty in achieving intrinsic radiopacity in the material. The aim of the present study is to investigate the possibility of using barium titanate (BaTiO3) as a radiopacifier in PMMA. The formulation used in this study composed of PMMA 89.5 wt%, BaTiO3 10 wt% and benzoyl peroxide (BPO) 0.5 wt% as an initiator, methyl methacrylate (MMA) 90 wt% as a …

Metastatic Follicular Thyroid Carcinoma To The Mandible: A Case Report, Ismail , S. B., Abraham T. , M., Zaini , Z. B., Yaacob , H. B., Rosnah Binti Zain

Prof. Dr. Rosnah Binti Zain

Introduction: Metastatic lesions to the oro-facial region may be the first evidence of dissemination of an unknown tumour from its primary site. Case presentation: We described a case of metastatic follicular thyroid carcinoma to the mandible presenting with pain and loosening of teeth in a 70 years old female patient leading to extraction of the loose teeth. Conclusion: The present case emphasizes the importance of considering metastasis in the differential diagnosis of swelling related to loosening of teeth, even though the patient had no history of any malignant disease.

Mdm2 Snp309 Does Not Confer An Increased Risk To Oral Squamous Cell Carcinoma But May Modulate The Age Of Disease Onset, Hamid S., Yang Y. H., Peng K. N. L., Ismail S. M., Rosnah Binti Zain, Lim K. P., Wan Mustafa W. M., Abraham M. T., Teo S. H., Cheong S. C.

Prof. Dr. Rosnah Binti Zain

The MDM2 SNP309 has been associated with increased expression of the protein which could suppress p53 function, and has been shown to modulate risk to cancer. We have previously shown that overexpression of MDM2 is a common event in oral cancers. In the present study, we determined the association between the MDM2 SNP309 polymorphism and oral cancer in 207 oral cancer patients and 116 normal subjects. We genotyped the MDM2 SNP309 by PCR-RFLP. Logistic regression was adapted to calculate odds ratios for MDM2 SNP309 polymorphism from univariate and multivariable adjusted models. Our results suggest that MDM2 SNP309 does not confer …

Intracanal Bisphosphonate Does Not Inhibit Replacement Resorption Associated With Delayed Replantation Of Monkey Incisors, Thong Y. L., Messer H. H., Rosnah Binti Zain, Saw L. H., Yoong L. T.

Prof. Dr. Rosnah Binti Zain

Progressive replacement resorption following delayed replantation of avulsed teeth has proved to be an intractable clinical problem. A wide variety of therapeutic approaches have failed to result in the predictable arrest of resorption, with a good long-term prognosis for tooth survival. Bisphosphonates are used in the medical management of a range of bone disorders and topically applied bisphosphonate has been reported to inhibit root resorption in dogs. This study evaluated the effectiveness of a bisphosphonate (etidronate disodium) as an intracanal medicament in the root canals of avulsed monkey teeth, placed before replantation after 1 h of extraoral dry storage. Incisors …

Gstm1, Gstt1 And Cyp1a1 Polymorphisms And Risk Of Oral Cancer: A Case-Control Study In Jakarta, Indonesia, Amtha R., Ching C. S., Rosnah Binti Zain, Razak I. A., Basuki B., Roeslan B. O., Gautama W., Purwanto D.

Prof. Dr. Rosnah Binti Zain

Purpose: to investigate genetic polymorphisms in GSTM1, GSTT1 and CYP1A1 and the association with the risk of oral cancer in the Jakarta population. Method: A total of 81 cases and 162 controls matched for age and sex were selected from 5 hospitals in Jakarta. Sociodemographic data using questionnaires were obtained and peripheral blood samples were collected with informed consent for PCR-RFLP assay. Conditional logistic regression analysis was performed to obtain the association between the risk of oral cancer and GSTM1, GSTT1 and CYP1A1 polymorphisms. Results: GSTM1 and GSTT1 null were slightly overrepresented among cases (60.5% and 45.7% respectively) compared to …

The Current Status Of The Case Report: Terminal Or Viable, Noor Hayaty Abu Kasim Abu Kasim N.H.

Noor Hayaty Abu Kasim Abu Kasim N.H.

The case report, which has a long history in medicine, has seen its fortune wax and wane with time. We discuss the challenges facing the continued survival of the case report, including the inability of journals to cope with the increased load and increased cost of publication, ethical issues, the impact factor and the rise of evidence-based medicine. We highlight the important role that the case report will continue to play in medical research and education, as a means of sharing information and detecting novelty through observations. Most importantly, the case report serves as a stepping stone for young physicians …