Displaying publications 81 - 100 of 117 in total

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  1. Sharif R, Chong KH, Zakaria NH, Ong ML, Reilly JJ, Wong JE, et al.
    J Phys Act Health, 2016 11;13(11 Suppl 2):S201-S205.
    PMID: 27848721 DOI: 10.1123/jpah.2016-0404
    BACKGROUND: The 2016 Malaysia Active Healthy Kids Report Card aims to collect, assess, and grade current and comprehensive data on physical activity (PA) and associated factors in Malaysian children and adolescents aged 5 to 17 years.
    METHODS: This report card was developed following the Active Healthy Kids Canada Report Card protocol. The Research Working Group identified the core matrices, assessed the key data sources, and evaluated the evidence gathered for grade assignments. A grade was assigned to each indicator by comparing the best available evidence against relevant benchmark using a standardized grading scheme.
    RESULTS: Overall Physical Activity, Active Transportation, and Sedentary Behavior were assigned the D grade. The lowest grade of F was assigned to Diet, while School and Government Strategies and Investments were graded higher with a B. Five indicators were assigned INC (incomplete) due to a lack of representative data.
    CONCLUSIONS: The report card demonstrates that Malaysian children and adolescents are engaging in low levels of PA and active commuting, high levels of screen time, and have extremely low compliance with dietary recommendations. More efforts are needed to address the root causes of physical inactivity while increasing the opportunities for children and adolescents to be more physically active.
    MESH: screen time
  2. Rozali M.N., Wahid F.H., John J., Purmal K.
    Ann Dent, 2017;24(1):27-32.
    MyJurnal
    The objectives of the study were to determine the normal dental arch width of Malays, their correlation with
    the facial framework and the ideal size of orthodontic impression trays that fit the dental arch. Eighteen adult
    Malays with normal Class I occlusion were evaluated. Arch width was measured on each subject’s dental
    cast. Direct anthropometric measurements were taken for 8 facial landmarks. Orthodontic impression trays
    were tried on each subject’s dental cast to determine the best fitting tray. Correlations analysis was made
    between the arch widths and the best fitting impression trays used and also with various craniofacial
    anthropometric measurements. The eight measurements from the craniofacial region were compared
    with the maxillary and mandibular intercanine, interpremolar and intermolar widths. In the maxillary arch,
    there were significant correlation between the face width and the interpremolar and intermolar widths
    respectively, while in the mandibular arch, significant correlations were noted between the mandible depth
    and the interpremolar and intermolar widths respectively. The most common fitting impression tray was size
    6 for the upper jaw and size 5 for the lower jaw. There was a significant correlation between the maxillary
    intercanine width and the size of the impression trays. The significant correlation between upper and lower
    interpremolar and intermolar widths and the anthropometric measurements of this Malay population may
    assist in predicting arch expansion to achieve Class 1 occlusion during orthodontic or maxillofacial surgical
    treatment. The significant correlation between the upper intercanine width and the size of impression tray
    can be a useful parameter when determining the size of impression tray.
  3. Leder K, Openshaw JJ, Allotey P, Ansariadi A, Barker SF, Burge K, et al.
    BMJ Open, 2021 01 08;11(1):e042850.
    PMID: 33419917 DOI: 10.1136/bmjopen-2020-042850
    INTRODUCTION: Increasing urban populations have led to the growth of informal settlements, with contaminated environments linked to poor human health through a range of interlinked pathways. Here, we describe the design and methods for the Revitalising Informal Settlements and their Environments (RISE) study, a transdisciplinary randomised trial evaluating impacts of an intervention to upgrade urban informal settlements in two Asia-Pacific countries.

    METHODS AND ANALYSIS: RISE is a cluster randomised controlled trial among 12 settlements in Makassar, Indonesia, and 12 in Suva, Fiji. Six settlements in each country have been randomised to receive the intervention at the outset; the remainder will serve as controls and be offered intervention delivery after trial completion. The intervention involves a water-sensitive approach, delivering site-specific, modular, decentralised infrastructure primarily aimed at improving health by decreasing exposure to environmental faecal contamination. Consenting households within each informal settlement site have been enrolled, with longitudinal assessment to involve health and well-being surveys, and human and environmental sampling. Primary outcomes will be evaluated in children under 5 years of age and include prevalence and diversity of gastrointestinal pathogens, abundance and diversity of antimicrobial resistance (AMR) genes in gastrointestinal microorganisms and markers of gastrointestinal inflammation. Diverse secondary outcomes include changes in microbial contamination; abundance and diversity of pathogens and AMR genes in environmental samples; impacts on ecological biodiversity and microclimates; mosquito vector abundance; anthropometric assessments, nutrition markers and systemic inflammation in children; caregiver-reported and self-reported health symptoms and healthcare utilisation; and measures of individual and community psychological, emotional and economic well-being. The study aims to provide proof-of-concept evidence to inform policies on upgrading of informal settlements to improve environments and human health and well-being.

    ETHICS: Study protocols have been approved by ethics boards at Monash University, Fiji National University and Hasanuddin University.

    TRIAL REGISTRATION NUMBER: ACTRN12618000633280; Pre-results.

  4. EAS Familial Hypercholesterolaemia Studies Collaboration, Vallejo-Vaz AJ, Akram A, Kondapally Seshasai SR, Cole D, Watts GF, et al.
    Atheroscler Suppl, 2016 Dec;22:1-32.
    PMID: 27939304 DOI: 10.1016/j.atherosclerosissup.2016.10.001
    The potential for global collaborations to better inform public health policy regarding major non-communicable diseases has been successfully demonstrated by several large-scale international consortia. However, the true public health impact of familial hypercholesterolaemia (FH), a common genetic disorder associated with premature cardiovascular disease, is yet to be reliably ascertained using similar approaches. The European Atherosclerosis Society FH Studies Collaboration (EAS FHSC) is a new initiative of international stakeholders which will help establish a global FH registry to generate large-scale, robust data on the burden of FH worldwide.
  5. John J, Ann Mani S, Palaniswamy K, Ramanathan A, Razak AA
    J Prosthodont, 2015 Apr;24(3):233-8.
    PMID: 24976147 DOI: 10.1111/jopr.12191
    PURPOSE: The purpose of this preliminary study was to evaluate the flexural properties of poly(methyl methacrylate) (PMMA) reinforced with oil palm empty fruit bunch (OPEFB) fiber.

    MATERIALS AND METHODS: The flexural strength and flexural modulus of three OPEFB fiber-reinforced PMMA were compared with a conventional and a commercially available reinforced PMMA. The three test groups included OPEFB fibers of 0.5 mm thickness, 2.0 mm thickness, and OPEFB cellulose.

    RESULTS: All test group specimens demonstrated improved flexural strength and flexural modulus over conventional PMMA. Reinforcement with OPEFB cellulose showed the highest mean flexural strength and flexural modulus, which were statistically significant when compared to the conventional and commercially reinforced PMMA used in this study. OPEFB fiber in the form of cellulose and 0.5 mm thickness fiber significantly improved flexural strength and flexural modulus of conventional PMMA resin. Further investigation on the properties of PMMA reinforced with OPEFB cellulose is warranted.

    CONCLUSIONS: Natural OPEFB fibers, especially OPEFB in cellulose form, can be considered a viable alternative to existing commercially available synthetic fiber reinforced PMMA resin.

  6. Wafa SW, Hamzaid H, Talib RA, Reilly JJ
    J Trop Pediatr, 2014 Apr;60(2):161-3.
    PMID: 24213306 DOI: 10.1093/tropej/fmt093
    The present study examined objectively measured physical activity in Malaysian children and compared the differences in physical levels between obese and healthy weight children. Eighty-six obese children were matched for age and sex with 86 healthy weight children with median age 9.5 years. Habitual physical activity and sedentary behaviour were measured over 5 days using Actigraph accelerometers. Time spent sedentary was significantly higher in the obese group (90% vs. 86% of daytime; p = 0.001). Moderate-to-vigorous-intensity physical activity was significantly higher in the healthy weight group (1.2 vs. 0.7% of daytime, p < 0.001). In both healthy weight and obese children, physical activity levels were exceptionally low, although moderate-to-vigorous-intensity physical activity was significantly lower in the obese group than the healthy weight group. Efforts to prevent and treat obesity in Malaysian children will need a substantial focus on the promotion of reductions in sedentary behaviour and increases in physical activity.
  7. Wafa SW, Talib RA, Hamzaid NH, McColl JH, Rajikan R, Ng LO, et al.
    Int J Pediatr Obes, 2011 Jun;6(2-2):e62-9.
    PMID: 21604965 DOI: 10.3109/17477166.2011.566340
    CONTEXT: Few randomized controlled trials (RCTs) of interventions for the treatment of childhood obesity have taken place outside the Western world.
    AIM: To test whether a good practice intervention for the treatment of childhood obesity would have a greater impact on weight status and other outcomes than a control condition in Kuala Lumpur, Malaysia.
    METHODS: Assessor-blinded RCT of a treatment intervention in 107 obese 7- to 11-year olds. The intervention was relatively low intensity (8 hours contact over 26 weeks, group based), aiming to change child sedentary behavior, physical activity, and diet using behavior change counselling. Outcomes were measured at baseline and six months after the start of the intervention. Primary outcome was BMI z-score, other outcomes were weight change, health-related quality of life (Peds QL), objectively measured physical activity and sedentary behavior (Actigraph accelerometry over 5 days).
    RESULTS: The intervention had no significant effect on BMI z score relative to control. Weight gain was reduced significantly in the intervention group compared to the control group (+1.5 kg vs. +3.5 kg, respectively, t-test p < 0.01). Changes in health-related quality of life and objectively measured physical activity and sedentary behavior favored the intervention group.
    CONCLUSIONS: Treatment was associated with reduced rate of weight gain, and improvements in physical activity and quality of life. More substantial benefits may require longer term and more intensive interventions which aim for more substantive lifestyle changes.
  8. Mwase-Vuma TW, Janssen X, Okely AD, Tremblay MS, Draper CE, Florindo AA, et al.
    J Sci Med Sport, 2022 Dec;25(12):1002-1007.
    PMID: 36270900 DOI: 10.1016/j.jsams.2022.10.003
    OBJECTIVES: To validate parent-reported child habitual total physical activity against accelerometry and three existing step-count thresholds for classifying 3 h/day of total physical activity in pre-schoolers from 13 culturally and geographically diverse countries.

    DESIGN: Cross-sectional validation study.

    METHODS: We used data involving 3- and 4-year-olds from 13 middle- and high-income countries who participated in the SUNRISE study. We used Spearman's rank-order correlation, Bland-Altman plots, and Kappa statistics to validate parent-reported child habitual total physical activity against activPAL™-measured total physical activity over 3 days. Additionally, we used Receiver Operating Characteristic Area Under the Curve analysis to validate existing step-count thresholds (Gabel, Vale, and De Craemer) using step-counts derived from activPAL™.

    RESULTS: Of the 352 pre-schoolers, 49.1 % were girls. There was a very weak but significant positive correlation and slight agreement between parent-reported total physical activity and accelerometer-measured total physical activity (r: 0.140; p = 0.009; Kappa: 0.030). Parents overestimated their child's total physical activity compared to accelerometry (mean bias: 69 min/day; standard deviation: 126; 95 % limits of agreement: -179, 316). Of the three step-count thresholds tested, the De Craemer threshold of 11,500 steps/day provided excellent classification of meeting the total physical activity guideline as measured by accelerometry (area under the ROC curve: 0.945; 95 % confidence interval: 0.928, 0.961; sensitivity: 100.0 %; specificity: 88.9 %).

    CONCLUSIONS: Parent reports may have limited validity for assessing pre-schoolers' level of total physical activity. Step-counting is a promising alternative - low-cost global surveillance initiatives could potentially use pedometers for assessing compliance with the physical activity guideline in early childhood.

  9. Ali PS, John J, Selvaraj M, Kek TL, Salleh MZ
    Microbiol. Immunol., 2015 May;59(5):299-304.
    PMID: 25753649 DOI: 10.1111/1348-0421.12253
    Nodamura virus (NoV) B2, a suppressor of RNA interference, binds double stranded RNAs (dsRNAs) and small interfering RNAs (siRNAs) corresponding to Dicer substrates and products. Here, we report that the amino terminal domain of NoV B2 (NoV B2 79) specifically binds siRNAs but not dsRNAs. NoV B2 79 oligomerizes on binding to 27 nucleotide siRNA. Mutation of the residues phenylalanine49 and alanine60 to cysteine and methionine, respectively enhances the RNA binding affinity of NoV B2 79. Circular dichroism spectra demonstrated that the wild type and mutant NoV B2 79 have similar secondary structure conformations.
  10. Mani SA, Naing L, John J, Samsudin AR
    Int J Paediatr Dent, 2008 Sep;18(5):380-8.
    PMID: 18284472 DOI: 10.1111/j.1365-263X.2007.00890.x
    BACKGROUND: Numerous methods of age estimation have been proposed. The Demirjian method is the most frequently used, which was first applied in a French Canadian population in 1973. The Willems method is a modification of the above and was applied in a Belgian population in 2002.
    OBJECTIVES: The objectives of this study were to test the applicability of the two methods, namely Demirjian and Willems, for age estimation in a Malay population, and to find the correlation between body mass index and the difference between the dental age and the chronological age.
    MATERIALS AND METHODS: A cross-sectional study involving 214 boys and 214 girls, selected by a simple stratified random sampling method was carried out. The orthopantomograph was used to score the seven left mandibular teeth, and the calculated maturity score was used to obtain the Demirjian dental age. Willems dental age was estimated using the tables proposed in the Willems method. Results. The Demirjian method overestimated the age by 0.75 and 0.61 years, while the Willems method overestimated the age by 0.55 and 0.41 years among boys and girls, respectively. In boys, the body mass index was significantly correlated to the difference in age using the Willems method.
    CONCLUSION: Further modification of either method is indicated for dental age estimation among the Malay population.
  11. Paramasvaran S, Krishnasamy M, Lee HL, John J, Lokman H, Naseem BM, et al.
    Trop Biomed, 2005 Dec;22(2):191-4.
    PMID: 16883287 MyJurnal
    A survey for small mammal parasites carried out in a secondary forest of Ulu Gombak, Selangor, Peninsula Malaysia yielded the following animals: Rattus bowersi (7), Rattus tiomanicus jalorensis (2), Maxomys rajah (12), Maxoyms whiteheadi (3), Leopoldamys sabanus(13), Sundamys muelleri(10), Lariscus insignis (1), Sundasciurus tenuis (1) and Tupaia glis (2). The following nematodes: Capillaria hepatica, Hepatojarakus malayae, Trichostrongylus sp. and Streptopharagus sp., the following cestodes: Hymenolepis sp., Raillietina sp. and Taenia taeniaformis; and trematode, Zonorchis sp. from Tupaia glis were recovered. No parasites were observed during blood examination. No endoparasite was seen in Maxomys whiteheadi, Lariscus insignis and Sundasciurus tenuis. The following parasites, Capillaria hepatica, Hymenolepis sp., Raillietina sp. and Taenia taeniaformis are considered of medical importance.
  12. Kramer I, Hooning MJ, Mavaddat N, Hauptmann M, Keeman R, Steyerberg EW, et al.
    Am J Hum Genet, 2020 11 05;107(5):837-848.
    PMID: 33022221 DOI: 10.1016/j.ajhg.2020.09.001
    Previous research has shown that polygenic risk scores (PRSs) can be used to stratify women according to their risk of developing primary invasive breast cancer. This study aimed to evaluate the association between a recently validated PRS of 313 germline variants (PRS313) and contralateral breast cancer (CBC) risk. We included 56,068 women of European ancestry diagnosed with first invasive breast cancer from 1990 onward with follow-up from the Breast Cancer Association Consortium. Metachronous CBC risk (N = 1,027) according to the distribution of PRS313 was quantified using Cox regression analyses. We assessed PRS313 interaction with age at first diagnosis, family history, morphology, ER status, PR status, and HER2 status, and (neo)adjuvant therapy. In studies of Asian women, with limited follow-up, CBC risk associated with PRS313 was assessed using logistic regression for 340 women with CBC compared with 12,133 women with unilateral breast cancer. Higher PRS313 was associated with increased CBC risk: hazard ratio per standard deviation (SD) = 1.25 (95%CI = 1.18-1.33) for Europeans, and an OR per SD = 1.15 (95%CI = 1.02-1.29) for Asians. The absolute lifetime risks of CBC, accounting for death as competing risk, were 12.4% for European women at the 10th percentile and 20.5% at the 90th percentile of PRS313. We found no evidence of confounding by or interaction with individual characteristics, characteristics of the primary tumor, or treatment. The C-index for the PRS313 alone was 0.563 (95%CI = 0.547-0.586). In conclusion, PRS313 is an independent factor associated with CBC risk and can be incorporated into CBC risk prediction models to help improve stratification and optimize surveillance and treatment strategies.
  13. John J, Nandhini AR, Velayudhaperumal Chellam P, Sillanpää M
    Environ Chem Lett, 2021 Oct 07.
    PMID: 34642583 DOI: 10.1007/s10311-021-01326-4
    Microplastic pollution has recently been identified as a major issue for the health of ecosystems. Microplastics have typically sizes of less than 5 mm and occur in various forms, such as pellets, fibres, fragments, films, and granules. Mangroves and coral reefs are sensitive and restricted ecosystems that provide free ecological services such as coastal protection, maintaining natural cycles, hotspots of biodiversity and economically valuable goods. However, urbanization and industrial activities have started contaminating even these preserved ecosystems. Here we review sources, occurrence, and toxicity of microplastics in the trophic levels of mangrove and coral reef ecosystems. We present detection methods, such as microscopic identification and spectroscopy. We discuss mitigating measures that prevent the entry of microplastics into the marine environment.
  14. Milne RL, Kuchenbaecker KB, Michailidou K, Beesley J, Kar S, Lindström S, et al.
    Nat Genet, 2017 Dec;49(12):1767-1778.
    PMID: 29058716 DOI: 10.1038/ng.3785
    Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414 with breast cancer), all of European origin. We identified independent associations at P < 5 × 10-8 with ten variants at nine new loci. At P < 0.05, we replicated associations with 10 of 11 variants previously reported in ER-negative disease or BRCA1 mutation carrier GWAS and observed consistent associations with ER-negative disease for 105 susceptibility variants identified by other studies. These 125 variants explain approximately 16% of the familial risk of this breast cancer subtype. There was high genetic correlation (0.72) between risk of ER-negative breast cancer and breast cancer risk for BRCA1 mutation carriers. These findings may lead to improved risk prediction and inform further fine-mapping and functional work to better understand the biological basis of ER-negative breast cancer.
  15. Lolekha S, Cooksley G, Chan V, Isahak I, Ismael S, John J, et al.
    PMID: 11414406
    Meningitis due to an invasive Haemophilus influenzae type b (Hib) infection, has been previously perceived to be relatively uncommon in Asia. However, the incidence of disease and its impact may have been underestimated. In addition to a lack of microbiological facilities in some hospitals, difficulties in culturing the organism and the widespread use of antibiotics may have hidden the true incidence of the disease in some countries. Furthermore, the reported disease burden probably underestimates the incidence of Hib pneumonia. The epidemiology of invasive Hib disease for various Asian nations is reviewed in this paper. Hospital-based studies show that Hib is a major cause of bacterial meningitis and/or pneumonia in the Philippines, India, Thailand, Malaysia, Indonesia and Vietnam. Singapore and Hong Kong have a low incidence of infection compared with Western and other Asian nations. This low incidence is not due to a higher level of natural protective antibodies, but may be related to an interaction between environmental and genetic factors. Therefore the widespread belief that Hib infection is unimportant in Asia does not refer to Asia as a whole and possibly to Chinese patients only, and failure to recognize this has serious implications. The inclusion of Hib vaccine in the routine infant immunization schedule in many industrialized nations has significantly reduced the incidence of invasive disease. Recent studies have shown Hib vaccination is also effective in preventing invasive disease in children in developing countries. While population-based data may be required to confirm the need for public-funded infant Hib immunization in Asia, its introduction in countries with a high incidence of Hib meningitis and/or pneumonia has the potential to significantly improve pediatric health and survival.
  16. Md Bohari NF, Kruger E, John J, Tennant M
    Int Dent J, 2019 Jun;69(3):223-229.
    PMID: 30565655 DOI: 10.1111/idj.12454
    OBJECTIVE: The aim of this study was to analyse, in detail, the distribution of primary dental clinics in relation to the Malaysian population and relative population wealth, to test the hypothesis that an uneven distribution of dental services exists in Malaysia.

    METHOD: This 2016 study located every dental practice in Malaysia (private and public) and mapped these practices against population, using Geographic Information Systems (GIS) tools. Population clusters within 5, 10 and 20 km of a dental clinic were identified, and clinic-to-population ratios were ascertained. Population data were obtained from the Population and Housing Census of Malaysia 2010. Population relative wealth was obtained from the 2014 Report on Household Income and Basic Amenities Survey for Malaysia. The physical address for each dental practice in Malaysia was gathered from the Official Portal of Ministry of Health Malaysia. All data for analysis were extracted from the integrated database in Quantum GIS (QGIS) into Microsoft Excel.

    RESULT: The population of Malaysia (24.9 million) was distributed across 127 districts, with 119 (94%) having at least one dental clinic. Sixty-four districts had fewer than 10 dental clinics, and 11.3% of Malaysians did not reside in the catchment of 20 km from any dental clinic. The total dental clinic-to-population ratio was 1:9,000: for public dental clinics it was 1:38,000 and for private clinics it was 1:13,000.

    CONCLUSION: Dental services were distributed relative to high population density, were unevenly distributed across Malaysia and the majority of people with the highest inaccessibility to a dental service resided in Malaysian Borneo.

  17. Loo JSE, Lim SW, Ng YK, Tiong JJL
    Int J Pharm Pract, 2017 Dec;25(6):429-437.
    PMID: 28211115 DOI: 10.1111/ijpp.12352
    OBJECTIVES: To identify factors influencing the decisions of Malaysian first-year pharmacy undergraduate students in private higher education when choosing to pursue a degree in pharmacy as well as their choice of private university.

    METHODS: This cross-sectional study employed a validated, self-administered questionnaire which was administered to 543 first-year pharmacy students from nine different private universities. Factor analysis was utilised to extract key factors from the responses. Descriptive and inferential statistics were used to analyse the data.

    KEY FINDINGS: Eight factors motivating students' decision to study pharmacy emerged from the responses, accounting for 63.8% of the variance observed. Students were primarily motivated by intrinsic interests, with work conditions and profession attributes also exerting significant influence. In terms of choice of private university, nine factors were identified, accounting for 73.8% of the variance observed. The image of the school and university were most influential factors in this context, followed by university safety, programme attributes and financial factors.

    CONCLUSIONS: First-year pharmacy students in the private higher education sector are motivated by intrinsic interest when choosing to study pharmacy over other courses, while their choice of private university is influenced primarily by the image of the school and university.

  18. Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.
    Autophagy, 2021 Jan;17(1):1-382.
    PMID: 33634751 DOI: 10.1080/15548627.2020.1797280
    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
  19. Nambiar P, John J, Al-Amery SM, Purmal K, Chai WL, Ngeow WC, et al.
    ScientificWorldJournal, 2013;2013:213757.
    PMID: 24348143 DOI: 10.1155/2013/213757
    Orangutans are believed to have close biological affinities to humans. Teeth being the hardest tissue provide useful information on primate evolution. Furthermore, knowledge of the pulp chamber and root canal morphology is important for dental treatment. A female Bornean orangutan and a Sumatran male orangutan skull were available for this study. Both of their dentitions, comprising 50 teeth, were scanned employing the cone-beam computed tomography for both metrical and nonmetrical analyses. Measurements included tooth and crown length, root length, enamel covered crown height, root canal length (posterior teeth), length of pulpal space (anterior teeth), and root canal width. Nonmetrical parameters included number of canals per root, number of foramina in each root, and root canal morphology according to Vertucci's classification. It was found that the enamel covered crown height was the longest in the upper central incisors although the canine was the longest amongst the anterior teeth. Both the upper premolars were three-rooted while the lower second premolar of the Sumatran orangutan was two-rooted, with two foramina. The mandibular lateral incisors of the Bornean orangutan were longer than the central incisors, a feature similar to humans. In addition, secondary dentine deposition was noticed, a feature consistent with aged humans.
  20. Al-Amery SM, Nambiar P, John J, Purmal K, Ngeow WC, Mohamed NH, et al.
    J Vet Dent, 2018 Jun;35(2):96-102.
    PMID: 29865987 DOI: 10.1177/0898756418776448
    This case report illustrates the teeth morphology of a chimpanzee and its anatomical variations. A well-preserved skull of a male Pan troglodytes troglodyte chimpanzee was scanned using a cone-beam computed tomography machine. Measurements included tooth and crown height, root length, root canal length and width (posterior teeth), and pulp cavity length (anterior teeth). Nonmetrical parameters included number of canals and foramina per root of every root. Interestingly, the mandibular central incisor was longer than the lateral incisor, and all the mandibular anterior teeth presented with a solitary flame-shaped or conical-calcified structure in their pulp cavity. The premolars are usually dual rooted except for the first maxillary premolar that displayed 3 roots. Other unusual discoveries were the presence of bilateral radicular dens invaginatus in the mandibular first premolars and the possibility of having 2 canals and 2 foramina in the roots of the posterior teeth. The presence of conical stone mineralizations at the pulp cavity and the presence of dens invaginatus were of particular interest.
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