Displaying all 17 publications

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  1. Curnoe D, Datan I, Zhao JX, Leh Moi Ung C, Aubert M, Sauffi MS, et al.
    PLoS One, 2018;13(6):e0196633.
    PMID: 29874227 DOI: 10.1371/journal.pone.0196633
    The skeletal remains of Late Pleistocene-early Holocene humans are exceptionally rare in island Southeast Asia. As a result, the identity and physical adaptations of the early inhabitants of the region are poorly known. One archaeological locality that has historically been important for understanding the peopling of island Southeast Asia is the Niah Caves in the northeast of Borneo. Here we present the results of direct Uranium-series dating and the first published descriptions of three partial human mandibles from the West Mouth of the Niah Caves recovered during excavations by the Harrissons in 1957. One of them (mandible E/B1 100") is somewhat younger than the 'Deep Skull' with a best dating estimate of c30-28 ka (at 2σ), while the other two mandibles (D/N5 42-48" and E/W 33 24-36") are dated to a minimum of c11.0-10.5 ka (at 2σ) and c10.0-9.0 ka (at 2σ). Jaw E/B1 100" is unusually small and robust compared with other Late Pleistocene mandibles suggesting that it may have been ontogenetically altered through masticatory strain under a model of phenotypic plasticity. Possible dietary causes could include the consumption of tough or dried meats or palm plants, behaviours which have been documented previously in the archaeological record of the Niah Caves. Our work suggests a long history back to before the LGM of economic strategies involving the exploitation of raw plant foods or perhaps dried and stored meat resources. This offers new insights into the economic strategies of Late Pleistocene-early Holocene hunter-gatherers living in, or adjacent to, tropical rainforests.
    Matched MeSH terms: Mandible/anatomy & histology*
  2. Ngeow WC, Chai WL
    Clin Anat, 2020 Nov;33(8):1214-1227.
    PMID: 31943382 DOI: 10.1002/ca.23567
    The mandibular canal is a conduit that allows the inferior alveolar neurovascular bundle to transverse the mandible to supply the dentition, jawbone and soft tissue around the gingiva and the lower lip. It is not a single canal but an anatomical structure with multiple branches and variations. The branches are termed accessory, bifid or trifid canals depending on their number and configuration. A bifid mandibular canal is an anatomical variation reported more commonly than the trifid variant. Because of these variations, it is of the utmost importance to determine the exact location of the mandibular canal and to identify any branches arising from it prior to performing surgery in the mandible. This article reviews the prevalence, classification and morphometric measurements of these accessory mandibular canals, emphasizing their clinical significance.
    Matched MeSH terms: Mandible/anatomy & histology*
  3. Neo J
    Anesth Prog, 1989 Nov-Dec;36(6):276-8.
    PMID: 2490061
    The position of the mental foramen of the local Malays and Indians in Singapore was determined from a series of orthopantomograms. The most frequent location does not conform to the position cited in many anatomy, surgery, and dental anesthesia texts as being below and between the apices of the lower premolars. This data has implications in the teaching and practice of dental anesthesia. In both these races, the median location is just below the second premolar.
    Matched MeSH terms: Mandible/anatomy & histology*
  4. Ngeow WC, Yuzawati Y
    J Oral Sci, 2003 Sep;45(3):171-5.
    PMID: 14650583
    Knowledge of the position of the mental foramen is important both when administering regional anesthesia and performing periapical surgery in the mental region of the mandible. This study determines the position of the mental foramen in a selected Malay population. One hundred and sixty nine panoramic radiographs of Malay patients retrieved from a minor oral surgery waiting list were selected to identify the normal range for the position of the mental foramen. The foramen was not included in the study if there was any mandibular tooth missing between the lower left and right first molars (36-46). The findings indicated the most common position for the mental foramen was in line with the longitudinal axis of the second premolar (69.2%) followed by a location between the first and second premolar (19.6%). The right and left foramina were bilaterally symmetrical in three of six recorded positions in 67.7% patients. The mental foramen was most often in line with the second premolar.
    Matched MeSH terms: Mandible/anatomy & histology*
  5. Sghaireen MG, Alam MK, Patil SR, Rahman SA, Alhabib S, Lynch CD, et al.
    J Int Med Res, 2020 Mar;48(3):300060520912138.
    PMID: 32228352 DOI: 10.1177/0300060520912138
    Matched MeSH terms: Mandible/anatomy & histology*
  6. Kojima Y, Fukuyama I, Kurita T, Hossman MYB, Nishikawa K
    Sci Rep, 2020 07 29;10(1):12670.
    PMID: 32728121 DOI: 10.1038/s41598-020-69436-7
    The jaws of vertebrates display a striking diversity in form and function, but they typically open and close like a trapdoor rather than sliding like a saw. Here, we report unique feeding behaviour in the blunt-headed snail-eating snake, Aplopeltura boa (family Pareidae), where the snake cuts off and circumvents the indigestible part (the operculum) of its prey in the mouth using long sliding excursions of one side of the mandible, while the upper jaws and the mandible on the other side maintain a stable grasp on the prey. This behaviour, which we call 'mandibular sawing', is made possible by extraordinarily independent movements of the jaw elements and is a surprising departure from usual feeding behaviour in vertebrates.
    Matched MeSH terms: Mandible/anatomy & histology*
  7. Alias A, Ibrahim A, Abu Bakar SN, Swarhib Shafie M, Das S, Abdullah N, et al.
    Clin Ter, 2018 11 6;169(5):e217-e223.
    PMID: 30393808 DOI: 10.7417/CT.2018.2082
    INTRODUCTION: The first step in the forensic identification is sex determination followed by age and stature estimation, as both are sex-dependent. The mandible is the largest, strongest and most durable bone in the face. Mandible is important for sex confirmation in absence of a complete pelvis and skull.

    AIM: The aim of the present study was to determine sex of human mandible from morphology, morphometric measurements as well as discriminant function analysis from the CT scan.

    MATERIALS AND METHODS: The present retrospective study comprised 79 subjects (48 males, 31 females), with age group between 18 and 74 years, and were obtained from the post mortem computed tomography data in the Hospital Kuala Lumpur. The parameters were divided into three morphologic and nine morphometric parameters, which were measured by using Osirix MD Software 3D Volume Rendering.

    RESULTS: The Chi-square test showed that men were significantly association with square-shaped chin (92%), prominent muscle marking (85%) and everted gonial glare, whereas women had pointed chin (84%), less prominent muscle marking (90%) and inverted gonial glare (80%). All parameter measurements showed significantly greater values in males than in females by independent t-test (p< 0.01). By discriminant analysis, the classification accuracy was 78.5%, the sensitivity was 79.2% and the specificity was 77.4%. The discriminant function equation was formulated based on bigonial breath and condylar height, which were the best predictors.

    CONCLUSION: In conclusion, the mandible could be distinguished according to the sex. The results of the study can be used for identification of damaged and/or unknown mandible in the Malaysian population.

    Matched MeSH terms: Mandible/anatomy & histology*
  8. Zabidin N, Mohamed AM, Zaharim A, Marizan Nor M, Rosli TI
    Int Orthod, 2018 03;16(1):133-143.
    PMID: 29478934 DOI: 10.1016/j.ortho.2018.01.009
    OBJECTIVES: To evaluate the relationship between human evaluation of the dental-arch form, to complete a mathematical analysis via two different methods in quantifying the arch form, and to establish agreement with the fourth-order polynomial equation.

    MATERIALS AND METHODS: This study included 64 sets of digitised maxilla and mandible dental casts obtained from a sample of dental arch with normal occlusion. For human evaluation, a convenient sample of orthodontic practitioners ranked the photo images of dental cast from the most tapered to the less tapered (square). In the mathematical analysis, dental arches were interpolated using the fourth-order polynomial equation with millimetric acetate paper and AutoCAD software. Finally, the relations between human evaluation and mathematical objective analyses were evaluated.

    RESULTS: Human evaluations were found to be generally in agreement, but only at the extremes of tapered and square arch forms; this indicated general human error and observer bias. The two methods used to plot the arch form were comparable.

    CONCLUSION: The use of fourth-order polynomial equation may be facilitative in obtaining a smooth curve, which can produce a template for individual arch that represents all potential tooth positions for the dental arch.

    Matched MeSH terms: Mandible/anatomy & histology
  9. Wong SK, Patil PG
    J Prosthet Dent, 2018 Aug;120(2):210-213.
    PMID: 29551376 DOI: 10.1016/j.prosdent.2017.10.019
    STATEMENT OF PROBLEM: The inferior alveolar nerve (IAN) frequently loops backward before exiting from the mental foramen and spreads several millimeters medially to the foramen. Implant placement in this area may damage the nerve if the anterior loop area is not carefully identified in a radiographic or computed tomography (CT) evaluation.

    PURPOSE: The purpose of this observational study was to measure the prevalence of the presence of the anterior loop and to estimate sex and ethnicity-related variations in anterior loop length in the Malaysian population.

    MATERIAL AND METHODS: A total of 100 cone beam computed tomography (CBCT) Digital Imaging and Communications in Medicine (DICOM) files were selected from a pool of 810 ongoing or completed patients in 3 different ethnic groups: Malay (33), Indian (33), and Chinese (34). The DICOM data were imported into commercial software. The IAN was traced with software along with the anterior loop and part of the incisive nerve. The vertical length of the nerve was estimated from the canal to the opening of the mental foramen from the cross-sectional view and translated to the panoramic view. Measurement was made from this point to the most anterior point of the anterior loop by following the trajectory of the nerve and was repeated on the opposite side. A 2-way mixed analysis of variance (ANOVA) test was carried out to evaluate the sex- and ethnicity-related variations (α=.05).

    RESULTS: The anterior loop was present in 94% of the 100 participants. Overall anterior loop length (AnLL) ranged between 0.73 and 7.99 mm with a mean length of 3.69 ±1.75 mm on the left side and 3.85 ±1.73 mm on the right side. Among all participants, no statistically significant differences were found between the left and right sides of the mandible (P=.379). Overall, no significant main effect of ethnicity (P=.869) or sex (P=.576) was found on AnLL measurements. Also, with multiple comparisons, no significant effect was found between each pair of ethnic groups. Men in all 3 ethnic groups had greater AnLL than women.

    CONCLUSIONS: The anterior loop was present in 94% of the 100 participants among the 3 major ethnic groups of Malaysia. Overall AnLL ranged between 0.73 and 7.99 mm and mean lengths of 3.69 ±1.75 mm on the left side and 3.85 ±1.73 mm on the right side, with no significant ethnicity- or sex-related variations.

    Matched MeSH terms: Mandible/anatomy & histology*
  10. Wahid I, Sunahara T, Mogi M
    J Med Entomol, 2003 Mar;40(2):150-8.
    PMID: 12693842
    Maxillae and mandibles of males of 44 species of 12 mosquito genera and females of three autogenous genera and two partially autogenous species were examined under light microscopy and scanning electron microscopy. The maxillae and mandibles of male mosquitoes are delicate, tape-like structures with lengths characterizing genera or higher level classification units. Five patterns are recognized: (A) long maxillae and mandibles with mandibles longer than maxillae in Anopheles; (B) long maxillae and mandibles with maxillae longer than mandibles in Toxorhynchites; (C) short or intermediate lengths of maxillae with short mandibles in Aedes, Armigeres, Culex, Ochlerotatus, Orthopodomyia, and Uranotaenia; (D) short or intermediate length of maxillae with no mandibles in Mimomyia and Tripteroides; and (E) no maxillae and mandibles in Malaya and Topomyia. Maxillary and mandibular lengths of male mosquitoes show a positive correlation. Length of maxillae and mandibles of autogenous females are reduced to the same level as conspecific males. In contrast, females of partially autogenous species have complete maxillae and mandibles as in females of anautogenous species.
    Matched MeSH terms: Mandible/anatomy & histology
  11. Dung TM, Ngoc VTN, Hiep NH, Khoi TD, Xiem VV, Chu-Dinh T, et al.
    Sci Rep, 2019 02 28;9(1):3101.
    PMID: 30816230 DOI: 10.1038/s41598-019-39710-4
    This study aimed to define the width and length of the dental arch in 12-year-old Vietnamese children, and to elucidate differences between genders and among ethnic groups. A cross-sectional study was conducted in 4565 12 years-old children from the 4 major ethnic groups in Vietnam (Kinh, Muong, Thai, and Tay), with a healthy and full set of 28 permanent teeth that had never had any orthodontic treatment and with no reconstructive materials at the measured points. The mean variables in all subjects were 36.39 mm for upper inter-canine width; 46.88 mm for upper inter-first molar width; 59.43 mm for upper inter-second molar width; 10.41 mm for upper anterior length; 32.15 mm for upper posterior length 1; 45.52 mm for upper posterior length 2; 28.31 mm for lower inter-canine width; 41.63 mm for lower inter-first molar width; 54.57 mm for lower inter-second molar width (LM2W); 7.06 mm for lower anterior length (LAL); 26.87 mm for lower posterior length 1 (LP1L); and 41.29 mm for lower posterior length 2. Significant differences in these parameters between genders were found in all ethnic groups, except for LAL in the Kinh and Thai groups, and LP1L in the Tay group. Significant ethnic differences were also found in almost all parameters except LM2W in both males and females. Taken together, the representative sizes of dental arches of 12-year-old Vietnamese children have been defined. Our data indicate that there are some variations in dental arch dimensions among ethnic groups and between genders.
    Matched MeSH terms: Mandible/anatomy & histology
  12. Saidin S, Abdul Kadir MR, Sulaiman E, Abu Kasim NH
    J Dent, 2012 Jun;40(6):467-74.
    PMID: 22366313 DOI: 10.1016/j.jdent.2012.02.009
    The aim of this study was to analyse micromotion and stress distribution at the connections of implants and four types of abutments: internal hexagonal, internal octagonal, internal conical and trilobe.
    Matched MeSH terms: Mandible/anatomy & histology
  13. Purmal K, Alam MK, Moganadass DD, Zakariat NN, Cheong NW
    Aust Orthod J, 2013 May;29(1):34-42.
    PMID: 23785936
    To assess the applicability of Pont's Index in a Malaysian population by obtaining baseline measurements of dental arch shape based on premolar arch width, molar arch width and the combined width of the maxillary incisors. A secondary aim was to determine whether a correlation exists between arch widths, Pont's Index and the facial framework.
    Matched MeSH terms: Mandible/anatomy & histology
  14. Al-Khatib AR, Rajion ZA, Masudi SM, Hassan R, Anderson PJ, Townsend GC
    Orthod Craniofac Res, 2011 Nov;14(4):243-53.
    PMID: 22008304 DOI: 10.1111/j.1601-6343.2011.01529.x
    To investigate tooth size and dental arch dimensions in Malays using a stereophotogrammetric system.
    Matched MeSH terms: Mandible/anatomy & histology
  15. Voon YS, Patil PG
    J Prosthet Dent, 2018 Apr;119(4):568-573.
    PMID: 28838820 DOI: 10.1016/j.prosdent.2017.05.011
    STATEMENT OF PROBLEM: The genial tubercle is a clinically palpable landmark in the mandible and can be identified in cone beam computed tomography (CBCT). Its location can be used to measure the safe zone in the interforaminal region of the mandible. These measurements may be helpful for implant treatment planning in patients with complete edentulism.

    PURPOSE: The purpose of this clinical study was to evaluate the safe distance in the interforaminal region of the mandible measured from the genial tubercle level for implant osteotomy in a Chinese-Malaysian population.

    MATERIAL AND METHODS: A total of 201 Digital Imaging and Communications in Medicine (DICOM) files were selected for the study from the CBCTs of dentate or edentulous Chinese-Malaysian adult patients with ongoing or completed treatments. Measurements were made with implant planning software. The anatomy of the whole mandible was assessed in the coronal cross-sectional, horizontal view and in panoramic view. Measurements were obtained in millimeters on one side by locating and marking a genial tubercle and then marking the mesial margin of the mental foramen and the anterior loop of the inferior alveolar nerve. The corresponding points of these landmarks were identified on the crest of the mandibular ridge to measure the linear distances. All the measurement steps were repeated on the other side. The linear distance of 2 mm was deducted from the total distance between the genial tubercle and the anterior loop separately for left and right side measurements to identify the safe zone. The mixed 2-way analysis of variance (ANOVA) test was used to analyze side and sex-related variations.

    RESULTS: The mean safe zone measured at the crestal level from the genial tubercle site on the left side of the mandible was 21.12 mm and 21.67 mm on the right side. A statistically significant (P

    Matched MeSH terms: Mandible/anatomy & histology
  16. Kumar Potu B, Jagadeesan S, Bhat KM, Rao Sirasanagandla S
    Morphologie, 2013 Jun;97(317):31-7.
    PMID: 23806306 DOI: 10.1016/j.morpho.2013.04.004
    The retromolar foramen (RMF) and retromolar canal (RMC) are the anatomical structures of the mandible located in retromolar fossa behind the third molar tooth. This foramen and canal contain neurovascular structures which provide accessory/additional innervation to the mandibular molars and the buccal area. These neurovascular contents of the canal gain more importance in medical and dental practice, because these elements are vulnerable to damage during placement of osteointegrated implants, endodontic treatment and sagittal split osteotomy surgeries and a detailed knowledge of this anatomical variation would be vital in understanding failed inferior alveolar nerve blockage, spread of infection and also metastasis. Although few studies have been conducted in the past showing the incidence and types in different population groups, a lacunae in comprehensive review of this structure is lacking. Though this variation posed challenging situations for the practicing surgeons, it has been quite neglected and the incidence of it is not well presented in all the textbooks. Hence, we made an attempt to provide a consolidated review regarding variations and clinical applications of the RMF and RMC.
    Matched MeSH terms: Mandible/anatomy & histology*
  17. Wan Hassan WN, Stephenson PA, Waddington RJ, Sloan AJ
    J Dent, 2012 May;40(5):406-15.
    PMID: 22342686 DOI: 10.1016/j.jdent.2012.02.002
    Root resorption is a ubiquitous although undesirable sequela to orthodontic treatment. Current methods to investigate the pathophysiology have certain limitations. In pursuit to understand and develop treatment modalities for orthodontically induced root resorption, the ability to manipulate cells within their natural extracellular matrix in a three dimensional organotypic model is invaluable. The study aimed to develop a laboratory-based organotypic model to investigate the effect of orthodontic forces on the periodontium.
    Matched MeSH terms: Mandible/anatomy & histology
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