Age and sequence of eruption of permanent teeth in children and adolescents in North-eastern Malaysia

The aim of this study is to determine the age and sequence of eruption of permanent teeth as well as gender differences in children and adolescents in the state of Kelantan, north-eastern Malaysia. Cross-sectional data on permanent tooth eruption were collected by examining pre-school, primary and secondary school children of 5-17 years of age. The subjects were drawn by multistage random sampling from the school register. There were 2382 subjects in the sample, 1062 boys and 1320 girls. A tooth was considered erupted if any part of its crown was visible in the mouth. The data were subjected to probit analysis to compute the eruption time of each individual tooth in terms of median, 95th percentile and 99 percentile. The mean age of eruption of lower first molar is 6.0 years (5.8yr,6.2yr) at 95%CI and for lower canine is 10.2 years (10.0yr,l0.3yr) at 95%CI. The median age of eruption of each tooth was earlier in girls than in boys. Although the range of years during which the teeth erupted was similar in both sexes, the sequence of the individual teeth differed. All mandibular teeth, with the exception of first and second premolars in both males and females, tended to erupt earlier than their maxillary counterparts. The findings seem to correspond to earlier studies done in the other parts of the world, however the eruption time seems to be earlier compared to studies done in Thailand and Madras

Formation of Nanotubular TiOa Bioactive Oxide Layer on Titanium and Cell Response Studies by

This work focus on the formation of titanium oxide {Ti02) nanotubes on theTi-6AI-4V alloy by anodization method in organic ethylene giycoi electrolyte (EG). The dimension of nancAubes could betuned by changing the electrochemical parameters such as NH4F content, voltage applied; and anodization time. The average nanoporous or nonotube diameter and length were found to increase with increasing ambunt of fluoride, anodization voltage and anodization time. Minimum of 0.5 g NH4F is required for growth of nanotubes.:TT02 nanotubes with average diameter of 110 nm and 3.1 pm lengths were obtained in EG containing 0.7 g NH4F. Upon annealing from temperature 400°C to 600°C in argon atmosphere shows crystallization of the nanotubes to anatase phase exists at 400°C while rutile dominantly exists at eOO^C. Anodization in the organic electrolyte resulted in homogeneous structure unlike the one reported in aqueous acidified fluoride solution which resulted in inhomogeneous stnjcture due to the severe attack of the p-phase. For the case of behavior of cell interaction using human foreskin fibrobfast cells line (HS27) studies shown that amorphous Ti02 nanotubes structure has better cellular interaction as compare to anatase and rutile crystal structur

Effect of Vitamin E on Human Periodontal Ligament Fibroblasts

The periodontal ligament fibroblasts plays an essential role in the organization and maintenance of the connective tissue during development and in response to injuries and diseases. They are also responsible of the migration and differentiation of the variety of cells that takes part in the osteogenesis in response to external forces (1, 2). Age related changes include decreased fibroblasts density and cellular activity which slows orthodontic tooth movement due to prolonged response of the connective tissue to external forces which poses a potential risk in orthodontic treatment (3, 4). Vitamin E had been studied worldwide due to its health benefits in the fields of chronic diseases and ageing such as the anti-inflammatory and anti-osteoporotic effects (5, 6). Vitamin E consists of 2 major isoforms: tocopherols and tocotrienols, each with four distinct analogues (alpha, beta, gamma, and delta). Tocopherols are saturated forms of vitamin E, and tocotrienols are the unsaturated forms, distinguishable by the three double bonds in the tails of tocotrienols (7). Studies showed that tocotrienol is superior for its antioxidant properties as well as increasing cells viability and proliferation (8, 9). The current project aim to evaluate the response of human periodontal ligament fibroblasts (HPdLF) upon exposure to various concentrations of tocotrienols rich fraction (TRF) conditioned medium

Analysis of Tweed’s facial triangle in mixed dentition children with class III malocclusion treated by two different appliances

Reverse twin-block (RTB) and reverse pull face mask (RPFM) are two commonly used orthodontic appliances to treat Class III malocclusions in mixed dentition children

VR welding kit: welding training simulation in mobile virtual reality using multiple marker tracking method

Welding simulation design using virtual reality (VR) is a challenge, as numerous developments and research in the mechanical engineering fields are involved. One of the key challenges is the improvement of realism by considering a mixed system of real and virtual equipment. A conceptual design and research management framework is currently lacking which leveraging the combination of VR and marker tracking techniques. This study seeks to examine and evaluating the use of mobile VR in welding training and how multiple markers tracking methods can be incorporated to overcome the current problems in VR for welding training simulation. In this study, the VR Welding Kit application is created by utilizing the Vuforia tracking engine to provide an alternative interaction for mobile devices. The results of the experiment revealed a benchmark comparison with Oculus Quest, the high-end VR system, to investigate the efficiency of the proposed multiple marker interaction technique. Performance for both devices was recorded. The System Usability Scales (SUS) have also been used to obtain users' acceptance rates using these devices. The Simulator Sickness Questionnaire (SSQ) was used to assess the cybersickness of participants. The performance results show that mobile VR have a moderate gap completion time in seconds if compared to Oculus Quest. The SUS scored a satisfactory result which is 73.33. Besides, SSQ surveys result shows that most of the participant felt the simulation sickness was minimal

Root-crown ratios of permanent teeth in Malay patients attending HUSM Dental Clinic

Keywords Crown height, Permanent teeth, Root length, Root-crown ratio. Abstract The objectives of this study were to determine the normal mean value of the root-crown (R/C ratios) in Malay patients and their variations by gender and dental arch from orthopantomogram radiographs (OPGs). Two thousand nine hundred and twenty teeth with fully developed roots were measured from 112 OPGs. Subjects with history of maxillofacial trauma or orthodontic therapy were excluded. The mean age of the subjects was 19.1 (SD 2.08) years old for males while females 18.9 (SD 2.19) years old in the range from 15 to 22 years old. The intra-examiner reproducibility of the assessment method was good (Intraclass correlation coefficient 0.81). Results of this study showed that there was no significant difference between R/C ratios of males and females groups. However, the ratios of the antagonist teeth for both males and females were significantly greater in the mandible than in the maxilla (p<0.05 for right and left lateral incisors and right first premolars in male; p<0.001 for all other teeth). In both gender, the highest R/C ratio was mandibular second premolars and the lowest R/C ratio were maxillary central incisors. The rootcrown ratio could be used as a baseline data and reference to help in orthodontic diagnosis, treatment planning and prognosis as well as evaluation developmental root deficiency

A comparative study of cranafacial morphology in Malaysian aborigines and Malays

In clinical practice, cephalometric analysis is valuable in assessing facial and dentoskeletal relationships. It provides a measure of skeletal morphology and allows correlations of skeletal factors of malocclusion in and among populations. This study aims to provide cephalometric findings of a selected Orang Asli population ofKelantan particularly the Jahai tribe and compare values with other ethnic groups. It is a cross-sectional study involving 68 selected adults of the Jahai tribe. Cephalograms of adults aged 18-45 years were taken using a standard Orthopantomograph (OPT) machine. These cephalograms were individually traced by manual method using tracing paper and 2B pencil. The tracings of the cephalograms were then analyzed according to Steiner's analysis and SPSS Version 11.0. The analyses of each measurement characteristics of the sample were compared with the standard accepted values for other ethnic groups. It was found that the Jahai tribe of Orang Asli population in Kelantan has a more prominent bimaxillary protrusion compared with other ethnic groups. These findings confirmed that there were significant variations in the craniofacial features of Orang Asli population, particularly the Jahai tribe when compared with the other ethnic groups. These measurements served to complement existing incomplete data of craniofacial measurements in our local data bank. Thus, this tiny effort has a potential role in the completeness of craniofacial analyses of the local Orang Asli population. The information collated can further enhance valid comparisons and establish norms among tribes in Malaysia and in the Asia pacific regio

Comparison of Soft Tissue Changes Produced by Two Different Appliances on Mixed Dentition Children

Objective. This study was focused on comparing and analyzing the soft tissue changes induced by Reverse Twin-Block (RTB) and Reverse Pull Face Mask (RPFM) in early and late mixed dentition Malay children having Class III malocclusion. Methods. This cross-sectional study includes a total sample of 95 Malay children of both early (8-9 years) and late (10-11 years) mixed dentition stages. The comparison was between 49 samples treated by RTB and 46 samples treated by RPFM. Both pre- and posttreatment changes were assessed with Holdaway’s analysis using the CASSOS software. In each cephalogram, 71 anatomic landmarks were traced. Descriptive and multiple regression analyses were performed for statistical evaluation. Results. Statistically significant changes were noticed in soft tissue facial angle, subnasale to H-line, skeletal profile convexity, upper lip strain, H-line angle, lower lip to H-line, and inferior sulcus to H-line measurements. Gender disparity was noticed in upper lip strain. Other significant changes were influenced by the type of appliance. However, the mean differences were minute to notice clinically. Age difference did not have any effect on the treatment changes. Conclusions. RPFM revealed treatment outcome with more protruded upper lip than RTB