Sociodemographic factors have received considerable attention in the literature with regards its relationship with caries. However, the related information among children ages 12-17 is fairly limited. Birth order has been consistently found to be associated with diseases hypothesized to have an infectious aetiology but only few studies have examined its relationship with dental caries. The aims of this study were to determine the association of birth order and the sociodemographic background of subjects with caries and high caries experience among 16-year-old schoolchildren in Tumpat district, Kelantan. This was a case-control study. A total of 1087 16-year-old schoolchildren were examined intraorally for their caries status. They were categorized into three groups namely caries free (DMFS=0) mild caries (DMFS= 1-7) and high caries (DMFS ≥8) group based on DMFS score. Cases were the caries group and the controls were the caries free group. In each group, 163 subjects were selected by using simple random sampling. A questionnaire was used to obtain personal information of the subjects, birthweight and sociodemographic background. Analysis involved was ordinal logistic regression. The factor that was found to have association with caries and high caries experience determined using multiple ordinal logistic regression analysis was educational level of parents (OR=1.55, 95% CI: 1.06; 2.28). This study showed that birth order was not a significant factor associated with caries experience. Among the sociodemographic factors, only parent’s educational level was found to be associated with caries and high caries experience.
The purpose of this study was to determine the dimensional accuracy of the skull models produced by Rapid prototyping technology using stereolithography apparatus. Computed tomography images were captured from four dry normal adult human skulls. The resultant 2-D images were stored in Digital Imaging and Communications in Medicine (DICOM) format. The segmentation of the images was prepared in MIMICS software. The slice files were then exported to a stereolithography apparatus (SLA) to produce the replica of each skull. Eight linear measurements were repeatedly made between identified landmarks on each of the original skull and its replica model using an electronic digital calliper. Each of the linear measurements was repeated 5 times and the average was taken to determine the absolute difference and percent difference between the original skull and its replica model. The overall absolute difference between the four human adult skulls and its replica models was 0.23 mm with a standard deviation of 1.37 mm. The percent difference was 0.08% with a standard deviation of 1.25%. The degree of error established by this system seems affordable in clinical applications when these models are used in the field of dental surgery for surgical treatment planning.
The aim of this study was to determine the age and sequence of eruption of permanent teeth, as well as gender differences, in children and adolescents in Kelantan, Malaysia. Cross-sectional data on permanent teeth 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 registers. There were 2,382 subjects in the sample, 1,062 boys and 1,320 girls. The data were subjected to probit regression analysis. The mean age of eruption of lower first molar was 6.0 (95%CI: 5.8, 6.2) years. The median age of eruption of each tooth was earlier in girls than in boys. Although the range of years during which the permanent teeth erupted was similar in both sexes, i.e. 6-12 years, the sequence of the tooth eruption 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.
Radiotherapy is an important treatment modality for head and neck tumours. One of its major drawbacks is post-treatment salivary gland hypofunction. This study was performed to objectively evaluate the salivary gland function in post-irradiated head and neck tumour patients.
The aim of this study was to determine the prevalence and association of speech disorders among operated cleft lip and palate children (CLP) in Northeast Malaysia. A comparative cross sectional study was performed on 98 operated CLP and 109 non-cleft subjects that aged between 3- 12-years-old. Data collection was done clinically and also by recording speech samples of each subject from both groups using a portable cassette recorder. Results showed that the prevalence of speech abnormality was 61.2% (95% CI: 51.41-71.04) and the risk of having speech abnormality was 174.5 times (95% CI: 23.04, 1320.67; P value < 0.001) in CLP children compared to non-cleft children. Therefore it was found that children with appropriately repaired CLP in Northeast Malaysia failed to have normal speech.
The aim of this study was to evaluate the morphological and biological properties of a locally produced "Bovine Bone Sponge" for use in dentistry. Bovine bone sponge was prepared from local calf bone. Endotoxin level and surface properties were investigated. The pore size and water uptake ability were measured and results were compared with the commercial haemostatic agent. The material was tested for its haemostatic property and its inhibition of alveolar bone resorption in a sheep model following dental extraction. Results revealed a significant difference in haemostatic effect, and a shorter bleeding time and a lower rate of alveolar bone resorption in bovine bone sponge compare to a commercial haemostatic agent.
The aim of this study was to evaluate the mechanical properties and glass transition temperature (Tg) of a denture base material prepared from high molecular weight poly methyl methacrylate (PMMA) and alumina (Al2O3). The glass transition temperature was studied by using differential scanning calorimetry (DSC). The effect of powder-to-liquid ratio was investigated. The result showed that the tensile properties and the Tg were slightly effected by the powder-to-liquid ratio. The ratio of 2.2:1 by weight of powder to liquid was found to be the best ratio for mixing the material to give the best result in this formulation.
The aim of this study was to evaluate the tensile properties and water absorption of denture base material prepared from high molecular weight poly methyl methacrylate (PMMA) and alumina (Al2O3) as particulate filler. Specimens for mechanical testing were prepared by adding composite powder to the monomer followed by hand mixing as in dental laboratory procedure. The tensile strength of the prepared denture base material was slightly higher than commercial denture base material, while the water absorption was almost the same for all formulation of denture base materials.
There was a significant increased in Absolute Contact Length measurements of endosteal bone growth along the Nickel-Titanium (NiTi) implant coated with the natural coral powder and Hydroxyapatite (HA) compared to the non-calcium coated implants. This study demonstrated that coated implants seemed to show earlier and higher osseointergration phenomena compared to non coated ones. Furthermore, there was significantly greater bone-to-implant contact at the apical 1/3rd of the coated implants.
The aim of this study was to evaluate the effect of powder-to-liquid ratio on the glass transition temperature (Tg) and the tensile properties of denture base material prepared from poly (methyl methacrylate) (PMMA) and hydroxyapatite (HA) previously treated with 3-trimethoxysilylpropyl methacrylate (gamma-MPS). Specimens for mechanical testing were prepared by adding composites powder (PMMA, BPO and HA) to the monomer (MMA and EGDMA) followed by hand mixing as in dental laboratory description usage. The glass transition temperature was studied by using differential scanning calorimetry (DSC). It was observed that the tensile properties and the Tg were affected by the powder-to-liquid ratio. The mechanical characterization of the materials were performed by using single edge notch-tension (SEN-T) specimens; the fracture toughness was slightly higher in formulation which contained HA filler compared to commercial denture base material.