Effective pulp capping material must be biocompatible and have the ability to induce dentin bridge formation as well as having suitable physical and mechanical properties; however, many current materials do not satisfy the clinical requirements. This study aimed to assess the physical and mechanical properties of gypsum-based chitosan material (Gp-CT) and to evaluate its effects on cellular properties of stem cells from human exfoliated deciduous teeth (SHED). The experimental material was prepared with different concentrations of chitosan (CT) with or without BMP-2. Then, setting time, compressive strength, and pH were determined. In addition, cell viability, alkaline phosphatase (ALP) activity, and cell attachment were assessed. The setting time, compressive strength, and pH obtained were 4.1-6.6 min, 2.63-5.83 MPa, and 6.5-5.7, respectively. The cell viability to gypsum (Gp) with different CT concentrations was similar to that of the control on day 1 but statistically different from that of Gp alone on day 3. The ALP activity of SHED was significantly higher (p < 0.05) in CT- and BMP-2-containing materials than those in the control and Dycal at days 3 and 14. The scanning electron microscopy (SEM) image revealed that flattened cells were distributed across and adhered to the material surface. In conclusion, Gp-CT material shows promise as a potential material for direct pulp capping.
Background: Periodontitis is a public health concern since it is a major factor in tooth loss worldwide and has association with many systemic diseases. Sleep is a complex and essentially biological process and a critical factor for maintaining mental and physical health. Since inflammation is characteristic of both chronic periodontitis and sleep deprivation, few studies in recent years present the contradictory results regarding this potential association. The objective of the present study was to investigate the association between quality of sleep and chronic periodontitis.
Materials and Methods: A total of 200 individuals participated in this study. All participants underwent a comprehensive clinical periodontal examination. Case-control were identified using the Centers for Disease Control and Prevention/American Academy of Periodontology case definitions for periodontal disease. The quality of sleep was assessed by Pittsburgh Sleep Quality Index. The univariate and multivariate logistic regression analysis was used to test the influence of variables (quality of sleep, age, sex, ethnicity, education, and socioeconomic status), in the occurrence of periodontitis. Odds ratio (OR) and respective confidence intervals (CIs) were calculated and reported. P =0.05 was considered statistically significant.
Results: The prevalence of poor quality of sleep was 56.75% in cases (periodontitis group) and 43.24% in control group. There was positive association between quality of sleep and chronic periodontitis (OR = 3.04; 95% CI = 1.42-6.5; P = 0.004). In multivariate logistic regression analysis, only the age was significantly related to the periodontitis (OR = 1.11; 95% CI = 1.07-1.41; P < 0.001), other variables failed to reach the significant level.
Conclusion: Poor quality of sleep was significantly associated with chronic periodontitis. Only the age was significantly related to periodontitis among the other covariable measured.
The post-natal dental pulp tissue contains a population of multipotent mesenchymal progenitor cells known as dental pulp stromal/stem cells (DPSCs), with high proliferative potential for self-renewal. In this investigation, we explored the potential of DPSCs to differentiate into pancreatic cell lineage resembling islet-like cell aggregates (ICAs). We isolated, propagated, and characterized DPSCs and demonstrated that these could be differentiated into adipogenic, chondrogenic, and osteogenic lineage upon exposure to an appropriate cocktail of differentiating agents. Using a three-step protocol reported previously by our group, we succeeded in obtaining ICAs from DPSCs. The identity of ICAs was confirmed as islets by dithiozone-positive staining, as well as by expression of C-peptide, Pdx-1, Pax4, Pax6, Ngn3, and Isl-1. There were several-fold up-regulations of these transcription factors proportional to days of differentiation as compared with undifferentiated DPSCs. Day 10 ICAs released insulin and C-peptide in a glucose-dependent manner, exhibiting in vitro functionality. Our results demonstrated for the first time that DPSCs could be differentiated into pancreatic cell lineage and offer an unconventional and non-controversial source of human tissue that could be used for autologous stem cell therapy in diabetes.
Multipotent stem cells derived from human exfoliated deciduous teeth (SHED) represent a promising cell source for tissue regeneration. In the present study we decided to test the inductive effect of chitosan and transforming growth factor-β1 (TGFβ1) as a scaffold/factor combination on SHED proliferation and osteogenic differentiation.
To investigate the role of geography (place of residence) as a moderator in the relationship between dental caries disease and treatment experience and dental fear in 16-year-olds living in Malaysia.
Hertwig's epithelial root sheath (HERS) cells play a pivotal role during root formation of the tooth and are able to form cementum-like tissue. The aim of the present study was to establish a HERS cell line for molecular and biochemical studies using a selective digestion method. Selective digestion was performed by the application of trypsin-EDTA for 2 min, which led to the detachment of fibroblast-like-cells, with the rounded cells attached to the culture plate. The HERS cells displayed a typical cuboidal/squamous-shaped appearance. Characterization of the HERS cells using immunofluorescence staining and flow cytometry analysis showed that these cells expressed pan-cytokeratin, E-cadherin, and p63 as epithelial markers. Moreover, RT-PCR confirmed that these cells expressed epithelial-related genes, such as cytokeratin 14, E-cadherin, and ΔNp63. Additionally, HERS cells showed low expression of CD44 and CD105 with absence of CD34 and amelogenin expressions. In conclusion, HERS cells have been successfully isolated using a selective digestion method, thus enabling future studies on the roles of these cells in the formation of cementum-like tissue in vitro.
We investigated the relationship of the maxillary central incisors to the incisive papilla in wearers of complete dentures. First, image analyzer software was used to examine the relationship of the midpoint of the incisive papilla to the labial surface of the maxillary central incisors on occlusal photographs of 120 maxillary casts from dentate Malaysian adults. Then, an Alma denture gauge was used to identify the position of the labial surface of the maxillary central incisors in relation to the midpoint of the incisive papilla in complete dentures from 51 patients who requested replacement dentures at the Faculty of Dentistry, University of Malaya. The mean incisor distance to the incisive papilla in dentate adults was 9.59 ± 1.00 mm, while the mean incisor distance to the incisive papilla in complete dentures was 6.34 ± 1.87 mm. Thus, in our sample of edentulous patients, the anterior teeth in complete dentures were positioned approximately 3 mm closer to the incisive papilla, as compared with the position of the central incisors in natural dentition, and did not duplicate the position of the natural anterior teeth.
Maxillofacial injuries are among the commonest forms of body injuries. There are three divisions, namely, facial bone fractures, soft tissue injuries, and dentoalveolar injuries. Etiologies include motor vehicle accidents, assaults, falls, and sporting injuries. The aim of this study was to determine the profiles including the causes of maxillofacial injuries seen in an urban government hospital in the mainland of Penang State, Malaysia.
Thalassaemia is a public health problem in Malaysia. It is known to cause skeletal deformity. The purpose of this study was to compare the skeletal, dentoalveolar, and soft tissue features of Malay transfusion-dependent thalassaemia (TDT) patients with a Malay control group. Lateral cephalometric radiographs of 30 Malay (14 males and 16 females aged 6.4-21.8 years) TDT patients and 60 normal Malays matched for chronological age and gender were analysed and compared using an independent t-test. The TDT group showed a similar sagittal relationship to the control group but with a significantly increased (P < 0.01) mandibular plane inclination. They also showed a significantly shorter (P ≤ 0.001) mandibular body, ramus length, and posterior face height and consequently a smaller ratio of posterior to anterior face height (P < 0.01). The upper and lower lips were significantly procumbent (P < 0.001) in the TDT group together with a significantly smaller nasolabial angle (P < 0.05). Dentoalveolar measurements showed less proclined maxillary teeth in the TDT group compared with the controls (P < 0.05). The cephalometric features of Malay TDT patients were characterized by a mild Class II skeletal pattern, prominent vertical growth direction of the mandible, and protruded upper and lower lips.
To determine the prevalence, distribution, severity and treatment need of enamel opacities among 11-12 year-old school children in a fluoridated urban community.
Motorcycle casualties represent significant number in road traffic accidents in Malaysia, and among all the injuries, facial injuries pose many significant problems physiologically, functionally, and aesthetically. The aim of this study was to analyze the pattern of maxillofacial as well as other injuries in motorcyclists who were seen at Hospital Universiti Kebangsaan Malaysia.Patients' records from January 2004 to December 2005 were reviewed. Data related to demographics, vehicle/object involved in collision, involvement as a rider or pillion, whether a helmet was worn or not, location of injuries on the face/facial bones, and other associated injuries were collected.A total of 113 cases of motorcycle accidents were recorded; 106 males and 7 females were involved. Mean age was 25.8 years. Among all the races, Malay had the highest involvement (72.3%), followed by Chinese (14.3%), Indians (8.9%), and others (5.4%). The types of collision were either a single-vehicle collision (i.e., skidded) or with another vehicle/s or object (e.g., tree, stone, or lamppost). The injuries were mainly seen on the lower face (46.9%) followed by midface (25.7%) and a combination of the midface and lower face (15%) and others (12.4%). The most frequent other associated injuries recorded were orthopedic and head injuries.
The present study was conducted to compare the cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper).
BACKGROUND: To evaluate the psychometric properties of the faces version of the Modified Child Dental Anxiety Scale (MCDASf) Malay version in 5-6 and 9-12 year-old children.
METHODS: The MCDASf was cross culturally adapted from English into Malay. The Malay version was tested for reliability and validity in 3 studies. In the Study 1, to determine test-retest reliability of MCDASf scale, 166 preschool children aged 5-6 years were asked to rank orders five cartoons faces depicting emotions from 'very happy' to 'very sad' faces on two separate occasions 3 weeks apart. A total of 87 other 5-6 year-old children completed the Malay-MCDASf on two separate occasions 3 weeks apart to determine test-retest reliability for Study 2. In study 3, 239 schoolchildren aged 9-12 years completed the Malay-MCDASf and the Malay-Dental Subscale of the Children Fear Survey Schedule (CFSS-DS) at the same sitting to determine the criterion and construct validity.
RESULTS: In study 1, Kendall W test showed a high degree of concordance in ranking the cartoon faces picture cards on each of the 2 occasions (time 1, W = 0.955 and time 2, W = 0.954). The Malay-MCDASf demonstrated moderate test-retest reliability (Intraclass correlation coefficient = 0.63, p <0.001) and acceptable internal consistency for all the 6 items (Cronbach's alpha = 0.77) and 8 items (Cronbach's alpha = 0.73). The highest MCDASf scores were observed for the items 'injection in the gum' and 'tooth taken out' for both age groups. The MCDASf significantly correlated with the CFSS-DS (Pearson r = 0.67, p < 0.001).
CONCLUSIONS: These psychometric findings support for the inclusion of a cartoon faces rating scale to assess child dental anxiety and the Malay-MCDASf is a reliable and valid measure of dental anxiety in 5-12 year-old children.
The aim of this retrospective study is to report on the prevalence of post-extraction complications among patients attending the Oral Surgery outpatient clinic of the Faculty of Dentistry, University of Malaya over a 12-month period from January to December, 1992. The prevalence of post-extraction complications which required further treatment was only 3.4% (n = 100), out of a total of 2968 patients who had extraction of one or more permanent teeth. Analysis based on complete clinical reports (n = 79) showed that dry socket accounted for nine out of ten cases of post-extraction complications. However the aetiology was largely unknown. No obvious association with medical history could be made. Lower teeth were more likely to have complications. The most common teeth associated with dry socket were the molars (76%) and premolars (19%). The most common molars to be affected are the first, followed by the third and lastly the second molars. A brief review of current aetiological factors of dry socket was discussed.
The odontogenic keratocyst has been well documented and extensively studied. It is of particular interest because of its high recurrence rate and aggressive nature. The material for this study consisted of 70 cases of odontogenic keratocysts in predominantly ethnic Chinese patients who were treated from 1981 to 1996. The cases were retrospectively studied to compare characteristics of the lesion in this population with those in previous reports. Most of the patients in this series were 21 to 30 years of age. Association with an impacted mandibular third molar was found in more than 50% of the cases. The recurrence rate was 20% for 35 patients with a follow-up period of at least 5 years. The follow-up period for the whole series ranged from 1 to 16 years. Treatment was surgical enucleation with peripheral ostectomy. There were no significant differences in characteristics with respect to presentation and prognosis between this series and those described in previous publications.
One hundred and ninety-eight single-rooted teeth from individuals aged 21-90 yr of Caucasian, Malay, Chinese Malay and Indian Malay origin were studied. Single or serial longitudinal sections of extracted teeth were cut following dye imbibition of patent dentinal tubules. The extent of sclerosis of apical dentinal tubules was assessed and correlated with the age of the individual. Correlation with age was higher in the Caucasian than the Malay races and within the Malaysian racial groups correlation with age was highest in the Malays and lowest in the Chinese. It is concluded that factors other than age may be important in the formation of sclerotic apical dentine in teeth of different racial origin. The effect of racial origin should be considered when using sclerosis as a means of age determination in forensic cases.
The medicaments used in this study were buffered glutaraldehyde and formocresol. Schiff's reagent was used in the quantification of aldehyde released into the collecting medium. The results of this study clearly show that formocresol diffused throughout the dentine and cementum within fifteen minutes following a pulpotomy procedure, whereas no diffusion of buffered glutaraldehyde was observed.