Population studies on the prevalence of temporomandibular disorders (TMD) and their associations with quality of life (QoL), emotional states and sleep quality in South-East Asian youths are not available. This cross-sectional study assessed the presence of TMD and their relationships to QoL, depression, anxiety, stress and sleep quality in a cohort of South-East Asian adolescents/young adults. Three hundred and sixty-two students from a polytechnic were enrolled in the study and completed an online questionnaire consisting of the Fonesca's Anamnestic Index (FAI), Oral Health Impact Profile for TMD (OHIP-TMD), Depression, Anxiety and Stress Scales-21 (DASS-21) and Pittsburgh Sleep Quality Index. The FAI appraises TMD severity while OHIP-TMD determines the effect of TMD on oral health-related QoL. Statistical analysis was performed using chi-square test for categorical data whilst one-way ANOVA/post hoc Bonferroni's tests were employed for numerical scores (P < 0.05). Of the 244 participants who completed the questionnaires in their entirety (37 males; 207 females, mean age 20.1 ± 3.2 years), 32.4% had mild TMD, 9.4% had moderate TMD and 58.2% were TMD free. The total prevalence of TMD was 41.8% (n = 102) and most OHIP-TMD domains including functional limitation (P = 0.000), physical pain (P = 0.000), handicapped (P = 0.000) and psychological discomfort (P = 0.001) showed significant differences in mean scores depending on TMD severity. A similar trend was observed for DASS-21. The majority of participants with TMD (69.6%; n = 71) had poor sleep quality (P = 0.004). TMD appear to be prevalent in South-East Asian youths with varying severity. Severity of TMD had some bearing on QoL, emotional states as well as sleep quality.

Objective To investigate the physical (setting time, hardness, flowability, microstructure) and chemical (pH change, calcium release, crystallinity) properties and the biological outcomes (cell survival and differentiation) of mineral trioxide aggregate (MTA) mixed using different proportions of propylene glycol (PG) and water.Material and Methods White MTA was mixed with different water/PG ratios (100/0, 80/20 and 50/50). Composition (XRD), microstructure (SEM), setting time (ASTM C266-13), flowability (ANSI/ADA 57-2000), Knoop hardness (100 g/10 s) and chemical characteristics (pH change and Ca2+ release for 7 days) were evaluated. Cell proliferation, osteo/odontoblastic gene expression and mineralization induced by MTA mixed with PG were evaluated. MTA discs (5 mm in diameter, 2 mm thick) were prepared and soaked in culture medium for 7 days. Next, the discs were removed and the medium used to culture dental pulp stem cells (DPSC) for 28 days. Cells survival was evaluated using MTS assay (24, 72 and 120 h) and differentiation with RT-PCR (ALP, OCN, Runx2, DSPP and MEPE) and alizarin red staining (7 and 14 days). Data were analysed using one-way ANOVA and Tukey’s post-hoc analysis (a=0.05).Results The addition of PG significantly increased setting time, flowability and Ca2+ release, but it compromised the hardness of the material. SEM showed that 50/50 group resulted porous material after setting due to the incomplete setting reaction, as shown by XRD analysis. The addition of PG (80/20 and 50/50) was not capable to improve cell proliferation or to enhance gene expression, and mineralized deposition of DPSC after 7 and 14 days as compared to the 100/0.Conclusion Except for flowability, the addition of PG did not promote further improvements on the chemical and physical properties evaluated, and it was not capable of enhancing the bioactivity of the MTA.

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Periodontitis involves complex interplay of bacteria and host immune response resulting in destruction of supporting tissues of the tooth. Toll-like receptors (TLRs) play a role in recognizing microbial pathogens and eliciting an innate immune response. Recently, the potential application of multipotent stem cells and pluripotent stem cells including human embryonic stem cells (hESCs) in periodontal regenerative therapy has been proposed. However, little is known about the impact of periodontopathogens on hESC-derived progenies. This study investigates the effects of heat-killed periodontopathogens, namely, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, on TLR and cytokine expression profile of hESC-derived progenies, namely, fibroblasts (hESC-Fib) and mesenchymal stem cells (hESC-MSCs). Additionally, the serotype-dependent effect of A. actinomycetemcomitans on hESC-derived progenies was explored. Both hESC-Fib and hESC-MSCs constitutively expressed TLR-2 and TLR-4. hESC-Fib upon exposure to periodontopathogens displayed upregulation of TLRs and release of cytokines (IL-1β, IL-6, and IL-8). In contrast, hESC-MSCs were largely nonresponsive to bacterial challenge, especially in terms of cytokine production. Further, exposure of hESC-Fib to A. actinomycetemcomitans serotype c was associated with higher IL-8 production than serotype b. In contrast, the hESC-MSCs displayed no serotype-dependent response. Differential response of the two hESC progenies implies a phenotype-dependent response to periodontopathogens and supports the concept of immunomodulatory properties of MSCs.