Type 2 diabetes as a risk indicator for dental caries in Korean adults: the 2011-2012 Korea national health and nutrition examination survey.

OBJECTIVES: The associations between type 2 diabetes (T2D) and untreated dental caries was examined. This study hypothesized that there would be a positive association between T2D and the prevalence of decayed permanent teeth (DT) in representative Korean adults. METHODS: The information was derived from the Korea National Health and Nutrition Examination Survey conducted in 2011-2012. Sociodemographic and lifestyle variables, anthropometric and biochemical status, metabolic health and glucose tolerance status, oral health behaviors, and dental caries index were evaluated. RESULTS: The number of DT had a positive association with degree of fasting plasma glucose (FPG) level, and glycated hemoglobin (HbA1c) (p-value = 0.045 and 0.007, respectively). The levels of FPG and HbA1c increased with the number of DT (p for trend = 0.009 and 0.004, respectively). The prevalence of untreated caries uncontrolled T2D participants was about 26% higher than those with normal glucose tolerance levels after adjusting for potential confounders including diets and socioeconomic status (OR [95% CI] = 1.26 [1.02, 1.56]). CONCLUSIONS: T2D is an independent risk indicator for untreated caries in Korean adults.

Obesity is inversely related to the risks of dental caries in Korean adults.

OBJECTIVE: This study investigated whether obesity is linked with dental caries. This study hypothesized that obesity may influence the number or prevalence of dental caries in Korean adults. SUBJECTS AND METHODS: Data were derived from Korea National Health and Nutrition Examination Survey performed at 2008-2010. Lifestyle, sociodemographic, and biochemical variables were analyzed. Indices related to obesity, sarcopenia, and metabolic syndrome were investigated. Finally, caries index and oral health behaviors were included for the analysis. RESULTS: The caries index was inversely associated with increasing body mass index (BMI) and body fat quartile (all p-values <.01). Subjects with high waist circumference who met the inclusion criteria of metabolic syndrome were less likely to have decayed tooth (p-value = .0009). Subjects with a BMI of 25 or more showed about 20% less prevalence of dental caries experience than normal individuals with a BMI of 18.5 to 23 glucose (odds ratio [95% confidence intervals] = 0.808 [0.684-0.956]). Similarly, subjects with total body fat in the highest quartile revealed about 20% less prevalence of caries experiences that those with body fat proportion in the lowest quartile (0.84 [0.672,1.049]). CONCLUSIONS: Obesity was inversely associated with occurrence or severity of dental caries in Korean adults.

Shear bond strength of four different repair materials applied to bis-acryl resin provisional materials measured 10 minutes, one hour, and two days after bonding.

This study investigated the shear bond strength of repaired provisional restoration materials 1) to compare the bond strengths between bis-acryl resin and four different materials and 2) to investigate the effect of the amount of time elapsed after bonding on the bond strength. The self-cured bis-acryl resin (Luxatemp) was used as the base material, and four different types of resins (Luxatemp, Protemp, Z350 flowable, and Z350) were used as the repair materials. Specimens were divided into three groups depending on the point of time of shear bond strength measurement: 10 minutes, one hour, and 48 hours. Shear bond strengths were measured with a universal testing machine, and the fracture surface was examined with a video measuring system. Two-way analysis of variance revealed that the repair materials (p<0.001) and the amount of time elapsed after bonding (p<0.001) significantly affected the repair strength. All of the repaired materials showed increasing bond strength with longer storage time. The highest bond strength and cohesive failure were observed for bonding between Luxatemp base and Luxatemp at 48 hours after bonding.

Laser modulation of heat and capsaicin receptor TRPV1 leads to thermal antinociception.

Er,Cr:YSGG lasers are used clinically in dentistry. The advantages of laser therapy include minimal thermal damage and the alleviation of pain. This study examined whether the Er,Cr:YSGG laser has in vivo and in vitro antinociceptive effects in itself. In capsaicin-evoked acute licking/shaking tests and Hargreaves tests, laser irradiation with an aerated water spray suppressed nociceptive behavior in mice. Laser irradiation attenuated TRPV1 activation by capsaicin in Ca(2+) imaging experiments with TRPV1-overexpressing cells and cultured trigeminal neurons. Therefore, the laser-induced behavioral changes are probably due to the loss of TRPV1 activity. TRPV4 activity was also attenuated, but limited mechanical antinociception by the laser was observed. The laser failed to alter the other receptor functions, which indicates that the antinociceptive effect of the laser is dependent on TRPV1. These results suggest that the Er,Cr:YSGG laser has analgesic effects via TRPV1 inhibition. Such mechanistic approaches may help define the laser-sensitive pain modality and increase its beneficial uses.

Biological responses in osteoblast-like cell line according to thin layer hydroxyapatite coatings on anodized titanium.

Several features of the implant surface, such as roughness, topography and composition play a relevant role in implant integration with bone. This study was conducted in order to determine the effects of various thin layer hydroxyapatite (HA) coatings on anodized Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on 100 nm HA (100 nm HA coating on anodized surface), 500-700 nm HA (500-700 nm HA coating on anodized surface), 1 mum HA (1 mum HA coating on anodized surface) and anodize (non-HA coating on anodized surface) Ti. The morphology of these cells was assessed by scanning electron microscopy (SEM). The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the four dental substrate types. MG63 cells cultured on 100 nm HA, 1 mum HA and anodize exhibited cell-matrix interactions. It was 500-700 nm HA surface showing cell-cell interaction. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein 2, latent transforming growth factor beta binding protein 1, catenin (cadherin-associated protein), integrin, PDGFRB and GDF-1 growth differentiation factor 1 were up-regulated on the different surfaces. Several genes, including fibroblast growth factor receptor 3, fibroblast growth factor 12 and CD4 were down-regulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface morphology of the dental materials used.

Effect of various implant coatings on biological responses in MG63 using cDNA microarray.

During the process of bone formation, titanium (Ti) surface is an important factor in the modulation of osteoblastic function. This study was conducted in order to determine the effects of different Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on smooth (S), sandblasted large-grit and acid etching (SLA), hydroxyapatite (HA), hydroxyfluoride (HF), titanium nitrate (TIN), and diamond-like carbon (DLC) Ti. The morphology of these cells were assessed by SEM. The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the six dental substrate types. The SLA and HA surfaces were determined to be rougher than the others. MG63 cells cultured on SLA and HA exhibited cell-matrix interactions. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein, cadherin, integrin, and insulin-like growth factors, were upregulated on the different surfaces. Several genes, including fibroblast growth factor receptor 4, Bcl 2-related protein, and collagen, were downregulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface roughness of the dental materials used.