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Background. In this study antimicrobial effect of ethanolic and aqueous extracts of Juglans regia bark in Iran was evaluated on four different oral bacteria, Streptococcus mutans, Streptococcus salivarius, Streptococcus sanguis, and Staphylococcus aureus. Methods. Aqueous and ethanol extracts of Juglans regia bark were prepared by using disk diffusion technique and Minimal Inhibitory Concentration (MIC) methods. Tetracycline 30 μg and Erythromycin 15 μg were used as positive control and water as negative control in disk diffusion and MIC methods. Data were analyzed by ANOVA test. Results. The results showed that S. sanguis and S. mutans were the most sensitive and the most resistant bacteria against ethanolic and aqueous extracts, respectively. Ethanolic extract had significant antibacterial effect against all tested bacteria. Aqueous extract did not show antibacterial effect on S. mutans, in contrast to ethanolic extract. Aqueous extract had significantly antibacterial effect against Staphylococcus aureus, S. salivarius, and S. sanguis compared to control (P < 0.0001), but it did not show effect on S. mutans when compared with Erythromycin. According to the obtained MIC values, ethanol extract of Juglans regia bark had the lowest rate. Conclusion. The results may provide the basis for using natural antimicrobial substance for oral hygiene prophylaxis purposes.

Background: Salivary secretory IgA (sIgA) is said to play an important role in the immune response against dental caries. This study aimed to determine the salivary sIgA levels in healthy smokers and non-smokers, and its correlation with dental caries. Methods: A total of 70 healthy subjects were selected and classified into four groups according to dental caries and tobacco smoking habits: smoking with caries (Group 1, n = 15); smoking without caries (Group 2, n = 15); non-smoking with caries (Group 3, n = 15); and non-smoking without caries (Group 4, n = 25). Salivary sIgA was measured using ELISA. The fissure and proximal caries were examined clinically and radiographically. Caries status was determined according to the decay surface index. Results: Smokers showed a higher number of caries and the lowest concentration of sIgA. The highest levels of sIgA were observed in non-smoking and caries-free subjects compared to caries-active smokers (123.2 AE 19.9 vs. 13.3 AE 4.1 lg/ml respectively, p < 0.001). Also, the mean level of sIgA in Group 4 was significantly higher than Group 3 (p = 0.009). More importantly, higher and significant levels of sIgA were found in Group 3 versus Group 1 (p < 0.0001) and Group 2 (p = 0.0004). Conclusions: Our findings indicate that low concentrations of salivary sIgA are correlated with a higher prevalence of dental caries in smokers.

Background:Periodontitis is a local chronic inflammatory condition of the supporting structures of the teeth resulting from a dental plaque biofilm attached to teeth surfaces. Recent studies have indicated that this oral disease may have effects on systemic health.Objectives:The aim of the present study was to evaluate the association between periodontitis and hyperlipidemia.Patients and Methods:This case-control study was conducted in Iran during March 2011. In this case-control study, levels of serum lipids in 45 subjects with periodontitis were measured and compared with 45 age, gender and body mass index (BMI) matched controls. Data were analyzed using student t-test and chi-square test with P < 0.05 as the limit of significance.Results:Mean values of total cholesterol (CHL) (periodontitis group = 218.11 ± 29.77, control group = 162.31 ± 48.24) and triglycerides (TG) (periodontitis group = 209.77 ± 44.30, control group = 125.60 ± 44.16) were significantly higher in the periodontitis group (P < 0.001). High-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol levels were higher in the case group, but this difference was not statistically significant. Frequency of pathological values of CHL and TG were significantly higher in cases compared with the controls (P = 0.002 and P = 0.015, respectively).Conclusions:This study indicates that hyperlipidemia may be associated with periodontal disease in healthy individuals; yet whether periodontitis causes an increase in levels of plasma lipids or whether hyperlipidemia is a risk factor for periodontal infection and cardiovascular disease, it needs further investigations.

Background To evaluate shear bond strength of zirconia to composite resin using different universal and conventional adhesives and a zirconia primer. Material and Methods Forty zirconia blocks were fabricated of zirconium ingots (10×10×5 mm) and sintered at 1530°C for 2 hours. They were then air-abraded with Al2O3 particles. The specimens were divided into 4 groups and subjected to one of the following bonding agents: Futurabond U (group 1), Clearfil Universal Bond, universal adhesives (group 2), Z-Prime Plus, zirconia primer (group 3) and Adper Single Bond 2, conventional adhesive (group 4). Composite resin was then applied in a diameter of 5 mm and in a thickness of 2 mm. All the specimens were stored in distilled water at 37°C for 24 hours and then thermocycled between 5°C and 55°C for 5000 cycles with a 30-second dwell time. The shear bond strength was then evaluated with a universal testing machine at a crosshead speed of 1 mm/min. Data (MPa) were analyzed using ANOVA and LSD test ( P ≤0.05). The specimens were evaluated under a stereomicroscope to determine the mode of failure. Results The mean shear bond strength was 16,874 MPa in group I, 13.4434 MPa in group II, 11.6500 MPa in group III and 6.8700 MPa in group IV. ANOVA revealed that the shear bond strength in group IV was significantly lower than that in other groups ( P ≤0.05). Conclusions The shear bond strength in group I was significantly higher than that in groups III and IV. So Universal adhesives could provide higher shear bond strength of zirconia to composite resin after thermocycling compared to zirconia primers. Key words: 10-MDP, shear bond strength, universal adhesive systems, zirconia primer.