[Effect of different cleaning methods on bond strength and surface wettability of high translucency zirconia].

PURPOSE: To study the effect of different cleaning methods on the shear bond strength of self-adhesive resin cement to saliva-contaminated high translucency zirconia and surface wettability. METHODS: Eighty zirconia specimens were randomly divided into 5 groups (n=16), i.e., control group(not contaminated), 75% ethanol group,cleaning paste group,airborne-particle abrasion group, and atmospheric pressure cold plasma group. The contact angles was measured, shear bond strength were examined, and fracture types were determined. SPSS 26.0 software package was used for statistical analysis of the data. RESULTS: The atmospheric pressure cold plasma group produced the lowest contact angle(P＜0.05). The shear bond strength of the airborne-particle abrasion group, the cleaning paste group and the atmospheric pressure cold plasma group respectively were similar to the control group without significant difference(P＞0.05), while those were significantly higher than 75% ethanol group(P＜0.05). The mixed fracture mode of the atmospheric pressure cold plasma group evidently increased. CONCLUSIONS: Airborne-particle abrasion, cleaning paste and atmospheric pressure cold plasma overcome the effects of saliva contamination, producing the shear bond strength to zirconia similar to the control group. The atmospheric pressure cold plasma improves hydrophilicity of high translucency zirconia significantly.

Anthocyanins-natural pigment of colored rice bran: Composition and biological activities.

Rice by-products are a potential source of various bioactive substances with great processing potential, which are receiving increasing attention. Among them, rice bran is a by-product of rice milling, with high nutritional value and health benefits. Colored rice bran contains a large amount of anthocyanins responsible for color and bioactivities. And anthocyanins are often added to foods as a natural pigment, serving to enhance both the visual appeal and nutritional value. Recent advances in the composition and bioactivities of four common colored rice bran anthocyanins (black, purple, red, and purple red rice) are reviewed in this paper. Rice bran anthocyanins have been confirmed to exhibit biological potential for human health, with their main biological activities being antioxidant, anti-atherosclerosis, anti-cancer, neuroprotective, retinoprotective, immunomodulatory, anti-aging and anti-obesity effects. The structure of anthocyanins determines their biological activities. The anthocyanins composition of rice bran with different colors varied greatly, while that of rice bran with the same color is also slightly different, which is attributed to the rice varieties, growing environment and cropping conditions. However, it remains necessary to conduct further clinical studies to support the health activities of anthocyanins. The present review provides information value for the further development and comprehensive utilization of rice bran anthocyanins.

[Effect of different dentin cleaning agents on the bond strength of self-adhesive resin cement to dentin].

OBJECTIVE: This study aims to evaluate the bond strength of a self-adhesive resin cement to dentin by ethylene diamine tetraacetic acid (EDTA) and NaClO. METHODS: Twenty-seven freshly extracted non-carious human premolars were prepared to expose the buccal dentin and randomly divided into three groups: control group (A group), EDTA group (B group) and NaClO group (C group). All teeth were bonded to dentin using a self-adhesive resin cement after the teeth in the A group were processed with distilled water. The B and C group were processed with 3%EDTA and 1%NaClO, respectively. After 24 hours at 37 °C water, the shear bond strengths of the twenty-four specimens were measured. All statistical analysis was performed using SPSS 17.0 software package. Each fractured specimen was examined under dental microscope. Three new specimens were cut, and the morphologies of the cement-dentin interface were observed under scanning electron microscope (SEM). RESULTS: The shear bond strength in the A group, B group and C group was (8.55±0.63), (8.47±0.56) and (12.97± 0.59) MPa, respectively. The difference between A group and B group was no statistically significant (P>0.05), whereas the difference between C group and B group (or A group) was statistically significant (P<0.05). SEM observation of the cement-dentin interface in the C group showed good adaptation, but resin tags were not observed. The other two groups showed poor bonding interface. Most of the fractured adhesive dentin surfaces exhibited cohesive failure in the A group and B group. All the fractured adhesive dentin surfaces exhibited cohesive failure in the C group. CONCLUSION: 1% NaClO can increase the bond strength of self-adhesive resin cement to dentin, but 3%EDTA has no effect.

[Clinical evaluation of denture adhesive combined with oral wetting spray on satisfaction of complete denture in xerostomia patients].

PURPOSE: The purpose of this study is to investigate the effect of denture adhesive and oral wetting spray on the satisfaction of wearing complete denture in xerostomia patients. METHODS: Ten edentulous patients who suffered from deficient residual alveolar ridge and xerostomia with poor retention and stability of complete dentures or mandibular complete dentures were employed to assess the differences of satisfaction after use of denture adhesive in their dry oral cavity for 1 week, and use of denture adhesive combined with oral wetting spray for 1 month, 3 months and 6 months by using satisfaction questionnaire. The statistical analysis was carried out with SPSS17.0 software package. RESULTS: Six months after the use of denture adhesive combined with oral wetting spray, the satisfaction of complete denture was significantly improved in respects of general satisfaction, retention of mandible denture, comfort and mastication improvement than that before application (P<0.05). But 1 week after the use of denture adhesive alone, the satisfaction of comfort reduced than that before application (P<0.05). CONCLUSIONS: Denture adhesive combined with oral wetting spray can be used to improve the satisfaction of xerostomia patients treated with complete denture who suffered from deficient residual alveolar ridge.

[Assessment of occlusal vertical dimension using angles: a pilot study].

OBJECTIVE: This study aims to identify highly accurate quantitative methods for evaluating the occlusal vertical dimension by using cephalometric radiographs to analyze the craniofacial hard tissue landmarks in 30 cases with normal occlusions. METHODS: A total of 30 subjects with normal occlusions and aged between 20 and 30 years old were included in the study. Cephalometric radiographs were obtained and analyzed using the Winceph 8.0 measurement software. Landmark points were identified and measured. RESULTS: The mean distribution difference of the center angle (CA) and lower angle (LA) of the face was not statistically significant (t = -1.490, P = 0.147). The CA and LA had a significantly linear correlation (r = 0.976, P = 0.000), and the regression equation was y = 0.298 + 0.997x. CONCLUSION: The CA can be used to assess and quantify the occlusal vertical dimension in clinical practice.