Effects of thermal cycling on bonding properties of novel low-shrinkage resin adhesive / 华西口腔医学杂志

OBJECTIVES@#The current study aimed to investigate the bonding properties of a novel low-shrinkage resin adhesive containing expanding monomer and epoxy resin monomer after thermal cycling aging treatment.@*METHODS@#Expanding monomer of 3,9-diethyl-3,9-dimethylol-1,5,7,11-tetraoxaspiro-[5,5] undecane (DDTU) as an anti-shrinkage additive and unsaturated epoxy monomer of diallyl bisphenol A diglycidyl ether (DBDE) as a coupling agent were synthesized. A blend of DDTU and DBDE at a mass ratio of 1∶1, referred to as "UE", was added into the resin matrix at the mass fraction of 20% to prepare a novel low-shrinkage resin adhesive.Then, the methacrylate resin adhesive without UE was used as the blank control group, and a commercial resin adhesive system was selected as the commercial control group. Moreover, the resin-dentin bonding and micro-leakage testing specimens were prepared for the thermal cycling aging treatment. The bonding strength was tested, the fracture modes were calculated, the bonding fracture surface was observed by scanning electron microscope (SEM), and the dye penetration was used to evaluate the tooth-restoration marginal interface micro-leakage. All the data were analyzed statistically.@*RESULTS@#After aging, the dentin bonding strength of the experimental group was (19.20±1.03) MPa without a significant decrease (P>0.05), that of the blank control group was (11.22±1.48) MPa with a significant decrease (P<0.05) and that of the commercial control group was (19.16±1.68) MPa without a significant decrease (P>0.05). The interface fracture was observed as the main fracture mode in each group after thermal cycling by SEM. The fractured bonding surfaces of the experimental group often occurred on the top of the hybrid layer, whereas those of the blank and commercial control groups mostly occurred on the bottom of the hybrid layer. Micro-leakage rating counts of specimens before and after thermal cycling were as follows: the experimental group was primarily 0 grade, thereby indicating that a relatively ideal marginal sealing effect could be achieved (P>0.05); meanwhile, the blank control group was primarily 1 grade, and the penetration depth of dye significantly increased after thermal cycling (P<0.05); the commercial control group was primarily 0 grade without statistical difference before and after thermal cycling (P>0.05), while a significant difference was observed between the commercial control group and experimental group after thermal cycling (P<0.05).@*CONCLUSIONS@#The novel low-shrinkage resin adhesive containing 20%UE exhibited excellent bonding properties even after thermal cycling aging treatment, thereby showing a promising prospect for dental application.

Correlation between intraplaque hemorrhage and new-onset embolic cerebral infarction after basilar artery angioplasty or stenting / 国际脑血管病杂志

Objective:To investigate the correlation between intraplaque hemorrhage (IPH) and new-onset embolic cerebral infarction after basilar artery angioplasty or stenting.Methods:Consecutive patients with severe basilar atherosclerotic stenosis underwent basilar artery angioplasty or stenting in the Department of Neurology, Guangdong Provincial Hospital of Chinese Medicine from January 2015 to February 2022 were retrospectively enrolled. High resolution magnetic resonance vessel wall imaging (HRMR-VWI) and diffusion-weighted imaging (DWI) were performed within one week before procedure, and brain DWI or CT examination was performed within 72 h after procedure to determine the patients with new-onset embolic cerebral infarction.Results:A total of 32 patients were enrolled in the analyze. IPH existed in 10 patients with basilar artery culprit plaque, and 5 had new-onset embolic cerebral infarction after procedure. The incidence of embolic cerebral infarction in the IPH group was significantly higher than that in the non-IPH group (50% vs. 0%; P=0.001). The proportion of patients with IPH in the embolic cerebral infarction group was significantly higher than that in the non-embolic cerebral infarction group (100% vs. 18.5%; P=0.001). Conclusion:IPH may be associated with new-onset embolic cerebral infarction after basilar artery angioplasty or stenting.

The effects of viscosity and volume on swallowing, penetration and aspiration in persons with post-stroke dysphagia / 中华物理医学与康复杂志

Objective:To explore the effect of swallowing different viscosities and volumes on the swallowing of dysphagic stroke survivors, and also penetration and aspiration.Methods:A total of 59 stroke survivors with dysphagia were evaluated using videofluoroscopy while completing the Chinese version of the volume viscosity swallow test. They were required to swallow 3, 5 and 10ml of food of medium, low, zero and high viscosity. Modified barium swallowing impairment profiles (MBSImPs) and the Rosenbek penetration aspiration scale were used for quantitative analysis.Results:Tongue control, initiation of the pharyngeal swallow and larynx closure showed the worst performance when swallowing zero-viscosity food. Oral residue performance was poor when swallowing large volumes and pharyngeal peristalsis was poor with small volumes. The risk of penetration and aspiration was greater with low-viscosity, large-volume swallowing tasks. There was a significant positive correlation between the penetration aspiration grade and total pharyngeal score. Larynx closure was especially strongly correlated with the penetration aspiration grade.Conclusions:The characteristics of physiological swallowing are closely related to the viscosity and volume of the material being swallowed. The risk of penetration and aspiration is greater with large volumes of low-viscosity food.