Antibody-functionalized polymer nanoparticle leading to memory recovery in Alzheimer's disease-like transgenic mouse model

Alzheimer's disease (AD) is a neurodegenerative disorder related, in part, to the accumulation of amyloid-β peptide (Aβ) and especially the Aβ peptide 1-42 (Aβ_1-42). The aim of this study was to design nanocarriers able to: (i) interact with the Aβ_1-42 in the blood and promote its elimination through the “sink effect” and (ii) correct the memory defect observed in AD-like transgenic mice. To do so, biodegradable, PEGylated nanoparticles were surface-functionalized with an antibody directed against Aβ_1-42. Treatment of AD-like transgenic mice with anti-Aβ_1-42-functionalized nanoparticles led to: (i) complete correction of the memory defect; (ii) significant reduction of the Aβ soluble peptide and its oligomer level in the brain and (iii) significant increase of the Aβ levels in plasma. This study represents the first example of Aβ_1-42 monoclonal antibody-decorated nanoparticle-based therapy against AD leading to complete correction of the memory defect in an experimental model of AD.     

Bio-Oss collagen and orthodontic movement for the treatment of infrabony defects in the esthetic zone

The aim of the present study was to evaluate whether it is possible to orthodontically move migrated teeth into infrabony defects augmented with a biomaterial. Three adult patients suffering from chronic periodontitis were treated. Each of the patients presented with an infrabony defect adjacent to a migrated maxillary central incisor. After cause-related therapy was completed, a surgical procedure was performed using the papilla preservation technique. The defects were filled with a collagen bovine bone mineral; after 2 weeks, an orthodontic device was activated using light, continuous forces. Orthodontic treatment time varied from 4 to 9 months; during this period, patients were enrolled in an oral hygiene recall program. At baseline and 6 months after the end of therapy, probing pocket depths (PPD) and clinical attachment levels (CAL) were assessed. In addition, the vertical and horizontal dimensions of the defects were measured on standardized radiographs. Residual mean PPD was 3.33 mm, with a mean reduction of 3.67 mm. Mean CAL gain was 4.67 mm. Radiologic vertical and horizontal bone fills were, on average, 3.17 mm and 2.0 mm, respectively. The present case series shows the effectiveness of a combined periodontic-orthodontic approach for the treatment of infrabony defects. Reduction of PPD to physiologic values, CAL gain, and radiologic defect resolution were obtained. No detrimental effects from the orthodontic movement were observed on the augmentation material.     

Warm gutta-percha obturation technique: a critical review

Cleaning and shaping the root canals play an important role to remove the organic debris within the endodontic system. The result, however, must be maintained over time through an effective root canal fillings preventing the entry of micro-organisms and tissutal fluid in the root canal system. Recently new materials have been introduced on the market, hence alternatives techniques for the root canals obturation have been developed and proposed. Even if cold lateral condensation is still considered the technique to refer to, there are numerous alternatives that use heat to achieve optimal adaptation of gutta-percha to the root canal space. The purpose of this work is to emphasize the positive aspect and points of weaknesses of different methods used for filling the root canals in order to allow the clinician to carry out choices as possible based on scientific evidence. Although many clinical trials still have not identified the superiority of one obturation technique over the others, the importance of this stage is objectively primary, so much that in the clinical practice we can notice an increasing success of endodontic treatment.     

Orthodontic movement into infrabony defects in patients with advanced periodontal disease: a clinical and radiological study

BACKGROUND: In cases of advanced periodontal disease with a pathologic flaring of frontal teeth, a combined periodontic-orthodontic therapy may be a reliable approach in order to solve both functional and esthetic problems. The aim of the present study was to evaluate the periodontal tissue alterations following periodontal surgery and orthodontic intrusion in migrated upper central incisors with intrabony defects. METHODS: Ten patients with advanced periodontal disease and an extruded maxillary central incisor infrabony defect at its mesial aspect and probing depth (PD) > or = 6 mm were included in the present study. At baseline, PD and clinical attachment level (CAL) were measured. The vertical and horizontal dimensions of the defects were assessed on standardized radiographs. Seven to 10 days after surgery the active orthodontic treatment started using the segmented arch technique, in order to intrude and move the teeth into the defects. Maintenance therapy was performed every 2 to 3 months until the orthodontic treatment was completed. RESULTS: At the end of treatment, mean PD reduction was 4.35 mm, with a residual mean PD of 2.80 mm. Mean CAL gain was 5.50 mm. The mean radiological vertical and horizontal bone fills were, respectively, 1.35 mm and 1.40 mm. All differences were of statistical significance (P<0.001). CONCLUSION: The present study showed that the combined orthodontic and periodontic therapy performed resulted in the realignment of extruded teeth with infrabony defects, obtaining a significant probing depth reduction, clinical attachment gain, and radiological bone fill.     

通过测定全血粘度及β-凝血球蛋白含量观察两种材料表面的抗血栓性能

本实验通过ex vivo法测定PDMS和PDMS/PU两种材料表面接触血流前后的全血粘度(表观粘度),结果显示:两组材料组的表观粘度均高于阴性对照组(P<0.01),而两材料组之间的表观粘度则无显著差异(P>0.05).通过测定两种材料表面接触人体血液后血浆中β-TG含量,结果表明:两组材料的β-TG含量均明显高于阴性对照组(P<0.001),而两材料组间的β-TG含量则无差别(P>0.05).两组实验结果均表明,PDMS和PDMS/PU表面未具备良好的抗血栓性能.