High-purity butoxydibutylborane catalysts enable the low-exothermic polymerization of PMMA bone cement with enhanced biocompatibility and osseointegration.

Polymethyl methacrylate (PMMA) based biomaterials have been widely utilized in clinics. However, currently, PMMA catalyzed by benzoyl peroxide (BPO) exhibits disquieting disadvantages including an exothermic polymerization reaction and a lack of bioactivity. Here, we first designed three industrial-scale synthesis methods for high-purity butoxydibutylborane (BODBB), achieving purity levels greater than 95% (maximum: 97.

Carbon footprints: Uncovering multilevel spatiotemporal changes of ship emissions during 2019-2021 in the U.S.

Quantifying and understanding changes in carbon emissions is essential for the U.S. shipping industry to reduce carbon emissions, especially after its return to the Paris Agreement.

Nickel-Catalyzed Selective C-H Cyanation via Aromatic Thianthrenium Salts.

Here, we report the first case of nickel-catalyzed C-H cyanation via arylthianthrenium salts. The reaction features the use of air-stable and inexpensive NiCl·6HO as a catalyst for the highly selective construction of cyanation products by aromatic pre-thianthrenation. The mechanism study shows that the formation of aryl radicals is involved.

Hemodynamic impact of snoring on carotid artery after stent implantation: the role of oscillation.

Snoring is common in overweight and elderly patients treated by endovascular stenting. Studies have proved a correlation between snoring and carotid stenosis, thus, snoring after carotid artery stenting (CAS) might promote or worsen clinical performance. This study tested this hypothesis by constructing a patient-specific carotid bifurcation model and numerically analyzing hemodynamic changes of the carotid artery under different snoring conditions.

[Three-dimensional finite element analysis of one-piece computer aided design and computer aided manufacture involved zirconia post and core].

Objective: To analyze the biomechanics trait of one-piece computer aided design and computer aided manufacture (CAD/CAM) zirconia post and core by the Three-dimensional finite element.

Methods: The Three-dimensional finite element models of three upper central incisors restored with one-piece CAD/CAM zirconia post and core (group 1), refabricated zirconia post and hot-pressed porcelain core (group 2), and cast gold alloy post and core (group 3) were built by geometry method respectively. 100 N vertical loading through the central incisor models long axis and 100 N loading along directing at an angle of 45° with the models long axis were used to imitate the central incisor stress state in biting and mandible physiological protraction movement.

[Comparison of soft and hard tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years].

Objective: To compare the peri-implant tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years.

Methods: In the study, 38 patients with single anterior tooth loss in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2010 to December 2011 were enrolled, and 43 implants were inserted. The gingival contour was induced using implant-supported temporary crowns prior to restoration till permanent prostheses delivered.

Evaluation of the therapeutic efficiency of mandibular anterior implant-supported fixed bridges with cantilevers.

Background: Dental implant technology has developed rapidly in recent years. However, the use of implant-supported fixed bridges with cantilevers has been controversial. The purpose of this study was to evaluate the clinical results of the mandibular anterior implant-supported fixed bridges with a cantilever.

[Evaluation of short-term clinical therapeutic efficiency of computer aided design and manufacturing titanium-ceramic-fixed partial dentures for implant-supported restoration in posterior region].

Objective: To evaluate the clinical results of computer aided design and computer aided manufacturing (CAD/CAM) titanium-ceramic-fixed partial dentures for implant-supported restoration in posterior region.

Methods: In the study, 90 patients (47 males, 43 females, and the mean age of 48.7 years ranging from 30-62 years) with posterior tooth missing underwent implant-supported porcelain fuse mental prostheses with CAD/CAM titanium-base.

Clinical follow-up of ceramic bridges with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects.

Background: Alternatives to the conventional auro-galvanoforming ceramic bridge need to be evaluated in long-term longitudinal studies before being recommended for restoration of dentition defects. This study aimed to evaluate the clinical performance of a ceramic bridge with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects.

Methods: In total, 114 ceramic bridges with auro-galvanoforming (primary coping and Ni-Cr pontic) were placed in 112 patients with dentition defects.

Fatigue cyclic loading test of an auro-galvanoforming ceramic bridge.

Background: In dental clinics, dentition defects are commonly restored with conventional porcelain-fused-to-metal fixed bridges. However, Ni-Cr alloy ceramic fixed bridges are known to have several drawbacks such as marginal coloration of the neck, low casting precision and, most seriously, poor biocompatibility. These problems could be circumvented by using noble metal ceramic bridges; however, one negative issue related to the conventional noble metal ceramic bridges is its high price due to the use of a large amount of gold for pontic.

[The 6-year clinical comparison of compound galvano-ceramic bridges with gold alloy and Ni-Cr alloy ceramic bridges].

Objective: To evaluate and compare effects of compound galvano-ceramic bridges with Ni-Cr alloy ceramic bridges and gold alloy ceramic bridges in clinic.

Methods: A total of 105 bridges were made for 103 patients. Of them, 35 were compound galvano-ceramic bridges, 35 Ni-Cr alloy ceramic bridges, and 35 gold alloy ceramic bridges respectively.

The evaluation of the carbon fiber post system on restoration of teeth defect in children.

Background: Post and post-core systems are used to restore extensively damaged teeth. Among these systems, cast alloy post and core, prefabricated threaded alloy post and prefabricated simple alloy post are most frequently applied in China nowadays. In Europe and North America a combined application of the fiber post, resin-core and crown has been applied to restore seriously destructed teeth with satisfactory results in recent years.

[The measurement and comparison of shear fracture strength and shear bond strength between carbon fiber post and some other posts].

Objective: The shear fracture strengths of carbon fiber post, IPS-Empress 2 all-ceramic post (without ZrO2 post), cast Ni-Cr alloy post, prefabricated zirconia ceramic post, human dentin and the shear bonding strengths of the first three kinds of post bonded in the human root canals were measured and compared, which are as the reference for dental clinic.

Methods: Standard cylindrical samples were made respectively in each group of carbon fiber post, IPS-Empress 2 all-ceramic post, cast Ni-Cr alloy post, prefabricated zirconia ceramic post, human dentin, three for each group. The shear fracture strengths of these samples were measured by universal testing machine (AUTOGRAPH DCS5000).