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Impacted Maxillary Canines: A Review
Published in Niall MH McLeod, Peter A Brennan, 50 Landmark Papers every Oral & Maxillofacial Surgeon Should Know, 2020
Alice Cameron, Serryth Colbert
Some techniques described in this paper are no longer routinely performed, either because they had a weak evidence base or have been superseded by techniques with a more rigorous evidence base. This paper discusses surgical exposure to allow natural eruption to occur and the placement of a polycarboxylate crown onto the impacted tooth, post-exposure. This is infrequently carried out in current practice and has been replaced with techniques such as apically repositioned flaps or open exposure. Similarly, a two-step approach is discussed for the surgical exposure and placement of an auxiliary attachment, where the canine is surgically uncovered and immediately packed with a surgical dressing. Pack removal occurs after 3–8 weeks when the attachment was placed.3
Virtual diespacing—Everest® (Kavo®) system evaluation
Published in R.M. Natal Jorge, J.C. Reis Campos, Mário A.P. Vaz, Sónia M. Santos, João Manuel R.S. Tavares, Biodental Engineering IV, 2017
P. Rocha-Almeida, J.C. Reis Campos, T. Coutinho Almeida, P. Vaz, C. Silva, J.C. Sampaio-Fernandes
Prosthetic cementation is a step of major importance in the prosthesis retention (Melo Freire et al. 2016). Zinc phosphate cement is easy to handle, has a good compression resistance, a reasonable work time and an acceptable film thickness (25 μm). Zinc oxide cement without eugenol has good consistency, is easy to handle, has a thin film thickness and a compression resistance lower than other cements. Polycarboxylate cements have chemical adhesion to enamel and dentin, acceptable film thickness, low compression resistance but high traction resistance.
Radiometallo-Labeled Peptides in Tumor Diagnosis and Therapy
Published in Astrid Sigel, Helmut Sigel, Metal Ions in Biological Systems, 2004
Mihaela Ginj, Helmut R. Maecke
Unlike the acyclic analogs, the polyazamacrocyclic polycarboxylate ligands provide a higher degree of rigidity to the resulting metal complexes, and therefore improved kinetic inertness in vivo [14]. The DOTA-based BFCs (Figure 5 a-c) continue to be the most widely studied ligands for linking trivalent metallic radioisotopes to biomolecules [22–25]. The most common method involves the attachment of the peptide to one of the four acetate groups via a CO-NH bond. This conjugation can be made either via an activated ester of one carboxylate group, like NHS esters (Figure 5a), or using a monoreactive DOTA prochelator like DOTA(tBu)3 (Figure 5b) [26]. The prochelator approach is perfectly compatible with peptide synthesis in solid phase or in solution and DOTA(tBu)3 was coupled to somatostatin analogs with 65 ± 5 % yields after deprotection and purification. DOTA, used unprotected, was also coupled to the same peptide with about 40 % overall yield [26].
A systematic review on the accuracy of zirconia crowns and fixed dental prostheses
Published in Biomaterial Investigations in Dentistry, 2020
There is no consensus on what is regarded as clinically acceptable fit, for marginal fit several authors suggest ∼100 μm [1,3–6]. For internal fit, McLean and von Fraunhofer considered 120 μm clinically acceptable for dental restorations cemented with polycarboxylate cement [1,5]. Even though the internal discrepancies may be well over 200–300 μm most authors conclude that the results from their in vitro fit studies are clinically acceptable when the mean marginal gap is below or close to 120 μm [7–11]. The tooth-crown interface is divided into different areas; marginal, chamfer, axial, and occlusal. There are several areas or distances used to assess the marginal fit of the restoration, it can be measured as the marginal gap, the vertical marginal discrepancy, the horizontal marginal discrepancy, and the absolute marginal discrepancy [12]. The internal fit can be divided into discrepancy at the chamfer or cervical area, axial discrepancy and occlusal discrepancy, or as a mean of all the measuring areas/points [13,14].
Zinc-based metal–organic frameworks as nontoxic and biodegradable platforms for biomedical applications: review study
Published in Drug Metabolism Reviews, 2019
Sonia Bahrani, Seyyed Alireza Hashemi, Seyyed Mojtaba Mousavi, Rouhollah Azhdari
Biocompatibility of MOFs is more characterized by types of organic linkers. Obtained MOFs from endogenous ligands which originated from constitutive components of body composition, in particular, those based on amino acids such as bioMOF-1, Zn-adenante-MOFs or Zn-MOF based on phenylalanine and tyrosine derivatives are more preferred (Gu et al. 2015). In fact, these bio MOFs may be reused in the body and significantly reduce the risk of adverse effects. Exogenous ligands such as polycarboxylates, imidazolates, pyridyl, and amines, which are prepared from natural compounds were also substantial in bio application without changing the body cycles (Wu and Yang 2017; Sun et al. 2013). Recently, Restrepo et al. (2017) showed the remarkable antibacterial behavior of the Zn-based MOF prepared with 4-hydrazinebenzoic acid toward the Staphylococcus aureus bacterium which attributed to the controlled release of the ligand. Hence, the application of Zn-based MOFs as drug delivery or antibacterial agents depends on their low cytotoxicity profiles (Bhardwaj et al. 2018).
The toxicology of air pollution predicts its epidemiology
Published in Inhalation Toxicology, 2018
Andrew J. Ghio, Joleen M. Soukup, Michael C. Madden
The interaction between air pollution particles and ozone is suggested to impact human health effects (Figure 2(A)). Air pollution particles include a significant concentration of HULIS (i.e. polycarboxylates), and investigation predicts further carboxylation of this PM following ozone exposure. This results in a particle with a greater capacity to impact (1) iron sequestration resulting in an increased disruption in metal homeostasis and (2) subsequent inflammation and fibrosis. Damage induced by ozone-reacted HULIS is in addition to lung cell injury associated with ozone exposure, which may or may not be a different type of injury and may make the cells more sensitive. Such interaction between particles and ozone is supported by epidemiological, controlled exposure, animal, and in vitro investigation (Bosson et al., 2008; Chen et al., 2007; Jakab & Hemenway, 1994; Kafoury & Kelley, 2005; Madden et al., 2000, 2014; Molhave et al., 2005; Stiegel et al., 2016). Furthermore, it is possible that other components of air pollution (e.g. nitrogen oxides) also participate in modifying the functional groups at the ambient PM surface and subsequently impact human health through the same pathway (Ciobanu et al., 2016). Finally, an additional source of HULIS production could be photooxidation from ultraviolet radiation, which would result in changes comparable to ozone exposure.