The coacervation process of Graham’s Salt Na(PO
3
)
n
enabled the preparation of polyphosphate coacervates (CPPs) by adding different metallic ions (M
n+
), and/or low-molecular-weight solvents at a ...specific solution, which resulted in a phase separation. The more viscous phase is termed as CPP and the less viscous one is the supernatant. CPPs have been extensively studied in recent years as a glass precursor at room temperature. Preparation at room temperature allows the preservation of the physicochemical properties of a wide range of active principles that may be used in controlled drug-delivery systems. Despite the present limitations of CPPs in terms of high hygroscopicity, this vulnerability to water is considered one of the great advantages of this material regarding applications in the controlled release of drugs and tissue engineering. Thus, in the presence of water, CPPs will dissolve in calcium and phosphate ions, which are the major inorganic constituents of bone and hydroxyapatite (HAP). It is believed that, in contact with body fluids, CPPs will degrade and, as this process occurs, they will be replaced by HAP. Therefore, CPPs configure a potential biomaterial that offers excellent properties with a wide range of biomedical applications that will be discussed and reviewed in this paper, including the structural properties and the recent improvements of materials based on CPPs and related devices.
Highlights
The Polyphosphates Coacervates (CPPs) can be used as soft Glass-Materials precursors.
The coacervation process of polyphosphate solution enables the preparation of CPPs.
CPPs are biocompatible and allow the development of biomedical and pharmaceutical materials.
CPPs can be applied in drug delivery systems and radiopaque resorbable.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Objective
To evaluate the accuracy of facial measurements on three‐dimensional images obtained using a new photogrammetric scanner.
Material and Methods
A total of 11 participants were included in ...the study. Nine customized adhesive labels were used to identify the facial landmarks: Trichion (Tri), Glabella (G), Right (Exr) and Left (Exl), Pronasal (Pn), Subnasal (Sn), Chelion right (Chr) and left (Chl) and Mentonian (Me). Two trained and calibrated examiners were responsible for performing seven linear measurements for each participant (Tri‐G, Sn‐Me, Exr‐Exl, Chr‐Chl, Exr‐Chr, Exl‐Chl, Pn‐Sn) first with a digital caliper and later with a three‐dimensional model obtained after digitalization with photogrammetric technology. The intraclass correlation coefficient (ICC), mean difference, SD, and Bland–Altman correlation were used to compare the measurements performed.
Results
Intra and inter‐examiner reliability were excellent (ICC >0.9). In general, the measurements presented a variation of a minor 2.0 mm. However, only three measures (Sn‐Me, Exr‐Exl, and Exr‐Chr) were outside the clinical acceptability range.
Conclusions
The 3D Cloner scanner showed clinically acceptable accuracy comparable to the digital caliper with a variation of −0.8 ± 1.2 mm. Inter‐ and intra‐examiner agreement on digital measurements was also observed.
Clinical Significance
Scanners with accurate 3D model reproductions associated with reliable digital measurements provide a more precise diagnosis and better planning in orofacial treatment.
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BFBNIB, CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The aim of the study was to evaluate the chemical composition and radiopacity of new calcium-silicatebased cements. Discs of 10 mm x 1 ± 0.1mm were prepared of BiodentineTM, TheraCal, Dycal and GC ...Fuji IX (n=5). The samples were radiographed directly on an PSP occlusal plate adjacent to an aluminium step wedge. The radiopacity of each specimen was determined according to ISO 9917/2007. Statistical analyses were carried out using ANOVA and Tukey’s test at a significance level of 5 %. The chemical constitution of materials was determined by scanning electron microscopy (SEM) and energy dispersive x-ray element mapping. The radiopacities of the materials in decreasing order were: GC Fuji IX (3.45 ± 0.16 mm), Dycal (3.18 ± 0.17), BiodentineTM (2.79 ± 0.22), and TheraCal (2.17 ± 0.17). TheraCal showed the lowest radiopacity compared to the other materials, followed by BiodentineTM. Dycal and GC Fuji IX radiopacity values did not present significant statistical differences. Scanning electron microscopy and energy dispersive X-ray analysis revealed the presence of zirconium in BiodentineTM; and strontium, barium and zirconium in TheraCal as radiopacifying elements. The new calcium silicate cements present distinctive chemical composition. BiodentineTM contains zirconium as a radiopacifying element and has higher radiopacity values than TheraCal, which contains barium and strontium as radiopacifiers.
Introduction: global mobilization has created new needs. From sporting events to criminal matters, determining the chronological age of individuals is being used by forensic surgeons worldwide. The ...objective of the present study was to analyze the forensic methods to estimate the age of individuals, including the advantages and limitations of these methods. Method: a search was conducted in the Sistema de Bibliotecas de la Universidad Mayor (SIBUM): Dentistry & Oral Sciences Source, ClinicalKey, and Science Direct Freedom Collection, selecting papers published from 1980 to 2014. A manual search was also conducted, including specific journals and texts in this field, with no limitation as to the year of publication. The inclusion criteria were research projects aimed at determining the chronological age of individuals through forensic analysis of oral tissues. All published texts in a language other than English were excluded. In total, 70 publications were analyzed. Technological advances have paved the way for the study of new parameters; however, the original ones identified by Gustafson in 1950 are still studied. Conclusions: most studied methods are invasive in some degree. In addition, none of these techniques is accurate in its own; therefore, the combination of different measurement techniques is recommended, opening a field of research on techniques that are less invasive and can be a complement to the existing ones. Finally, the available information lead to conclude that research on populations of African and Asian descent is lacking, which is a current challenge because of globalization, migration, and the heterogeneity of current populations.
Introduction: the goal of this literature review is to analyze the findings included in the literature concerning different alternatives to increase longevity of resin-based composite restorations ...and their adhesive bond. Methods: bibliographies in the EBSCO database (Elton B Stephens Company) were reviewed using the following key words: "composite repair bond strength"; "restorations sealing"; composite restorations longevity"; "restorations refurbishment"; "composite bond strategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength"; "multiple layer dentin bond strength", and "dentin adhesive evaporation bond strength". Clinical and laboratory results were analyzed in terms of repairing, sealing, and refurbishing defective restorations, in addition to improvements in impregnation of adhesive surfaces, resistance of adhesive polymers, and the progress recently made concerning resistance to hydrolytic collagen degradation. Results: repairing, sealing, or refurbishing defective restorations allow keeping tooth structure healthy, reducing potential damage to dental pulp, as well as operatory pain, often caused without anesthetics. New bonding management techniques provide adhesive procedures with increased longevity. Conclusions: repairing, refurbishing, or sealing defective composite resins increase the longevity of restorations and restored teeth by using minimally invasive dental techniques. Other methods, such as improving impregnation of adhesive surfaces, increasing adhesive polymers strength, and hydrolytic degradation of collagen are promising advances that modify the management of bonding techniques, providing patients with restorative treatments of increased longevity.
The aim of this prospective, blind, and randomized clinical trial was to assess the effectiveness of repair of localized clinical defects in amalgam restorations that were initially scheduled for ...replacement. A cohort of 20 patients with 40 (Class I and Class II) amalgam restorations that presented one or more clinical features that deviated from the ideal (Bravo or Charlie) according to US Public Health Service criteria, were randomly assigned to either the repair or the replacement group-A: repair, n = 19; and B: replacement, n = 21. Two examiners who had calibration expertise evaluated the restorations at baseline and 10 years after according to seven parameters: marginal occlusal adaptation, anatomic form, surface roughness, marginal staining, contact, secondary caries, and luster. After 10 years, 30 restorations (75%) were evaluated (Group A: n = 17; Group B: n = 13). Repaired and replaced amalgam restorations showed similar survival outcomes regarding marginal defects and secondary caries in patients with low and medium caries risk, and most of the restorations were considered clinically acceptable after 10 years. Repair treatment increased the potential for tooth longevity, using a minimally interventional procedure. All restorations trend to downgrade over time.
The objective of this study was to clinically evaluate sealed composite restorations after 10 years and compare their behavior with respect to controls.
The cohort consisted of 20 patients aged 18 to ...80 years with 80 composite restorations. All participants in the sealing and no-treatment groups presented with clinical features for the marginal adaptation that deviated from the ideal and were rated Bravo (United States Public Health Service criteria). Composites with Alfa values for the marginal adaptation were used as the positive control.
The marginal adaptation behavior was similar between the sealing and control (+) groups, with a high frequency of Bravo values in the 10th year (80% and 51%, respectively). Most of the no-treatment (-) group maintained the Bravo values (91%) for 10 years, although some restorations (9%) progressed to Charlie values. The anatomy parameter differed significantly between the first and 10th years, with deterioration in all three groups (p<0.05). The secondary caries parameter had a similar behavior in the three groups (p>0.05).
Sealing the margins of the composite resin restorations had no significant effect compared with the control groups, under the conditions of this study. Sealing the restorations substantially improved the marginal staining and marginal adaptation parameters, although by the tenth year they were similar to the group without intervention.
Seventy-two male albino rats received autogenous transplants of glycerol-preserved rib cartilage into the malar process. The animals were divided into two groups which received preserved cartilage ...with or without perichondrium. The implants were well tolerated and removal of the perichondrium enhanced the rate of resorption and bone replacement of the material.
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