40 research outputs found
Direct versus Indirect Techniques to Menage Uncomplicated Crown Fractures of Anterior Teeth Following Dentoalveolar Trauma
No full textDental trauma are the most common reasons for dental fractures in the anterior area, they have an incidence of 5% in the population, and in permanent teeth, they are mainly caused by sports. The most involved teeth are the maxillary anterior teeth. Direct composite restorations and indirect ceramic restorations are the therapy of choice for restoring anterior teeth after fracture when is not possible to reattach the tooth fragment. The treatment options in uncomplicated coronal fractures depend on various factors such as the amount of residual dentinal enamel tissue, the relationship with the gingival profiles, and the age of the patient. The purpose of this article is to discuss the option of using direct or indirect restorative techniques in the treatment of traumatically fractured anterior teeth and to analyze the advantages and disadvantages of the two methods
La terapia fotodinamica antimicrobica nel trattamento della perimplantite. Studio clinico controllato
No full textLa terapia della perimplantite è rivolta al controllo dell’infezione, alla decontaminazione della superficie implantare e al ripristino della condizione di salute. La decontaminazione delle superfici implantari tuttavia risulta complicata. Obiettivo di questo studio è quello di valutare se la terapia fotodinamica antimicrobica possa rappresentare un supporto efficace ai metodi convenzionali nel trattamento di questa condizione patologica infiammatoria
Complex Implant-Prosthetic Rehabilitation Following Sports Trauma with 14 Years of Follow-Up: Case Report
No full textTooth loss after traumatic dental injuries (TDI) often requires rehabilitation with a multidisciplinary treatment plan. In growing patients, the therapeutic approach may be different than in adults; the scientific literature offers alternative solutions even if they involve long, complex and uncomfortable treatments. Among the possible therapeutic options, implant-prosthetic treatment through the use of mini-implants is presented in this complex case report with a 14-year follow-up
The occlusal precision of milled versus printed provisional crowns
No full textObjectives: The aim of this study was to compare the occlusal precision of computer-aided-design/ computerassisted-manufacturing (CAD/CAM) milled versus 3D printed polymethylmethacrylate (PMMA) temporary prosthetic crowns , starting from the same digital CAD design. Materials and methods: The study sample included 34 patients presenting 34 premolars in need of prosthetic rehabilitation: a total of 68 temporary crowns were manufactured, 34 of which milled and 34 printed. Immediately after manufacturing, the milled and printed provisionals were scanned with a desktop scanner (E1, 3Shape) to obtain STL files, that were superimposed to the original CAD design in order to identify the occlusal trueness (Analysis A). A second occlusal comparison was performed by scanning both kind of provisional after being placed intraorally with Trios scanner (3 Shape); intraoral scans were obtained in order to compare STL files of provisionals before and after occlusal adjustments (Analysis B). The occlusal trueness was identified at three reference points, P1 (vestibular cusp), P2 (palatal / lingual cusp), P3 (central fossa). The statistical analysis was performed using the R 3.4.3 statistical software (The R Foundation for Statistical Computing), with a significance level of p <0.05. Results: Overall, the printed crowns showed lower occlusal differences than the milled crowns, when compared to the CAD design file, with a statistically significant difference in P1 (difference of 0.025 +/- 0.046 mm), P2 (difference of 0.027 +/- 0 0.044 mm) and P3 ( difference of 0.018 +/- 0.050) for Analysis A (p <0.05). In the Analysis B the direct comparison between the degree of average difference between the pre-adjustment and the post-occlusal adjustment of the milled and printed crowns shows that the printed crowns have lower occlusal mean difference values in all three points compared to the milled ones (difference of 0.146 +/- 0.273 mm in P1, 0.285 +/- 0.360 mm in P2 and 0.257 +/- 0.277 mm in P3). Conclusions: Within the limitation of this study, the data obtained showed a better occlusal surface dimensional accuracy of the 3D printed provisional crowns, when compared to the milled ones. Comparing the results obtained, it is possible to assume that the intraoral scans also had a contribution to occlusion, beside the manufacturing method. 3D printing can be successfully applied for manufacturing temporary PMMA crowns
Hyperfine splitting of [Al VI] 3.66 mu m and the Al isotopic ratio in NGC 6302
No full textThe core of planetary nebula NGC 6302 is filled with high-excitation photoionized gas at low expansion velocities. It represents a unique astrophysical situation in which to search for hyperfine structure (HFS) in coronal emission lines from highly ionized species. HFS is otherwise blended by thermal or velocity broadening. Spectra containing [Al vr] 3.66 mu m P-3(2) <- P-3(1), obtained with Phoenix on Gemini South at resolving powers of up to 75000, resolve the line into five hyperfine components separated by 20-60 km s(-1) as a result of the coupling of the I = 5/2 nuclear spin of Al-27 with the total electronic angular momentum J. The isotope Al-26 has a different nuclear spin of I = 5, and a different HFS, which allows us to place a 3 sigma upper limit on the Al-26/Al-27 abundance ratio of 1/33. We measure the HFS magnetic dipole coupling constants for [Al vr], and provide the first estimates of the electric quadrupole HFS coupling constants obtained through astronomical observations of an atomic transition
Análise funcional e estrutural da proteína Pub 1 de Saccharomyces cerevisiae
No full textA expressão gênica pode ser regulada em eucariotos em diversas etapas dometabolismo de mRNA, como transcrição, processamento, tradução e degradação. A estabilidade de mRNA é modulada por elementos presentes no transcrito e por proteínas ligantes de RNA associadas a esses elementos. Pub1 de S. cerevisiae é uma proteína citoplasmática capaz de estabilizar transcritos contendo elementos ricos em AU (ARE e ARE-like) ou elementos estabilizadores (STE). O presente trabalho identificou num rastreamento de duplo-híbrido a proteína Nab2 como ligante de Pub1. Nab2 é uma proteína nucleocitoplasmática essencial que regula o comprimento da cauda poli(A) e a exportação nuclear de mRNA. A interação entre Pub1 e Nab2 foi confirmada por co-purificação e ensaio de interação in vitro. Foi demonstrado também que essa interação é mediada pelo domínio de dedos de zinco presente na região C-terminal de Nab2. A análise da relação funcional entre essas duas proteínas revelou que Nab2, assim como Pub1, é capaz de modular a estabilidade de mRNA. A estabilidade do transcrito de RPS16B, mensageiro contendo sequência ARE-like e regulado por Pub1, é diminuída nos mutantes nab2- 1 e nab2-67. No entanto, a estabilidade do transcrito de GCN4, mensageiro contendo STE e também regulado por Pub1, não é afetada nos mesmos mutantes. Resultados semelhantes foram observados para outros transcritos contendo sequências ARE-like ou STE. Ainda, dados obtidos com um mutante da via NMD (?upf1) mostraram que esta via de decaimento não está envolvida com o mecanismo de estabilização de RPS16B mediada por Pub1 e Nab2. Uma análise mais profunda mostrou que a sequência ARE-like presente no mensageiro de RPS16B é necessária para a estabilização mediada por Nab2. A proteína Pub1 e seus domínios isolados foram produzidos e purificados, mas não foi possível a obtenção de cristais para...Regulation of gene expression can occur at different levels of mRNA life cycle, including transcription, processing, translation and degradation. mRNA stability is modulated by elements in the mRNA transcript and their cognate RNA-binding proteins. Poly(U)-binding protein 1 (Pub1) is a cytoplasmic S. cerevisiae mRNA binding protein that stabilizes transcripts containing AU-Rich Elements (ARE and ARE-like) or Stabilizer Elements (STE). In a yeast two-hybrid screen, we identified Nuclear poly(A)-binding protein 2 (Nab2) as a Pub1-interacting protein. Nab2 is an essential nucleocytoplasmic shuttling mRNA binding protein that regulates poly(A) tail length and mRNA export. The interaction between Pub1 and Nab2 was confirmed by co-purification and in vitro binding assays. The interaction is mediated by the Nab2 zinc finger domain. Analysis of the functional link between these proteins reveals that Nab2, like Pub1, can modulate the stability of specific target mRNA transcripts. We find that the half-life of the RPS16B transcript, an ARE-likecontaining Pub1 target, is decreased in both nab2-1 and nab2-67 mutants. In contrast, GCN4, an STE-containing Pub1 target, is not affected. Similar results were obtained with other ARE- and STE-containing Pub1 target transcripts. Additionally, results obtained with a mutant of the NMD pathway (?upf1) showed that this pathway is not involved in the mechanism of RPS16B stabilization mediated by Pub1 and Nab2. Further analysis reveals that the ARE-like sequence is necessary for Nab2- mediated transcript stabilization. Full-length Pub1 and isolated domains were produced and purified, however, it was not possible to obtain protein crystals for tertiary structure determination. Taken together, these results suggest that Nab2 acts together with Pub1 to modulate mRNA stability and strengthen a model where nuclear events involved in mRNA biogenesis...(Complete abstract click electronic access below)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Acquired white oral lesions with specific patterns: Oral lichen planus and lupus erythematosus
No full textBackground: Diagnosis of oral white lesions might be challenging. These lesions represent a wide spectrum of diseases with different etiology and prognosis. Oral white lesions can be categorized into two major groups, congenital and acquired, according to their development, and in four subgroups: lesions which can be scraped off or not and lesions with special pattern or not. Objectives: The aim of this manuscript is to review, from diagnosis to treatment, the current knowledge on oral white lesions with specific pattern. Methods: A review on oral white lesions with specific pattern was conducted on PubMed and Scopus from inception to January 2021. Results: Among acquired lesions with specific pattern two clinical entities are mostly represented: Oral lichenoid reactions and Lupus erythematosus. The etiology of both diseases is still not known but their pathogenesis is mainly immunological. At present the mucoscopic features of those disease have been described only in few case reports or case series. Immunomodulatory therapies are often the agents of choice for their treatment. Conclusions: The collaboration of dermatologists and dentists as a team is important for early diagnoses and effective treatments. Mucoscopy is a promising technique which may reveal important features for the differentiation of OLP and LE oral white lesions
Rehabilitation of a patient with mini‐implants after avulsion of the upper incisors: A 13‐year follow up
No full textCO IN THE CARBON STAR IRC+10216
No full textAuthor Institution: Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721We report the detection of CO in the circumstellar envelope of IRC+10216. Five rotational lines of this molecule were observed at 2 and 3 mm using the Kitt Peak 12 m telescope of the Arizona Radio Observatory (ARO). The line profiles were U-shaped, indicating that the molecule is present in the outer shell with a source size 81.6''. The derived CO column density of 1x10 cm is two orders of magnitude larger than the value predicted by the most recent chemical model of IRC+10216 (Millar, Herbst \& Bettens 2000). CO is the sixth oxygen-bearing molecule that has been identified in IRC+10216, and our observations represent the second astronomical detection of CO
ACTIVATION OF C-H BONDS: PURE ROTATIONAL SPECTROSCOPY OF HZnCH (\ {X} )
No full textAuthor Institution: Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721The pure rotational spectrum of HZnCH has been observed in its ground electronic state (\ {X} ) using both direct absorption and Fourier transform microwave techniques in the frequency range 18-516 GHz. Twelve rotational transitions of this symmetric top species were recorded in K-ladders up to K = 7. The molecule was synthesized from Zn(CH) in an AC discharge and also from Zn (vapor) + CH with a DC discharge. From measurements of the spectra of various isotopic species (Zn, Zn, Zn, C, and H), an accurate structure has been determined. The H-C-H bond angle was found to be , slightly smaller than that in ZnCH or CH. In addition, nuclear spin-rotation (I J) interactions with the methyl hydrogen nuclei and electric quadrupole coupling from the Zn nucleus were resolved in the FTMW spectrum. From these data, hyperfine parameters have been established. The value of eqQ = -109.125(11) MHz indicates that the bonds to zinc are primarily covalent. Detection of this species, especially via the Zn + CH pathway, is a good indication of the ability of metal atoms to insert into C-H bonds
