Factors that influence the position of the peri-implant soft tissues: a review

Introduction: The implantological rehabilitation of the anterior sector is one of the most demanding and complex treatments due to the necessity of obtaining an optimum esthetic result. At the level of the soft tissues, it involves obtaining the complete formation of the papilla and creating a harmonic contour of the gingival margin.Objective: A bibliographical review has been carried out on the factors that influence the final position of the soft tissues.Material and methods: A search has been carried out in the Pubmed database of articles written in English and Spanish. Articles that presented a clinical series of less than five patients and a monitoring of less than one year were excluded.Results: At the level of the papilla, there are two decisive factors that play an influential role: the formation of the biological width and the distance between the alveolar crest and the contact point. The position of the gingival margin depends mainly of the height and width of the facial bone, as well as on the biotype. The surgical technique, as well as certain prosthodontics aspects related to the implant, can influence the final position of the soft tissues.Conclusions: Although, today we know much more about the factors that influence the position of the soft tissues, there are still certain aspects that should be studied more in-depth, for example the influence of the micro and macro-structure of the implant in the position of the soft tissues

The Stationary Phase Method for a Wave Packet in a Semiconductor Layered System. The applicability of the method

Using the formal analysis made by Bohm in his book, {\em "Quantum theory"}, Dover Publications Inc. New York (1979), to calculate approximately the phase time for a transmitted and the reflected wave packets through a potential barrier, we calculate the phase time for a semiconductor system formed by different mesoscopic layers. The transmitted and the reflected wave packets are analyzed and the applicability of this procedure, based on the stationary phase of a wave packet, is considered in different conditions. For the applicability of the stationary phase method an expression is obtained in the case of the transmitted wave depending only on the derivatives of the phase, up to third order. This condition indicates whether the parameters of the system allow to define the wave packet by its leading term. The case of a multiple barrier systems is shown as an illustration of the results. This formalism includes the use of the Transfer Matrix to describe the central stratum, whether it is formed by one layer (the single barrier case), or two barriers and an inner well (the DBRT system), but one can assume that this stratum can be comprise of any number or any kind of semiconductor layers.Comment: 15 pages, 4 figures although figure 4 has 5 graph

Variability of B and Be stars in the LMC/SMC: binaries and pulsations

To study the variability of the 523 B and Be stars observed in the Magellanic clouds with the VLT-FLAMES, we cross-matched the stars of our sample with the photometric database MACHO, which provides for each star an 8 years lightcurve. We searched for long, medium, and short-term periodicity and found the eclipsing binaries in our sample. For these stars, combining, spectroscopy and photometry, we were able to provide information on several systems of stars (systemic velocities, ratios of masses, etc). We also present the ratios of B-binaries to B-non binaries in the LMC/SMC in comparison with the MW. Note that this ratio is also an important issue to understand the mechanism of star-formation at low metallicity. We also found the first multiperiodic B and Be stars in the SMC, in particular the first SMC Beta Cep and SPB, while, according to the models, pulsations were not foreseen in low metallicity environments, i.e. typically in the SMC. Our results show that the instability strips are shifted towards higher temperatures in comparison with the Milky Way' strips of pulsating B-type stars. By the fact that we found more pulsating Be stars than pulsating B stars in the SMC, it seems that the fast rotation favours the presence of pulsations. However, the ratio of pulsating B-type stars to "non"-pulsating B-type stars at low metallicity is lower than at high metallicity.Comment: poster IAUS25

Estudio empírico sobre la influencia de recursos heurísticos en la resolución de problemas de probabilidad condicionada L0 y L2

Se ha constatado la dificultad de los estudiantes a la hora de resolver problemas de probabilidad condicionada (Cañadas et al., 2011). En general, la complejidad de estos problemas es debida a varios factores: el formato y el orden en el que se presentan los datos, el contexto en el que se plantea el problema, el lenguaje utilizado para expresar los datos condicionales o las herramientas utilizadas en el proceso de resolución. En nuestro estudio nos centraremos en el uso y la influencia de recursos heurísticos, como tablas de contingencia o diagramas de árbol, durante la resolución de un problema de probabilidad condicionada

Smile esthetic evaluation of mucogingival reconstructive surgery

To assess the difference in smile esthetic impact of Coronally Advanced Flap (CAF) with or without the adjunct of a collagen matrix (CMX) used as root coverage procedures. Subjects with esthetic demands showing multiple upper gingival recessions of at least 2 mm, without interproximal attachment loss and cervical abrasion no more than 1 mm were recruited and randomized to CAF plus CMX or CAF alone. The Smile Esthetic Index (SEI) was adopted to quantify the quality of the smile recorded at baseline and 12 months after treatment for each treatment group. In addition, between group difference in the SEI was calculated. 24 Patients were treated and analysed. At baseline, mean gingival recession depths were 2.3 ± 0.7 mm for Test group and 2.6 ± 1.0 mm for Control group. After 1 year, the residual recession depth was 0.3 ± 0.4 mm in the CAF + CMX group and 0.6 ± 0.3 mm in the control group. The SEI at baseline was 8.1 ± 1.0 and 7.9 ± 0.7 for Test and Control group, respectively. The between groups difference at 12 months in SEI was 0.4 (95% C.I. − 0.0 to 0.8, P = 0.0697). Twelve months after treatment, CAF + CMX provided a similar SEI compared to CAF alone and the adjunct of a collagen matrix did not show a different impact on the smile esthetic appearance

Natural or Palatal Positioning of Immediate Post-extraction Implants in the Aesthetic Zone? Five-year Outcomes of a Multicentre Randomised Controlled Trial

PURPOSE. To evaluate whether there is a difference in aesthetic outcomes when positioning immediate post-extractive implants in the “central” position (where the natural tooth would be in relation to adjacent teeth/implants) as opposed to roughly 3 mm more pala-tally. MATERIALS AND METHODS. Just after tooth extraction, 20 patients requiring one single immediate maxillary post-extraction implant, from second premolar to second premolar, were randomly allocated to receive one implant positioned in either the natural “central” position (central group; 10 patients), or about 3 mm more palatally (palatal group; 10 pa-tients) according to a parallel-group design at two different centres. When needed, sites were reconstructed, and bone-to-implant gaps were filled with granules of anorganic bovine bone and covered by resorbable collagen barriers. Implants were left submerged for 4 months and rehabilitated with provisional crowns, replaced after 4 months by definitive metal-ceramic crowns. Patients were followed up to 5 years after loading. Outcome measures were: crown and implant failures; complications; aesthetics, assessed using the pink aesthetic score (PES); peri-implant marginal bone level changes; and patient satisfaction, recorded by blinded assessors. RESULTS. Three patients from each group dropped out within 3 years after loading. Five years after loading, there were no significant differences between the two groups in median PES score, assessed by a blind assessor, (central: 10 [IQR: 5.5], palatal: 8.5 [IQR: 6.75], median difference =-1.0; 95% CI:-7.0 to 4.0; P = 0.571); median bone level (central: 0.45 mm [IQR: 1.76], palatal: 0.45 mm [IQR: 1.93], median difference = 0 mm; 95% CI:-1.7 to 3.0; P = 1.000); bone level changes (central: 0.15 mm [IQR: 0.70], palatal:-0.05 mm [IQR: 1.23], median difference =-0.20 mm; P = 0.471); implant failures (one in each group, 14%, difference in proportion = 0.00; 95% CI:-0.39 to 0.39; P = 1.000); or complications (two palatal group patients and one central group patient, difference in proportion = 0.14; 95% CI:-0.28 to 0.52; P = 1.000). Furthermore, patients from both groups were equally satisfied with both function and aesthetics (both P = 0.699). CONCLUSIONS. These preliminary results suggest that positioning of immediate post-ex-traction implants 3 mm more palatally may not, in fact, improve aesthetics; however, the sample size of the present study was very limited, and larger trials are therefore required to confirm or refute these findings

Dosimetric characterization of a brachytherapy applicator using MCNP5 modelisation and in-phantom measurements

[EN] A gynaecological applicator consisting of a metallic intra-uterine tube with a plastic vaginal applicator and an HDR Ir-192 source have been simulated with MCNP5 (Monte Carlo code). A solid phantom has been designed to perform measurements around the applicator with radiochromic films. The isodose curves obtained are compared with curves calculated with the F4MESH tally of MCNP5 with a good agreement. A pinpoint ionization chamber has been used to evaluate dose at some reference points. (c) 2009 Elsevier Ltd. All rights reserved.Gerardy, I.; Ródenas Diago, J.; Van Dycke, M.; Gallardo Bermell, S.; Ceccolini, E. (2010). Dosimetric characterization of a brachytherapy applicator using MCNP5 modelisation and in-phantom measurements. Applied Radiation and Isotopes. 68(4):735-737. doi:10.1016/j.apradiso.2009.10.018S73573768

Comorbidity between attention deficit hyperactivity disorder and reading disabilities: implications for assessment and treatment

Comorbidity of attention deficit hyperactivity disorder (ADHD) and reading disabilities (RD) is greater than what would occur by chance. Considering the well-documented adverse impact of both ADHD and RD on development, the presence of both conditions may lead to particularly poor outcomes for affected people. This chapter, which reviews 43 research studies carried out in the last decade that have focused on the link between ADHD and RD, is divided into two broad nuclei of contents. First, studies are described that contribute information about characteristics of the comorbid phenotype. Second, studies related to procedures directed toward evaluation and intervention in this problem are analyzed. The review carried out does not make it possible to extract definitive results on the exact nature of ADHD and RD comorbidity or, even less, reach conclusions about its causes. However, the literature-based evidence shows a cognitive profile of ADHD+RD characterized by failure of various functions that can produce more severe functional deficits and worse neuropsychological, academic, and behavioral outcomes. Furthermore, the analysis of the set of results from the studies shows a limited efficacy of pharmacological and psychopedagogical treatments, and highlights the need for continued research on this topic. From a clinical and educational standpoint, the conclusions derived from this review underline the importance of performing an exhaustive evaluation of children and adolescents with symptoms of ADHD and/or RD, in order to be able to plan interventions with greater possibilities of success in each cas