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2. Lanczos Approximations for the Speedup of Kernel Partial Least Squares Regression

Author

Kramer, N., Sugiyama, M., and Braun, M. L.

Subjects
FOS: Computer and information sciences, Statistics - Machine Learning, MathematicsofComputing_NUMERICALANALYSIS, Machine Learning (stat.ML)
Abstract

The runtime for Kernel Partial Least Squares (KPLS) to compute the fit is quadratic in the number of examples. However, the necessity of obtaining sensitivity measures as degrees of freedom for model selection or confidence intervals for more detailed analysis requires cubic runtime, and thus constitutes a computational bottleneck in real-world data analysis. We propose a novel algorithm for KPLS which not only computes (a) the fit, but also (b) its approximate degrees of freedom and (c) error bars in quadratic runtime. The algorithm exploits a close connection between Kernel PLS and the Lanczos algorithm for approximating the eigenvalues of symmetric matrices, and uses this approximation to compute the trace of powers of the kernel matrix in quadratic runtime., Comment: to appear in Proceedings of the 12th International Conference on Artificial Intelligence and Statistics (AISTATS 09)

Published
2009
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3. Scanning tunneling microscope induced oxidation of hydrogen passivated silicon surfaces

Author

Kramer, N., van den Berg, M.R., Schönenberger, C., and Physics of Interfaces and Nanomaterials

Subjects
Silicon, Scanning tunnelling microscopy (STM), Doping, Metals and Alloys, Analytical chemistry, Oxide, technology, industry, and agriculture, chemistry.chemical_element, Biasing, Surfaces and Interfaces, Substrate (electronics), Local oxidation nanolithography, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Threshold voltage, Nanostructures, chemistry.chemical_compound, chemistry, Oxidation, Materials Chemistry, IR-24141, METIS-128940, Quantum tunnelling
Abstract

We have investigated the mechanism of scanning tunnelling microscope (STM)-induced oxidation of a hydrogen passivated silicon surface in air. The influence of the relative air humidity, the Si doping concentration and the type and applied tip-sample voltage on the oxidation process was studied. The relative air humidity is crucial, if the relative air humidity drops below 10% no oxidation is observed. The width of the oxide lines increases with increasing tip-sample voltage. The voltage required to produce oxide lines on p-type Si is −1.1 V and does not depend on the doping concentration. For n-type Si, the threshold voltage for oxidation varies from −2.4 V for heavily doped to −3.5 V for lightly doped. A simple model is developed in which the electrical field between the tip (estimated as a sphere) and the substrate was calculated. We assume that a critical field is required to induce the oxidation. With this model, a good fit can be obtained with the experimentally found line-width dependence of the voltage. In addition, the effect of the doping type and concentration can be understood if depletion, in the case of n-type silicon, is included.

Published
1996
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4. Nanolithography on hydrogen terminateed silicon by scanning probe microscopy

Author

Schönenberger, Christian, Kramer, Niels, Kramer, N., and Physics of Interfaces and Nanomaterials

Subjects
Amorphous silicon, Materials science, Lithography, Silicon, STM, chemistry.chemical_element, IR-72936, Nanotechnology, Etch mask, Nanofabrication, chemistry.chemical_compound, Scanning probe microscopy, Electronic device, Etching (microfabrication), SFM, Device, Resist, Electrical and Electronic Engineering, Mask, Condensed Matter Physics, METIS-128939, Atomic and Molecular Physics, and Optics, Electron Beam Lithography, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Nanostructures, Scanning-probe microscope (SPM), Nanolithography, chemistry, Etching, Pattern transfer, Electron-beam lithography
Abstract

Scanning-probe microscopes (SPM), i.e. the scanning-tunneling and force microscopes, can be used to locally oxidize hydrogen-terminated silicon and hydrogenated amorphous silicon. Because of its reliability and potential for pattern transfer, this lithography process has found great attention and has become a prototype process for SPM nanolithography. The local oxidization can be performed in ambient or ultra-high vacuum (UHV), and it is initiated by strong electric fields, electron impact, or by short-wavelength light. In this article, the progress of this subfield of nanolithography is reviewed. Emphasis will be on the process conducted in humid environments were a fairly solid understanding is emerging. For completeness, important experiments performed in UHV will be discussed briefly. Finally, recent applications of this process technique to the fabrication of electronic devices will be presented.

Published
1996

5. Fabrication of metallic nanowires with a scanning tunnelling microscope

Author

Kramer, N., Birk, H., Jorritsma, J., Schönenberger, C., Physics of Interfaces and Nanomaterials, and Faculty of Science and Technology

Subjects
Amorphous silicon, Thin layers, Materials science, Physics and Astronomy (miscellaneous), business.industry, METIS-128898, Nanowire, Nanotechnology, Substrate (electronics), IR-72935, law.invention, chemistry.chemical_compound, chemistry, law, Etching, Optoelectronics, Thin film, Scanning tunneling microscope, Ion milling machine, business
Abstract

A procedure to pattern thin metal films on a nanometer scale with a scanning tunneling microscope (STM) operating in air is reported. A 30 nm film of hydrogenated amorphous silicon (a‐Si:H) is deposited on a 10 nm film of TaIr. Applying a negative voltage between the STM tip and the a‐Si:H film causes the local oxidation of a‐Si:H. The oxide which is formed is used as a mask to wet etch the not‐oxidized a‐Si:H and subsequently, the remaining pattern is transferred into the metal film by Ar ion milling. Metal wires as narrow as 40 nm have been fabricated. Since a‐Si:H can be deposited in very thin layers on almost any substrate, the presented procedure can be applied to structure all kind of thin films on a nanometer scale.

Published
1995

6. Resistless high reslotion optical lithography on Si

Author

Kramer, N., Niesten, M., Schönenberger, C., Physics of Interfaces and Nanomaterials, and Faculty of Science and Technology

Subjects
METIS-128897, IR-72932
Abstract

In this letter, we report on the high resolution patterning of a silicon surface without using a resist layer. A hydrogen passivated silicon surface is chemically modified by illumination with ultraviolet light (UV, λ=350.7 nm) in air. Auger electron spectroscopy (AES) revealed that silicon oxide was formed at the illuminated areas. A light interference pattern was made on the silicon surface by two UV laser beams, oxidation occurred only at the maximum intensity, but not at the minimum. In this way oxide lines were fabricated with a width below 200 nm on a 500 nm period. The oxide lines were used as a wet etch mask to etch more than 25 nm into Si(110) without affecting the oxide. The advantage of this technique is that it is a very simple process which allows the high resolution patterning over large areas of silicon without using a resist.

Published
1995

13. Infant Feeding

Author

Kramer, N.

Subjects
Correspondence, General Engineering, General Earth and Planetary Sciences, General Medicine, General Environmental Science
Published
1944
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14. Environmental and societal factors associated with COVID-19-related death in people with rheumatic disease: an observational study

Author

Zara Izadi, Milena A Gianfrancesco, Gabriela Schmajuk, Lindsay Jacobsohn, Patricia Katz, Stephanie Rush, Clairissa Ja, Tiffany Taylor, Kie Shidara, Maria I Danila, Katherine D Wysham, Anja Strangfeld, Elsa F Mateus, Kimme L Hyrich, Laure Gossec, Loreto Carmona, Saskia Lawson-Tovey, Lianne Kearsley-Fleet, Martin Schaefer, Samar Al-Emadi, Jeffrey A Sparks, Tiffany Y-T Hsu, Naomi J Patel, Leanna Wise, Emily Gilbert, Alí Duarte-García, Maria O Valenzuela-Almada, Manuel F Ugarte-Gil, Lotta Ljung, Carlo A Scirè, Greta Carrara, Eric Hachulla, Christophe Richez, Patrice Cacoub, Thierry Thomas, Maria J Santos, Miguel Bernardes, Rebecca Hasseli, Anne Regierer, Hendrik Schulze-Koops, Ulf Müller-Ladner, Guillermo Pons-Estel, Romina Tanten, Romina E Nieto, Cecilia N Pisoni, Yohana S Tissera, Ricardo Xavier, Claudia D Lopes Marques, Gecilmara C S Pileggi, Philip C Robinson, Pedro M Machado, Emily Sirotich, Jean W Liew, Jonathan S Hausmann, Paul Sufka, Rebecca Grainger, Suleman Bhana, Monique Gore-Massy, Zachary S Wallace, Jinoos Yazdany, Brahim Dahou, Gimena Gómez, Karen Roberts, Roberto M Baez, Vanessa V Castro Coello, María J Haye Salinas, Federico N Maldonado, Alvaro A Reyes, Gelsomina Alle, Hernán Maldonado Ficco, Romina Nieto, Carla Gobbi, Yohana Tissera, Cecilia Pisoni, Alba Paula, Juan A Albiero, Maria M Schmid, Micaela Cosatti, Maria J Gamba, Carlevaris Leandro, María A Cusa, Noelia German, Veronica Bellomio, Lorena Takashima, Mariana Pera, Karina Cogo, Maria S Gálvez Elkin, María A Medina, Veronica Savio, Romina Rojas Tessel, Rodolfo P Alamino, Marina L Werner, Sofía Ornella, Luciana Casalla, Maria de la Vega, María Severina, Mercedes García, Luciana Gonzalez Lucero, Cecilia Romeo, Sebastián Moyano, Tatiana Barbich, Ana Bertoli, Andrea Baños, Sandra Petruzzelli, Carla Matellan, Silvana Conti, Maria A Lazaro, Gustavo F Rodriguez Gil, Fabian Risueño, Maria I Quaglia, Julia Scafati, Natalia L Cuchiaro, Jonathan E Rebak, Susana I Pineda, María E Calvo, Eugenia Picco, Josefina G Yanzi, Pablo Maid, Debora Guaglianone, Julieta S Morbiducci, Sabrina Porta, Natalia Herscovich, José L Velasco Zamora, Boris Kisluk, Maria S Castaños Menescardi, Rosana Gallo, María V Martire, Carla Maldini, Cecilia Goizueta, Sabrina S de la Vega Fernandez, Carolina Aeschlimann, Gisela Subils, Eva Rath, Yves Piette, Mieke Devinck, Bea Maeyaert, Francinne Machado Ribeiro, Sandra L Euzebio Ribeiro, Marcelo Pinheiro, Sebastián Ibáñez, Anne-Marie Chassin Trubert, Lingli Dong, Lui Cajas, Marko Barešić, Branimir Anić, Melanie-Ivana Ćulo, Tea A Pavelić, Kristina K Stranski, Boris Karanovic, Jiri Vencovsky, Marta Píchová, Maria Filkova, Hesham Hamoud, Dimitrios Vassilopoulos, Gabriela M Guzman Melgar, Ho So, Márta Király, Mahdi Vojdanian, Alexandra Balbir Gurman, Fatemah Abutiban, Julija Zepa, Inita Bulina, Loreta Bukauskiene, Beatriz E Zazueta Montiel, Angel A Castillo Ortiz, Erick Zamora Tehozol, David Vega Morales, Diana Cervántes Rosete, Eduardo Martín Nares, Tatiana S Rodriguez Reyna, Marina Rull Gabayet, Deshiré Alpízar Rodríguez, Fedra Irazoque, Xochitl Jimenez, Lenny Geurts van Bon, Theo Zijlstra, Monique Hoekstra, Nasra Al Adhoubi, Babur Salim, Enrique Giraldo, Ariel Salinas, Manuel Ugarte Gil, Jarosław Nowakowski, Richard Conway, Rachael Flood, Geraldine McCarthy, Ioana Felea, Ileana Filipescu, Simona Rednic, Laura Groseanu, Maria M Tamas, Vanda Mlynarikova, Martina Skamlova, Martin Zlnay, Dagmar Mičeková, Lubica Capova, Zelmira Macejova, Emőke Šteňová, Helena Raffayova, Gabriela Belakova, Eva Strakova, Marieta Senčarová, Soňa Žlnayová, Anna Sabová, Daniela Spisakova, Mária Oetterová, Olga Lukacova, Martina Bakosova, Alojzija Hocevar, Natalia de la Torre Rubio, Juan J Alegre Sancho, Montserrat Corteguera Coro, Juan C Cobeta Garcia, Maria C Torres Martin, Jose Campos, Jose A Gomez Puerta, Gozd K Yardimci, Servet Akar, Ozan C Icacan, Selda ÇELİK, Viktoriia Vasylets, Su-Ann Yeoh, Claire Vandevelde, Sasha Dunt, Jane Leeder, Elizabeth Macphie, Rosaria Salerno, Christine Graver, Katie Williams, Sheila O'Reilly, Kirsty Devine, Jennifer Tyler, Elizabeth Warner, James Pilcher, Samir Patel, Elena Nikiphorou, Laura Chadwick, Caroline M Jones, Beverley Harrison, Lucy Thornton, Diana O'Kane, Lucia Fusi, Audrey Low, Sarah Horton, Shraddha Jatwani, Sara Baig, Hammad Bajwa, Vernon Berglund, Angela Dahle, Walter Dorman, Jody Hargrove, Maren Hilton, Nicholas Lebedoff, Susan Leonard, Jennifer Morgan, Emily Pfeifer, Archibald Skemp, Jeffrey Wilson, Anne Wolff, Eduardo Cepeda, Derrick Todd, Denise Hare, Cassandra Calabrese, Christopher Adams, Arezou Khosroshahi, Adam Kilian, Douglas White, Melanie Winter, Theodore Fields, Caroline Siegel, Nicole Daver, Melissa Harvey, Neil Kramer, Concetta Lamore, Suneya Hogarty, Karen Yeter, Faizah Siddique, Byung Ban, Tamar Tanner, Eric Ruderman, William Davis, Robert Quinet, Evangeline Scopelitis, Karen Toribio, Tameka Webb Detiege, Jerald Zakem, Khurram Abbass, Gilbert Kepecs, Lilliam Miranda, Michael Guma, Ammar Haikal, Sushama Mody, Daric Mueller, Arundathi Jayatilleke, JoAnn Zell, Alison Bays, Kathryn Dao, Fatemeh Ezzati, Deborah Parks, David Karp, Guillermo Quiceno, Izadi, Z, Gianfrancesco, M, Schmajuk, G, Jacobsohn, L, Katz, P, Rush, S, Ja, C, Taylor, T, Shidara, K, Danila, M, Wysham, K, Strangfeld, A, Mateus, E, Hyrich, K, Gossec, L, Carmona, L, Lawson-Tovey, S, Kearsley-Fleet, L, Schaefer, M, Al-Emadi, S, Sparks, J, Hsu, T, Patel, N, Wise, L, Gilbert, E, Duarte-Garcia, A, Valenzuela-Almada, M, Ugarte-Gil, M, Ljung, L, Scire, C, Carrara, G, Hachulla, E, Richez, C, Cacoub, P, Thomas, T, Santos, M, Bernardes, M, Hasseli, R, Regierer, A, Schulze-Koops, H, Muller-Ladner, U, Pons-Estel, G, Tanten, R, Nieto, R, Pisoni, C, Tissera, Y, Xavier, R, Lopes Marques, C, Pileggi, G, Robinson, P, Machado, P, Sirotich, E, Liew, J, Hausmann, J, Sufka, P, Grainger, R, Bhana, S, Gore-Massy, M, Wallace, Z, Yazdany, J, Dahou, B, Gomez, G, Roberts, K, Baez, R, Castro Coello, V, Haye Salinas, M, Maldonado, F, Reyes, A, Alle, G, Maldonado Ficco, H, Gobbi, C, Paula, A, Albiero, J, Schmid, M, Cosatti, M, Gamba, M, Leandro, C, Cusa, M, German, N, Bellomio, V, Takashima, L, Pera, M, Cogo, K, Galvez Elkin, M, Medina, M, Savio, V, Rojas Tessel, R, Alamino, R, Werner, M, Ornella, S, Casalla, L, de la Vega, M, Severina, M, Garcia, M, Gonzalez Lucero, L, Romeo, C, Moyano, S, Barbich, T, Bertoli, A, Banos, A, Petruzzelli, S, Matellan, C, Conti, S, Lazaro, M, Rodriguez Gil, G, Risueno, F, Quaglia, M, Scafati, J, Cuchiaro, N, Rebak, J, Pineda, S, Calvo, M, Picco, E, Yanzi, J, Maid, P, Guaglianone, D, Morbiducci, J, Porta, S, Herscovich, N, Velasco Zamora, J, Kisluk, B, Castanos Menescardi, M, Gallo, R, Martire, M, Maldini, C, Goizueta, C, de la Vega Fernandez, S, Aeschlimann, C, Subils, G, Rath, E, Piette, Y, Devinck, M, Maeyaert, B, Machado Ribeiro, F, Euzebio Ribeiro, S, Pinheiro, M, Ibanez, S, Chassin Trubert, A, Dong, L, Cajas, L, Baresic, M, Anic, B, Culo, M, Pavelic, T, Stranski, K, Karanovic, B, Vencovsky, J, Pichova, M, Filkova, M, Hamoud, H, Vassilopoulos, D, Guzman Melgar, G, So, H, Kiraly, M, Vojdanian, M, Balbir Gurman, A, Abutiban, F, Zepa, J, Bulina, I, Bukauskiene, L, Zazueta Montiel, B, Castillo Ortiz, A, Zamora Tehozol, E, Vega Morales, D, Cervantes Rosete, D, Martin Nares, E, Rodriguez Reyna, T, Rull Gabayet, M, Alpizar Rodriguez, D, Irazoque, F, Jimenez, X, Geurts van Bon, L, Zijlstra, T, Hoekstra, M, Al Adhoubi, N, Salim, B, Giraldo, E, Salinas, A, Ugarte Gil, M, Nowakowski, J, Conway, R, Flood, R, Mccarthy, G, Felea, I, Filipescu, I, Rednic, S, Groseanu, L, Tamas, M, Mlynarikova, V, Skamlova, M, Zlnay, M, Micekova, D, Capova, L, Macejova, Z, Stenova, E, Raffayova, H, Belakova, G, Strakova, E, Sencarova, M, Zlnayova, S, Sabova, A, Spisakova, D, Oetterova, M, Lukacova, O, Bakosova, M, Hocevar, A, de la Torre Rubio, N, Alegre Sancho, J, Corteguera Coro, M, Cobeta Garcia, J, Torres Martin, M, Campos, J, Gomez Puerta, J, Yardimci, G, Akar, S, Icacan, O, Celik, S, Vasylets, V, Yeoh, S, Vandevelde, C, Dunt, S, Leeder, J, Macphie, E, Salerno, R, Graver, C, Williams, K, O'Reilly, S, Devine, K, Tyler, J, Warner, E, Pilcher, J, Patel, S, Nikiphorou, E, Chadwick, L, Jones, C, Harrison, B, Thornton, L, O'Kane, D, Fusi, L, Low, A, Horton, S, Jatwani, S, Baig, S, Bajwa, H, Berglund, V, Dahle, A, Dorman, W, Hargrove, J, Hilton, M, Lebedoff, N, Leonard, S, Morgan, J, Pfeifer, E, Skemp, A, Wilson, J, Wolff, A, Cepeda, E, Todd, D, Hare, D, Calabrese, C, Adams, C, Khosroshahi, A, Kilian, A, White, D, Winter, M, Fields, T, Siegel, C, Daver, N, Harvey, M, Kramer, N, Lamore, C, Hogarty, S, Yeter, K, Siddique, F, Ban, B, Tanner, T, Ruderman, E, Davis, W, Quinet, R, Scopelitis, E, Toribio, K, Webb Detiege, T, Zakem, J, Abbass, K, Kepecs, G, Miranda, L, Guma, M, Haikal, A, Mody, S, Mueller, D, Jayatilleke, A, Zell, J, Bays, A, Dao, K, Ezzati, F, Parks, D, Karp, D, Quiceno, G, and Repositório da Universidade de Lisboa

Subjects
health care disparity, Immunology, air pollution, cohort analysi, mortality rate, Autoimmune Disease, Article, coronavirus disease 2019, biocontainment, Rheumatology, male, cardiovascular disease, environmental factor, death, geographic distribution, Immunology and Allergy, follow up, controlled study, human, population density, outcome assessment, rheumatic disease, diabetes mellitu, adult, Prevention, market, temperature, mortality, United Kingdom, Europe, aged, female, workplace, Good Health and Well Being, human development, particulate matter 2.5, statistical analysi, North America, incidence, life expectancy, social aspect, COVID-19 Global Rheumatology Alliance Registry, observational study, demographic
Abstract

Published by Elsevier Ltd., Background: Differences in the distribution of individual-level clinical risk factors across regions do not fully explain the observed global disparities in COVID-19 outcomes. We aimed to investigate the associations between environmental and societal factors and country-level variations in mortality attributed to COVID-19 among people with rheumatic disease globally. Methods: In this observational study, we derived individual-level data on adults (aged 18-99 years) with rheumatic disease and a confirmed status of their highest COVID-19 severity level from the COVID-19 Global Rheumatology Alliance (GRA) registry, collected between March 12, 2020, and Aug 27, 2021. Environmental and societal factors were obtained from publicly available sources. The primary endpoint was mortality attributed to COVID-19. We used a multivariable logistic regression to evaluate independent associations between environmental and societal factors and death, after controlling for individual-level risk factors. We used a series of nested mixed-effects models to establish whether environmental and societal factors sufficiently explained country-level variations in death. Findings: 14 044 patients from 23 countries were included in the analyses. 10 178 (72·5%) individuals were female and 3866 (27·5%) were male, with a mean age of 54·4 years (SD 15·6). Air pollution (odds ratio 1·10 per 10 μg/m3 [95% CI 1·01-1·17]; p=0·0105), proportion of the population aged 65 years or older (1·19 per 1% increase [1·10-1·30]; p, MAG is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers K01 AR070585 and K24 AR074534 [JY]). KDW is supported by the Department of Veterans Affairs and the Rheumatology Research Foundation Scientist Development award. JAS is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers K23 AR069688, R03 AR075886, L30 AR066953, P30 AR070253, and P30 AR072577), the Rheumatology Research Foundation (K Supplement Award and R Bridge Award), the Brigham Research Institute, and the R. Bruce and Joan M. Mickey Research Scholar Fund. NJP is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (T32-AR-007258). AD-G is supported by grants from the Centers for Disease Control and Prevention and the Rheumatology Research Foundation. RH was supported by the Justus-Liebig University Giessen Clinician Scientist Program in Biomedical Research to work on this registry. JY is supported by grants from the National Institutes of Health (K24 AR074534 and P30 AR070155).

Published
2022

15. Leucite-reinforced glass ceramic inlays luted with self-adhesive resin cement: a 2-year in vivo study

Author

Lorenzo Breschi, Roland Frankenberger, Norbert Krämer, Anselm Petschelt, Michael Taschner, Ulrich Lohbauer, Matthias Pelka, Taschner M, Kramer N, Lohbauer U, Pelka M, Breschi L, Petschelt A, Frankenberger R, Taschner, M, Krämer, N, Lohbauer, U, Pelka, M, Breschi, Lorenzo, Petschelt, A, and Frankenberger, R.

Subjects
Molar, Adult, Male, Ceramics, Materials science, Inlays and onlays, Surface Properties, Dentistry, Color, Ceramic, Inlay, Self-adhesive Resin cement, Clinical trials, Dental Materials, Young Adult, Materials Testing, dentin bonding systems, Humans, General Materials Science, Prospective Studies, Dental Enamel, General Dentistry, Cementation, Resin cement, Enamel paint, business.industry, Dental Marginal Adaptation, Middle Aged, Cementation (geology), Dental Porcelain, Resin Cements, Self adhesive, Treatment Outcome, Mechanics of Materials, Inlays, Patient Satisfaction, visual_art, visual_art.visual_art_medium, Aluminum Silicates, Female, business, Dental Cavity Preparation, Follow-Up Studies
Abstract

Objectives. Aim of the present prospective controlled clinical study was to compare the clinical performances of two different cementation procedures to lute IPS Empress inlays and onlays. Methods. Eighty-three IPS Empress restorations (70 class-II inlays, 13 onlays/47 premolars, 36 molars) were placed in 30 patients (19 females/11 males, mean age = 39 years). Two cementation procedures were tested: group 1: forty-three restorations were luted with a self-adhesive resin cement (RelyX Unicem, RX, 3M ESPE); group 2: forty restorations were luted with an etch-and-rinse multistep adhesive (Syntac Classic, Ivoclar-Vivadent) and Variolink II low (SV, Ivoclar-Vivadent). All restorations were evaluated after 2 weeks (baseline = 1st recall = R1, n = 83), 6 months (R2, n = 83), 1 year (R3, n = 82), and 2 years (R4, n = 82) by two independent blinded calibrated examiners using modified USPHS criteria. Results. From R1 to R4, one failure occurred in the SV group (at R2) due to marginal enamel chipping. After 2 years of clinical service (R4), better marginal and tooth integrity (p < 0.05) was found in group 2 (SV) compared to the use of the self-adhesive cement (RX, group 1), while no differences were found for all remaining investigated criteria (p > 0.05). The absence of enamel in proximal boxes (10% with no enamel and 51% of the restorations with less than 0.5 mm enamel width at the bottom of the proximal box) did not affect marginal performance (p > 0.05). Significance. The self-adhesive resin cement RelyX Unicem showed clinical outcomes similar to a conventional multi-step cementation procedure after 2 years of clinical service for most of the tested criteria. (C) 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Published
2011

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