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Error in Figure In the original publication [1], there was a mistake in Figure 2 as published. “Aging” labels referring to “Yes” and “No” on the figure were switched. The corrected Figure 2 appears below. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.

To evaluate clinically the results of two surgical techniques used for root coverage, the coronally advanced flap in '' L '' isolated (CAF) or associated with subepithelial connective tissue graft (SCTG). The surgical procedures were performed in seventeen individuals, ten individuals in the control group (coronally advanced flap in "L") and seven individuals in the test group (coronally advanced flap in "L" associated with SCTG), who presented Miller class I and II gingival recession. The depth gingival recession (GR) index was evaluated in the following periods: immediate preoperative and 180 postoperative days. The control group had a success rate of 85 +/- 18 % and the test group had a success rate of 95 +/- 4 %. The variable success rates (p=0.36) did not present a statistically significant difference. The isolated CAF or its association with SCTG showed favorable outcomes in the treatments of Miller's class I and II gingival recessions. RESUMEN: El objetivo fue evaluar clínicamente los resultados de dos técnicas quirúrgicas utilizadas para la cobertura radicular, el colgajo coronalmente avanzado en "L" aislado (CAF) o asociado con injerto de tejido conectivo subepitelial (SCTG). Los procedimientos quirúrgicos se realizaron en diecisiete individuos, diez individuos en el grupo de control (colgajo coronario avanzado en "L") y siete individuos en el grupo de prueba (colgajo coronalmente avanzado en "L" asociado con SCTG), que presentaron la clase I de Miller y II recesión gingival. El índice de recesión gingival profunda (RG) se evaluó en los siguientes períodos: preoperatorio inmediato y 180 días postoperatorios. El grupo de control tuvo una tasa de éxito de 85 +/- 18 % y el grupo de prueba tuvo una tasa de éxito de 95 +/- 4 %. Las tasas de éxito variables (p = 0,36) no presentaron una diferencia estadísticamente significativa. La CAF aislada o su asociación con SCTG mostraron resultados favorables en los tratamientos de las recesiones gingivales de clase I y II de Miller.

Made available in DSpace on 2020-12-12T02:38:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-01 Purpose: The air-particle-abrasion on zirconia in the gingival area of connectors and pontics in fixed partial dentures appears to increase fracture resistance. This study evaluated 'in situ' biofilm formation on the zirconia surface after different air-particle-abrasion protocols. Materials and Methods: Ninety sintered blocks (5 x 5 x 2 mm) of yttrium partially stabilised zirconia (Y-TZP) were obtained and randomised among nine groups according to the factors 'type of particle' (Alumina 50 and 110 μm; Cojet and Rocatec) and 'pressure' (2.5 and 3.5 bar) used for sandblasting for 10 s. The surface roughness (Ra/ Rz) was measured before and after sandblasting. For the in-situ analyses, custom-made removable intraoral devices n = 10 with one sample of each group attached to the buccal area were used by volunteers for 8 h at night. The specimens were analysed under confocal microscopy to quantify both biovolume and thickness of the initial biofilm formed. One-way analysis of variance (ANOVA) and Dunnett's tests were performed (5%). Results: The roughness values ranged from 0.05 to 0.39 μm for Ra and from 0.35 to 2.11 μm for Rz, p = 0.00. Mean biofilm thickness ranged from 0.06 and 0.54 μm (p = 0.005), while the biovolume values were between 0.02 and 0.61 μm3/μm2 (p = 0.002). Values statistically significant for biofilm thickness and biovolume were found in groups sandblasted with Rocatec using 3.5 bar. Conclusion: In order to increase the fracture resistance of zirconia fixed partial dentures (FPDs), the air particle abrasion of zirconia with SiO2 (110 μm/3.5 bar), in the gingival area of connectors and pontics, should be avoided. Department of Dentistry Universidade de Braz Cubas Department Dental Materials and Prosthodontics São Paulo State University (Unesp) Institute of Science and Technology Department of Biotecnology UnP Laureate Universities Department of Dentistry Federal University of Rio Grande do Norte (UFRN) Department of Dentistry Prosthodontic Division Federal University of Rio Grande do Norte (UFRN) Department Dental Materials and Prosthodontics São Paulo State University (Unesp) Institute of Science and Technology

Dario Adolfi,1 João Paulo Mendes Tribst,1 Maurício Adolfi,2 Amanda Maria de Oliveira Dal Piva,1 Guilherme de Siqueira Ferreira Anzaloni Saavedra,1 Marco Antonio Bottino1 1Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, São José dos Campos, São Paulo, Brazil; 2Private Practice, São Paulo, BrazilCorrespondence: João Paulo Mendes Tribst Eng. Francisco José Longo, nº 777. Jardim São Dimas, São José dos Campos 12245-000, SP, BrazilTel +55 12 3947 9032Fax +55 12 3947 9010Email joao.tribst@gmail.comAbstract: The hybrid abutment emerged as an alternative to maintain a stable and favorable volume of peri-implant tissue; it is composed of a mesostructure in ceramic and a metallic connection, which can be machined according to the peri-implant emergence profile. This case report presented the clinical steps for a dental implant with immediate provisional restoration, followed by the installation of implant-supported all-ceramic crowns with zirconia abutment and platform switching. A 40-year-old male patient was rehabilitated with an implant-supported ceramic crown in the region of element 11 and a ceramic veneer was cemented on the upper right central incisor. To do so, an atraumatic extraction of the upper left central incisor was performed followed by implant placement and immediate loading. In this case, a zirconia hybrid abutment was used with a metallic link in the cervical region with a concave platform switching base. This association of clinical steps enabled improving the aesthetics in the anterior dental region.Keywords: dental implants, soft tissue, esthetic, adhesive

Made available in DSpace on 2020-12-10T19:47:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-02-01 Objectives. This study aimed to evaluate the effect of different materials and undercut on the removal force and stress distribution in the supporting tooth and in the circumferential clasp used in removable partial prosthesis. Methods. Upper molars prepared for Akers circumferential clasp with retention and opposing arm were modeled, scanned, elaborated with CAD software and the geometries imported in FEA and analyzed. Six different materials were selected for the clasp (Polyamide, Poly-oxymethylene, Polyetheretherketone - PEEK, Gold alloy, Titanium and CoCr) and 3 different undercuts (0.25, 0.50 and 0.75 mm), totaling 18 groups. Results. The clasps presented greater stress in their structure and potentially greater damage to the dental enamel when made with rigid materials and with more undercut; however, they presented greater ability to remain in position. Significance. Polyamide with a higher undercut is an esthetic alternative to rigid metallic clasps. It showed promising behavior because it strongly reduces the damage to the enamel, and even with an undercut of 0.75, the retention is lower than for CoCr with a 0.25 undercut, and this retention might still be sufficient. Polyoxymethylene and Polyetheretherketone (PEEK) are not suitable materials for the clasps, because the maximum stress occurring during removal with higher undercuts is higher than the material strength. (C) 2019 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved. Sao Paulo State Univ Unesp, Inst Sci & Technol, PhD Grad Program Restorat Dent, Av Engn Francisco Jose Longo 777, BR-12245000 Sao Jose Dos Campos, SP, Brazil Univ Amsterdam, Acad Ctr Dent Amsterdam ACTA, Dept Dent Mat Sci, Gustav Mahlerlaan 3004, NL-1081 LA Amsterdam, Noord Holland, Netherlands Vrije Univ, Gustav Mahlerlaan 3004, NL-1081 LA Amsterdam, Noord Holland, Netherlands Sao Paulo State Univ Unesp, Inst Sci & Technol, PhD Grad Program Restorat Dent, Av Engn Francisco Jose Longo 777, BR-12245000 Sao Jose Dos Campos, SP, Brazil

Made available in DSpace on 2021-06-25T11:05:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Purpose: To evaluate the effect of composite resin polymerization shrinkage stress on the stress distribution in the implant-supported crown-access hole, and on the bond strength between the ceramic and composite resin. Materials and Methods: A 3D model of a ceramic crown, in which the access hole was filled with composite resin (conventional or bulk-fill), was used to evaluate the stress distribution in the access hole using finite element analysis. The contacts were considered bonded and the polymerization shrinkage was simulated based on the coefficient of linear thermal expansion of each resin. The push-out test (1 mm/min, 100 kgf) was performed on perforated lithium disilicate samples filled with conventional or bulk-fill resins to validate the stress data of the bond strength. One-way ANOVA and Tukey's test were used to analyze the bond strength data, with α set at 5%. Results: Conventional resin showed the worst stress distribution and highest displacement values, von Mises stress, maximum principal strain, maximum principal stress, and maximum shear stress vs the bulk-fill resin. Statistically significantly greater bond strength was observed for bulk-fill (13.40 ± 5.59 MPa) than the conventional resin (8.70 ± 3.02 MPa). Conclusion: Comparing both materials tested in the present study, the use of bulk-fill composite resin to seal the screw-access hole is suggested to reduce the stress concentration and increase bond strength to the ceramic crown. Dentist Department of Dental Materials and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology Adjunct Professor Department of Dental Material and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology Professor Department of Dental Material and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology Professor Department of Dental Materials Science Academic Centre for Dentistry Amsterdam (ACTA) Universiteit van Amsterdam and Vrije Universiteit Dentist Department of Dental Materials and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology Adjunct Professor Department of Dental Material and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology Professor Department of Dental Material and Prosthodontics São Paulo State University (UNESP) Institute of Science and Technology

Made available in DSpace on 2020-12-12T02:41:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-05-01 Purpose: To evaluate the effect of surface conditioning methods and aging on the repair bond strength between resin composite and nanoceramic CAD/CAM resin. Materials and Methods: Twenty-four blocks of nanoceramic CAD/CAM resin (NCR) (Lava Ultimate, 3M Oral Care) (10 x 5 x 2 mm3) and resin composite (Filtek Z350, 3M Oral Care) (RC) were made, embedded in acrylic resin, polished (#600, #800, #1200) and randomly divided into 8 groups (n = 12 each) according to surface conditioning methods (air abrasion with 30-μm CoJet [CJ] or air abrasion with 50-μm Al2O3 [AB]) and aging prior to repair (without aging, 24 h in water at 37°C; with aging 6 months in water at 37°C). The blocks were air abraded (20 s, 2.5 bar, 10 mm) using a standardized device. A layer of adhesive resin (Scotchbond Universal) was applied (20 s) and photopolymerized for 20 s. RC cylinders (O = 2 mm; h = 2 mm) were then bonded to the NCR substrates using a Teflon matrix and photopolymerized for 40 s. All specimens were thermocycled (10,000 cycles, 5°C-55°C) and submitted to the shear bond test (50 kgf, 0.5 mm/min) to measure repair strength. Data (MPa) were analyzed using 3-way ANOVA and Tukey's test (α = 0.05). Failure analysis was performed using stereomicroscopy (20X). Results: ANOVA revealed a significant effect of only the material factor (p = 0.00). The group NCR6mCJ presented bond strengths (29.37 ± 5.41) which were significantly higher than those of the NCR24hCJ (20.88 ± 5.74) and RC groups (p < 0.05). The group RC24hCJ (19.71 ± 4.21) presented the lowest shear bond strength (p < 0.05). Failure analysis revealed predominantly type B mixed failures (adhesive+cohesive in the substrate material) except for the groups NCR24hCJ and NCR6mAB, where mainly type C failure (adhesive+cohesive at the RC) was observed. Conclusion: Air abrasion with Al2O3 particles or silicatization with CoJet followed by adhesive resin application are effective surface conditioning methods for the repair of nanoceramic CAD/CAM resin with resin composite. Federal University of Rio Grande do Norte (UFRN) Department of Dentistry São Paulo State University (UNESP) Private Practice São Paulo State University (UNESP) Institute of Science and Technology, São José dos Campos University of Zurich Center for Dental and Oral Medicine Dental Materials Unit Clinic for Fixed and Removable Prosthodontics and Dental Materials Science São Paulo State University (UNESP) São Paulo State University (UNESP) Institute of Science and Technology, São José dos Campos

RESUMEN: El objetivo de este trabajo consistió en evaluar la resistencia al cizallamiento de brackets ortodónticos cementados a una cerámica odontológica a base de disilicato de litio. Fueron confeccionadas 80 muestras rectangulares de cerámica vítrea a base de disilicato de litio. Las muestras fueron divididas inicialmente en 4 grupos de 20 discos según el tratamiento de superficie: ácido fosfórico 37 % por 30 segundos (HP); ácido hidrofluorhidro 10 % por 60 segundos (HF); óxido de aluminio durante 4 segundos (SB); y aspersión con punta diamantada durante 10 segundos (DW). Cada grupo fue dividido en dos subgrupos para la cementación de brackets Edgwise: metálico y cerámico. Los dos nuevos grupos fueron subdivididos en termociclados o no termociclados. Las muestras termocicladas pasaron por 500 ciclos con variaciones de temperatura entre 5 °C a 55 °C. Los valores numéricos obtenidos en la prueba de cizallamiento se sometieron al análisis estadístico descriptivo (media y desviación estándar), habiéndose realizado la prueba de normalidad Shapiro-Wilk y las pruebas no paramétricas de Kruskal-Wallis y Mann-Whitney. Se verificó que no hubo diferencia estadísticamente significativa en relación al tipo de tratamiento de superficie y la realización o no de termociclado, observándose diferencia estadísticamente significativa sólo en el tipo de bracket, siendo la resistencia de unión en el bracket metálico mayor que en el de cerámica. Así, el tipo de tratamiento de superficie y el envejecimiento por termociclaje no fueron decisivos en la resistencia de unión de brackets ortodónticos a la cerámica de disilicato de litio. ABSTRACT: To evaluate the shear strength of cemented orthodontic brackets to a dental ceramic based on lithium disilicate. Rectangular samples 80 based glassceramic lithium disilicate were prepared. The samples were initially divided into 4 groups of 20 discs according to surface treatment: 37 % phosphoric acid for 30 seconds (HP); 10 % hydrofluoric acid for 60 seconds (HF); blasting with aluminum oxide for 4 seconds (SB); and diamond-tipped for 10 seconds (DW). Each group was divided into two subgroups for the Edgwise bracket cementation: metallic and ceramic. The two new groups were subdivided into thermocyclers or nonthermocyclics. The thermocycled samples passed 500 cycles with temperature variations between 5 ° C to 55 ° C. The numerical values obtained in the shear test were submitted to descriptive statistical analysis (mean and standard deviation), and the Shapiro-Wilk normality test and nonparametric Kruskal-Wallis and Mann-Whitney tests were performed. It was found that there was no statistically significant difference in the type of surface treatment and conducting or not thermocycling, observing statistically significant difference only on the bracket type, and the bond strength at higher metal bracket than in ceramics. Thus, the type of surface treatment and thermocycling aging were not decisive in the bond strength of orthodontic brackets to the lithium disilicate ceramic.