Is scanning under rubber dam isolation a feasible approach for the execution of indirect restorations? / O escaneamento sob isolamento absoluto é uma técnica viável para execução de restaurações indiretas?

Objective: The aim of the study was to report the aplicability of intraoral scanning while rubber dam isolation is in place. Material and Methods: Female patient, 50 years old, required restorative procedures on teeth 35 and 37. An intraoral scan was initially performed on both arches. Isolation was carried out from 33 to 37, tooth preparation and immediate dentin sealing were carried out. A new scan with the rubber dam in place was performed and a CAD/CAM lithium disilicate hybrid block was digitally designed, milled, crystallized and cemented under the tooth surface with the rubber dam still in position. After completing this stage, the rubber dam was removed, the occlusion was verified, presenting excellent aesthetic and functional results. Results: The absolute isolation process used in the present study works as an excellent device for gingival retraction. Conclusion: The absolute isolation can be recommended in clinical activities of intraoral scanning favoring the quality of the final result of treatments (AU)

Objetivo: O objetivo do estudo foi relatar a aplicabilidade do escaneamento intraoral sob isolamento absoluto. Material e Métodos: Paciente do sexo feminino, 50 anos, necessitou de procedimentos restauradores nos dentes 35 e 37. Uma varredura intraoral foi inicialmente realizada em ambos os arcos. O isolamento absoluto foi feito de 33 a 37, permitindo a realização do preparo dentário e selamento imediato da dentina. Um novo escaneamento com o dique de borracha colocado foi realizado e um bloco híbrido de dissilicato de lítio CAD/CAM foi projetado digitalmente, fresado, cristalizado e cimentado sob a superfície dentária ainda com o dique de borracha em posição. Após a finalização dessa etapa, o dique de borracha foi removido, a oclusão foi verificada apresentando ótimos resultados estéticos e funcionais. Resultados: O isolamento absoluto utilizado no presente estudo funciona como um excelente dispositivo para retração gengival. Conclusão: O isolamento absoluto pode ser recomendado em atividades clínicas de escaneamento intraoral favorecendo a qualidade do resultado final dos tratamentos (AU)

Assessment of Subgingival Biofilm and its Relationship with the Status of Tumors in a Population with Breast Cancer

This study aimed to compare the subgingival microbiota of subjects with and without breast cancer (BC). Patients with BC (Group 1; n= 50) and without BC (Group 2; n=50) with periodontitis (A) and without periodontitis (B). The study was conducted in two phases (P1 and P2). One biofilm sample was collected from each subject and analyzed by DNA-DNA Hybridization (Checkerboard DNA-DNA). The relative abundance of the subgingival microbiota differed between the Case and Control groups. However, some species were higher in patients in the Case than in Control subjects and differed between the groups in both phases. Composition of the subgingival microbial community according to the Socransky complex was related to periodontal disease, followed by clinical attachment of level (CAL ≥4mm), age, and tooth loss, which were found to be abundant in Cases when compared with controls. Patients with Tumor Grade II and III had a higher prevalence of tooth loss and CAL≥4mm. It was concluded that in individuals with BC, the sub-gingival microbiota exhibited atypical changes, but they developed periodontal disease.

El objetivo de este estudio fue comparar la microbiota subgingival de sujetos con y sin cáncer de mama (CM). Pacientes con CM (Grupo 1; n= 50) y sin CM (Grupo 2; n=50) con periodontitis (A) y sin periodontitis (B). El estudio se realizó en das fases (P1 y P2). Se recogió una muestra de biopelícula de cada sujeto y se analizó mediante hibridación ADN-ADN (tablero de ajedrez ADN-ADN). La abundancia relativa de la microbiota subgingival difirió entre los grupos de Caso y Control. Sin embargo, algunas especies fueron más altas en los pacientes del Caso que en los sujetos del Control y difirieron entre los grupos en ambas fases. La composición de la comunidad microbiana subgingival según el complejo de Socransky se relacionó con la enfermedad periodontal, seguida por el nivel de inserción clínica (CAL≥4mm), la edad y la pérdida de dientes, que se mostró abundante en los casos en comparación con los controles. Los pacientes con Tumor Grado II y III tuvieron mayor prevalencia de pérdida dental y CAL≥4mm. Se concluyó que en individuos con CM la microbiota subgingival presentó cambios atípicos, pero sin embargo, desarrollaron enfermedad periodontal.

Injectable Composite Resin Technique: An Alternative for Anterior Esthetic Restorations - Case Report / Técnica de Resina Compuesta Inyectable: Una Alternativa para Restauraciones Estéticas Anteriores - Reporte de Caso

This article aims to describe a clinical case of the use of the injectable restorative technique with composite resin in a patient with an esthetic complaint in the anterior teeth. Producing direct restorations in anterior teeth when performed with composite resin demands a long clinical time. Results often depend on the operator's ability to reproduce proper form, function, and esthetics. Lately, the versatility of composite resins has increased. As this material evolved, new techniques were introduced to simplify the restorative process and save time. The restorative technique with injectable fluid composite resin, in addition to delivering faster and with a certain ease, is capable of increasing the predictability of treatment results. However, it is known that flowable resins have lower wear resistance and color stability compared to conventional resins. Thus, a version of this material with a higher filler content in its composition was introduced to the market, to improve wear resistance and gloss retention. Long-term studies evaluating the use of low-viscosity resins are needed. The injectable technique can accurately reproduce the morphology obtained in the wax-up of the case, generating a satisfactory esthetic and functional result. Despite simplifying the fabrication of restorations when compared to the conventional technique, it is still necessary for the operator to have some experience and aptitude. The clinical time for the production of restorations has been considerably reduced. The material showed good flow, shine, and polish in the immediate result. However, the finishing and polishing of the restorations required a longer clinical period than usual and in the short- term follow-up, flaws in the gingival margins and a new finishing and polishing procedure were necessary. Therefore, the technique described in this article can be considered a restorative alternative, but it is still not able to replace the tradit ional method of making previous esthetic restorations.

Este artículo tiene como objetivo describir un caso clínico del uso de la técnica restauradora inyectable con resina compuesta en un paciente con una queja estética en los dientes anteriores. Producir restauraciones directas en dientes anteriores cuando se realizan con resina compuesta demanda un largo tiempo clínico. Los resultados a menudo dependen de la capacidad del operador para reproducir la forma, la función y la estética adecuadas. Últimamente, la versatilidad de las resinas compuestas ha aumentado. A medida que este material evolucionó, se introdujeron nuevas técnicas para simplificar el proceso de restauración y ahorrar tiempo. La técnica restauradora con resina compuesta fluida inyectable, además de una entrega más rápida y segura, es capaz de aumentar la previsibilidad de los resultados del tratamiento. Sin embargo, se sabe que las resinas fluidas tienen menor resistencia al desgaste y estabilidad del color en comparación con las resinas convencionales. Así, se introdujo en el mercado una versión de este material con un mayor contenido de relleno en su composición, con el objetivo de mejorar la resistencia al desgaste y la retención del brillo. Se necesitan estudios a largo plazo que evalúen el uso de resinas de baja viscosidad. La técnica inyectable es capaz de reproducir fielmente la morfología obtenida en el encerado del caso, generando un resultado estético y funcional satisfactorio. A pesar de simplificar la fabricación de restauraciones en comparación con la técnica convencional, todavía es necesario que el operador tenga cierta experiencia y aptitud. El tiempo clínico para la producción de restauraciones se ha reducido considerablemente. El material mostró buena fluidez, brillo y pulido en el resultado inmediato. Sin embargo, el acabado y pulido de las restauraciones requirió de un período de tiempo clínico más largo de lo habitual y en el seguimiento a corto plazo, fueron necesarios defectos en los márgenes gingivales y un nuevo procedimiento de acabado y pulido. Por lo tanto, la técnica descrita en este artículo puede considerarse una alternativa restauradora, pero aún no es capaz de reemplazar el método tradicional de realizar restauraciones estéticas previas.

Current Insights on Neoplasms and Adequate Dental Care for Patients with Oral Cancer / Actualización sobre Neoplasmas y su Correcta Atención Odontológica en Pacientes con Cancer Oral

The present study aimed to review the literature on the main complications of antineoplastic therapies and the degree of knowledge of dental surgeons about these complications. A bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 1987 to 2023 were collected. Laboratory studies, case reports, systematic and literature reviews, which were developed in living individuals, about the main neoplastic genes and their relationship with the cells of individuals affected by neoplasms in the head and neck region, and studies on the care with this group of patients, were included. Therefore, articles that did not deal with neoplasm and the main complications of antineoplastic therapies were excluded. Neoplasm is a clonal disorder, caused by mutations, resulting from changes in the genetic structure of cells. Each healthy cell has instructions on how to grow and divi de. In the presence of any error in these instructions (mutation), it can result in a diseased cell that, when proliferating, may cause a tumor. Countless knowledge has been accumulated over the years on the main characteristics of neoplasms, whether they are cancer cell biology, carcinogenesis mechanism, neoplasms of the maxillofacial system and sequels of antineoplastic treatments. In this context, methods have been developed that offer a better quality of life for patients diagnosed with this pathology, as well as preventive vaccine models that may, in the not too distant future, contribute to this goal to be successfully achieved.

El presente estudio tuvo como objetivo revisar la literatura sobre las principales complicaciones de las terapias antineoplásicas y el grado de conocimiento de los odontólogos sobre este abordaje. Se realizó una búsqueda bibliográfica en las principales bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en la que se recopilaron estudios publicados entre 1987 y 2023. Fueron incluidos estudios de laboratorio, relatos de casos, revisiones de la literatura y revisiones sistemáticas, desarrolladas en individuos vivos, que incluyeran los principales genes neoplásicos y su relación con las células de individuos afectados por neoplasias en la cabeza y el cuello. También, se tuvieron en cuenta estudios relacionados con la atención a este grupo de pacientes. La neoplasia es un trastorno clonal, causado por mutaciones, como resultado de cambios en la estructura genética de las células. Cada célula sana tiene instrucciones sobre cómo crecer y dividirse. En presencia de cualquier error en estas instrucciones (mutación), puede provocar una célula alterada que, al proliferar, puede causar un tumor. Se han acumulado innumerables conocimientos a lo largo de los años sobre las principales características de las neoplasias, ya sea sobre biología de células cancerosas, el mecanismo de la carcinogénesis, la neoplasias del sistema maxilofacial y las diferentes secuelas de tratamientos antineoplásicos. En este contexto, se han desarrollado métodos que ofrecen una mejor calidad de vida para los pacientes diagnosticados con esta patología, así como modelos de vacunas preventivas que, en un futuro no muy lejano, pueden contribuir a alcanzar este objetivo con éxito.

Biomechanical Behavior Evaluation of a Mandibular Full-Arch Implant-Supported Prosthesis on ZrO2 and TiO2 Monotype Dental Implants / Evaluación del Comportamiento Biomecánico de una Prótesis Implante Soportada de Arcada Completa Mandibular sobre Implantes Dentales Monotipos de ZrO 2 y TiO

This in silico study aimed to evaluate the biomechanical behavior of a full-arch implant-supported prosthesis on titanium and zirconia monotype implants. A 3D mandible containing 1.0 mm thick cortical and cancellous bone was modeled. Four dental implants (3.3 x 10 mm) were inserted into the jaw model in each model. The implants consisted of Titanium (Ti-S group) and Zirconia Monotype/one-piece (Zr-S group). Fixed full-arch implant-supported prostheses were cemented onto the implant. The models were exported to the analysis software and divided into meshes composed of nodes and tetrahedral elements. All materials were considered isotropic, elastic, and homogeneous. Therefore, all contacts were considered bonded, the mandible model was fixed in all directions, applying a static structural axial load of 300 N on the bottom of the fossa of the left mola r teeth. Microstrain and von-Mises stress (MPa) were adopted as failure criteria. Comparable stress and strain values were shown in the peri-implant bone for both groups. However, the Ti-S group presented a lower stress value (1,155.8 MPa) than the Zr-S group (1,334.2 MPa). Regarding bone tissues, the Ti-S group presented 612 µε and the Zr-S group presented 254 µε. The highest strain peak was observed in bone tissues around the implant closer to the load for both groups. Evaluating monotype zirconia and titanium implants, it is suggested that the greater the rigidity of the implant, the greater the concentration of internal stre sses and the less dissipation to the surrounding tissues. Therefore, monotype ceramic implants composed of yttrium-stabilized tetragonal polycrystalline zirconia may be a viable alternative to titanium implants for full-arch prostheses.

El objetivo de este estudio in silico fue evaluar el comportamiento biomecánico de una prótesis implanto soportada de arcada completa sobre implantes monotipo de titanio y zirconia. Se modeló una mandíbula en 3D que contenía tejido óseo cortical y esponjoso de 1,0 mm de espesor. En cada modelo, se insertaron cuatro implantes dentales (3,3 x 10 mm) en el modelo de mandíbula. Los implantes consistieron en Monotipo de Titanio y Zirconia. Sobre el implante se cementaron prótesis implanto soportadas de arcada completa fija. Los modelos se exportaron al software de análisis y se dividieron en mallas compuestas por nodos y elementos tetraédricos. Todos los materiales se consideraron isotrópicos, elásticos y homogéneos. Por lo tanto, todos los contactos se consideraron cementados, el modelo mandibular se fijó en todas las direcciones, aplicando una carga vertical estructural estática de 300 N en el fondo de la fosa de los dientes molares izquierdos. Se seleccionaron la microesfuerzo y la tensión de Von-Mises (MPa) como criterios de falla. Se mostraron valores de tensión y deformación comparables en el hueso periimplantario para ambos grupos. Sin embargo, el grupo Ti-S presentó un valor de estrés menor (1.155,8 MPa) que el grupo Zr-S (1.334,2 MPa). En cuanto a los tejidos óseos, el grupo Ti-S presentó 612 µε y el grupo Zr-S presentó 254 µε. La mayor concentración de deformación en el tejido óseo se observó en los tejidos alrededor del implante más cerca de la carga para ambos grupos. Al evaluar los implantes monotípicos de zirconia y titanio, se sugiere que cuanto mayor sea la rigidez del implante, mayor será la concentración de tensiones internas y menor la disipación a los tejidos circundantes. Por lo tanto, los implantes cerámicos monotipo compuestos de zirconia policristalina tetragonal estabilizada con itrio pueden ser una alternativa viable a los implantes de titanio para prótesis de arcada completa.

Knowledge, Attitudes, and Practices on New Treatment Modalities for Temporomandibular Dysfunctions and Orofacial Pain / Conocimientos, Actitudes y Prácticas sobre Nuevas Nodalidades de Tratamiento de las Disfunciones Tempomanibulares y el Dolor Orofacial

The present study proposed to describe, through a literature review, the use of new therapeutic management which allows for offering a better quality of life to individuals affected by these pathologies. A bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 1987 to 2023 were collected. In the first stage, the list of retrieved articles was examined by reading the titles and abstracts. In the second stage, the studies were selected by reading the full contents. Two authors (JDMM and DAQ) performed stages 1 and 2. Experimental, clinical, case-control, randomized controlled, and laboratory cohort studies, case reports, systematic reviews, and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the subject in question, letters to the editor, opinion articles, duplicated literature in databases, and literature that did not address the variables under study, we re excluded. Contemporary dentistry uses alternative treatments capable of improving the patient's condition since a cure is not always possible. Therefore, the possibility of improving the quality of life becomes an important point to be reached. Evidence-based healthcare has made great advances in recent decades, especially in the areas of orofacial pain, TMD, and occlusion, especially related to orthodontic, prosthetic, and restorative care.

En el presente estudio se propuso describir, a través de una revisión bibliográfica, el uso de nuevos manejos terapéuticos que permitan brindar una mejor calidad de vida a los individuos afectados por estas patologías. Se realizó una búsqueda bibliográfica en las principales bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en las que se recopilaron estudios publicados entre 1987 y 2023. En la primera etapa, se examinó la lista de artículos recuperados mediante la lectura de los títulos y resúmenes. En la segunda etapa, los estudios fueron seleccionados mediante la lectura del contenido completo. Dos autores (JDMM y DAQ) realizaron las etapas 1 y 2. Se incluyeron estudios de cohortes experimentales, clínicos, de casos y controles, controlados aleatorios y de laboratorio, informes de casos, revisiones sistemáticas y revisiones de la literatura, que se desarrollaron en individuos vivos. Por lo tanto, se excluyeron artículos que no trataran el tema en cuestión, cartas al editor, artículos de opinión, literatura duplicada en bases de datos y literatura que no abordara las variables en estudio. La odontología contemporánea utiliza tratamientos alternativos capaces de mejorar el estado del paciente, ya que no siempre es posible la curación. Por lo tanto, la posibilidad de mejorar la calidad de vida se convierte en un objetivo importante. La atención médica basada en la evidencia ha logrado grandes avances en las últimas décadas, especialmente en las áreas de dolor orofacial, TMD y oclusión, especialmente en relación con la atención de ortodoncia, prótesis y restauración.

Dental and Periodontal Conditions in Alcoholics from a Brazilian Recovery Centera

ABSTRACT: The aim of this study was to evaluate the dental and periodontal condition of alcohol-dependents from a Brazilian Recovery Center. Sixty male individuals (30 alcoholic and 30 non-alcoholic) and aged between 32 and 72 years old were clinically evaluated. Interviews, dental and periodontal clinical examinations were obtained from all participants. The Pearson Chi-Square Test and Exact Fisher test were used to compare categorical data. The t-Student's test was adopted for non-categorical data. Multiple logistic regressions were used to evaluate the association of variables in the groups. The alcoholics were younger, consumed more tobacco, had lower frequency of tooth brushing and dental flossing, higher number of missing and decayed teeth, more residual root, and more teeth with presence of visible plaque index (OR = 0.5, 95 % Cl = 4.4 to 5.5), when compared to the non-alcoholics. Alcoholics at the Recovery Center performed poor oral hygiene, had higher number of sites with periodontal disease, and worse oral hygiene than non-alcoholic individuals. As regards professional follow-up, there was similarity between the groups evaluated.

RESUMEN: El objetivo de este estudio fue evaluar las condiciones dentales y periodontales de los alcohólicos de un Centro de Recuperación de Brasil. Sesenta hombres (30 alcohólicos y 30 no alcohólicos) y con edades comprendidas entre 32 y 72 años fueron evaluados clínicamente. Se obtuvieron entrevistas, exámenes clínicos dentales y periodontales de todos los participantes. La prueba de Chi-cuadrado de Pearson y la prueba exacta de Fisher se utilizaron para comparar datos categóricos. La prueba de t-Student se adoptó para datos no categóricos. Se utilizaron regresiones logísticas múltiples para evaluar la asociación de variables en los grupos. Los alcohólicos eran más jóvenes, consumían más tabaco, tenían menor frecuencia de cepillado dental y uso de hilo dental, mayor número de dientes perdidos y cariados, más raíz residual y más dientes con presencia de índice de placa visible (OR = 0,5, 95 % Cl = 4,4 a 5,5), en comparación con los no alcohólicos. Los alcohólicos en el Centro de Recuperación realizan una mala higiene bucal, tenían un mayor número de sitios con enfermedad periodontal y una peor higiene bucal que los no alcohólicos. En cuanto al seguimiento profesional, hubo similitud entre los grupos evaluados.

Survival Analysis and Torque Loosening of Experimental Screw After Mechanical Performance for Micro Conical Abutment

ABSTRACT: The most common failure in implantology are due to mechanical instability. Torque loosening or fracture of the screws are the most frequent complications. Furthermore, the fractured screw retrieval is complicated and time-consuming. So, modifications in the design of implant systems are justifiable to offer a greater degree of biomechanical stability. Thus, the present study proposes to evaluate an experimental geometry for abutment screw regarding failure probability and torque loss. Twenty implant/abutments sets (e-fix, A.S. Technology - Titanium Fix) were divided into the following groups (n=10 in each group): (1) Conventional screw (Screw neck ø 1.5 mm) and (2) Experimental screw (screw neck constricted ø 1.2 mm). The abutments were tightened with a controlled torque meter device following the manufacturer's recommendations. Mechanical cycling was carried out with a load of 50 N.cm during 5 x 10 6 cycles with a frequency of 2 Hz at a temperature of 37°C (ISO 14801). A digital torque meter was used to measure the reverse torque values of the prosthetic screw and the micro abutment screw, before and after loading. Data were statistically analyzed by One-way Anova and Tukey test (95 %). The results of the mean values of torque loss of the micro abutment screw were 58.44 % for the control group and 55.31 % for the experimental group and the mean torque loss for the prosthetic screw was 53.3 % and 61.3 % of the conventional and experimental groups, respectively. The survival probability was 100 % for both screw groups. It was concluded that experimental screw showed a similar behavior to conventional screws, showing similar reliability after fatigue life testing.

RESUMEN: En implantología las fallas más habituales se deben a la inestabilidad mecánica. El aflojamiento del torque o la fractura de los tornillos son las complicaciones más frecuentes. Además, la recuperación del tornillo fracturado es complicada y requiere mucho tiempo. Por tanto, las modificaciones en el diseño de los sistemas de implantes están justificados para ofrecer un mayor grado de estabilidad biomecánica. Por lo tanto, el presente estudio propone evaluar una geometría experimental para tornillo de pilar en cuanto a probabilidad de falla y pérdida de torque. Se dividieron veinte conjuntos de implantes / pilares (e-fix, AS Technology - Titanium Fix) en los siguientes grupos (n = 10 en cada grupo): (1) Tornillo convencional (cuello de tornillo ø 1,5 mm) y (2) Tornillo experimental (cuello de rosca estrechado ø 1,2 mm). Los pilares se apretaron con un dispositivo medidor de torque controlado siguiendo las recomendaciones del fabricante. El ciclo mecánico se realizó con una carga de 50 N.cm durante 5 x 10 6 ciclos con una frecuencia de 2 Hz a una temperatura de 37° C (ISO 14801). Se utilizó un medidor de torque digital para medir los valores de torque inverso del tornillo protésico y el tornillo de micro pilar, antes y después de la carga. Los datos se analizaron estadísticamente mediante la prueba One-way Anova y Tukey (95%). Los resultados de los valores medios de pérdida de torque del micro tornillo de pilar fueron 58,44 % para el grupo de control y 55,31 % para el grupo experimental y la pérdida de torque media para el tornillo protésico fue 53,3 % y 61,3 % de los grupos convencional y experimental, respectivamente. La probabilidad de supervivencia fue del 100 % para ambos grupos de tornillos. Se concluyó que el tornillo experimental mostró un comportamiento similar a los tornillos convencionales, mostrando una fiabilidad similar después de la prueba de vida a fatiga.

Posterior rehabilitation using 3D-printed dental implants and synthetic regenerative biomaterials / Reabilitação posterior com implantes impressos e biomateriais sintéticos

Aim: To describe through a clinical case report the surgical sequence of rehabilitation with 3D-printed implants associated with maxillary sinus floor lift with synthetic regenerative materials, including biphasic bioceramic. Case Report: Patient had an agenesis of the upper left premolars (#12 and #13), a vertical bone deficiency caused by maxillary sinus' pneumatization, and a horizontal alveolar resorption around the missing teeth area. During the surgical procedures, incisions, detachment, and osteotomy were performed in the lateral region of the maxillary sinus. The sinus membrane was detached and lifted 10 mm. Then, a thick poly(dioxanone)-based synthetic resorbable membrane (Plenum) was inserted and adapted inside the sinus to protect the sinus membrane. After the osteotomies with sub-instrumentation, 3D-printed implants (Plenum) were installed in the #12 area (3.5mm x 11.5 mm; 30N) and #13 area (4.0mm x 10mm; 20N). The maxillary sinus was entirely filled with a biphasic bioceramic, HA/ß-TCP (70:30) 500-1000 µm (Plenum) and covered by the same synthetic resorbable membrane. Connective tissue graft from the palatal area was positioned internally to the flap and stabilized with sutures to improve the vestibular tissue architecture. The entire surgical wound was sutured, and the tissues stabilized. No complications occurred in the postoperative period. Conclusion: The use of synthetic regenerative memberane and 3D-printed implants seems to be a promising option in areas of deficient bone remnants (AU)

Objetivo: Descrever por meio de um relato de caso clínico a sequência cirúrgica de reabilitação com implantes obtidos por impressão 3D associados à elevação do assoalho do seio maxilar com materiais regenerativos sintéticos, incluindo uma biocerâmica bifásica. Relato de Caso: Paciente apresentava agenesia dos pré-molares superiores esquerdos (24 e 25), deficiência óssea vertical causada pela pneumatização do seio maxilar e reabsorção alveolar horizontal ao redor da área dos dentes ausentes. Durante os procedimentos cirúrgicos foram realizados incisões, descolamento e osteotomia na região lateral do seio maxilar. A membrana sinusal foi descolada e elevada 10 mm. Em seguida, uma membrana reabsorvível sintética à base de poli(dioxanona) espessa (Plenum) foi inserida e adaptada dentro do seio para proteger a membrana do seio. Após as osteotomias com subinstrumentação, implantes impressos em 3D (Plenum) foram instalados na área do 24 (3,5mm x 11,5mm; 30N) e na área do 25 (4,0mm x 10mm; 20N). O seio maxilar foi inteiramente preenchido com biocerâmica bifásica, HA/ß-TCP (70:30)500-1000 µm (Plenum) e recoberto pela mesma membrana sintética reabsorvível. O tecido conjuntivo da região palatina foi posicionado internamente ao retalho e estabilizado com suturas para melhorar a arquitetura do tecido vestibular. Toda a ferida cirúrgica foi suturada e os tecidos estabilizados. Não ocorreram complicações no pós-operatório. Conclusão:A utilização de biomateriais regenerativos sintéticos e implantes impressos parece ser uma opção promissora em áreas de remanescentes ósseos deficientes.(AU)

Effect of Titanium Hardness on the Integrity and Stress Concentration of External Hexagon Dental Implants

ABSTRACT: The aim of this study was to evaluate the influence of overtorque on integrity, strength and stress on external hexagonal implants (EH), with two different grades (N=10): conventional (C), grade 4; and modified (M), grade 4 with thermal treatment. The dimensions of EH were 3.75 x 13 mm; the specimens were fixed and submitted to SEM analysis and image acquisition. The abutment was then retained with 70 N/cm, re-analyzed by SEM, and a second image was obtained. The images were analyzed by Image J software (1.44o- NIH, USA) for dimensional variations measurement on surface of the hexagonal area. The finite element method was applied with a similar compliance to calculate the resultant stress (MPa) during the torque. Results were statistically analyzed with t-student test (5 %). The dimensional accuracy of M (0.22 mm2) was statistically significant (p<0.05). Minimum principal stress and von-Mises stress of C (-19.95 MPa, -19.94 MPa), were lower than M values (-55.83 MPa, -55.96 MPa), respectively. However, the M group showed lower deformation than C group. Therefore, more rigid titanium alloy is a promising alternative to avoid plastic deformation of prosthetic connec tions even concentrating higher stress magnitude on its structure.

RESUMEN: El objetivo de este estudio fue evaluar la influencia del sobrepar en la integridad, la fuerza y la tensión en los implantes hexagonales externos (EH), con dos grados diferentes (N = 10): convencional (C), grado 4; y modificado (M), grado 4 con tratamiento térmico. Las dimensiones de EH eran 3,75 de diámetro x 13 mm de longitud; las muestras se fijaron y se sometieron a análisis SEM y adquisición de imágenes. A continuación, el pilar se retuvo con 70 N / cm, se volvió a analizar por SEM y se obtuvo una segunda imagen. Las imágenes se analizaron con el software Image J (1.44o-NIH, EE. UU.) Para medir las variaciones dimensionales en la superficie superior del área hexagonal, que fue causada por un par excesivo. El método de los elementos finitos se aplicó con un cumplimiento similar para calcular la tensión resultante (MPa) durante el par. Los resultados se analizaron estadísticamente con la prueba t-student (5 %). La precisión dimensional de M (0,22 mm2) fue estadísticamente significativa (p <0,05). La tensión principal mínima y la tensión de von-Mises de C (-19,95 MPa, -19,94 MPa), fueron inferiores a los valores de M (-55,83 MPa, -55,96 MPa), respectivamente. Sin embargo, el hexágono del grupo M mostró menor deformación que el grupo C. Por lo tanto, la aleación de titanio más rígida es una alternativa prometedora para evitar la deformación plástica de las conexiones protésicas incluso concentrando una mayor magnitud de tensión en su estructura.

Metal Alloys in Dentistry: An Outdated Material or Required for Oral Rehabilitation?

ABSTRACT: The present study aims to describe through a literature review, the main types of noble and non-noble alloys in dentistry looking to identify the adhesion mechanisms, compositions and mechanical properties, and its applicability as a rehabilitation resource nowadays. A bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 1971 to 2021 were collected. Laboratory studies, case reports, systematic and literature reviews, which were developed in living individuals. Articles that did not deal with metal alloys and its use in dentistry were excluded. Through the review, it was possible to ver ify that all works presented the metal alloys and their main properties, indicating that they are divided into three main types: hi gh noble alloys, noble alloys and base metal alloys differing in their levels of constituent noble metals. Several alloys and meta ls are available for the dental market each presenting advantages and disadvantages, mainly based on its specific composition.Continuous research and development are resulting in the production of new technologies and products, giving dental surgeons even more options in the design and manufacture of restorations using metal alloys and understanding that these resources will still be viable alternatives in oral rehabilitations. However, further studies on metal alloys are needed to better understand this subject.

RESUMEN: El presente trabajo tuvo como objetivo describir a través de una revisión de la literatura, los principales tipos de aleaciones nobles y no nobles utilizados en odontología buscando identificar los mecanismos de adhesión, composiciones y propiedades mecánicas, así como reflejar su aplicabilidad como recurso rehabilitador en la actualidad. Realizamos una búsqueda bibliográfica em las principales bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en la que se recopilaron estudios publicados desde 1971 hasta 2021. Estudios de laboratorio, informes de casos, revisiones sistemáticas y bibliográficas, que se desarrollaron en individuos vivos. Sin embargo, se excluyeron los artículos que no trataban sobre aleaciones metálicas y su uso en odontología. Se pudo observar que todos los trabajos presentaban las aleaciones metálicas y sus principales propiedades indicando que se estas dividen en tres tipos principales: aleaciones altamente nobles, aleaciones nobles y aleaciones de metales base que difierenen sus niveles de metales nobles constituyentes. Hay varias aleaciones y metales disponibles para el mercado dental, cada uno presenta ventajas y desventajas, principalmente en función de su composición específica. La investigación y el desarrollo continuo están dando como resultado la producción de nuevas tecnologías y productos, brindando a los cirujanos dentistas aún más opciones en el diseño y fabricación de las restauraciones, utilizando aleaciones metálicas y, permite concluir que estos recursos seguirán siendo alternativas viables en los tratamientos de rehabilitación. Sin embargo, se necesitan más estudios sobre el tema abordado en el trabajo, para una comprensión más profunda del tema.

CAD-FEA modeling and fracture resistance of bilayer zirconia crowns manufactured by the rapid layer technology

Abstract In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system. The specimens were luted to an epoxy resin abutment with resin cement and mechanically cycled (200N and 4.5×105 Pa, 37°C, 2×106 cycles, 3Hz). The FR test was performed (10kN, 0.5mm/min), and the specimens were analyzed in a stereomicroscope. For the stress analysis (finite element analysis, FEA), a 10kN load was equal to the in vitro test, and the principal stress was evaluated. The FR data were analyzed by Student's t-test and Weibull's analysis. The thickness influenced the FR of bilayer crowns. The FR was higher in the TF2 than in the TF1 group. The TF2 group presented the highest characteristic strength compared to the group TF1. The predominant type of failure was delamination. The FEA showed higher stress concentrations below the loading application point at the veneering cement interface in the 1-mm-thick model. The bilayer crowns manufactured using the approach of 2mm of veneering ceramic promoted higher FR compared to the group with 1mm veneering ceramic. Also, the FEA showed that the veneer ceramic thickness has an effect on stress distribution in zirconia-based bilayer crowns.

Resumo Na RLT (Rapid Layer Technology), a cerâmica de cobertura e infraestrutura são fabricados pelo Computer-Aided Design / Computer-Aided Manufacturing (CAD / CAM) e cimentados para obter a restauração. Este estudo teve como objetivo avaliar o efeito da espessura da cerâmica de cobertura fabricada pela técnica RLT na resistência à fratura (RF) de coroas bilaminadas com infraestrutura de zircônia. Vinte infraestruturas de zircônia e vinte coroas posteriores feldspáticas com duas espessuras oclusais da cerâmica de cobertura (1mm = TF1; 2mm = TF2) foram fabricadas usando o sistema CAD / CAM. Os espécimes foram cimentados em preparos de resina epóxi com cimento resinoso dual e ciclados mecanicamente (200N e 4,5×105 Pa, 37° C, 2×106 ciclos, 3Hz). O teste de RF foi realizado (10kN, 0,5mm / min) e, posteriormente, os espécimes foram analisados em estereomicroscópio. Para a análise de tensão (análise de elementos finitos, FEA), uma carga de 10kN foi aplicada igual ao teste in vitro, e a tensão principal foi avaliada. Os dados de RF foram analisados pelo teste t de Student e análise de Weibull. A espessura mostrou forte influência na RF das coroas bilaminadas. A RF foi maior em TF2 do que no grupo TF1. O grupo TF2 apresentou a maior resistência característica em relação ao grupo TF1. O tipo de falha predominante foi a delaminação. O FEA mostrou maiores concentrações de tensões abaixo do ponto de aplicação da carga, na interface cimento e cerâmica de cobertura no modelo de coroa de 1 mm de espessura. As coroas de bilaminadas confeccionadas com 2 mm de cerâmica de cobertura promoveram maior RF em comparação ao grupo com cerâmica de cobertura de 1 mm. Além disso, a FEA mostrou que a espessura da cerâmica de cobertura tem um efeito na distribuição de tensões em coroas bilaminadas à base de zircônia.

Feldspathic and Lithium Disilicate Onlays with a 2-Year Follow-Up: Split-Mouth Randomized Clinical Trial

Abstract The present study was a prospective, controlled, randomized, clinical short-term trial aiming to evaluate the clinical performance of adhesively luted, lithium disilicate and feldspathic glass-ceramics onlays over a period up to 2 years. A total of 11 patients (7 female, 4 male; age range: 18-60 years, mean age: 39 years) were selected for this study. Each patient received a maximum of two restorations per group in a split-mouth-design. LD: Eleven onlays, performed with lithium disilicate-based ceramic (IPS e.max CAD, Ivoclar Vivadent, Schaan, Liechtenstein), and FP: Eleven onlays, performed with feldspathic ceramic (Vita Mark II, Vita Zanhfabrik, Bad Säckingen). Recalls were performed at 2 weeks (baseline = R1), 1 year (R2) and 2 years (R3) after the cementation by three calibrated blinded independent investigators using mirrors, magnifying eyeglasses, probes and bitewing radiographs. The postoperative sensitivity, secondary caries, marginal integrity, marginal discoloration, color match, surface roughness, tooth integrity, and restoration integrity were evaluated. The Friedman test was used to determine if there was a statistically significant difference in time-to-time comparison of the parameters in the ceramics restorations. A total of 95.4% of the restorations were clinically acceptable at the 2-year recall, without a difference for any evaluation parameter for both ceramic materials. Based on the 2-year data, the CAD-CAM onlays manufactured with feldspathic and lithium-disilicate based ceramics showed similar clinical performance.

Resumo O presente estudo é um estudo clínico prospectivo, controlado, randomizado e de longo curto prazo, com o objetivo de avaliar o desempenho clínico de restauraç ões adesivas cerâmica vítrea reforçada com dissilicato de lítio e cerâmica feldspática por um período de até 2 anos. Um total de 11 pacientes (7 mulheres, 4 homens; faixa etária: 18-60 anos, idade média: 39 anos) foram inseridas para este estudo. Cada paciente recebeu duas restaurações por grupo em um delineamento de boca dividida. LD: Onze onlays, realizados com cerâmica à base de dissilicato de lítio (IPS e.max CAD, Ivoclar Vivadent, Schaan, Liechtenstein); e FP: Onze onlays, realizados com cerâmica feldspática (Vita Mark II, Vita Zanhfabrik, Bad Säckingen). Os retornos foram realizados em 2 semanas (linha de base = R1), 1 ano (R2) e 2 anos (R3) após a cimentação, por três investigadores independentes, cegos e calibrados, usando espelhos, óculos de aumento, sondas e radiografias interproximais. Foram avaliadas a sensibilidade pós-operatória, cárie secundária, integridade marginal, descoloração marginal, correspondência de cores, rugosidade da superfície, integridade dentária e integridade da restauração. O teste de Friedman (95%) foi utilizado para determinar se havia uma diferença estatisticamente significante na comparação periódica dos parâmetros nas restaurações cerâmicas. Um total de 95,4% das restaurações estava clinicamente aceitável no retorno de 2 anos, sem diferença para qualquer parâmetro de avaliação para ambos os materiais cerâmicos. Com base nos dados de 2 anos, as restaurações CAD-CAM fabricados com cerâmica feldspática e à base de dissilicato de lítio apresentaram desempenho clínico semelhante.

Incidence of Fracture in Single Ceramic Crowns in Patients with Chronic Tooth Wear: A Clinical Follow-up

ABSTRACT: The aim of this study was to identify the incidence of fractures in single crowns placed in individuals with chronic tooth wear. The sample selection was performed based on the evaluation of 218 patient records rehabilitated with single crowns placed by the same professional from a private clinic. After exclusion criteria, 43 individuals (18 males and 25 females) were included and a total of 112 single crowns distributed in both jaws. Three ceramic systems were evaluated: 34 feldspathic all-ceramic, 38 metal-ceramic with a core in gold electropositive alloy, and 40 In-Ceram Alumina. The intraoral photograph analysis adopted a diagnosis method of tooth wear according to the morphological variations of the teeth. Of the 112 crowns evaluated, 47 were placed in male and 65 in female patients, aged between 21 to 74 years (mean 27.5 years old). The variables gender (p = 0.83), presence of chronic tooth wear (p = 0.91), ceramic system (p = 0.24) and crown location (p = 0.86) did not present a statistically difference. However, the variables pulp vitality (p = 0.04) and survi val time (p = 0.01) presented a statistically significant difference. The evaluated ceramic systems can be considered as alternativ es of restorative material, even in individuals with clinical characteristics suggestive of chronic tooth wear.

RESUMEN: El objetivo de este estudio fue identificar la incidencia de fracturas en coronas individuales colocadas en individuos con desgaste dental crónico. La selección de la muestra se realizó en base a la evaluación de 218 registros de pacientes rehabilitados con coronas individuales colocadas entre 1999 y 2009 por el mismo profesional de una clínica privada. Después de analizar los criterios de exclusión, se incluyeron 43 individuos (18 hombres y 25 mujeres) y un total de 112 coronas individuales distribuidas en ambas mandíbulas. Este estudio evaluó coronas hechas de tres sistemas cerámicos: 34 de cerámica totalmente feldespática, 38 de cerámica de metal con un núcleo de aleación electropositiva de oro y 40 de alúmina enceram. El análisis de la fotografía intraoral adoptó un método de diagnóstico del desgaste dental de acuerdo con las variaciones morfológicas de los dientes. De las 112 coronas evaluadas, 47 se colocaron en hombres y 65 en mujeres, con edades comprendidas entre 21 y 74 años (media de 27,5 años). Con respecto a las coronas individuales, las variables género (p = 0,83), presencia de desgaste dental crónico (p = 0,91), sistema cerámico (p = 0,24) y ubicación de la corona (p = 0,86) no presentaron una diferencia estadísticamente significativa. Sin embargo, las variables vitalidad pulpar (p = 0.04) y tiempo de supervivencia (p = 0.01) presentaron una diferencia estadísticamente significativa. Los sistemas cerámicos evaluados pueden considerarse como alternativas de material restaurador, incluso en individuos con características clínicas que sugieren desgaste dental crónico.

Characterization of Bulk-Fill Resin Composites in Terms of Physical, Chemical, Mechanical and Optical Properties and Clinical Behavior

ABSTRACT: This study aims to evaluate the physical, chemical, mechanical and optical properties of Bulk-Fill resin, in relation to the literature and its proper clinical uses. A bibliographic search was performed in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which articles published from 1994 to 2020 were collected. Laboratory studies, case reports, systematic reviews and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the characteristics of the Bulk-Fill resin and its proper clinical uses were excluded. The use of Bulk-Fill resin has been progressively increasing over the years, presenting good properties, achieving success in clinical performance, ease of handling and thus has become the material of choice for dentists. In addition, its longevity demonstrates durability with mechanical properties and resistance to tooth structure. Bulk - Fill resins have characteristics similar to traditional composite resins, when performed according the usage protocol. With the use of this group of resins in a single increment, possible failures that occur during the restorative procedure can be minimized, such as: less chance of incorporating bubbles and a volumetric contraction with less stress on the interface.

RESUMEN: Este estudio tuvo como objetivo evaluar las propiedades físicas, químicas, mecánicas y ópticas de la resina Bulk-Fill, en relación con la literatura y sus usos clínicos apropiados. Realizamos una búsqueda bibliográfica en las bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en la que se recopilaron trabajos que se publicaron entre 1994 y 2020. Fueron incluidos estudios de laboratorio, informes de casos, revisiones sistemáticas y revisiones de literatura, desarrollados en individuos vivos. Por tanto, se excluyeron los artículos que no trataban las características de la resina Bulk-Fill y sus usos clínicos adecuados. El uso de la resina Bulk-Fill ha ido aumentando progresivamente a lo largo de los años, presentando buenas propiedades, logrando éxito en el rendimiento clínico, facilidad de manejo y, por lo tanto, se ha convertido en el material elegido por los dentistas. Además, su longevidad demuestra durabilidad, con propiedades mecánicas y resistencia a la estructura dental.Las resinas Bulk-Fill tienen características similares a las resinas compuestas tradicionales, cuando se realizan siguiendo el protocolo de uso. Con el uso de este grupo de resinas mono incremental, es posible eliminar el paso de varios incrementos, disminuyendo a su vez el tiempo clínico. Además, se pueden minimizar las posibles fallas que se producen durante el procedimiento de restauración, tales como: menos posibilidades de incorporar burbujas y una contracción volumétrica con menos estrés en la interfaz.

Microhardness and Diametral Compression Strength of Single Fill Composite

ABSTRACT: To evaluate Knoop microhardness and diametral compression strength at different polymerization times. A total of 80 cylindrical samples with Filtek resin™ One Bulk Fill were made to perform the in vitro study, using half of total samples (n=40) for each test and divided equally between groups (n=10). All samples were made according to ISO 4049 using 2 mm thickness Teflon matrix and a central orifice with 4 mm diameter. Four different times of light-curing in Standard mode suggested by the light-unit manufacturer were selected, therefore, group 1 samples (G1) were light-cured for 5 seconds; group 2 (G2) for 10 seconds; group 3 (G3) for 15 seconds, and group 4 (G4) for 20 seconds. A radiant display, which means a power in mW/cm2 by time in seconds was expressed in Joules (J). The samples were stored in a dark container with distilled water at a temperature of 37°C for 48 hours before testing. One-way analysis of variance (ANOVA) with T-Test (LSD) of multiple comparisons of the mean values of Knoop hardness and diametral compression strength was performed, with significance index α=0.05. Regarding the Knoop microhardness test, G1 (35.73 ± 6.2) presented the lowest values, followed by G2, while G3 and G4 did not present statistical differences between them. For the diametral compression test, G1 (1387.76 ± 190.51) obtained the lowest value when compared to the other groups. G2, G3, and G4 did not present significant statistical differences. The different polymerization times influenced the Knoop microhardness and the diametral compression strength of Bulk Fill resin.

RESUMEN: El objetivo de este trabajo fue evaluar la microdureza Knoop y la resistencia a la compresión diametral en diferentes tiempos de polimerización. En el estudio realizado in vitro, se analizó un total de 80 muestras cilíndricas con la resina Filtek™ One Bulk Fill, utilizando la mitad (n=40) para cada prueba realizada y dividida en partes iguales entre los grupos (n=10). Todas las muestras se tomaron de acuerdo con ISO 4049 utilizando matrices de teflón de 2 mm de espesor y orificio central con 4 mm de diámetro. Se seleccionó cuatro veces el fotocurado de manera estándar, sugerido por el fabricante. Por lo tanto, las muestras del grupo 1 (G1) se fotopolimerizaron durante 5 segundos; grupo 2 (G2) durante 10 segundos; grupo 3 (G3) durante 15 segundos y grupo 4 (G4) durante 20 segundos. La exposición radiante, que indica la potencia en mW / cm2 a lo largo del tiempo en segundos, se expresó en julios (J). Las muestras se almacenaron en un recipiente oscuro con agua destilada en una estufa a una temperatura de 37°C durante 48 horas antes del ensayo. Se realizó para comparaciones múltiples de los valores medios, análisis de varianza (ANOVA) de un criterio con la prueba T (LSD) tanto de la dureza de Knoop como de la compresión diametral con un índice de significación α=0.05. Con respecto a la prueba de microdureza de Knoop, G1 (35,73 ± 6,2) tuvo los valores más bajos, seguido de G2, mientras que G3 y G4 no mostraron diferencias estadísticas entre ellos. Para la prueba de compresión diametral, G1 (1387.76 ± 190.51) obtuvo el valor más bajo en comparación con los otros grupos. G2, G3 y G4 no presentaron diferencias estadísticamente significativas. Los diferentes tiempos de polimerización influyeron en la microdureza de Knoop y la resistencia a la compresión diametral de la resina compuesta mono incremental.

Homogenous Bone Grafts as an Alternative in Oral Rehabilitation Treatments with Dental Implants / Los Injertos Óseos Homogéneos como una Alternativa en los Tratamientos de Rehabilitación Oral con Implantes Dentales

ABSTRACT: The present study aims to describe, through a case report, the functioning of bone grafts, where they are obtained including bone banks and the different dental areas in which it is used. A 50-year.old female patient HMR, sought the postgraduate college of dentistry CECAPE for oral rehabilitation. The initial clinical examination revealed the absence of several dental elements in both the maxilla and mandi ble, bone resorption in the entire maxillary extension where there was an absence of elements in the anterior region and the presence of a torus in the palatal region. Initial tomographic examinations of the maxilla and mandible were performed, looking for the best conduct regarding the diagnosis and planning of the case. After the clinical and radiographic examinations was performed, and the diagnosis was reached, it was determined as a treatment for oral rehabilitation of the maxilla, bone grafting and an Implant-supported Removable Partial Prosthesis and for the mandible a Dento-muco-supported Removable Partial Prosthesis. Dental treatments and oral rehabilitation from the use of bone tissues and bone grafting have become commonly used. Procedures that would normally lead to failure started to increase the percentage of successes due to the use of these biomaterials. The use of bone grafts in dentistry has been shown to be a very effective and useful resource, considering its great applicability in bone reconstructions in different areas of dentistry.

RESUMEN: El presente estudio tiene como objetivo describir a través de un informe de caso, el funcionamiento de los injertos óseos, donde se obtienen, incluidos los bancos de huesos y las diferentes áreas dentales en las que se emplea. Una paciente HMR, de 50 años de edad, asistió el centro universitario de posgrado CECAPE para rehabilitación oral. El examen clínico inicial reveló la ausencia de varios dientes tanto en el maxilar como en la mandíbula, la resorción ósea en toda la extensión maxilar donde había ausencia de dientes en la región anterior y la presencia de un torus en la región palatina. Se realizaron exámenes tomográficos iniciales del maxilar y mandíbula, buscando la mejor conducta con respecto al diagnóstico y la planificación del caso. Después de los exámenes clínicos y radiográficos realizados y el diagnóstico listo, se determinó como un tratamiento para la rehabilitación oral del maxilar, el injerto óseo y una prótesis removible implantosoportada y para la mandíbula una prótesis parcial removible dento-muco-soportada. Los tratamientos dentales y la rehabilitación oral a partir del uso de tejidos óseos y el injerto óseo se han utilizado comúnmente. Los procedimientos que normalmente conducirían al fracaso comenzaron a aumentar el porcentaje de éxitos debido al uso de estos biomateriales. Se ha demostrado que el uso de injertos óseos en odontología es un recurso muy eficaz y útil, considerando su gran aplicabilidad en las reconstrucciones óseas en diferentes áreas de la odontología.

Considerações Atuais Quanto as Cerâmicas Odontológicas e Seus Respectivos Sistemas de União / Current Considerations for Dental Ceramics and Their Respective Union Systems

Objetivo: avaliar as principais caracteristicas das cerâmicas odontológicas, cimentos resinosos, tratamentos de superfície e verificação dos seus devidos modos de falha, frente à literatura e suas respectivas utilizações clínicas. Material e Métodos: foi realizada uma busca bibliográfica nos principais bancos de dados de saúde PUBMED (www.pubmed.gov) e Scholar Google (www.scholar.google.com.br), no qual coletou-se trabalhos que foram publicados de 2002 a 2020. Foram inclusos estudos laboratoriais, relatos de casos, revisões sistemáticas e revisões de literatura, que fossem desenvolvidos em indivíduos vivos. Logo, foram excluídos artigos que não tratavam a respeito das caracteristicas das cerâmicas odontológicas, cimentos resinosos, tratamentos de superfície e verificação dos seus devidos modos de falha, frente à literatura e suas respectivas utilizações clínicas. Resultados: as cerâmicas podem ser classificadas em cerâmicas vítreas, cerâmicas policristalinas e as cerâmicas híbridas. Do mesmo modo que existem diferentes composições das cerâmicas e agentes de união, há também alguns protocolos de tratamento de superfície que se diferem de acordo com a escolha desses materiais. Conclusão: diversos sistemas cerâmicos estão disponíveis no mercado, fazendo com que os profissionais da área protética necessitem de uma constante reciclagem acerca das suas propriedades e indicações, visto que bons resultados não são devidos exclusivamente ao tipo de material utilizado, mas sim, à seleção do melhor material, tipo de preparo em conjunto à habilidade do profissional, cimentos resinosos, tratamentos de superfície e verificação dos seus devidos modos de falha. Nesse contexto, fazem-se necessários maiores estudos com relação às cerâmicas odontológicas e seu devido uso em um cenário clínico

Objective: to evaluate the main characteristics of dental ceramics, resin cements, surface treatments and verification of their failure modes, in relation to the literature and their respective clinical uses. Material and Methods: a bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 2002 to 2020 were collected. Laboratory studies, case reports, systematic and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the main characteristics of dental ceramics, resin cements, surface treatments and verification of their failure modes, in relation to the literature and their respective clinical uses were excluded. Results: ceramics can be classified into glass-matrix ceramics, polycrystalline ceramics and hybrid ceramics. Just as there are different compositions of ceramics and bonding agents, there are also some surface treatment protocols that vary according to the choice of these materials. Conclusion: several ceramic systems are available, making professionals in the prosthetic area need a constant update about their properties and indications, since good results are not due exclusively to the type of material used, but also to the selection of the best material, type of preparation, professional's skill, resin cements, surface treatments and verification of their failure modes. In this context, further studies are needed in relation to dental ceramics and their proper clinical use

Influência do Condicionamento Ácido na Resistência de União entre Cerâmica Feldspática e Cimento Resinoso / Influence of Acid Etching on Bond Strength Between Feldspathic Ceramics and Resin Cement

Objetivo: Analisar a influência da resistência de união entre cimento resinoso e cerâmica feldspática utilizando concentrações e tempos de aplicação diferentes de acído fluorídrico (HF). Material e Métodos: Foram confeccionados 18 discos de cerâmica feldspática (Ø10mm - 2mm de espessura) através da técnica incremental, que foram incluídos em resina acrílica e regularizados com lixas de carbeto de silício com granulações de 600, 1200 e 2000 através de uma máquina de polimento com velocidade de 600 rpm para regularização. Logo após foram mergulhadas em água destilada durante 10 minutos em cuba ultrassônica. Todos corpos de prova foram condicionados com HF e silanizados. Foram confeccionados quatro cilindros de cimento sobre cada corpo de prova (n=12), feitos com cimento resinoso Relyx ARC. Logo após, dividiu-se em seis grupos de acordo com o protocolo de tratamento de superfície: G1 (5% - 40s); G2 (5% - 60s); G3 (5% - 80s); G4 (10% - 40s); G5 (10% - 60s) e G6 (10% - 80s). Os corpos de prova foram submetidos ao Teste de Microcisalhamento, com força vertical a uma velocidade de 0,5 mm/min sobre a peça. A resistência de união ao microcisalhamento foi calculada e expressa em Megapascal (MPa). Os dados foram submetidos à análise de variância (ANOVA) dois fatores e para comparações múltiplas foi utilizado o Teste de Tukey, sendo o nível de significância de 5%. Resultados: Quando analisado a concentração do HF, não houve diferenças estatísticas (p>0,05). Na comparação dos tempos de aplicação, G3 (5% - 80s) e G6 (10% - 80s) obtiveram maiores resultados de resistência ao microcisalhamento que os demais grupos. Conclusão: As diferentes concentrações de HF não influenciaram na resistência de união entre cerâmica feldspática e cimento resinoso. Já o aumento do tempo de condicionamento com HF afetou na resistência de união

Objective: analyze the influence of bond strength between resin cement and feldspathic ceramics using different concentrations and application times of hydrofluoric acid (HF). Materials and Methods: 18 feldspathic ceramic discs (Ø10mm - 2mm thickness) were made through the incremental technique, which were included in acrylic resin and regularized with silicon carbide sandpaper with granulations of 600, 1200 and 2000 through a polishing machine with a speed of 600 rpm. Soon after, they were immersed in distilled water for 10 minutes in an ultrasonic bath. All specimens were conditioned with HF and silanized. Four cement cylinders were made on each specimen (n=12), manufactured with Relyx ARC resin cement. After that, it was divided into six groups according to the surface treatment protocol: G1 (5% - 40s); G2 (5% - 60s); G3 (5% - 80s); G4 (10% - 40s); G5 (10% - 60s) e G6 (10% - 80s). The specimens were subjected to the Microshear Test, with vertical force at a speed of 0.5 mm min on the specimen. The microshear bond strength was calculated and expressed in Megapascal (MPa). The data were submitted to two-way analysis of variance (ANOVA) and Tukey's test for multiple comparisons, with a significance level of 5%. Results: when the concentration of HF was analyzed, there were no statistical differences (p>0.05). In the comparison of application times, G3 (5% - 80s) and G6 (10% - 80s) obtained higher results of microshear resistance than the other groups. Conclusion: The different concentrations of HF did not influence the bond strength between feldspathic ceramics and resin cement. However, the increase in the time of HF conditioning affected in the bond strength.

Effect of glazing application side and mechanical cycling on the biaxial flexural strength and Weibull characteristics of a Y-TZP ceramic

Abstract Glaze application on monolithic zirconia (Y-TZP) can be a practical approach to improve the mechanical properties of this material. Objective Our study evaluated the effect of glazing side and mechanical cycling on the biaxial flexure strength (BFS) of a Y-TZP. Methodology Eighty sintered Y-TZP discs (Ø:12 mm; thickness: 1.2 mm - ISO 6872) were produced and randomly assigned into eight groups (n=10), according to the factors "glazing side" (control - no glazing; GT - glaze on tensile side; GC - glaze on compression side; GTC - glaze on both sides) and "mechanical aging" (non-aged and aged, A - mechanical cycling: 1.2×106, 84 N, 3 Hz, under water at 37°C). Specimens were subjected to BFS test (1 mm/min; 1,000 Kgf load cell) and fractured surfaces were analyzed by stereomicroscopy and SEM. Hsueh's rigorous solutions were used to estimate the stress at failure of glazed specimens. Two-way ANOVA, Tukey's test (5%), and Weibull analysis were performed. Results The "glazing side", "mechanical aging" and the interaction of the factors were significant (p<0.05). Groups GC (1157.9±146.9 MPa), GT (1156.1±195.3 MPa), GTC (986.0±187.4 MPa) and GTC-A (1131.9±128.9 MPa) presented higher BFS than control groups (Tukey, 5%). Hsueh's rigorous solutions showed that the maximum tensile stress was presented in the bottom of zirconia layer, at the zirconia/glaze interface. Weibull characteristic strength (σo) of the GC was higher than all groups (p<0.05), except to GT, GTC-A and GTC, which were similar among them. The fractography showed initiation of failures from zirconia the tensile side regardless of the side of glaze application and fatigue. Conclusion Glazing zirconia applied on both tensile and compression sides improves the flexural strength of Y-TZP, regardless the mechanical aging.