No abstract

Background: This experimental study assessed reverse torque of indexed and nonindexed (NI) abutments in Morse Taper (MT) implants in a mechanical fatigue test. Materials and Methods: In this experimental study It was used 37 implants MT and over them installed Pilar Flex abutments (4.8 mm × 6 mm × 1.5 mm). The groups were as follows: Group A used 19 MT implants with a NI Pilar Flex abutment loaded with 32 N/cm and Group B used 18 MT implants with an indexed (IN) Pilar Flex abutment loaded with 20 N/cm. The abutments were tested according to ISO standard 14801/2007. The specimens were installed at 30° from the axial axis and underwent a 133 N load, 4 Hz frequency, and 1,000,000 cycles. Once the test was completed, the reverse torque was provided by an electronic torque meter. Data were submitted to statistical analysis using the t -test for independent samples and paired t -test. The significance level was considered P < 0.05. Results: Results obtained showed that the indexed Pilar Flex abutment had a percentage of torque loss from the initial torque of 49% and the NI Pilar Flex abutment lost 14%. Paired Student's t -tests revealed that for both NI ( P < 0.001) and indexed ( P < 0.001) abutments, the counter torque values were significantly lower than those applied at the initial torque. Conclusion: According on the methodology used, the NI Pilar Flex abutment was more effective regarding the reverse torque in single-unit implant prostheses versus the indexed Pilar Flex abutment. A greater loosening in the indexed Pilar Flex abutment retaining screw was noted in the reverse torque test, and the Pilar Flex abutment failed to show good outcomes related to the cold welding effect.

Desde que foram registrados os primeiros contágios, uma infecção por coronavírus (Covid-19) deu uma maneira bastante rápida. Neste cenário, dentre os EPI's (Equipamentos de Proteção Individual), os que mais ganharam destaque no combate à doença foram as máscaras cirúrgicas como forma de prevenção desse contágio. Alguns protocolos devem ser seguidos para usar como máscaras de maneira correta. Além das máscaras cirúrgicas, nos casos aplicáveis, faz-se necessário o uso de máscaras de proteção respiratória. No entanto, como máscaras cirúrgicas e de proteção respiratória cirúrgica vem desempenhando um papel importante no controle da disseminação desse microrganismo e são monitorados por um excelente método de acesso acessível.

A cavidade oral apresenta características bastante abrangentes para o desenvolvimento de microorganismos e é considerada uma abertura para a entrada dos mesmos. Microrganismos causados ​​pela boca podem causar infecções generalizadas, como pneumonia e sepse. Em pacientes internados em unidades de terapia intensiva (UTIs), muitas dessas complicações podem ser evitadas caso o tratamento esteja vinculado a um atendimento odontológico. Esses atendimentos são feitos nas luvas e realizados por cirurgiões dentistas da UTI. Frente a Pandemia que vive nos dias de hoje, criou um protocolo de alta proteção bucal e, caso haja necessidade de intervenção odontológica na UTI, na frente de coronavírus. Dessa forma, é essencial que os cirurgiões dentistas,assim como os demais profissionais que trabalham nas UTIs no dia a dia como medidas preventivas preconizadas para diminuir o risco de contaminação e transmissão. Dessa forma, haverá mais segurança para a equipe, o paciente e o próprio profissional.

The aim of this study is to test and compare the flexural strength of milled polymer bars, with and without glass fiber reinforcement. The number of samples in the study was defined through a pilot study on a universal testing machine (EMIC) (n = 5). The brands analyzed in this study were Arch Free Metal, Zantex, Bioplas and PEEK. All samples were submitted to thermal aging before the three-point flexural test. Fracture patterns were analyzed using a Scanning Electron Microscope. Results show that the Arch Free Metal bar presented the largest flexural strength, followed by Zantex and PEEK bars, that lacked statistical difference, and Bioplas bars. Regarding fracture patterns, Arch Free Metal and Zantex bars were partially fractured and showed partial glass fiber rupture; PEEK bars were not fractured and showed plastic behavior; and Bioplas bars were fractured. It is possible to conclude that the reinforced polymer bar Arch Free Metal has a better performance in terms of flexural strength than the other tested materials.