Resistência flexural de uma resina para impressão 3D comparada a resinas acrílicas convencionais empregadas para confecção de placas estabilizadoras de mordida / Flexural resistance of 3D printing resin compared to conventional acrylic resins employed to build occlusal bite splints

Introduction: with the technological advance in dentistry, light-polymerized three-dimensional (3D) printing resins had become an alternative for the manufacture of occlusal splint splints. Objective: the present study aimed to analyze the flexural strength of a resin for 3D printing compared to conventional acrylic resins (chemically activated and thermally activated), under the influence of thermocycling. Material and method: 60 specimens were made, which were distributed in six experimental groups (n = 10), according to the resin employed (chemically activated acrylic resin, thermally activated acrylic resin and 3D printing resin) and the treatment received (control and thermocycling). The specimens were submitted to flexural strength by the three-point flexural test. Result: data analysis showed that the material factor (<0.0001) and the thermocycling factor (p = 0.0096) influenced flexural strength, however, the interaction between the two factors did not (p = 0.9728). Conclusion: it was concluded that 3D printing resins presented the lowest flexural resistance to acrylic resins, especially when submitted to thermocycling.

Introdução: com o avanço tecnológico dentro da odontologia, as resinas fotopolimerizáveis para impressão tridimensional (3D) se tornaram uma alternativa para a fabricação de dispositivos interoclusais. Objetivo: o presente trabalho teve como objetivo analisar a resistência flexural de uma resina para impressão tridimensional comparada com resinas acrílicas convencionais (quimicamente ativada e termicamente ativada), sob a influência da termociclagem. Material e método: foram confeccionados 60 corpos de prova, que foram distribuídos aleatoriamente em seis grupos experimentais (n=10), de acordo com a resina utilizada (resina acrílica ativada quimicamente, resina acrílica ativada termicamente e resina para impressão 3D) e com o tratamento recebido (controle e termociclagem). Os corpos de prova foram submetidos ao ensaio de flexão de três pontos para determinação da resistência flexural. Resultado: a análise dos dados demonstrou que o fator material (<0.0001) e o fator termociclagem (p=0.0096) influenciaram a resistência flexural, entretanto, a interação entre os dois fatores não (p=0.9728). Conclusão: deste modo podemos concluir que a resina para impressão 3D apresentou desempenho inferior às resinas acrílicas, especialmente quando submetida a termociclagem.

Evaluation of tissue in repair with natural latex and / or hyaluronic acid in surgical bone defects.

This study evaluated the bone repair in surgical defects of rats treated with hyaluronic acid (HA) associated or not with Hevea brasiliensis fraction protein (F-1). Bone defect were created in 15 albino Wistar rats divided into 3 groups (n=5): Control group (1) - blood clot; HA group (2) - 0.5% hyaluronic acid; HAF1 group (3) - 0.1% F-1 protein fraction dissolved in 0.5% hyaluronic acid. After 4 weeks, the animals were euthanized and the bone repair was evaluated through histomorphometric analysis, zymography and immunohistochemistry. The neoformed bone area did not show a significant difference (p = 0.757), but there was a tendency for bone trabeculation to increase in the groups HA and HAF1. For immunohistochemically analysis, there was a difference in vascular endothelial growth factor (VEGF) labeling (p = 0.023), being higher in the groups HA and HAF1 than the control group. No significant difference in bone sialoprotein (BSP) (p = 0.681), osteocalcin (p = 0.954), however, significant difference in platelet endothelial cell adhesion molecule-1 (CD-31) (p = 0.040), with HAF1 group being significantly lower than the control. For zymographic analysis, there was no significant difference for metalloproteinase-2 (MMP-2) (p = 0.068), but there was a tendency to increase MMP-2 in the HA group. Despite the influence on angiogenic factors and the apparent tendency for greater trabeculation in the HA and HAF1 groups, there was no significant difference in the area of ​​newly formed bone tissue in the analyzed period.

Evaluation of tissue in repair with natural latex and / or hyaluronic acid in surgical bone defects

Abstract This study evaluated the bone repair in surgical defects of rats treated with hyaluronic acid (HA) associated or not with Hevea brasiliensis fraction protein (F-1). Bone defect were created in 15 albino Wistar rats divided into 3 groups (n=5): Control group (1) - blood clot; HA group (2) - 0.5% hyaluronic acid; HAF1 group (3) - 0.1% F-1 protein fraction dissolved in 0.5% hyaluronic acid. After 4 weeks, the animals were euthanized and the bone repair was evaluated through histomorphometric analysis, zymography and immunohistochemistry. The neoformed bone area did not show a significant difference (p = 0.757), but there was a tendency for bone trabeculation to increase in the groups HA and HAF1. For immunohistochemically analysis, there was a difference in vascular endothelial growth factor (VEGF) labeling (p = 0.023), being higher in the groups HA and HAF1 than the control group. No significant difference in bone sialoprotein (BSP) (p = 0.681), osteocalcin (p = 0.954), however, significant difference in platelet endothelial cell adhesion molecule-1 (CD-31) (p = 0.040), with HAF1 group being significantly lower than the control. For zymographic analysis, there was no significant difference for metalloproteinase-2 (MMP-2) (p = 0.068), but there was a tendency to increase MMP-2 in the HA group. Despite the influence on angiogenic factors and the apparent tendency for greater trabeculation in the HA and HAF1 groups, there was no significant difference in the area of ​​newly formed bone tissue in the analyzed period.

Resumo Este estudo avaliou o reparo ósseo em defeitos cirúrgicos de ratos tratados com ácido hialurônico (AH) associado ou não à fração proteica de Hevea brasiliensis (F-1). Foram criados defeitos ósseos em 15 ratos albinos Wistar divididos em 3 grupos (n = 5): Grupo controle (1) - coágulo sanguíneo; Grupo HA (2) - ácido hialurônico 0,5%; Grupo HAF1 (3) - fração proteica F-1 0,1% dissolvida em ácido hialurônico a 0,5%. Após 4 semanas, os animais foram submetidos à eutanásia e o reparo ósseo avaliado por meio de análise histomorfométrica, zimografia e imunohistoquímica. A área óssea neoformada não apresentou diferença significativa (p = 0,757), mas houve tendência de aumento da trabeculação óssea nos grupos HA e HAF1. Para a análise imunoistoquímica, houve diferença na marcação do fator de crescimento endotelial vascular (VEGF) (p = 0,023), sendo maior nos grupos HA e HAF1 do que no grupo controle. Nenhuma diferença significativa na sialoproteína óssea (BSP) (p = 0,681), osteocalcina (p = 0,954), no entanto, diferenças significativas foram encontradas para a molécula de adesão de células endoteliais plaquetárias-1 (CD-31) (p = 0,040), com o grupo HAF1 sendo significativamente inferior ao controle. Para a análise zimográfica, não houve diferença significativa para metaloproteinase-2 (MMP-2) (p = 0,068), mas houve tendência de aumento da MMP-2 no grupo HA. Apesar da influência sobre os fatores angiogênicos e da aparente tendência de maior trabeculação nos grupos HA e HAF1, não houve diferença significativa na área de tecido ósseo neoformado no período analisado.

Customized fiber posts in root canals prepared with and without laser application: a pull-out evaluation.

This study evaluated the effect of fiber post customization and laser application on the results of pull-out tests in endodontically treated teeth. Forty-eight bovine incisors were stored in aqueous 2% formaldehyde (pH 7.0) for 30 days. At the end of the storage period, the incisors were scraped with No. 11/12 periodontal curettes, rinsed with water and sodium bicarbonate, and stored in 0.9% saline solution for 7 days. Roots with similar shape and dimensions were selected and sectioned to a standard 17-mm length. Root canals were prepared and filled to a depth of 12 mm. The roots were divided into 4 groups (n = 12): 1, conventional fiber post and no laser application; 2, customized fiber post and no laser application; 3, conventional fiber post and laser application; and 4, customized fiber post and laser application. After removal of the obturation material for post space preparation, the canals were enlarged, and a laser beam was applied to the roots of teeth in groups 3 and 4 as an auxiliary disinfection procedure. After cementation of the posts, a pull-out test was performed using an axial tensile load at 0.5 mm/min in a universal testing machine. Analysis of variance and the Tukey test were used for statistical analysis of the results. The mean (SD) maximum tensile force was 10.18 (4.73) kgf in group 1, 38.89 (6.49) kgf in group 2, 27.74 (10.07) kgf in group 3, and 38.92 (6.89) kgf in group 4. These values were significantly higher in groups 2 and 4 than in group 1 (P < 0.05). The customization of fiber posts used for the restoration of pulpless teeth resulted in significantly (P < 0.05) greater pull-out test values, a thinner cement layer, and improved retention.

Genomic Evaluation of Formed Biofilm on Dental Implants with Different Surface Treatments Associated with Zirconia or Titanium Abutments: An In Vitro Study.

PURPOSE: The aim of this study was to evaluate the formed biofilm on two types of implant surfaces (hydrophilic or hydrophobic) associated with titanium (Ti) or zirconia (Zn) abutments. MATERIALS AND METHODS: Samples were separated into four groups according to type of surface and abutment used (n = 10): (1) hydrophobic/Ti abutment, (2) hydrophilic/Ti abutment, (3) hydrophobic/Zn abutment, and (4) hydrophilic/Zn abutment. Implant-abutment assemblies were incubated with human saliva and supragingival biofilm. Samples of biofilm were evaluated by DNA Checkerboard hybridization, identifying up to 41 species. Scanning electron microscopy (SEM) images were obtained from the implants and abutments. RESULTS: The microbial count was higher for samples from groups with the hydrophilic/Ti abutment, followed by hydrophobic/Zn abutment, hydrophilic/Ti abutment, and hydrophobic/Zn abutment (P < .05). Hydrophilic surfaces and Zn abutments showed the highest counts of microorganisms. Individual bacterial counts were variable between groups; the hydrophilic/Zn abutment group had the highest microbial diversity, including T forsythia, P nigrescens, S oralis, S sanguinis, L casei, M orale, P aeruginosa, P endodontalis, S aureus, S gallolyticus, S mutans, S parasanguinis, S pneumoniae, and C albicans. The hydrophilic/Ti abutment group had the highest count of T forsythia and T denticola, microorganisms of Socransky red complex. The SEM images showed the bacterial colonization in both surfaces of the implant and abutment. CONCLUSION: Different surfaces of implants and abutments showed significant differences in the count and diversity of species. The hydrophilic/Zn abutment group presented the highest count and diversity of target species.

Lactobacillus reuteri associated with scaling and root planing in the treatment of periodontitis in rats submitted to chemotherapy.

OBJECTIVE: The aim of this study was to evaluate the effects of Lactobacillus reuteri applied locally or systemically with scaling and root planing (SRP) to the treatment of experimental periodontitis (EP) in rats treated with 5-fluorouracil. METHODS: A cotton ligature was installed on the molars of rats. The animals (n = 54) underwent chemotherapy and were divided into groups: SRP (n = 18), scaling and root planing only; LP (n = 18), SRP and 4 sessions of local probiotic (PRO); SP, SRP and 4 sessions of systemic PRO. The molar furcation area was submitted to histopathological, histometric of alveolar bone loss (ABL) and immunolabeling analysis after euthanasia at 7, 15 and 30 days. The data were submitted to statistical analysis (α = 5%). RESULTS: At 15 days ABL was higher in LP compared to SP. At 30 days, ABL was higher in LP compared to SRP and SP. Higher immunolabeling of TGF-ß1 was observed in LP and SP at 7 days compared to SRP (p < 0.05). Lower immunolabeling of OCN and higher immunolabeling of RANKL were observed at all periods in SRP compared to SP (p < 0.05). At 30 days, SRP showed lower immunolabeling of OPG compared to SP and LP (p < 0.05). In SP, lower immunolabeling was observed at 15 days compared at 30 days (p < 0.05). CONCLUSION: The ABL was similar among the groups treated with SRP associated or not to probiotic therapeutic, although the systemic use of Lactobacillus reuteri considerably reduced inflammation and favored periodontal tissues repair.

Reconstrução estética anterior baseada no planejamento digital do sorriso / Aesthetic reconstruction of anterior teeth based on digital smile design

A reabilitação funcional e estética com cerâmicas adesivas é uma área da Odontologia em destaque tanto pelos resultados excepcionais que podem ser alcançados como pela demanda da sociedade contemporânea. Várias ferramentas de diagnóstico, planejamento e execução estão disponíveis com o objetivo de alcançar a excelência no tratamento reabilitador estético. O desenho digital do sorriso (DSD) é um dos recursos utilizados, possibilitando além da previsibilidade, comunicação e orientação eficiente da fase laboratorial, também a motivação do paciente. O objetivo desse trabalho foi apresentar um caso clínico de reabilitação oral estética guiado pelo DSD tanto para a abordagem periodontal como para o enceramento estético. Foram planejados e executados 10 laminados cerâmicos em dissilicato de lítio tendo como ponto de partida após exames clínicos, o enceramento e a plástica periodontal virtualmente desenhados. O resultado foi alcançado como almejado pelo paciente e previsto pelo profissional, sendo a presente reabilitação apoiada em criterioso protocolo de execução(AU)

Functional and aesthetic rehabilitation with adhesive ceramics is an area of dentistry that stands out both for the exceptional results that can be achieved and for the demands of contemporary society. Various diagnostic, planning and execution tools are available with the goal of achieving excellence in aesthetic rehabilitation treatment. The digital smile design (DSD) is one of the resources used, enabling not only the predictability, communication and efficient orientation of the laboratory phase, but also the motivation of the patient. The objective of this work was to present a clinical case of oral aesthetic rehabilitation guided by DSD for both the periodontal approach and aesthetic waxing. Ten ceramic laminates in lithium disilicate were designed and executed with virtually new clinical waxing and periodontal plastic as a starting point after clinical examination. The result was achieved as intended by the patient and predicted by the professional, and the present rehabilitation is supported by a judicious implementation protocol(AU)

Plástica gengival guiada pelo ensaio estético e associada às lentes de contato: cinco anos de acompanhamento / Periodontal plastic surgery guided by mock-ups and associated with contact lenses for the harmonization of pink and white esthetics: 5 years of follow-up

O contorno gengival é um aspecto de extrema importância para a harmonia do sorriso. Nos sorrisos classificados como altos e com margens cervicais irregulares, para otimizar os resultados de um tratamento estético-reabilitador, é necessária a remodelação do tecido gengival com o uso de técnicas de cirurgia plástica periodontal, como a gengivectomia e/ou gengivoplastia em associação aos procedimentos restauradores. Atualmente, faz parte do protocolo reabilitador o ensaio estético ou mock-up, cujo objetivo é demonstrar ao paciente o tratamento a ser executado, prever a finalização estética e auxiliar na cirurgia periodontal. O uso do mock-up é uma excelente ferramenta para diagnóstico, planejamento e execução de procedimentos cirúrgicos-reabilitadores, dando previsibilidade ao resultado estético e funcional. Dessa forma, o objetivo deste trabalho foi revisar a literatura acerca da utilização do mock-up em procedimentos cirúrgico-reabilitadores, bem como relatar o caso clínico de uma paciente na qual se aplicou o ensaio estético para guiar a cirurgia plástica periodontal e prever o resultado a ser alcançado nos procedimentos restauradores. Assim, os profissionais podem ter previsibilidade de seus tratamentos estéticos associando o enceramento de diagnóstico ao ensaio estético, e este guiando o recontorno das margens gengivais que trará harmonia entre os tecidos da estética branca e estética rosa com excelentes resultados, principalmente nos casos de sorriso gengival alto.

The gingival contour is an aspect of extreme importance for the harmony of the smile. For smiles classified as high and with irregular cervical margins, in order to optimize the results of an aesthetic-rehabilitation treatment, it is necessary to remodel the gingival tissue with periodontal plastic surgery techniques, such as gingivectomy and/or gingivoplasty associated to restorative procedures. Currently, part of the rehabilitation protocol is the aesthetic or mock-up test, whose objective is to demonstrate to the patient the treatment to be performed, to predict aesthetic completion, and to assist in periodontal surgery. The mock-up is an excellent tool for diagnosis, planning and execution of surgical-rehabilitation procedures, giving predictability to the aesthetic and functional result. Thus, the objective of this work was to review the literature on the use of mock-up in surgical-rehabilitation procedures, as well as to report the clinical case of a patient in whom the esthetic test was applied to guide the periodontal plastic surgery and predict the result to be achieved in restorative procedures. Thus, professionals can have predictability of their aesthetic treatments by associating diagnostic waxing with the aesthetic test and this guiding the contouring of the gingival margins that will bring harmony between the tissues of pink and white esthetics with excellent results, especially in cases of high gingival smile.