Effect of Antimicrobial Agent Coating on Physicochemical and Biologic Properties of Implant Abutments: A Systematic Review.

PURPOSE: To analyze the effectiveness of coating of abutments with antimicrobial agents and their influence on the physicochemical and biologic properties of the coated materials. MATERIALS AND METHODS: This work was registered in Open Science Framework (osf.io/6tkcp) and followed the PRISMA protocols. A search of two independent reviewers of articles published up to October 29, 2021, was performed in the Embase, PubMed, Science Direct, and Scopus databases. RESULTS: The databases found a total of 1,474 references. After excluding the duplicates, 1,050 remained. After reading the titles and abstracts and applying the inclusion criteria, 13 articles remained and were read in full. A total of 8 articles were included in this systematic review. Different antimicrobial agents have been used to coat abutments, including graphene oxide, polydopamine, titanium and zirconium nitride, lactoferrin, tetracycline, silver, and doxycycline with varied release times. Titanium-coated silver showed a better antimicrobial agent release time of up to 28 days. Chemical analysis confirmed the presence of antimicrobials on the surface after coating. Different pathogenic microorganisms, such as Streptococcus sanguinis, Streptococcus oralis, and Staphylococcus aureus, were inhibited when in contact with the coated surface. CONCLUSIONS: This review showed that there is still no consensus on which is the better antimicrobial agent and which coated materials have the better performance. However, the association of surface coating of abutments with antimicrobials is feasible and can benefit many patients, which can support their clinical use to favor the healing process and prevent infections that can lead to treatment failure with dental implants.

Mechanical and microbiological properties of orthodontic resin modified with nanostructured silver vanadate decorated with silver nanoparticles (ßAgVO3).

OBJECTIVE: To investigate the impact of incorporating the antimicrobial nanomaterial ß-AgVO3 into orthodontic resin, focusing on degree of conversion, surface characteristics, microhardness, adhesion properties, and antimicrobial activity. METHODS: The 3 M Transbond XT resin underwent modification, resulting in three groups (Control, 2.5% addition, 5% addition) with 20 specimens each. Fourier transform infrared spectroscopy assessed monomer conversion. Laser confocal microscopy examined surface roughness, and microhardness was evaluated using Knoop protocols. Shear strength was measured before and after artificial aging on 36 premolar teeth. Microbiological analysis against S. mutans and S. sanguinis was conducted using the agar diffusion method. RESULTS: Degree of conversion remained unaffected by time (P = 0.797), concentration (P = 0.438), or their interaction (P = 0.187). The 5% group exhibited the lowest surface roughness, differing significantly from the control group (P = 0.045). Microhardness showed no significant differences between concentrations (P = 0.740). Shear strength was highest in the control group (P < 0.001). No significant differences were observed in the samples with or without thermocycling (P = 0.759). Microbial analysis revealed concentration-dependent variations, with the 5% group exhibiting the largest inhibition halo (P < 0.001). CONCLUSIONS: Incorporating ß-AgVO3 at 2.5% and 5% concentrations led to significant differences in surface roughness, adhesion, and antimicrobial activity. Overall, resin modification positively impacted degree of conversion, surface characteristics, microhardness, and antimicrobial activity. Further research is warranted to determine clinically optimal concentrations that maximize antimicrobial benefits while minimizing adverse effects on adhesion properties. CLINICAL SIGNIFICANCE: Incorporating ß-AgVO3 into orthodontic resin could improve patient quality of life by prolonging intervention durability and reducing the impact of cariogenic microorganisms. The study's findings also hold promise for the industry, paving the way for the development of new materials with antimicrobial properties for potential applications in the health sector.

Insertion torque, flexural strength and surface alterations of stainless steel and titanium alloy orthodontic mini-implants: an in vitro study.

OBJECTIVE: This study aimed to compare the insertion torque (IT), flexural strength (FS) and surface alterations between stainless steel (SS-MIs) and titanium alloy (Ti-MIs) orthodontic mini-implants. METHODS: Twenty-four MIs (2 x 10 mm; SS-MIs, n = 12; Ti-MIs, n = 12) were inserted on artificial bone blocks of 20 lb/ft3 (20 PCF) and 40 lb/ft3 (40 PCF) density. The maximum IT was recorded using a digital torque meter. FS was evaluated at 2, 3 and 4 mm-deflection. Surface topography and chemical composition of MIs were assessed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). General linear and mixed models were used to assess the effect of the MI type, bone density and deflection on the evaluated outcomes. RESULTS: The IT of Ti-MIs was 1.1 Ncm greater than that obtained for the SS-MIs (p= 0.018). The IT for MIs inserted in 40 PCF test blocks was 5.4 Ncm greater than that for those inserted in 20 PCF test blocks (p < 0.001). SS-MIs inserted in higher density bone (40 PCF) had significantly higher flexural strength than the other groups, at 2 mm (98.7 ± 5.1 Ncm), 3 mm (112.0 ± 3.9 Ncm) and 4 mm (120.0 ± 3.4 Ncm) of deflection (p< 0.001). SEM evidenced fractures in the Ti-MIs. EDS revealed incorporation of 18% of C and 2.06% of O in the loaded SS-MIs, and 3.91% of C in the loaded Ti-MIs. CONCLUSIONS: Based on the findings of this in vitro study, it seems that SS-MIs offer sufficient stability and exhibit greater mechanical strength, compared to Ti-MIs when inserted into higher density bone.

Insertion torque, flexural strength and surface alterations of stainless steel and titanium alloy orthodontic mini-implants: an in vitro study

ABSTRACT Objective: This study aimed to compare the insertion torque (IT), flexural strength (FS) and surface alterations between stainless steel (SS-MIs) and titanium alloy (Ti-MIs) orthodontic mini-implants. Methods: Twenty-four MIs (2 x 10 mm; SS-MIs, n = 12; Ti-MIs, n = 12) were inserted on artificial bone blocks of 20 lb/ft3 (20 PCF) and 40 lb/ft3 (40 PCF) density. The maximum IT was recorded using a digital torque meter. FS was evaluated at 2, 3 and 4 mm-deflection. Surface topography and chemical composition of MIs were assessed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). General linear and mixed models were used to assess the effect of the MI type, bone density and deflection on the evaluated outcomes. Results: The IT of Ti-MIs was 1.1 Ncm greater than that obtained for the SS-MIs (p= 0.018). The IT for MIs inserted in 40 PCF test blocks was 5.4 Ncm greater than that for those inserted in 20 PCF test blocks (p < 0.001). SS-MIs inserted in higher density bone (40 PCF) had significantly higher flexural strength than the other groups, at 2 mm (98.7 ± 5.1 Ncm), 3 mm (112.0 ± 3.9 Ncm) and 4 mm (120.0 ± 3.4 Ncm) of deflection (p< 0.001). SEM evidenced fractures in the Ti-MIs. EDS revealed incorporation of 18% of C and 2.06% of O in the loaded SS-MIs, and 3.91% of C in the loaded Ti-MIs. Conclusions: Based on the findings of this in vitro study, it seems that SS-MIs offer sufficient stability and exhibit greater mechanical strength, compared to Ti-MIs when inserted into higher density bone.

RESUMO Objetivo: O objetivo deste estudo foi comparar o torque de inserção (TI), a resistência flexural (RF) e as alterações de superfície em mini-implantes ortodônticos de aço inoxidável (MIs-Ai) e de liga de titânio (MIs-Ti). Métodos: Vinte e quatro MIs (2 x 10 mm; MIs-Ai, n = 12; MIs-Ti, n = 12) foram inseridos em blocos de osso artificial de densidades de 20 lb/ft3 (20 PCF) e 40 lb/ft3 (40 PCF). O torque máximo de inserção foi registrado por meio de um torquímetro digital. A resistência flexural foi avaliada nas deflexões de 2, 3 e 4 mm. Topografia de superfície e composição química dos MIs foram avaliadas por Microscopia Eletrônica de Varredura (MEV) e Espectroscopia de Energia Dispersiva de Raios X (EDS). Modelos lineares gerais e mistos foram utilizados para avaliar o efeito do tipo de MI, da densidade óssea e da deflexão nos desfechos avaliados. Resultados: O TI dos MIs-Ti foi 1,1 Ncm maior do que o obtido para os MIs-Ai (P = 0,018). O TI para MIs inseridos em blocos de teste de 40 PCF foi 5,4 Ncm maior do que para aqueles inseridos em blocos de teste 20 PCF (p < 0,001). MIs-Ai inseridos em osso de maior densidade (40 PCF) apresentaram resistência flexural significativamente maior do que outros grupos, em deflexões de 2 mm (98,7 ± 5,1 Ncm), 3 mm (112,0 ± 3,9 Ncm) e 4 mm (120,0 ± 3,4 Ncm) (p < 0,001). A MEV evidenciou fraturas nos MIs-Ti. A EDS revelou incorporação de 18% de C e 2,06% de O nos MIs-Ai e 3,91% de C nos MIs-Ti, ambos submetidos a testes mecânicos. Conclusões: Com base nos resultados desse estudo in vitro, os MIs-Ai aparentam oferecer adequada estabilidade e maior resistência mecânica, em comparação aos MIs-Ti, quando inseridos em osso de maior densidade.

Changes in the properties of bulk-fill resins under conditions of gastroesophageal reflux and bulimia

Aim: Evaluate the roughness, microhardness and color change of different Bulk Fill resins when submitted to the condition of gastroesophageal reflux and bulimia. Methods: 60 specimens (n = 10) of Bulk-Fill composite resins were made: M1 ­ Filtek™; M2 ­ Tetric N-Ceram and M3 ­ OPUS, through a matrix 2x6 mm and light cured by the VALO light source. After polishing, initial analyzes (48 hours - T0) of surface roughness (Ra), microhardness (VHN) and color change (ΔE) were performed. To simulate the oral condition of severe gastroesophageal reflux and bulimia, the specimens were immersed in hydrochloric acid (S1) (pH 1.7) 4 minutes a day, for 7 days. Control group specimens were immersed in artificial saliva (S2). Subsequently to immersions, mechanical brushing was performed for 3 minutes, three times a day, simulating 7 days of brushing. And again, the analyzes of Ra, VHN and ΔE were performed (7 days - T1). Thus, hydrochloric acid immersion, mechanical brushing and Ra analysis were repeated at 14 days (T2) and 21 days (T3); and T2, T3 and T4 (3 years) for VHN and ΔE. Results: After Shapiro-Wilk statistical test, ANOVA and Tukey test with Bonferroni adjustment (p>0.05), M3 showed the lowest Ra at all times compared to the other resins, while the highest Ra was at T0. M1 and T1 showed higher VHN. And M2 and T4 showed higher ΔE. Conclusion: Bulk Fill resins can be indicated for patients with Gastroesophageal Reflux and Bulimia, nonetheless, Tetric N-Ceram resin showed the worst results

Zircônia na odontologia: mini-revisão / Zirconia in Dentistry: mini-review

Objetivo: O objetivo deste estudo é fornecer ao cirurgião-dentista conhecimento sobre aspectos gerais da zircônia e abordar a introdução das diferentes gerações. Materiais e métodos: Foi realizada uma pesquisa eletrônica da literatura atual em inglês, incluindo artigos científicos publicados até 2019. Resultados: De acordo com os artigos selecionados, diferenças importantes foram encontradas em relação as novas composições da zircônia, sua microestrutura, diferenças no conteúdo da fase cúbica, e de ítria na fase tetragonal, levando a diferentes propriedades ópticas, mecânicas e de resistência ao envelhecimento. Conclusão: A zircônia é o material mais resistente disponível entre as cerâmicas, com diferenças mecânicas e ópticas entre os materiais disponíveis. A introdução das coroas monolíticas resolveu o problema de lascamento da porcelana de cobertura, mas foram necessárias modificações estruturais para fornecer adequada translucidez.

Purpose: This study aims to provide knowledge to clinicians about general aspects of zirconia and to approach the introduction of different zirconia generations. Methods:An electronic search of the English current literature was conducted including scientific articles published up to 2019. Results: According to the selected articles, important differences were found in terms of the novel compositions of zirconia, microstructures among the materials, differences in cubic phase content and yttria in the tetragonal phase, leading to different optical, mechanical and aging resistance properties. Conclusion: Zirconia is the most resistant material available among ceramics with mechanical and optical differences on available materials. The introduction of the monolithic crowns solving the veneering delamination but struc-tural modifications were necessary to provide adequate translucency

Cytotoxicity and Elemental Release of Dental Acrylic Resin Modified with Silver and Vanadium Based Antimicrobial Nanomaterial / Citotoxicidade e Liberação Elementar de Resina Acrílica Odontológica Modificada com Nanomaterial Antimicrobiano a Base de Prata e Vanádio

The acrylic resin used for the prosthesis base accumulates biofilm, causing diseases such as stomatitis. The addition of some nanoparticles promotes antimicrobial action. This study incorporated the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) to the acrylic resin by two methods and evaluated the cytotoxicity for human gingival fibroblasts (HGF) and the released silver and vanadium ions. The concentrations of 0.5, 1, 2.5, and 5% of AgVO3 was incorporated by vacuum spatulation and polymeric film. The vacuum spatulation was performed for 60 s using the Turbomix equipment, and the polymeric film was obtained from the polymer solubilization in chloroform, the film was subjected to a cryogenic grinding, and the powder obtained was manually mixed at the monomer. HGF cell viability was assessed after 24 hours, 7 and 14 days by the MTT assay. The release of silver (Ag) and vanadium (V) ions were quantified by inductively coupled plasma mass spectrometry after 30 days. Kruskal-Wallis and Dunn's test were applied (α = 0.05). The HGF viability was inversely proportional to the incubation time. Both incorporation techniques and the negative and positive control groups presented significant statistical differences (p<0.05). The experimental groups presented no statistical difference compared to the negative control (p>0.05), except the vacuum spatulation group with 5% of AgVO3 that showed greater viability than the negative control (p=0.013) in 24 hours. The release of Ag and V ions was proportional to the concentration of AgVO3 The 5% group presented a significant difference compared to the other groups (p<0.05). In conclusion, the acrylic resin with and without the AgVO3 incorporation had a small cytotoxic potential for HGF in 24 hours, with a lower viability in longer contact times; the release of Ag and V ions was proportional to the concentration of AgVO3, not influencing cell viability. (AU)

A resina acrílica utilizada para a base da prótese acumula biofilme, causando doenças como a estomatite. A adição de algumas nanopartículas promove ação antimicrobiana. Este estudo incorporou o vanadato de prata nanoestruturado decorado com nanopartículas de prata (AgVO3) à resina acrílica por dois métodos e avaliou a citotoxicidade para fibroblastos gengivais humanos (HGF) e os íons prata e vanádio liberados. As concentrações de 0,5%, 1%, 2,5% e 5% de AgVO3 foram incorporadas por espatulação a vácuo e filme polimérico. A espatulação a vácuo foi realizada por 60 s no equipamento Turbomix, e o filme polimérico foi obtido a partir da solubilização do polímero em clorofórmio, o filme foi submetido a uma moagem criogênica e o pó obtido foi misturado manualmente ao monômero. A viabilidade celular de HGF foi avaliada após 24 horas, 7 e 14 dias pelo ensaio de MTT. A liberação de íons prata (Ag) e vanádio (V) foi quantificada por espectrometria de massa com plasma indutivamente acoplado após 30 dias. Os testes de Kruskal-Wallis e Dunn foram aplicados (α=0,05). A viabilidade de HGF foi inversamente proporcional ao tempo de incubação. As técnicas de incorporação e os grupos controle negativo e positivo apresentaram diferença estatisticamente significante (p<0,05). Os grupos experimentais não apresentaram diferença estatística em relação ao controle negativo (p>0,05), exceto o grupo de espatulação a vácuo com 5% de AgVO3 que apresentou maior viabilidade que o controle negativo (p = 0,013) em 24 horas. A liberação de íons Ag e V foi proporcional à concentração de AgVO3. O grupo 5% apresentou diferença significativa em relação aos demais grupos (p <0,05). Em conclusão, a resina acrílica com e sem a incorporação de AgVO3 apresentou um pequeno potencial citotóxico para o HGF em 24 horas, com menor viabilidade nos tempos de maior contato, e a liberação de íons Ag e V foi proporcional à concentração de AgVO3, não influenciando na viabilidade celular. (AU)

Effect of Thermomechanical Fatigue on Shear Strength between a Conventional and an Experimental Polymer for Prosthetic Application / Efeito da Fadiga Termomecânica na Resistência ao Cisalhamento Entre um Polímero Convencional e um Polímero Experimental para Aplicação Protética

The incorporation of antimicrobial agents may influence the mechanical properties of acrylic resins. Thus, the use of these agents only in regions of dental prostheses subject to greater contamination may be an alternative. This study evaluates the effect of thermomechanical fatigue on the bond strength between a conventional and an experimental acrylic resin incorporated with nanostructured silver vanadate decorated with silver nanoparticles (AgVO3). 60 specimens (Ø13mm x 23mm height) in self-curing resin were obtained and divided into groups according to the experimental resin incorporated with AgVO3 (Ø4mm x 6mm height): G1­Conventional x Conventional, G2­Conventional x 2.5% of AgVO3, G3­Conventional x 5% of AgVO3. Ten samples of each group were subjected to bond strength analysis after manufacture, and 10 were previously submitted to 1.200.000 cycles with 98N load and 2Hz/second frequency and alternating baths of 5 ºC, 37ºC and 55 ºC. The fracture area was analyzed. The data were submitted to analysis of variance of two-factors with Bonferroni adjustment for post hoc comparisons (α=0.05) was used. The fatigue did not affect the bond strength (p=0.416), however, there was influence of the AgVO3 concentration on the bond strength between the resins (p=0.013). Mixed failures with adhesive predominance were observed in samples without AgVO3 and cohesive failures in samples with the nanomaterial. The use of AgVO3 can improve or maintain the bond strength between resins with no thermomechanical fatigue influence. (AU).

A incorporação de agentes antimicrobianos pode influenciar nas propriedades mecânicas de resinas acrílicas. Desta forma, o uso destes agentes apenas em regiões das próteses dentárias sujeitas a maior contaminação pode ser uma alternativa. Este estudo avalia o efeito da fadiga termomecânica na resistência de união entre uma resina acrílica convencional e uma experimental incorporada com vanadato de prata nanoestruturado decorado com nanopartículas de prata (AgVO3). Foram obtidos 60 espécimes (Ø13mm x 23mm de altura) em resina autopolimerizável, divididos em grupos de acordo com a resina experimental incorporada com AgVO3 (Ø4mm x 6mm de altura): G1-Convencional x Convencional, G2-Convencional x 2,5% de AgVO3, G3 -Convencional x 5% de AgVO3. Dez amostras de cada grupo foram submetidas à análise de resistência à união após a confecção e 10 foram submetidas previamente a 1.200.000 ciclos com carga de 98 N e frequência de 2Hz/segundo e banhos alternados de 5 ºC, 37 ºC e 55 ºC. A área de fratura foi analisada. Os dados foram submetidos à análise de variância de dois fatores com ajuste de Bonferroni para comparações pos hoc (α = 0,05). A fadiga não afetou a força de união (p=0,416), no entanto, houve influência da concentração de AgVO3 na resistência de união entre as resinas (p=0,013). Falhas mistas com predominância adesiva foram observadas nas amostras sem AgVO3 e falhas coesivas nas amostras contendo o nanomaterial. O uso de AgVO3 pode melhorar ou manter a resistência da união entre as resinas sem influência da fadiga termomecânica.

Influence of an alternative implant design and surgical protocol on primary stability

Abstract The purpose of thisin vitrostudy was to evaluate the influence of a new proposal of implant design and surgical protocol on primary stability in different bone densities. Four groups were tested (n=9): G1 - tapered, cone morse, Ø 4.3 mm x 10 mm in length (Alvim CM); G2 - experimental tapered; G3 - cylindrical, cone morse, Ø 4.0 mm x 11 mm in length (Titamax CM) and G4 - experimental cylindrical. The experimental implants were obtained from a design change in the respective commercial models. The insertion was performed in polyurethane (PU) blocks 0.24 g/cm3(20 pcf) and 0.64 g/cm3(40 pcf), according to different surgical protocols. The primary stability was measured by means of insertion torque (IT) and pullout test. Data were analyzed by ANOVA, Tukey's test (α=0.05) and Pearson's correlation. For IT and pullout, conventional and experimental implants showed no difference between them when inserted in the 20 pcf PU (p>0.05). In the 40 pcf PU, the modified implants exhibited greater IT (p<0.05) and lower pullout (p<0.05) compared to the respective conventional models. The implant design tested associated with the surgical protocol, positively influenced primary stability in higher density bones.

Resumo O objetivo deste estudo in vitro foi avaliar a influência de uma nova proposta de design de implante e protocolo cirúrgico na estabilidade primária em diferentes densidades ósseas. Foram testados quatro grupos (n=9): G1 - cônico, cone morse, Ø 4,3 mm x 10 mm de comprimento (Alvim CM); G2 - experimental cônico; G3 - cilíndrico, cone morse, Ø 4,0 mm x 11 mm de comprimento (Titamax CM) e G4 - experimental cilíndrico. Os implantes experimentais foram obtidos a partir de uma mudança no design dos respectivos modelos comerciais. A inserção foi realizada em blocos de poliuretano (PU) 0,24 g/cm3 (20 pcf) e 0,64 g/cm3 (40 pcf), de acordo com diferentes protocolos cirúrgicos. A estabilidade primária foi aferida por meio do torque de inserção (TI) e ensaio de arrancamento. Os dados foram analisados por ANOVA, teste de Tukey (α=0,05) e correlação de Pearson. Para TI e arrancamento, os implantes convencionais e experimentais não mostraram diferença entre si quando inseridos na PU de 20 pcf (p>0,05). Na PU de 40 pcf, os implantes modificados exibiram maior TI (p <0,05) e menor arrancamento (p <0,05) em relação aos respectivos modelos convencionais. O design do implante testado associado ao protocolo cirúrgico, influenciou positivamente a estabilidade primária em ossos de maior densidade.

Alternative fixation system for implant-retained overdenture: case report / Sistema alternativo de fixação para overdenture implanto-retida: relato de caso

ABSTRACT The aim of this case report was to describe a prosthetic rehabilitation associated with an alternative model of polymer capsule for fixation system of implant-retained overdentures. Patient sought treatment at the clinic of School of Dentistry of Ribeirão Preto, due to lack of retention of their conventional total superior prostheses and inferior overdenture. The initial complaint was clinicallyconfirmed by altered intermaxillary relationships and severe reabsorption of the maxillary crest. In order to restore the function and improve its quality of life, it was proposed a prosthetic solution including implant fixed prosthesis to maxilla and a mandibular overdenture, with ball-type attachments associated with an alternative model of polymer capsule. This treatment was proposed inorder to reestablish the intermaxillary relationships and adequate occlusion, maintain retention and stability of the prosthesis. At the end of treatment and during a one-year follow-up of the case, the patient reported satisfaction and significant improvement in quality of life.

RESUMO O objetivo deste relato de caso foi descrever uma reabilitação protética associada a um modelo alternativo de cápsula polimérica para sistema de fixação de overdentures implantado-retidas. Paciente procurou tratamento na clínica da Faculdade de Odontologia de Ribeirão Preto, devido falta de retenção de suas próteses totais superiores convencionais e overdenture inferior. A queixa inicialfoi clinicamente confirmada por relações intermaxilares alteradas e reabsorção severa da crista maxilar. Para restaurar a função e melhorar sua qualidade de vida, propôs-se como solução protética, a confecção de prótese fixa sobre implantes para a maxila e overdenture mandibular, com acessórios tipo bola associados a um modelo alternativo de cápsula polimérica. Esse tratamento foiproposto a fim de restabelecer as relações intermaxilares e a oclusão adequada, manter a retenção e a estabilidade da prótese. Ao final do tratamento e durante o acompanhamento de um ano do caso, o paciente relatou satisfação e melhora significativa na qualidade de vida.

Prótese de Transição x Prótese sobre Implantes: Relato de Caso / Transitional Prosthesis x Implant-Supported Prosthesis: Case Report

Objetivo: O objetivo desse trabalho foi descrever um caso clínico, realizado na Faculdade de Odontologia de Ribeirão Preto ­ Universidade de São Paulo, com adaptação da prótese parcial removível do paciente em prótese total provisória de transição, após a instalação de implantes odontológicos. Material e método: O paciente era usuário de prótese parcial removível associada à prótese parcial fixa inferior, cujos pilares eram os elementos 42 e 44. Ambos os dentes apresentavam indicação para extração. Após a remoção da prótese fixa e extração dos dentes 42 e 44, foram instalados quatro implantes na região anterior da mandíbula, e confeccionada uma prótese total de transição, a partir da prótese parcial removível do paciente. Após o período de osseointegração, a prótese sobre implantes definitiva foi confeccionada. Conclusão: A adaptação de prótese parcial removível em prótese total provisória de transição reduz o tempo dos procedimentos clínicos e o custo do tratamento, permitindo ao paciente a manutenção de suas funções orais, até a confecção da prótese definitiva.

Objective: The aim of this study was to describe a case, performed at the Dental School of Ribeirão Preto - University of São Paulo, with adaptation of the removable partial denture of the patient in a transitional denture after the installation of dental implants. Material and Methods: Patient was a user of a mandibular removable partial denture associated with fixed partial dentures, whose pillars were teeth 42 and 44, both indicated for extraction. After removal of the fixed partial dentures and extraction of 42 and 44, four implants were installed in the anterior region of the mandible, and a transitional denture was made from the patient's removable partial denture. After the period of osseointegration, the definitive implant prosthesis was made. Conclusions: The adaptation of a removable partial denture in a transitional denture reduces the time of the clinical procedures and the cost of the treatment, allowing to the patient to maintain his/her oral functions, until the definitive implant prosthesis is made.

Bond strength of resin cements to novel materials to intracanal posts applications / Resistência de união de cimentos resinosos a novos materiais para pinos intrarradiculares

Objective: Evaluate the bond strength of resin cements to new materials for application in intraradicular posts. Material and Methods: Five materials were evaluated: fiberglass, PET, polyethylene, polyacetal and PTFE. Two commercial resin cements (Rely X U200 and Rely X Arc) were applied on the test specimens of the materials (9x3mm) and the bonding was evaluated through the shear bond strength test, where the chisel operated with a load of 1kN and a velocity of 0.5mm/min at the cement/material interface. The data were analyzed by the Shapiro-Wilk test, followed by the two-way analysis of variance, performed with the Bonferroni post-test (α=0.05). Results: The glass fiber was statistically different from all evaluated materials (p0.05). Comparing the two cements, a statistical difference was found between Rely X U200 and Arc only for the glass fiber (p=0). Conclusion: PET, polyethylene, polyacetal and PTFE exhibited reduced bond strength compared to the glass fiber (AU)

Objetivo: Avaliar a resistência de união de cimentos resinosos a novos materiais para aplicação em pinos intrarradiculares. Material e método: Foram avaliados cinco materiais: fibra de vidro, PET, polietileno, poliacetal e PTFE. Dois cimentos resinosos comerciais (Rely X U200 e Rely X Arc) foram aplicados sobre os corpos de prova dos materias (9x3mm) e a resistência de união foi avaliada através do teste de cisalhamento, onde o cinzel atuou com carga de 1kN e velocidade de 0,5mm/min na interface cimento/material. Verificada a normalidade dos dados através do teste Shapiro-Wilk, foi realizada a análise de variância de dois fatores com pós-teste de Bonferroni (α=0,05). Resultados: a fibra de vidro foi diferente estatisticamtente de todos os materiais avaliados (p0,05). Comparando-se os dois cimentos, foi encontrada diferença estatística entre o Rely X U200 e Arc apenas para a fibra de vidro (p=0). Conclusão: PET, polietileno, poliacetal e PTFE apresentaram resistência de união reduzida comparando-se à fibra de vidro. (AU)

In Vitro Microstructural Analysis of Dental Implants Subjected to Insertion Torque and Pullout Test

The change in the implant microstructure during handling may reduce the potential of surface treatment on the osteoinduction and, therefore, on the osseointegration. The aim of this study was to evaluate by energy-dispersive X-ray spectroscopy (EDX) the effect of insertion torque and pullout test on the microstructure of dental implants with different shapes. Four shapes of implants (n=8) were selected: conical with surface treatment (COTS), cylindrical with surface treatment (CTS), cylindrical with double surface treatment (CTSD) and cylindrical with machined surface (CSU). Before and after performing the mechanical tests, the screw surfaces were subjected to analysis of chemical composition by EDX. The results obtained by the microstructural analysis showed presence of three main chemical elements: Ti, C and O. There was a significant change in the concentration of Ti and C. The implant with double surface treatment (CTSD) showed the greatest Ti reduction and the greatest C increase. It may be concluded that the mechanical manipulation may alter the implant surfaces as regards their microstructure. Therefore, surgical planning should take into consideration the choice of surface treatment because the characteristics of the implants may be modified as they are inserted and removed from the bone site.

A alteração da microestrutura do implante durante seu manuseio pode reduzir o potencial do tratamento superfícial na osteoindução e consequentemente na osseointegração. O objetivo deste estudo foi avaliar o efeito do torque de inserção e do ensaio de arrancamento, na microestrutura de implantes odontológicos de diferentes formatos, por meio de espectometria de energia dispersiva de raios-X (EDS). Para a realização do estudo foram selecionados quatro modelos de implantes Conexão(r) (n=8): Cônico com tratamento de superfície (COTS), Cilíndrico com tratamento de superfície (CTS), Cilíndrico com duplo tratamento de superfície (CTSD) e Cilíndrico com superfície usinada (CSU). Antes e após a realização dos ensaios mecânicos, os parafusos foram submetidos à análise da composição química de suas superfícies, por meio de EDS. Os resultados obtidos com a análise microestrutural demonstraram a presença de três elementos químicos principais: Ti, C e O. Foi verificada alteração estatisticamente significante na concentração dos elementos Ti e C. O implante com duplo tratamento de superfície (CTSD) foi o que apresentou a maior redução do Ti e maior aumento do C. A partir dos dados obtidos foi possível concluir que a manipulação mecânica pode alterar a superfície dos implantes quanto à sua microestrutura. Sendo assim, o planejamento cirúrgico deve levar em conta a escolha do tratamento de superfície, pois uma vez que o implante é inserido e removido do leito ósseo suas características podem ser alteradas.

Surface treatment of implants: primary stability / Tratamento de superfície de implantes: frequência de ressonância

OBJECTIVE: The aim of this study was to analyze the primary stability of dental implants with and without surface treatment, by means of resonance frequency, using different materials as substitutes for human bone substrates for insertion. METHODS: Sixteen external hexagon, cylindrical Conexão(r) titanium implants were used, 11.5 mm long by 3.75 mm wide, as follows: 8 Master Porous (MP), with surface treatment and 8 Master Screw (MS) machined. The implant placement was performed on the following substrates: pork rib bone, wood, artificial bone polyurethane National(r) (40, 20, 15 PCF) and Synbone(r). Primary stability was assessed via resonance frequency using an Osstell Mentor(tm) device. Data were analyzed statistically using ANOVA and Tukey's test, with a significance level of 5%. RESULTS: It was found that although MP and MS have a higher value on all substrates, these were not statistically different between groups (p>0.05), except for polyurethane National(r) 20 PCF. When inserted into the wood substrate and polyurethane National(r) 40 PCF, MP and MS had higher values​​. MP, when inserted into the pig bone, was also statistically equal to these interactions. CONCLUSION: Despite the continuous development of innovations in the characteristics of implant surfaces to assist with the performance of osseointegrated implants, and the fact that our study has found that the surface treatment had no impact on the primary stability checked using ressonance frequency, there is still very little scientific understanding of these effects. .

OBJETIVO: Analisar a estabilidade primária de implantes odontológicos com tratamento e sem tratamento de superfície, por meio da frequência de ressonância, utilizando diferentes materiais como substratos substitutos do osso humano para sua inserção. MÉTODOS: Foram utilizados 16 implantes de titânio Conexão(r), cilíndricos, hexágono externo, com 11,5 mm de comprimento e 3,75 mm de largura, sendo: 8 Master Porous, com tratamento de superfície; e 8 Master Screw, usinados. A instalação de implantes foi realizada nos seguintes substratos: osso de costela suína, madeira, osso artificial de poliuretana da marca Nacional(r) (40, 20 e 15 PCF) e da marca Synbone(r). Foi avaliada a estabilidade primária através da frequência de ressonância utilizando o aparelho Osstell(tm) Mentor. Os dados obtidos foram submetidos a tratamento estatístico ANOVA e Teste de Tukey, com nível de significância a 5%. RESULTADOS: Foi constatado que, apesar de Master Porous apresentar maior valor que Master Screw em todos os substratos, estes não apresentaram diferença estatística entre si (p>0,05), com exceção da poliuretana Nacional(r) de 20 PCF. Quando inseridos no substrato madeira e na poliuretana Nacional(r) 40 PCF, Master Porous e Master Screw tiveram maiores valores. Master Porous, quando inserido no osso suíno também foram iguais estatisticamente a estas interações. CONCLUSÃO: Apesar de inovações nas características das superfícies de implantes serem desenvolvidas constantemente para contribuir no desempenho de implantes osseointegrados, e nosso estudo encontrar que não houve influência do tratamento de superfície na estabilidade primária aferida por frequência de ressonância; ainda há pouco conhecimento científico sobre esses efeitos. .

Development of a novel resin with antimicrobial properties for dental application

The adhesion of biofilm on dental prostheses is a prerequisite for the occurrence of oral diseases. Objective: To assess the antimicrobial activity and the mechanical properties of an acrylic resin embedded with nanostructured silver vanadate (β-AgVO3). Material and Methods: The minimum inhibitory concentration (MIC) of β-AgVO3 was studied in relation to the species Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231. The halo zone of inhibition method was performed in triplicate to determine the inhibitory effect of the modified self-curing acrylic resin Dencor Lay - Clássico®. The surface hardness and compressive strength were examined. The specimens were prepared according to the percentage of β-AgVO3 (0%-control, 0.5%, 1%, 2.5%, 5%, and 10%), with a sample size of 9x2 mm for surface hardness and antimicrobial activity tests, and 8x4 mm for the compression test. The values of the microbiologic analysis were compared and evaluated using the Kruskal-Wallis test (α=0.05); the mechanical analysis used the Shapiro-Wilk's tests, Levene's test, ANOVA (one-way), and Tukey's test (α=0.05). Results: The addition of 10% β-AgVO3 promoted antimicrobial activity against all strains. The antimicrobial effect was observed at a minimum concentration of 1% for P. aeruginosa, 2.5% for S. aureus, 5% for C. albicans, and 10% for S. mutans. Surface hardness and compressive strength increased significantly with the addition of 0.5% β-AgVO3 (p<0.05). Higher rates of the nanomaterial did not alter the mechanical properties of the resin in comparison with the control group (p>0.05). Conclusions: The incorporation of β-AgVO3 has the potential to promote antimicrobial activity in the acrylic resin. At reduced rates, it improves the mechanical properties, and, at higher rates, it does not promote changes in the control. .

Effect of implant design and bone density in primary stability

AIM: To evaluate the influence of the format and surface treatment of implants, as well as the substrate used in primary stability. METHODS: Thirty-two Conexão® implants were used: 8 conical (CC) (11.5 x 3.5 mm) and 24 cylindrical (11.5 x 3.75 mm) - 8 external hexagon implants without surface treatment (MS), 8 external hexagon implants with double Porous treatment (MP), 8 internal hexagon implants with Porous treatment (CA). They were inserted in Nacional® polyurethane in three densities (15, 20 and 40 PCF). The insertion torque (IT) (N.cm) was quantified using the digital Mackena® torque meter, and the pullout force (PF) (N) by means of axial traction force with a 200 kg load cell, performed in a Universal Test Machine (Emic® DL10000) and the Tesc 3.13 software. Data were analyzed statistically by ANOVA and Tukey's test with a significance level of 5%. RESULTS: Difference was observed between groups (p<0.05). Regarding the IT, MP and MS inserted to the substrate 40PCF showed higher values with statistically significant difference with all interactions implants x substrate; the 15 and 20PCF densities was not significant in all groups of implants. MP, MS, CC and CA did not differ significantly, even inserted in a lower density, where CC showed better IT compared with other densities. For PF, the best performance was the interaction implant CA x 40PCF substrate, showing a difference from the other implants inserted in all substrates. CONCLUSIONS: The higher bone density and cylindrical implants with surface treatment provides greater IT and PF.

Estudo in vitro da influência do formato e do tratamento de superfície de implantes odontológicos no torque de inserção, resistência ao arrancamento e frequência de ressonância / In vitro study of the influence of the shape and surface treatment of dental implants in insertion torque, pullout resistance and resonance frequency

Objetivo: A proposta do estudo foi avaliar a influência do formato e do tratamento de superfície na estabilidade primária de implantes odontológicos, inseridos em diferentes substratos, utilizando-se associação de métodos, como torque de inserção, resistência ao arrancamento e frequência de ressonância. Material e Método: Foram utilizados 32 implantes da marca Conexão® (Conexão Sistemas de Prótese Ltda, Arujá, São Paulo, Brasil), sendo: oito cilíndricos com tratamento Porous (CA), oito cilíndricos usinados (MS), oito cilíndricos tratamento duplo Porous (MP) e oito cônicos sem tratamento (CC). Os substratos utilizados para inserção foram: costela de porco; poliuretana Synbone©; poliuretana Nacional® (15, 20, 40 PCF), e madeira. O torque de inserção (TI) foi quantificado utilizando-se um torquímetro digital Kratos®; a força de arrancamento (RA) foi aferida por meio de tração axial, realizada em uma Máquina Universal de Ensaios (Emic® DL-10000), e utilizou-se também análise por meio de frequência de ressonância (RF). Para obtenção dos resultados estatísticos, utilizou-se análise de variância e teste de Tukey (significância de 5%). Resultado: Ao analisar o torque de inserção, verificou-se que os implantes com tratamento de superfície não foram diferentes estatisticamente dos usinados, assim como os implantes cilíndricos não tiveram diferença dos cônicos em todos os substratos (p>0,05), com exceção da poliuretana Synbone©. Em relação à resistência ao arrancamento, os implantes tratados e usinados, assim como cônicos e cilíndricos, não tiveram diferença estatística (p>0,05); a análise de frequência de ressonância mostrou que não houve diferença entre os implantes (p>0,05), com exceção da poliuretana Nacional® (20 PCF). Conclusão: Os formatos e o tratamento de superfície estudados não demonstraram valores significantes quando foram comparados os implantes entre si e, considerando os substratos avaliados, não houve diferença estatística entre os diferentes tipos de implantes.

Objective: The purpose of the study was to evaluate the influence of the shape and surface treatment on the primary stability of dental implants inserted in different substrates through association methods such as insertion torque, pullout strength and resonance frequency. Material and Method: 32 implants were used with 8 cylindrical treatment Porous (CA), 8 machined cylindrical (MS), 8 cylinder dual treatment Porous (MP) and 8 tapered untreated (CC). The substrates used for inclusion were: pork rib; © Synbone polyurethane, polyurethane National ® (15, 20, 40 PCF) and wood. The insertion torque (TI) was quantified using a digital torque Kratos® wrench, the pullout strength (RA) was measured by means of axial traction performed in an Emic DL-10000® and analysis was also used by the resonance frequency (RF). To obtain the statistical results, we used analysis of variance and Tukey's test (5% significance). Result: To analyze the insertion torque, it was found that implants with surface treatment were not statistically different from machined as well as the cylindrical implants did not differ from tapered on all substrates (p>0.05), except © Synbone of polyurethane; in relation to RA, treated and machined implants as well as tapered and cylindrical, showed no statistical difference (p>0.05); FR analysis showed no difference between implants (p>0,05), with the exception of National® polyurethane (20 PCF). Conclusion: formats and surface treatment studied showed no significant values when compared implants together and considering the tested substrates showed no statistical difference between the different types of implants.

Microstructure and Mechanical Properties of Composite Resins Subjected to Accelerated Artificial Aging

The aim of this study was to investigate the influence of accelerated artificial aging (AAA) on the microstructure and mechanical properties of the Filtek Z250, Filtek Supreme, 4 Seasons, Herculite, P60, Tetric Ceram, Charisma and Filtek Z100. composite resins. The composites were characterized by Fourier-transform Infrared spectroscopy (FTIR) and thermal analyses (Differential Scanning Calorimetry - DSC and Thermogravimetry - TG). The microstructure of the materials was examined by scanning electron microscopy. Surface hardness and compressive strength data of the resins were recorded and the mean values were analyzed statistically by ANOVA and Tukey's test (α=0.05). The results showed significant differences among the commercial brands for surface hardness (F=86.74, p<0.0001) and compressive strength (F=40.31, p<0.0001), but AAA did not affect the properties (surface hardness: F=0.39, p=0.53; compressive strength: F=2.82, p=0.09) of any of the composite resins. FTIR, DSC and TG analyses showed that resin polymerization was complete, and there were no differences between the spectra and thermal curve profiles of the materials obtained before and after AAA. TG confirmed the absence of volatile compounds and evidenced good thermal stability up to 200 °C, and similar amounts of residues were found in all resins evaluated before and after AAA. The AAA treatment did not significantly affect resin surface. Therefore, regardless of the resin brand, AAA did not influence the microstructure or the mechanical properties.

A influência do sistema de envelhecimento artificial acelerado (EAA) na microestrutura e nas propriedades mecânicas das resinas compostas Z250, Filtek Supreme, 4 Seasons, Herculite, P60, Tetric Ceram, Charisma e Filtek Z100 foi investigada. Os compósitos foram caracterizados por espectroscopia de infravermelho com transformada de Fourier (FTIR) e análises térmicas (calorimetria exploratória diferencial - DSC e termogravimetria - TG). A microestrutura dos materiais foi analisada por microscopia eletrônica de varredura. Os dados de dureza superficial e resistência à compressão foram registados para as resinas e os valores médios foram submetidos ao teste de Kolmogorov-Smirnov (p>0,05), ANOVA e teste de Tukey (α=0,05). Os resultados mostraram diferenças significativas entre as marcas comerciais em termos de dureza (F=86,74, p<0,0001) e resistência à compressão (F=40,31, p<0,0001), mas o EAA não afetou as propriedades (dureza superficial: F=0,39, p=0,53, resistência à compressão: F=2,82, p=0,09) de qualquer uma das resinas. FTIR, DSC e análise de TG revelou que a polimerização da resina foi completa, e não houve diferenças entre os espectros e os perfis de curva térmica dos materiais obtidos, antes e depois de EAA. TG mostrou a ausência de compostos voláteis e evidenciou uma boa estabilidade térmica até 200 °C, e quantidades similares de resíduos foram encontradas em todas as resinas avaliadas, antes e depois de EAA. O tratamento de EAA não afetou significativamente a superfície das resinas. Portanto, independentemente do tipo de resina, o EAA não influenciou a microestrutura e as propriedades mecânicas.

In vitro analysis of the influence of surface treatment of dental implants on primary stability

Surface treatment interferes with the primary stability of dental implants because it promotes a chemical and micromorphological change on the surface and thus stimulates osseointegration. This study aimed to evaluate the effects of different surface treatments on primary stability by analyzing insertion torque (IT) and pullout force (PF). Eight samples of implants with different surface treatments (TS - external hexagon with acid surface treatment; and MS - external hexagon, machined surface), all 3.75 mm in diameter X 11.5 mm in length, were inserted into segments of artificial bones. The IT of each sample was measured by an electronic torquemeter, and then the pullout test was done with a universal testing machine. The results were subjected to ANOVA (p < 0.05), followed by Tukey's test (p < 0.05). The IT results showed no statistically significant difference, since the sizes of the implants used were very similar, and the bone used was not highly resistant. The PF values (N) were, respectively, TS = 403.75 ± 189.80 and MS = 276.38 ± 110.05. The implants were shown to be different in terms of the variables of maximum force (F = 4.401, p = 0.0120), elasticity in maximum flexion (F = 3.672, p = 0.024), and relative stiffness (F = 4.60, p = 0.01). In this study, external hexagonal implants with acid surface treatment showed the highest values of pullout strength and better stability, which provide greater indication for their use.

Influência do formato do implante para reabilitação de casos com limitação de espaço mesiodistal / Influence of the format of the implant on rehabilitation in cases of mesio-distal space limitation

Apesar do grande desenvolvimento da implantodontia, seu sucesso depende de um planejamento rigoroso e em casos com limitação de espaço mesiodistal a seleção do formato do implante é muito importante. Objetivo e relato do caso clínico: Este artigo relata o caso clínico de um paciente com agenesia bilateral dos incisivos laterais superiores e ausência de espaço satisfatório no sentido mesiodistal, impedindo a utilização de implantes em proporções convencionais, apesar de ter realizado um tratamento ortodôntico prévio. Após a realização de exames radiográficos e estudo de modelos articulados em articulador semiajustável, optou-se pela realização de dois implantes de corpo único com carga imediata, da marca SIN®-Unident, de diâmetro reduzido para a solução do caso. Considerações finais: O correto planejamento, diagnóstico e execução da técnica apresentou resultado satisfatório imediato e a longo prazo.