Influence of incorporation of nanostructured silver vanadate decorated with silver nanoparticles on roughness, microhardness, and color change of pit and fissure sealants.

Objective: The aim of this study was to evaluate the roughness, hardness, and color change of pit and fissure sealants of two commercial brands (Fluroshield ™ and Ultraseal XT ™) incorporated with nanostructured silver vanadate nanomaterial decorated with silver nanoparticles (ß-AgVO3) in concentrations (0% - control, 2.5% and 5%). Material and methods: Two commercial brands Fluroshield TM and Ultraseal XT ™ were used to make the samples with dimensions of 6 × 6 × 4 mm. The control group was made according to the manufacturer's instructions and in the groups with the addition of ß-AgVO3, the nanomaterial was added proportionally by mass at percentages of 2.5% and 5%. Roughness properties were evaluated using a 3D Laser Confocal Microscope (n = 10), Knoop microhardness by Microdurometer (n = 10), and color change by Portable Color Spectrophotometer on the CIEDE2000 system (n = 10). Data were evaluated by one-way ANOVA with Bonferroni adjustment and Tukey's mean comparison test at a 5% significance level. Results: Ultraseal XT ™ sealant roughness showed a significant difference between concentrations with the highest mean for the 5% group (P = 0.010). Regarding the hardness, both sealants showed no significant difference between the groups. Fluroshield ™ sealant showed a significant difference in ΔE00 between the control-2.5% 24.93 (3.49) and control-5% 28.41 (2.58). Conclusion: It may be concluded that the incorporation of ß-AgVO3 influenced the increase in roughness for Ultraseal XT ™ pit and fissure sealant, did not interfere with the microhardness of both sealants, and promoted a change in the color of Fluroshield ™ sealant within clinically acceptable limits.

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 3M 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.

Effects of LED Lights on Bulk Fill Resin Polymerization

The present study analyzed the microhardness and degree of conversion of three Bulk Fill resins (M1 - Filtek Bulk Fill; M2 - Tetric N-Ceram Bulk Fill and M3 - Opus Bulk Fill) polymerized by single peak and polywave Light-emitting Diode Curing Lights. A total 90 test specimens (n=10) were obtained using a Teflon matrix for the purpose of testing microhardness; and for degree of conversion: 135 specimens (n=5) by using a 2 x 6 cm matrix. The specimens were light polymerized using 3 light sources (L1 - Optilight Max, L2 - Bluephase, L3 - VALO). They were kept in artificial saliva om an oven at 37±1°C during the experiment. The degree of conversion was measured by FTIR 24 h after obtaining each test specimen. The microhardness readouts were performed with a microdurometer at the time intervals of 48 hours (T0), 7 days (T1), 14 days (T2) and 21 days (T3). M1L3 was found to show the highest microhardness values in T2, and M1 showed the lowest degree of conversion in the deep third with L1. It was concluded that Filtek Bulk Fill resin showed the best results in comparison with the other resins.

El presente estudio analizó la microdureza y el grado de conversión de tres resinas Bulk Fill (M1 - Filtek Bulk Fill; M2 - Tetric N-Ceram Bulk Fill y M3 - Opus Bulk Fill) polimerizadas por lámparas de curado de diodo emisor de luz de pico único y polionda. Se obtuvieron un total de 90 especímenes de prueba (n=10) utilizando una matriz de teflón con el propósito de probar la microdureza; y para grado de conversión: 135 especímenes (n=5) utilizando una matriz de 2 x 6 cm. Las muestras se fotopolimerizaron utilizando 3 fuen- tes de luz (L1 - Optilight Max, L2 - Bluephase, L3 - VALO). Se mantuvieron en saliva artificial en estufa a 37 ±1°C durante el experimento. El grado de conversión se midió por FTIR 24 h después de obtener cada muestra de prueba. Las lecturas de microdureza se realizaron con un microdurómetro en los intervalos de tiempo de 48 horas (T0), 7 días (T1), 14 días (T2) y 21 días (T3). Se encontró que M1L3 mostraba los valores más altos de microdureza en T2, y M1 mostraba el grado más bajo de conversión en el tercio profundo con L1. Se concluyó que la resina Filtek Bulk Fill mostró los mejores resultados en comparación con las demás resinas.

Osseointegration in additive-manufactured titanium implants: A systematic review of animal studies on the need for surface treatment.

The objective of the systematic review is to find an answer to a question: "Do surface treatments on titanium implants produced by additive manufacturing improve osseointegration, compared to untreated surfaces?". This review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA 2020) and was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022321351). Searches were performed in PubMed, Scopus, Science Direct, Embase, and Google Scholar databases on March 22nd, 2022. Articles were chosen in 2 steps by 2 blinded reviewers based on previously selected inclusion criteria: articles in animals that addressed the influence of surface treatments on osseointegration in implants produced by additive manufacturing. Articles were excluded that (1) did not use titanium surface, 2) that did not evaluate surface treatments, 3) that did not described osseointegration, 4) Studies with only in vitro analyses, clinical studies, systematic reviews, book chapters, short communications, conference abstracts, case reports and personal opinions.). 1003 articles were found and, after applying the eligibility criteria, 17 were used for the construction of this review. All included studies found positive osseointegration results from performing surface treatments on titanium. The risk of bias was analyzed using the SYRCLE assessment tool. Surface treatments are proposed to promote changes in the microstructure and composition of the implant surface to favor the adhesion of bone cells responsible for osseointegration. It is observed that despite the benefits generated by the additive manufacturing process in the microstructure of the implant surface, surface treatments are still indispensable, as they can promote more suitable characteristics for bone-implant integration. It can be concluded that the surface treatments evaluated in this systematic review, performed on implants produced by additive manufacturing, optimize osseointegration, as it allows the creation of a micro-nano-textured structure that makes the surface more hydrophilic and allows better contact bone-implant.

Bacterial Adhesion Strength on Titanium Surfaces Quantified by Atomic Force Microscopy: A Systematic Review.

Few studies have been able to elucidate the correlation of factors determining the strength of interaction between bacterial cells and substrate at the molecular level. The aim was to answer the following question: What biophysical factors should be considered when analyzing the bacterial adhesion strength on titanium surfaces and its alloys for implants quantified by atomic force microscopy? This review followed PRISMA. The search strategy was applied in four databases. The selection process was carried out in two stages. The risk of bias was analyzed. One thousand four hundred sixty-three articles were found. After removing the duplicates, 1126 were screened by title and abstract, of which 57 were selected for full reading and 5 were included; 3 had a low risk of bias and 2 moderated risks of bias. (1) The current literature shows the preference of bacteria to adhere to surfaces of the same hydrophilicity. However, this fact was contradicted by this systematic review, which demonstrated that hydrophobic bacteria developed hydrogen bonds and adhered to hydrophilic surfaces; (2) the application of surface treatments that induce the reduction of areas favorable for bacterial adhesion interfere more in the formation of biofilm than surface roughness; and (3) bacterial colonization should be evaluated in time-dependent studies as they develop adaptation mechanisms, related to time, which are obscure in this review.

Effect of pores on cell adhesion to additively manufactured titanium implants: A systematic review.

STATEMENT OF PROBLEM: Titanium dental implants produced by additive manufacturing have pores that, depending on their size and quantity, may improve osteogenic cell adhesion without impairing mechanical properties. A systematic review of in vitro studies on this topic is lacking. PURPOSE: The purpose of this systematic review was to answer the question "What is the influence of pores on osteogenic cell adhesion on titanium surfaces produced by additive manufacturing?". MATERIAL AND METHODS: The study was designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 standards and registered in the Open Science Framework (OSF) (osf.io/baw59). A manual search of published articles without language or time restrictions was conducted in November 2022 in the electronic databases PubMed, Scopus, ScienceDirect, Embase, and in the nonpeer-reviewed literature via Google Scholar. RESULTS: A total of 1338 initial results were found, and after removing duplicates and applying eligibility criteria, 13 articles were included in this review that, according to the Joanna Briggs Institute (JBI) tool, presented a low risk of bias. Pores with larger diameters provide greater a surface area that favors cell filopodia adhesion and has interconnection that optimizes the transport of nutrients and oxygen and bone cell activity. CONCLUSIONS: The presence of pores on the surface of titanium produced by additive manufacturing increases the adhesion, migration, proliferation, and viability of osteogenic cells.

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

Influence of ß-AgVO3 nanomaterial incorporation on mechanical and microbiological properties of dental porcelain.

OBJECTIVE: To explore the effect of adding different percentages of nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3) to dental porcelains, evaluating the antimicrobial activity and the influence on the mechanical properties. METHODS: Thirty-six specimens were made, for each concentration, control group, 0.5%, 1%, 2.5% and 5%, using two commercial brands: IPS InLine and Noritake Cerabien ZR. For the analysis of mechanical properties, the Vickers microhardness test and the roughness test were performed. For the antimicrobial analysis, the XTT and CFU assays were performed. RESULTS: There was a statistically significant difference between groups for mechanical and microbiological analyses. SIGNIFICANCE: The modification of dental porcelains, with the incorporation of ß-AgVO3, influenced the mechanical properties of the material and demonstrated antimicrobial activity at certain concentrations.

Protein absorption on titanium surfaces treated with a high-power laser: A systematic review.

STATEMENT OF PROBLEM: The surface of titanium dental implants treated with a high-power laser has been reported to favor osseointegration, mainly by altering protein uptake. Despite the large number of articles that address the topic, the heterogeneity of methodologies and results makes an understanding of the treatment's benefits difficult, and a systematic review is needed. PURPOSE: The purpose of this systematic review was to further the knowledge on protein uptake on titanium surfaces that have undergone treatment with a high-power laser. MATERIAL AND METHODS: This review followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines and was registered with the Open Science Framework (OSF) (osf.io/gcbna). Searches were performed in PubMed, Scopus, Web of Science, Embase, and Google Scholar databases. The articles were selected in 2 steps by 2 independent reviewers according to the previously selected eligibility criteria. The risk of bias was analyzed by using the Joanna Briggs Institute (JBI)-adapted quasi-experimental study evaluation tool. RESULTS: The studies addressed have shown that applying a high-power laser to the implant surface, depending on its settings, generates topographical changes that can optimize the protein absorption process and thus accelerate the other biological processes. CONCLUSIONS: The studies identified in this systematic review showed that surface treatment with a high-power laser represents a promising technique with a positive influence on protein uptake and osseointegration.

Relationship between temporomandibular dysfunctions, sleep disorders, and anxiety among dentistry students.

Introduction: This study aimed to evaluate the relationship between temporomandibular dysfunction (TMD), anxiety, and sleep disorder (DS) among dentistry students, relating the periods in which they are enrolled.Methods: The study consisted of 90 students: Group 1: 30 first-period students; Group 2: 30 fifth-period students; Group 3: 30 students from the ninth period. The participants responded to the RDC/TMD, Fletcher & Luckett questionnaires, and the Beck Anxiety Inventory to analyze symptoms of TMD, DS, and anxiety.Results: There was an association between TMD, DS, and the period studied. When related to moderate and severe anxiety, the group that had the highest incidence was Group 1 (first period students).Conclusion: The apprehension for what is new can influence the TMD and DS indices, while the greater concern for academic/professional performance can generate higher levels of anxiety.

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.

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.

Influence of an Alternative Implant Design and Surgical Protocol on Primary Stability.

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.

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.

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)

Relationship between the surface chemical composition of implants and contact with the substrate.

The purpose of the study was to use scanning electron microscopy and energy dispersive x-ray spectrometry to assess possible morphologic and chemical changes after performing double-insertion and pullout tests of implants of different shapes and surface treatments. Four different types of implants were used-cylindrical machined-surface implants, cylindrical double-surface-treated porous implants, cylindrical surface-treated porous implants, and tapered surface-treated porous implants-representing a total of 32 screws. The implants were inserted into synthetic bone femurs, totaling 8 samples, before performing each insertion with standardized torque. After each pullout the implants were analyzed by scanning electron microscopy and energy dispersive x-ray spectrometry using a universal testing machine and magnified 35 times. No structural changes were detected on morphological surface characterization, only substrate accumulation. As for composition, there were concentration differences in the titanium, oxygen, and carbon elements. Implants with surface acid treatment undergo greater superficial changes in chemical composition than machined implants, that is, the greater the contact area of the implant with the substrate, the greater the oxide layer change. In addition, prior manipulation can alter the chemical composition of implants, typically to a greater degree in surface-treated implants.

Development of a novel resin with antimicrobial properties for dental application.

UNLABELLED: 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 (ß-AgVO3). MATERIAL AND METHODS: The minimum inhibitory concentration (MIC) of ß-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 ß-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% ß-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% ß-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 ß-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.