Formación de biopelícula bacteriana sobre las superficies de pilares de cicatrización de PEEK y titanio

Objetivos. Explorar el efecto de las características de superficie sobre el volumen total y la viabilidad de la biopelícula formada sobre pilares de cicatrización de PEEK y titanio. Métodos. Los parámetros de rugosidad (S a y S k) y la energía superficial de pilares de cicatrización de PEEK y titanio (n=3) fueron determinados mediante microscopía confocal láser de barrido (CLSM) y ángulo de contacto, respectivamente. Se determinó luego el volumen total y la viabilidad de una biopelícula bacteriana multiespecie cultivada por 30 días, mediante CLSM y el reactivo LIVE/DEAD Kit BacLight. El tamaño del efecto se determinó mediante d de Cohen. Resultados. Los pilares de PEEK mostraron una mayor rugosidad que los de titanio (S a 0,41 µm vs 0,17 µm), pero no se observaron diferencias en la energía superficial. Si bien el volumen total de biopelícula fue mayor en titanio que en PEEK (696 µm3 vs 419 µm3), no hubo diferencias en la proporción de bacterias vivas entre ambos materiales. Conclusiones. La viabilidad de la biopelícula bacteriana formada no guarda relación directa con las características superficiales de pilares de cicatrización de PEEK y titanio.

Objetivo. Explorar o efeito das características da superfície no volume total e viabilidade do biofilme formado em PEEK e pilares de cicatrização de titânio. Métodos. Parâmetros de rugosidade (S a e S k) e energia de superfície de PEEK e pilares de titânio (n = 3) foram determinados por microscopia confocal de varredura a laser (CLSM) e ângulo de contato, respectivamente. O volume total e a viabilidade de um biofilme bacteriano multiespécie cultivado por 30 dias foram então determinados usando CLSM e o reagente LIVE/DEAD Kit BacLight. O tamanho do efeito foi determinado usando o d de Cohen. Resultados. Os pilares de PEEK mostraram maior rugosidade do que os de titânio (S a 0,41 µm vs 0,17 µm), mas não foram observadas diferenças na energia de superfície. Embora o volume total de biofilme tenha sido maior no titânio do que no PEEK (696 µm3 vs 419 µm3), não houve diferenças na proporção de bactérias vivas entre os dois materiais. Conclusões. A viabilidade do biofilme bacteriano formado não está diretamente relacionada às características da superfície dos pilares de cicatrização de PEEK e titânio.

Objectives . To explore the effect of surface characteristics on the total volume and viability of a bacterial biofilm developed on the surface of PEEK and titanium healing abutments. Methods. Surface parameters S a and S k, as well as the surface energy of PEEK and titanium healing abutments (n=3) were determined using confocal laser scanning microscopy (CLSM) and contact angle, respectively. The total volume and viability of a multispecies bacterial biofilm cultivated for 30 days were determined using CLSM and the LIVE/DEAD BacLight reactive kit. Effect size was determined using Cohen's d. Results. PEEK healing abutments displayed a higher surface roughness than titanium (S a 0.41 µm vs 0.17 µm), although no differences in surface energy were observed. Despite the higher total volume of the biofilm measured on titanium abutments compared to PEEK (696 µm3 vs 419 µm3), no differences in the live/dead bacterial ratio were observed. Conclusions. Bacterial viability of the biofilm did not show a direct relation to the surface characteristics of PEEK and titanium healing abutments.

One Abutment at One Time Concept for Platform-Switched Morse Implants: Systematic Review and Meta-Analysis

Abstract The aim of this systematic review and meta-analysis was to compare the peri-implant vertical bone loss of immediate loading of implant crowns using the one abutment at one time (AOT) protocol and implants with abutment removal (AR). This systematic review with meta-analysis was reported according to the PRISMA statement, with guidance from the Cochrane Collaboration Handbook. A total of 103 publications were identified in the PubMed database and reference lists of examined articles. After the screening of titles and abstracts, the eligibility of eight full-text articles was assessed. Five studies published between 2010 and 2015 were included in the meta-analysis. There was less peri-implant vertical bone loss at implants using an AOT protocol than at implants using AR protocol (WMD -0.19, 95% CI -0.26 to -0.13; p<0.0001; random-effects model). In conclusion, the use of the AOT protocol with platform-switched Morse implants results in less bone loss than do AR procedures, but this effect may not be clinically relevant. The preservation of marginal bone level achieved with the AOT protocol may not enhance the aesthetics. These results should be interpreted with caution.

Resumo O objetivo desta revisão sistemática e meta-análise foi comparar a perda óssea vertical em implantes de carga imediata usando o protocolo de um pilar em um único momento (AOT) e implantes com remoção de pilar (AR). Esta revisão sistemática com meta-análise foi relatada de acordo com a declaração PRISMA, com orientação do Cochrane Collaboration Handbook. Foram identificadas 103 publicações na base de dados PubMed e nas listas de referência dos artigos examinados. Após a triagem de títulos e resumos, avaliou-se a elegibilidade de oito artigos de texto completo. Cinco estudos publicados entre 2010 e 2015 foram incluídos na meta-análise. Houve menos perda óssea vertical peri-implante em implantes usando o protocolo AOT do que nos implantes usando o protocolo AR (WMD -0,19, 95% IC -0,26 a -0,13; p <0,0001, modelo de efeitos aleatórios). Em conclusão, o uso do protocolo AOT com implantes Cone Morse associados a pilares com plataforma switching resulta em menos perda óssea do que os procedimentos AR, mas esse efeito pode não ser clinicamente relevante. A preservação do nível ósseo marginal alcançado com o protocolo AOT pode não melhorar a estética. Estes resultados devem ser interpretados com cautela.

Fracture resistance of zirconia and resin nano ceramic implant abutments according to thickness after thermocycling / 대한치과보철학회지

PURPOSE: The aim of this in vitro study is to investigate load bearing capacity of esthetic abutments according to the type of material and wall thickness. MATERIALS AND METHODS: 70 specimens equally divided into seven groups according to their abutment wall thicknesses. The abutments prepared with titanium 0.5 mm wall thickness were used as a control group (Ti-0.5), whereas zirconia abutments and resin nano ceramic abutments with wall thickness 0.5 mm, 0.8 mm and 1.0 mm were prepared as test groups (Zir-0.5, Zir-0.8, Zir-1.0 and RNC-0.5, RNC-0.8, RNC-1.0). All specimens were tested in a universal testing machine to evaluate their resistance to fracture and all of them underwent thermo-cycling before loading test. Mean fracture values of the groups were measured and statistical analyses were made using two-way ANOVA. RESULTS: Zir-1.0 showed the highest mean strength (2,476.3 ± 342.0 N) and Zir-0.8 (1,518 ± 347.9 N), Ti-0.5 (1,041.8 ± 237.2 N), Zir-0.5 (631.4 ± 149.0 N) were followed. The strengths of RNC groups were significantly lower compared to other two materials (RNC-1.0 427.5 ± 72.1, RNC-0.8 297.9 ± 41.2) and the strengths of all the test groups decreased as the thickness decreases (P < .01). RNC-0.5 (127.4 ± 35.3 N) abutments were weaker than all other groups (P < .05). CONCLUSION: All tested zirconia abutments have the potential to withstand the physiologic occlusal forces in anterior and posterior regions. In resin nano ceramic abutments, wall thickness more than 0.8 mm showed the possibility of withstanding the occlusal forces in anterior region.

Effects of different torque levels on the implant-abutment interface in a conical internal connection

Abstract The fit of the implant-abutment interface was assessed by the metallographic technique and by scanning electron microscopy (SEM), using solid abutment types at different torque levels. Forty Morse taper connections and forty solid abutments were used at different torque levels (repeated after 10 minutes) in the following groups (n = 10): 25 Ncm (group g1), 30 Ncm (group g2), 35 Ncm (group g3), and 40 Ncm (group g4). The samples were embedded in a metallographic resin, sectioned lengthwise, and polished. SEM images were used to measure the linear contacts and the fits between abutments and the internal walls of the implant. The overall mean gap and standard deviation were as follows: 9.0 ± 1.36 µm for group g1, 7.9 ± 2.81 µm for group g2, 2.0 ± 0.76 µm for group g3, and 0.3 ± 0.40 µm for group g4. A significant difference was observed in the average fit values between the groups (p < 0.05). The linear area of contact between the abutment and the implant increased as torque augmented. This study demonstrated that higher insertion torque values in a conical internal connection increase the fit (contact) of the implant-abutment interface.

Avaliação da qualidade da superfície protética em diferentes sistemas: estudo comparativo / Evaluation of the quality of the surface prosthetic in different systems: a comparative study

Introdução: A adaptação e a rugosidade superficial dos componentes protéticos podem determinar a longevidade de uma reabilitação e a qualidade dos tecidos periimplantares. Objetivo: Comparar a topografia superficial de intermediários de implantes de quatro diferentes marcas comerciais disponíveis no mercado brasileiro, bem como analisar a adaptação vertical quantitativamente (µm) da interface pilar implante. Materiais e Métodos: Foramutilizados intermediários mini-cônicos pré-fabricados das marcas SIN (GMcS), Neodent (GMcN), Conexão (GMcC) e Bionnovation (GMcB), pilares calcináveis com cinta de cromo cobalto ou titânio SIN (GCS), Neodent (GCN), Conexão (GCC) e Bionnovation (GCB) e implantes do tipo hexágono externo (HE), 3,75mm de diâmetroe plataforma regular de 4,1mm SIN (GIS), Neodent (GIN), Conexão (GIC) e Bionnovation (GIB). Para avaliar a superfície dos intermediários foi utilizada a técnica de interferometria a laser "sem contato". Os dados coletados foram processados pelo Software Mountains Map Universal, Digital Surf, o qual gerou imagens tridimensionais sendo considerados três parâmetros (Sa, Ssk, Sku). A desadaptação vertical na interface intermediário ­ implante foi analisada por meio da utilização do Microscópio Eletrônico de Varredura (MEV). Resultados: Tanto para intermediário cônico quanto o pilar calcinável da empresa SIN® demonstraram menor desajuste entre os componentes protéticos e o implante. O grupo intermediário cônico e pilar calcinável da empresa Bionnovation® foram os que apresentam maior linearidade superficial quando comparados aos demais grupos. Conclusão: Não foi observado padronização da rugosidade superficial nem da adaptação dos pilares protéticos entre as marcas comerciais estudadas, sendo que estas variações podem ocasionar variações na longevidade da reabilitação.

Introduction: The adaptation and the roughness surfasse of the prosthetic componentes can determine the longevity of a rehabilitation as well as quality of peri-implant tissues Objective: compare four different brands which are available in the Brazilian market, and make a comparison of the topography surface of implants intermediates between them. Also, analyze the vertical adjustment (mM) of the implant abutment interface. Materials and Methods: In this project was used pre-manufactured intermediate mini-tapered of those following brands: SIN (GMC), Neodent (GMCN), Connection (GMCC) and Bionnovation (GMcB). Calcinable pillars strap with cobalt chrome or titanium SIN (GCS), Neodent (GCN) , Connection (GCC) and Bionnovation (GCB) and the hexagonal (HE), 3.75 mm in diameter and 4.1 mm SIN (GIS), Neodent (GIN), Connection (GIC) and Bionnovation regular platform implants (GIB). It was used the contactless interferometry laser technique to evaluate the intermediates surface. It was considered three parameters (Sa, Ssk,Sku) to process the data collected, which was done by the Universal Software Mountains Map, Digital Surf software, and has gotten three dimensional images. The vertical misfit on intermediate-implant interface was analyzed by a scanning electron microscope (SEM).Results: The intermediate tapered, also the SIN® burnout pillar have showed up the lower misfit between the prosthetic components and the implant. On the other hand, The Bionnovation® pillar and the intermediate group, in comparison to the other groups, were those with higher surface linearity. It was not found the standardization of the roughness surfaces as well as of the abutments adaptation between trademarks studied. However, we observed that those variations can change the longevity of the rehabilitation.

Influence of the accuracy of abutment tooth preparation on the marginal adaptation of Co-Cr alloy copings fabricated with a selective laser sintering technology / 대한치과보철학회지

PURPOSE: The purpose of present study is to examine the correlation between the accuracy of abutment preparation and the marginal adaptation of metal coping. With this view, this study compared the correlations regard to the three different manufacturing methods of selective laser sintering technique, milling and casting. MATERIALS AND METHODS: Two master models were made in a different way. First model with deep chamfer margin was prepared directly by a general clinician and the second model was designed by 3-D designing software program with the same abutment preparation principle and produced by computer aided manufacturing. 12 Co-Cr alloy copings were produced respectively with three different method; SLS system, CAD/CAM milling and conventional lost wax technique from each master model. The total 72 copings fully sit on the master model were stereoscopically evaluated at 40 points along the entire circumferential margin. RESULTS: Significant differences in the absolute marginal discrepancies of Co-Cr copings from SLS system (P=.0231) and casting method (P<.0001) were shown between hand preparation model and computer designed model. However, no significant difference was found between the two model groups from milling method (P=.9962). CONCLUSION: Within the limitation of this study, the effect of the accuracy of abutment preparation on the marginal adaptation of Co-Cr coping is statistically significant in SLS system and casting group. The copings produced by SLS system exhibited the lowest marginal discrepancies among all groups, and the marginal gap of this method group was influenced by the accuracy of the abutment preparation.

Preparo de dentes pilares para prótese parcial removível / Preparing abutment teeth for removable partial denture

O sucesso de uma prótese parcial removível depende de muitos fatores. O aspecto mais importante desse tratamento é o planejamento cuidadoso, a execução dos preparos de boca e precisão durante o processo de obtenção da estrutura. Durante as fases clínicas do tratamento, o cirurgião-dentista precisa determinar adequados planos guias, recontorno das faces vestibulares e linguais dos dentes pilares e nichos apropriados para os apoios oclusais. As vantagens são a preservação do periodonto e a melhora do suporte vertical, da retenção e da estabilidade. Este artigo é limitado ao preparo de dentes pilares íntegros para confecção de próteses parciais removíveis .

The success of a removable partial denture is dependent on many factors. The most significant aspect of treatment with removable partial denture is the careful planning and execution of mouth preparations and their accurate reproduction through the fabrication process. During the clinical phases of treatment, the practitioner must establish correct guiding planes, recontouring facial and lingual surfaces and properly contoured rest seats. The advantages are conservation of alveolar support, improved vertical support and retention and improved horizontal stability. This article is limited to the preparation of the patient's intact teeth when the decision has been made to fabricate a removable partial denture .