JOÃO PAULO DA SILVA NETO!
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AVALIAÇÃO DA MICROINFILTRAÇÃO NA
INTERFACE PILAR-IMPLANTE
PIRACICABA
2012
UNIVERSIDADE ESTADUAL DE CAMPINAS
FACULDADE DE ODONTOLOGIA DE PIRACICABA
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JOÃO PAULO DA SILVA NETO
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AVALIAÇÃO DA MICROINFILTRAÇÃO NA
INTERFACE PILAR-IMPLANTE
Orientador: Mauro Antônio de Arruda Nóbilo Co-orientador: Flávio Domingues das Neves
Tese de Doutorado apresentada a Faculdade de Odontologia de Piracicaba da UNICAMP para obtenção do Título de Doutor em Clínica Odontológica na área de Prótese Dental.
Este exemplar corresponde à versão final da Tese defendida pela aluno, e orientada
pelo Prof. Dr. Mauro Antônio de Arruda Nóbilo _____________________________________
Assinatura do Orientador
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FICHA CATALOGRÁFICA ELABORADA POR MARILENE GIRELLO – CRB8/6159 - BIBLIOTECA DA FACULDADE DE ODONTOLOGIA DE PIRACICABA DA UNICAMP
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Si38a
Silva Neto, João Paulo da, 1985-
Avaliação da microinfiltração na interface pilar-implante / João Paulo da Silva Neto. -- Piracicaba, SP : [s.n.], 2012. Orientador: Mauro Antônio de Arruda Nóbilo.
Coorientador: Flávio Domingues das Neves.
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba.
1. Bactérias. 2. In Vitro. 3. Microbiologia. I. Nóbilo, Mauro Antônio de Arruda, 1965- II. Neves, Flávio Domingues das. III. Universidade Estadual de Campinas. Faculdade de
Odontologia de Piracicaba. IV. Título.
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Informações para a Biblioteca Digital
Título em Inglês: Microleakage at the implant-abutment interface Palavras-chave em Inglês:
Bacteria
In Vitro
Microbiology
Área de concentração: Prótese Dental Titulação: Doutor em Clínica Odontológica Banca examinadora:
Mauro Antônio de Arruda Nóbilo [Orientador] Paulo Cezar Simamoto Júnior
Ricardo Faria Ribeiro
Guilherme Elias Pessanha Henriques Marcelo Ferraz Mesquita
Data da defesa: 24-05-2012
DEDICATÓRIA"
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À!Deus!!
Por"estar"sempre"presente"em"meu"coração,"guiando"os"meus"caminhos"e"sonhos."
Sem"ele"nada"disso"seria"possível.""
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Aos!meus!pais!!
Júlio!José!França!de!Araújo!e!Ana!Glória!de!Melo!e!Silva!
Pelo"amor"e"apoio"incondicional"durante"toda"essa"trajetória."Por"fazerem"dos"
meus"sonhos"os"seus,"não"medindo"esforços"para"a"sua"realização,"mesmo"que"muitas"
vezes"tivessem"que"abrir"mão"dos"seus.!
!
Aos!meus!irmãos!
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Tiago!de!Melo!França!e!Rodrigo!de!Melo!França,!pelo"amor,"amizade,"apoio"e"
privações"durante"esses"anos."!
!
À!família!
!
A"todos"os"meus"familiares"e"aqueles"que"me"apoiaram"durante"a"vida"e"a"pósB
graduação,"meu"muito"obrigado,"sem"vocês"esse"sonho"não"seria"possível.!
!
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AGRADECIMENTOS!ESPECIAIS!!
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Ao" Prof.! Dr.
!Mauro! Antônio! de! Arruda! Nóbilo," meu" orientador," pela" confiança"
depositada" e" pelos" ensinamentos" transmitidos," que" contribuíram" para" minha" formação"
profissional"e"pessoal."Agradeço"pela"oportunidade"de"trabalharmos"juntos"e"a"liberdade"
na"busca"pelo"conhecimento."
"
Ao" Prof.! Dr.! Flávio! Domingues! das! Neves," meu" coBorientador," pela" confiança,"
desafios," ensinamentos," oportunidades" e" amizade" que" foram" fundamentais" na" minha"
formação"e"realização"deste"trabalho."Agradeço"a"oportunidade"de"trabalharmos"juntos"e"
de"desfrutar"dos"seus"conhecimentos."
A" Marcel! Prudente," Thiago! Carneiro" e" Marina! Majadas," pela" amizade" e"
companheirismo"durante"a"realização"deste"trabalho."
AGRADECIMENTOS!!
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À" Universidade" Estadual" de" Campinas" (UNICAMP)," na" pessoa" do" Magnífico" Reitor," Prof." Dr.!
Fernando!Ferreira!Costa."" "" À"Faculdade"de"Odontologia"de"Piracicaba"da"Universidade"Estadual"de"Campinas,"na"pessoa" de"seu"Diretor,"Prof.!Dr.!Jacks!Jorge!Júnior"e"Diretor"Associado,!Prof.!Dr.!Alexandre!Augusto! Zaia."" " À"Coordenadora"dos"Cursos"de"PósBGraduação"da"Faculdade"de"Odontologia"de"Piracicaba"da" Universidade"Estadual"de"Campinas"Profa.!Dra.!Renata!Cunha!Matheus!Rodrigues!Garcia.!! "
Ao" Coordenador" do" Programa" de" PósBGraduação" em" Clínica" Odontológica" da" Faculdade" de" Odontologia"de"Piracicaba"–"UNICAMP,"Prof.!Dr."Márcio!de!Moraes.""
"
Aos" Profs.! Drs." Marcelo! Ferraz! Mesquita;! Guilherme! Elias! Pessanha! Henriques;" e" Rafael! Leonardo!Xediek!Consani"por"compartilharem"suas"experiências"e"conhecimentos"de"prótese"
dental," e" principalmente" pela" atenção" dispensada" a" mim" no" laboratório" de" Prótese" Total" da" Faculdade"de"Odontologia"de"Piracicaba"B"UNICAMP.""
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Aos"docentes"do"Departamento"de"Prótese"e"Periodontia,"da"área"de"concentração"de"Prótese" Dentária"da"Faculdade"de"Odontologia"de"Piracicaba"–"UNICAMP,"Profa.!Dra.!Altair!Antoninha! Del! Bel! Cury,! Profa.! Dra.! Célia! Marisa! Rizzatti! Barbosa,! Prof.! Dr.! Guilherme! Elias! Pessanha! Henriques,! Prof.! Dr.! Marcelo! Ferraz! Mesquita,! Prof.! Dr.! Mauro! Antônio! de! Arruda! Nóbilo,! Prof.! Dr.! Rafael! Leonardo! Xediek! Consani,! Profa.! Dra.! Renata! da! Cunha! Matheus! Rodrigues! Garcia,!Prof.!Dr.!Wander!José!da!Silva,!pelos"ensinamentos"transmitidos.""
À" minha" namorada! Marcele! Jardim! Pimentel! pela" sua" alegria," carinho," amor" e" companheirismo,"sendo"presença"essencial"durante"este"período."Estendo"o"agradecimento"a!
sua!família,!pelo"carinho"transmitido.!!! !
Aos" grandes" amigos" de" pósBgraduação,! Ataís! Bacchi,! Alfonso! Sánchez! Ayala," Bruno! Sotto]
Maior,! Eduardo! Souza,! Emmanuel! Nogueira,! João! Lyra,! Lucas! Dantas,! Luís! Raposo,! Mateus! Bertolini! e! Plínio! Senna,! obrigado" por" compartilharem" seus" conhecimentos," tristezas" e"
alegrias" durante" esse" período," espero" que" a" amizade" siga" pela" vida" apesar" da" distância" que" nos"separa.""
"
Às" amigas" de" pósBgraduação," Camila! Heitor! Campos,! Cindy! Goes,! Caroline! Odo,! Gabriela!
Cassaro! de! Castro,! Giselle! Rodrigues! Ribeiro! e! Izabella! Pereira,! pelo" carinho" e" amizade"
construída.!" "
Aos" colegas" do" laboratório" de" Prótese" Total:" Ana! Patrícia! de! Macêdo,! Antônio! Montagner,!
Brunna! Moreira,! Cláudia! Brilhante,! Isabela! Marques,! Jessica! Takahashi,! Juliana! Nunez,! Leonardo! Luthi,! Maíra! Silva,! Manoela! Capla,! Marco! Carvalho,! Mariana! Agustinho,! Sabrina! Rodrigues,! Vanessa! Tramontino! pelo" convívio" no" diaBaBdia" do" laboratório." À" Eduardo,"
responsável"técnico"pelo"Laboratório"de"Prótese"Total"pela"convivência." "
Aos"colegas"de"pósBgraduação"Ana!Lígia!Micelli,!Ana!Paula!Martins,!Antônio!Pedro!Ricomini!
Filho,! Andréia! Araújo,! Arcelino! Farias,! Camila! Lima,! Daniel! Herrera,! Evandro! Figueirêdo,! Frederico! Fernandes,! Germana! Camargos,! Gojko! Civic,! Hugo! Vale,! Indira! Cavalcante,! José! Sabino,! Larissa! Vilanova,! Letícia! Gonçalves,! Lívia! Forster! Ribeiro,! Luana! de! Aquino,! Lucas! Zago,! Naiara! de! Paula,! Marcelo! Mendes,! Sílvia! de! Lucena,! ,! Sheila! Porta,! Tarcísio! Oliveira,! Thaís!Gonçalves,!Valdir!Andrade,!William!Custódio"pelo"convívio"e"troca"de"conhecimentos." !
À" Faculdade" de" Odontologia" da" Universidade" do" Federal" de" Uberlândia" em" nome" do" Reitor"
pessoal,"e"aos"Professores"Drs."Carlos!José!Soares,!Paulo!Simamoto,!Adérito!da!Mota,!Ricardo! Prado,! Paulo! Vinicius! Soares," pelo" apoio" incondicional" em" todos" os" momentos" e"
principalmente"na"minha"vinda"para"Piracicaba.! "
À" NEODENT! implante! osseointegrável" em" nome" da" Profa.! Ivete! Sartori" pela" doação" do"
material"utilizado"nesta"pesquisa"e"em"toda"a"minha"pósBgraduação." "
À" Coordenação" de" aperfeiçoamento" pessoal" de" nível" superior" (Capes)," pela" bolsa" de" Doutorado"concedida"durante"parte"do"doutorado. ""
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A"todos"aqueles"que"de"uma"forma"ou"de"outra"colaboraram"para"a"realização"deste"trabalho," que"participaram"junto"comigo"e"estiveram"presentes"em"minha"vida."
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“Educação!não!transforma!o!mundo,!
educação!transforma!pessoas,!
pessoas!transformam!o!mundo...”.!
Paulo!Freire!
RESUMO
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A conexão entre implante e pilar está diretamente relacionada com o infiltrado bacteriano e a presença de células inflamatórias que levam à perda óssea ao redor da microfenda formada por esta interface. Entretanto, ainda não há consenso quanto aos resultados dos testes in vitro e as metodologias aplicadas para a avaliação da microinfiltração nesta interface. O objetivo neste estudo foi: 1) avaliar, por meio de uma revisão sistemática, a influência das metodologias nos resultados dos estudos in vitro de microinfiltração na interface implante-pilar (I-P); 2) Avaliar, experimentalmente a microinfiltração bacteriana na interface I-P em implantes cone Morse inoculados com diferentes volumes de suspensão bacteriana. Para a revisão sistemática, foi realizada uma procura nas bases de dados MEDLINE, EMBASE e Cochrane, por estudos in vitro avaliando a microinfiltração na interface I-P publicados no período entre 1990 e agosto de 2011. Após a aplicação dos critérios de inclusão e exclusão, os artigos selecionados foram arranjados em tabelas e submetidos a análise descritiva. Para o ensaio de microinfiltração bacteriana foram selecionados implantes e pilares cone Morse, que por sua vez foram divididos em 2 grupos em função do tipo de pilar: parafuso passante (PP) e corpo sólido (CS). Posteriormente, os grupos foram subdivididos em 4 subgrupos, em função do volume de suspensão bacteriana inoculado nos implante (n=6): PP1: 0,1µL; PP3: 0,3µL; PP5: 0,5µL; PP7: 0,7µL; CS1: 0,1µL; CS3: 0,3µL; CS5: 0,5µL e CS7: 0,7µL. Uma suspensão bacteriana de Escherichia coli ATCC 35218 foi inoculada no interior dos implantes com volume de acordo com o respectivo grupo, sendo os componentes apertados segundo recomendações do fabricante. Após a inoculação os espécimes foram imersos em solução nutritiva bacteriana estéril para avaliação de um possível extravasamento do inoculo (grupo controle). Posteriormente, os conjuntos foram incubados em uma nova solução até o recobrimento da junção para avaliação microbiológica. A microinfiltração foi avaliada pela alteração na claridade da solução a cada 24 horas durante 7 dias. Ao final deste período os conjuntos foram reabertos para avaliação da viabilidade bacteriana. A revisão mostrou alta variabilidade de resultados e de tipos de ensaio de microinfiltração entre os estudos, apresentando alguns pontos críticos como volume bacteriano inoculado; concentração bacteriana; método de inoculação; períodos de acompanhamento e verificação de viabilidade bacteriana. No ensaio todos os espécimes inoculados com 0,7µL e uma amostra de CS5 apresentaram
turbidez no grupo controle após as primeiras 24 horas sendo excluídas do estudo. Durante os sete dias de acompanhamento nenhum espécime apresentou indicativo de microinfiltração bacteriana. E após este período, a viabilidade bacteriana foi confirmada em todos os espécimes avaliados. Dentro das limitações deste estudo pode se concluir que a falta de padronização entre os estudos in vitro dificulta comparações e pode explicar algumas divergências entre seus resultados. Não foi observada microinfiltração na interface I-P em implantes com conexão do tipo Morse e o volume de 0,7µL excedeu a capacidade máxima do sistema avaliado.
ABSTRACT
The connection between implant and abutment is directly related to bacterial infiltration and it has been correlated with the presence of bacterial infiltration and inflammatory cells that can lead to bone loss around the marginal bone crest. However, there is no consensus to the in vitro tests results and methodologies for the assessment of microleakage at this interface. The aims of this study were to evaluate: 1) the influence of methodological aspects in variations on the results of in vitro microleakage studies of the implant-abutment (I-A) interface; 2) the bacterial microleakage in the I-A interface of Morse tapered implants inoculated with different volumes. For the review, MEDLINE, EMBASE and Cochrane Library database were consulted for in vitro studies published between 1990 and August 2011. For those studies that met the inclusion and exclusion criteria, data were arranged in tables and subjected to descriptive analysis. In the bacterial microleakage test, Morse tapered implants and abutments were selected and assigned into two groups depending on the abutment type: passing screw abutment (PS) and solid abutment (S), and then further subdivided into four subgroups depending on the volume of inoculation in the inner part of the implant (n=6): PS1: 0.1µL; PS3: 0.3µL; PS5:0.5µL; PS7: 0.7µL; S1: 0.1µL; S3: 0.3µL; S5: 0.5µL e S7: 0.7µL. For the control group, the presence of external contamination was assessed. A bacterial suspension was inoculated in the implants and incubated for microbiological analysis. The microleakage was evaluated every 24 hours during 7 days. After this period, the implants were disassembled for confirmation of the bacterial viability. All the specimens inoculated with 0.7 µL and one sample of S5 presented turbidity in the control group after the first 24 hours and were excluded of the study. During the seven days, none of the specimens presented positive results for microleakage and the bacterial viability was confirmed in all evaluated specimens. Within the limitations of this study, it can be concluded that a lack of standardization hinders comparisons among studies and can give an explanation of some divergences among them; during the seven days, none of the specimens presented positive results for microleakage and the bacterial viability was confirmed in all evaluated specimens; the volumes 0.1, 0.3, and 0.5µL did not present bacterial microleakage in the I-A interface. The volume of 0.7µL is excessive and lead to false results of microleakage.
SUMÁRIO
INTRODUÇÃO... 1
CAPÍTULO 1: influence of methodological aspects in microleakage ……… 4
implant-abutment interface tests: a critical review of in vitro studies
CAPÍTULO 2: Bacterial microleakage at the implant-abutment interface ……… ... ... ... 26
in Morse taper implants inoculated with different volumes
CONSIDERAÇÕES GERAIS ... 40
CONCLUSÕES GERAIS... 42
REFERÊNCIAS ... 43
ANEXOS
1 - Comprovantes de Submissão……….. 46
2 – Ensaio de microinfiltração in vitro ……… 48
INTRODUÇÃO
Os implantes originalmente desenvolvidos por Brånemark possuíam o desenho hexagonal externo na plataforma, utilizado para instalação dos implantes e conexão do intermediário protético. Este tipo de conexão apresentava perda óssea ao seu redor considerada normal, de aproximadamente 1,0 mm no primeiro ano em função e menos de 0,2 mm após o primeiro ano (Albrektsson et al.,1986). Contudo o que anteriormente foi considerado sucesso, para os padrões estéticos atuais, passou a ser considerado uma limitação devido a recessão tecidual comumente apresentada por essas áreas, principalmente na reabilitação de dentes anteriores (Donovan et al., 2010).
A manutenção da altura do osso peri-implantar é pouco previsível (Lazzara e Porter, 2006), sua manutenção é subjetiva e está relacionada a aspectos mecânicos (McGlumphy et al., 1998; Khraisat et al., 2002) e microbiológicos da conexão implante-pilar (I-P) (Broggini et al., 2003; Broggini et al., 2006; Bozkaya e Muftu, 2003). É comprovado que o tipo de conexão entre I-P está diretamente relacionado com o infiltrado bacteriano e a presença de células inflamatórias que levam a perda óssea ao redor da microfenda existente na região da conexão (Broggini et al., 2003; Broggini et al., 2006). O desajuste entre I-P tem sido indicado como um dos fatores causais das falhas protéticas (Goodacre et al., 2003) e, possivelmente responsável pela diminuição do osso ao redor da plataforma do implante (Broggini et al., 2003; Broggini et al., 2006).
O grau de infiltração bacteriana entre implante e componentes protéticos depende de fatores variáveis como a precisão de assentamento dos componentes, torque e micromovimentos entre as partes conectadas durante a função (Quirynen et al., 1994; Byrne et al., 1998; Scarano et al., 2005; Steinebrunner et al., 2005; do Nascimento et al., 2008). A prevenção da infiltração bacteriana na interface I-P é um dos maiores desafios
na construção dos sistemas modernos de implantes em duas peças, na tentativa de minimizar as reações inflamatórias e maximizar a estabilidade do osso ao redor da plataforma do implante (Dibart et al., 2005; Harder et al., 2010). Microfendas e pequenos espaços ainda estão presentes nos sistemas atuais. As empresas visam diminuir esta penetração aumentando a estabilidade da junção, reduzindo sua micromovimentação, e construindo imbricação mecânica no processo de apertamento do pilar de alto nível de precisão, fator importante na prevenção de infiltrados (Dibart et al., 2005; Zipprich et al., 2007). Este fato vem ao encontro a necessidade de diminuição de custos, a popularização dos implantes, tal como da técnica de implantação. Os sistemas nacionais têm investido nesse sentido, na tentativa de oferecer um sistema de excelência quando comparados a sistemas importados, porém, mais acessíveis atingindo as expectativas de profissionais e pacientes.
Grande parte dos estudos atribui à reabsorção da crista óssea principalmente a três fatores: a presença de um infiltrado inflamatório crônico na interface I-P (Jansen et
al., 1997), a distribuição de tensões nesta região (Tada et al., 2003) e a presença de micromovimentos entre implante e componentes protéticos (Steinebrunner et al., 2005). Diversas metodologias têm sido aplicadas utilizando bactérias (Quirynen et al., 1994; Jansen et al., 1997; Guindy et al., 1998; Besimo et al., 1999; Piatelli et al., 2001; Steinebrunner et al., 2005; Dibart et al., 2005; Duarte et al., 2006; Pappalardo et al., 2007; do Nascimento et al., 2008; Barbosa et al., 2008; do Nascimento et al., 2009; do Nascimento et al., 2009b; Silva-Neto, 2009; Tesmer et al., 2009; Aloise et al., 2010; Teixeira et al., 2011; Koutouzis et al., 2011), suas toxinas (Harder et al., 2010) e corantes (Gross et al., 1999; Piatelli et al., 2001; Coelho et al., 2008) para avaliar a microinfiltração da interface I-P de diferentes sistemas e tipos de conexões. Entretanto seus resultados
demonstram alta variabilidade. O que sugere, que esta variabilidade pode estar relacionada às metodologias aplicadas.
Silva-Neto 2009, reportou em seu estudo a necessidade de padronização dos ensaios experimentais avaliando a microinfiltração na interface I-P no que se refere ao volume inoculado, tipo de inoculação, apreensão dos implantes e condições do experimento. Ainda relatou a dificuldade que é se trabalhar em um ambiente de proporções milimétricas e a utilização de bactérias. Segundo Coelho et al. 2008, enquanto não houver uma compreensão da magnitude desta microfenda e sua influência na colonização e proliferação de bactérias, não se pode prover nenhuma informação sobre a transferência de fluídos entre as partes internas e externas da conexão I-P.
Diante deste contexto, o presente trabalho teve como objetivo avaliar: 1) A influência das metodologias nos resultados dos estudos in vitro de microinfiltração; 2) Avaliar a microinfiltração bacteriana na interface I-P em implantes cone Morse inoculados com diferentes volumes de suspensão bacteriana.
CAPÍTULO 1
1Influence of methodological aspects in microleakage implant-abutment interface tests: a critical review of in vitro studies
João Paulo da Silva-Neto, DDS, MSc – Department of Prosthodontics and
Periodontology, State University of Campinas, Piracicaba Dental School, Brazil.
Mário Paulo Amante Penatti, BDS, MSc, PhD – Professor, Healthy Technical School,
Federal University of Uberlândia, Uberlândia, Brazil.
Paulo Cézar Simamoto-Júnior, DDS, MSc, PhD - Professor, Healthy Technical School,
Federal University of Uberlândia, Uberlândia, Brazil.
Flávio Domingues das Neves, DDS, MSc, PhD - Associate Professor, Department of
Occlusion, Fixed Prostheses, and Dental Materials, Federal University of Uberlândia, School of Dentistry, Uberlândia, Brazil.
Mauro Antônio de Arruda Nóbilo, DDS, MSc, PhD – Titular Professor, State University
of Campinas, Piracicaba Dental School, Brazil.
Correspondence to: Dr. João Paulo da Silva Neto, Piracicaba Dental School, University
of Campinas – Department of Prosthodontics and Periodontics, Av. Limeira, 901 Piracicaba SP 13414-903, Brazil. Phone: +55 (19) 2106-5350; email: [email protected]
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Este capítulo foi aceito no The international Journal of Oral and Maxillofacial Implants eAbstract
Purpose: This study aimed to evaluate the influence of methodological aspects on the
results of in vitro microleakage studies of the implant-abutment (I-A) interface. Materials
and Methods: The MEDLINE, EMBASE and Cochrane Library database were consulted
for in vitro studies published between 1990 and August 2011. For those studies that met the inclusion and exclusion criteria, data were arranged in tables and subjected to descriptive analysis. Results: Twenty-one were found eligible after application of the inclusion/exclusion criteria. Sixteen studies used bacteria (76.2%); one, bacterial toxin (4.76%); one, saliva (4.76%); two dyes (9.52%); and one, the association of dyes and bacteria (4.76%). Eight studies evaluated the microleakage sense I/E (38.1%) and nine E/I (42.85%), while four investigated their association of them (19.05%). The volume inoculated inside the implants ranged from 0.1 to 5.0 mL. The bacterial concentrations used in the tests ranged from 2.41 x 106 to 8 x 108 CFU/mL. Oral bacterial flora, mixtures of bacteria, toluidine blue and gentian violet, and Lipopolysaccharide of Salmonella enterica bacterial toxins were used. The monitoring period of test results ranged from 24 hours to 11 weeks for bacteria, 5 min to 7 days to dye, and 7 days for bacterial toxins. In four studies, microleakage was correlated with the I-A microgap size. The external hexagon system showed higher results for microleakage, followed by trilobe, internal hexagon, and internal taper. Conclusion: It was concluded that the lack of standardization hinders difficulties comparisons between the studies and could explain divergent results. It is suggested for future studies that special emphasis be placed upon inoculation and analysis for the specific volume for each system, lower concentrations of inoculated bacterial suspensions, and shorter follow-up time when using bacteria.
Introduction
The connection type between implant-abutment (I-A) can be directly related to bacteriological leakage and the presence of inflammatory cells that lead to bone loss around the existing microgap at the region of the connection.1 Originally, osseointegrated
implants had the external hexagonal (EH) design on the platform, used on the installation of the implants and also to connect the intermediate implant.2 This type of connection
presented normal bone losses around the implants, especially in the first year of function.3
Three reasons have been advocated as the main responsible causes of this fact: the chronic inflammation near the I-A interface;4 the stress distribution at the marginal bone
crest region;5 and the micro movement of the I-A interface.6 The leakage degree between
implant and prosthetic components depends on various factors, such as the precise disposal of components, torque and micro movements between the connected walls when in function.6-10
One of the biggest challenges on the assembly of modern implant systems in two stages is to prevent the bacterial infiltration within the I-A interface, in order to minimize inflammatory reactions to maximize bone stability around the implant’s platform.8,10 Implant companies aim to diminish this penetration, augmenting the stability of the I-A junction, providing high-level mechanical retention on the tightening process of the prosthetic components, an important factor to prevent infiltrates.7,8,11 Many in vivo studies have been
carried out in order to find out the influence of the microgap on the marginal leakage, as well as the real advantages provided by the various types of implant systems available in the market. These studies demonstrated favorable clinical results, regarding marginal bone stability, when compared to external junctions.11,12
Bacteriological microleakage studies used several kinds of bacteria, from facultative to obligate anaerobes, varying in size from 1 to 10 µm4,6,8,9,13-25 as well as their
toxins,10 saliva26 and stains,7,16,27 both with extremely small molecules, based on the fact
that some studies state that the microgap between the implant and the prosthetic components generally located subgingivally is about 1 to 49 µm in length.4 These
microgaps represent, consequently, the ideal potential place for plaque retention, allowing the microbial fluid to flow.1
Several methodologies have been used in order to determine both the magnitude4,8,10,22 and the real influence of this microgap on the leakage process.6 Some
studies analyze of this leakage both from the inner parts of the implants to the outside (I/E)4,6,9,10,18,19,21,27 and, on the contrary, from the external portion to the internal parts of an implant (E/I)7,13,16,17,22,23,25,26 or both,8,14,15,24 analyzing by qualitative and quantitative
methods, from the turbidity analysis of nutritional broth to the bacterial DNA analysis.18,21,26 However, there are several critical points in these methodologies, that can actuate as potential factors that lead to false positive/negative results. Amid these factors are: the usage of forceps or pliers to fix the implants; the freehand inoculation of bacterial broth into the implants; the total coating of the implants, owing to the fact that they could induce a potential penetration of fluid within the abutment-screw interface; the usage of the same torquemeter for several samples; the non-determination of the implant’s internal volume; the type of bacterium and its survival in the in vitro conditions of the study; and even the disinfection procedures, carried out in order to evaluate the E/I orientation of the fluid flow. This fact can be proved due to the variability of results observed in these studies. Therefore, the aim of this review was to investigate the influence of methodological aspects on the results of in vitro microleakage I-A interface studies.
Materials and methods
A survey was carried out in the MEDLINE, EMBASE, and Cochrane Library database, searching for available articles in the National Medicine Library that evaluated microleakage in the I-A interface from 1990 to August 2011. The key words were typed in combination with “dental implants” and “leakage”. Fifty-two MEDLINE, forty-four EMBASE, and two Cochrane Library studies were found for a total of 98 articles at the initial period of the survey. The abstracts of the articles were retrieved, reviewed, and sorted based on the following inclusion and exclusion criteria. Excluded were the following: clinical microleakage evaluations, in vitro microleakage tests having used implants are not used in dental rehabilitation and review articles (Table 1). The selected articles dealt with evaluation of microleakage in the I-A interface, both in the internal/external and external/internal orientations, using bacteria, stains and bacterial toxins, or the association of two or more methodologies.
Some articles were not listed in the initial survey, but they were cited by the selected studies, which addressed in vitro tests and satisfied the inclusion criteria were also selected. Data of interest were collected and divided into tables, according to the results and methodological procedures, for the descriptive analysis of all data, respectively (Tables 2 and 3).
Results
After the application of the inclusion and exclusion criteria of the 98 articles initially listed, eighty-one were excluded from selection, leaving seventeen articles. Four additional articles were selected because they were cited in the selected studies and satisfied the inclusion criteria, totalizing 21 articles.
A total of 21 studies evaluated the occurrence of microleakage in the I-A interface. Sixteen used bacteria (76.2%), one used bacterial toxin (4.76%), two used stains (9.52%), one used saliva (4.76%) and one used the association of stains and bacteria (4.76%). From all these studies, eight evaluated microleakage in the I/E orientation (38.1%), nine in the E/I orientation (42.85%), and in four studies, the association of both orientations was evaluated. Several types of systems were evaluated: internal junctions (hexagon, intra-lock, camlog, trilobe, conical) and external hexagonal junctions. In three studies (14.28%), the use of silicon and/or varnish was evaluated in an attempt to hinder the occurrence of microleakage.4,6,17 The number of samples tested varied from 3 to 30 sets of I-A. From the
studies that evaluated microleakage in the I/E orientation, only two had differentiated the bacterial suspension volume, with regard to the system (9.52%).21,24 The volume inoculated within the implants varied from 0.1 to 5.0 µL. Nine studies (42.84%) did not specify the method of fixation of implants in order to inoculate and/or install their components. Seven used pliers (33.32%), three used forceps (14.28%), and two used vises (9.52%).
The bacterial concentrations used in the tests varied from 2.41 x 106 to 8 x 108 CFU/mL. All bacteria originated from the oral flora, with some species mixtures:
Pseudomonas aeruginosa, Actinobacillus actinomycetemcomitans, Escherichia coli,
Staphylococcus aureus, Streptococcus faecalis, mutans, sobrinus, oralis, and
Fusobacterium nucleatum. In the incubation and monitoring processes, the sets were
partially or completely immersed, or both. According to the authors, the solid shape of the abutment justifies its complete immersion,8,10,21 as well as vacuum devices7 and sealing of
the abutment’s screw by cyanoacrylate-based adhesives.9,18-20 The monitoring period of
days for bacterial toxins. Only two studies (9.52%) submitted the specimens under mechanical loading evaluation.6,25
For the bacterial studies, the EH system presented higher results for microleakage, varying from 10% to 100% of the total amount of tested samples, followed by trilobe, internal hexagon, and tapered internal implants. Generally, microleakage occurred on the first three days of experiment. In 4 studies (19.04%), microleakage was correlated with the microgap size, located between the I-A interface. Different torques were applied on the prosthetic components, most of them following the manufacturer’s recommendations and varying from 10 to 45 Ncm. Torque had influenced the results when compared to similar systems.7 The used stains were toluidine blue and gentian violet. In studies in which both
methods were used in combination (stains and bacteria), no differences were found in the results. The lypopolisaccharide from Salmonela enterica was used in tests with bacterial toxins.10
The presence of microleakage in the I-A interface was more evident in studies that carried out this evaluation by means of staining and bacterial toxins. It was present in all studies that used this methodology.
Discussion
Twenty-one studies evaluated microleakage in vitro: 76.2% using bacteria, 4.76% using bacterial toxins, 9.52% using stains, 4.76 using saliva, and 4.76% using bacteria and stain association, in order to evaluate microleakage in the I-A interface of different systems and connection types. Nevertheless, the results demonstrated high variability when compared to similar methodologies (Table 2). This fact suggests that there were methodological divergences that derailed the reproduction and comparison.
When observing Table 3, with the methodological aspects of studies that evaluated marginal infiltration in implants, it is possible to observe a variation of inoculated volumes, used in those studies that evaluated the bacterial outflow in the I/E orientation, varying from 0.1 to 5.0 µL.4,6,8,9,14,15,18-21,24,27 This is a natural fact due to the diversity of the
systems. However, the inoculum level inside the internal parts of the implant can influence on the outflow, being a biasing factor when the same volume is used for different systems that are from different commercial brands. Only two studies verified the ideal inoculum volume for different systems.21,24
Microbiological studies are generally very sensible, due to the handling of biological agents, which are susceptible to alterations of the environment in which they are stored and used. This fact becomes even more critical when this method of evaluation has millimetric proportions and limited conditions of nutrition and oxygenation of the microorganisms, as similarly observed in microbiological tests in vitro using implants. In 9 studies, the fixation method of the implants for inoculation and adaptation of components was not specified. Pliers were used in 7 studies and forceps were used in 3 studies to fix the implants. In most cases, the use of pliers and/or forceps to inoculate and to adapt the intermediates is still aggravated by free-hand inoculation.4,6,8-10,14,15,18,20,21,25,27 The implant’s orifice is, in most cases, approximately 2 to 3 mm in diameter. This reduced space requires high precision from the operator because a possible touch on the borders of the implant could generate false positive results, facilitating the bacterium’s passage to the external environment. Moreover, when exacerbated force is used to fix the implant in areas close to the platform, it could generate deformation on the titanium implant body, as it is a ductile material.28 Based on this reason, it would be more prudent to use devices that
provide a more accurate method of inoculation, as well as fixation by means of apically positioned devices, in relation to the implants, as used in two studies.21,27
Different types of bacteria were used in the in vitro tests, from facultative to obligate anaerobes. Their use can be justified by their reduced size, the ability of permeability through the microgap of the I-A interface and because they are common microorganisms in the periimplant area. The used concentration in the inoculated bacterial suspensions varied from 2.41 x 10⁶ to 8 x 10⁸ CFU/mL. Nevertheless, limited volumes of inoculum, elevated bacterial concentrations (higher than 1.5 x 10⁸ CFU/mL), and environments with limited conditions of oxygenation and nutrition, such as the interior of implants, represent extremely adverse environments for bacterial reproduction and survival. These environments could lead to false negative results due to the death of these microorganisms within the implants. Hence, longer monitoring periods (over 7 days) must be avoided. Furthermore, it is important to notice that, at the end of the monitoring periods, the implants must be reopened in order to verify bacterial viability; this method was performed in only one of the test in this study.24 The analysis of the bacterial microleakage
results in all in vitro tests occurred within the first 3 days of evaluation. This fact may happen due to a probable reduction of the liquid and nutrients that are necessary to the bacteria’s survival. Thus, there is a significant reduction in the number of bacteria, reinforcing the theory that after long monitoring periods, a considerable loss in motility and reproduction can occur. With compromised ability of locomotion, bacteria are much more susceptible to death, when attempting to reach the external environment.
Evaluations of the microleakage in the I-A interface, from E/I orientation, were found in 9 studies (42.85%).7,13,16,17,22,23,25,26 The results varied from absence of microleakage to contamination in 100% of the samples. A variation from 10 to 100% of the
evaluated specimens could be observed in the EH system. There are some drawbacks to this methodology because of the lack of confidence during the decontamination of the samples and the possibility of false positive results. These disinfections are sometimes performed by air blasts,18,22 and sometimes by disinfectant substances.8,14-17,22,24,26
Moreover, the evaluation of results is performed, in most cases, only one time, hindering the correct analysis of growth and mobility of a bacterium as a long period of time passes. Furthermore, the collection method of the material with microbrushes and absorbent paper cones in the internal portions of the specimens is questionable. Four studies (19.04%) report that the analysis of the E/I orientation opens a new possibility of quantitative evaluation of the microleakage degree, by means of bacterial DNA analysis.18-20,26
However, this analysis has some limitations; the method is more difficult to perform and can only identify bacteria from a certain number of colonies. It is important that a methodology be defined as capable of being executed, thus generating reproducibility in order to facilitate reliable comparisons among studies.
In 4 studies (19.04%), there were no differences among the results when using both I/E and I/E orientation methods.8,14,15 In one study (4.76%), the methodology using bacteria and stains was performed, comparing both agents.16 Nevertheless, no significant differences were found among these studies. This result goes against other tests that used stains. When compared to those studies that used bacteria, the latter presented higher levels of microleakage that became higher over time. According to the authors, the advantages of the use of stains are the following: the approximated size between particles and bacterial toxins, ease of use, and ability to quantify the results. One study used bacterial toxins to evaluate bacterial microleakage, and its results were positive for more than 90% of the evaluated internal conical implants. These implants also presented better
retention and smaller I-A interface.10 Regarding the use of bacterial toxins, the advantages
of this method are the smaller size of the molecules and the fact that these are the primary causes of marginal bone loss.
The number of evaluated samples for each group varies from 3 to 12 sets. However, tests that evaluated microleakage, mainly those using bacteria to simulate similar conditions to the periimplantar environment, have a qualitative character, and a reduced number of specimens can lead to tests with no statistical significance. It is difficult to carry out studies with implants due to the high cost of samples and to the onerous character of their execution. Despite that, it is important to have enough samples in order to obtain reliable results. According to the tests evaluated in this study, the minimal number of samples per group should be from 8 to 10 sets.
Five studies performed partial immersion (23.8%) of the I-A sets.4,6,22,23,27 Ten performed total immersion (47.6%)8,18-20,24-26 and both types of immersion were performed
in 4 studies (19.04%),13-16 with one of them in two different groups.16 Total immersion is justified, according to the authors, by the abutment’s solid body,8,10,21 confection of vacuum
devices,7 and sealing of abutment’s screw by cyanoacrilate-based adhesives.9,18-20 However, in abutments that do not have a solid body, the abutment-screw interface can denote a potential area for fluid flow, resulting in data that did not represent the ability of permeability of the I-A interface.13,24
In most tests, the torques applied during the installation of abutments followed the manufacturer’s recommendations and varied from 10 to 45Ncm. Sets that received higher torques presented lower leakage levels.7 The hexagonal external junction presented
differences between internal and external connections.6 Studies that have correlated the
systems’ microgap did not find statistically significant differences in static conditions among the interfaces, whereas all of them presented sizes smaller than 10 µm, and the material used in the microleakage tests always presented smaller proportions than this interface.4,8,10,16 The measurement of the microgap formed by the I-A connection is
currently a very questionable aspect, including its influence on the mechanic and biological aspects.4,10 Even so, some studies argued that this gap is about 1 to 49 µm, depending on
the system.4 Hence, it can be augmented when submitted to a mechanical loading,6 a
factor that could favor a higher influx of bacteria into the interface.
The most recent in vitro studies that evaluate bacteriological microleakage demonstrated that in static conditions,8,9,18-20 this microleakage is not very relevant, mainly when using corpuscular bacteria in these tests, dropping the anterior and contrary hypotheses of earlier studies,4,14-16 mostly when external hexagons were evaluated, this is in spite existing evidences that support an augmentation of the microgap when submitted to cyclic loading, promoting greater infiltration of fluids, mainly on the external junction, due to its reduced stability.6,8 One study reported that even stable internal conical junctions having a microgap of approximately 1 to 4 µm allowed the infiltration of toxins of molecular size, present on the bacteria’s cell wall the main causers of bone crest destruction.10 This
statement suggests that the marginal bone loss process is more directly linked to the distance from the junction to the bone crest12,29 than to the flux of bacteria in this area.1,4
One study reported the behavior of various systems under cyclic loading, exhibiting that all those systems presented microleakage after 1,200,000 cycles.6 This fact
demonstrates that, under mechanical loading, the connections suffer micro-movements that can influence interface leakage.
However, more studies must be conducted that compare the infiltration of corpuscular bacteria, as well as their toxins in different systems and under loading, in order to evaluate the real relevance of this microgap on the bacterial flux more accurately. Therefore, it is necessary that the methodology be well executed, minimizing operator’s influences.
In regard of the clinical implications, although it has been known for more than fifteen years that bone loss occurs in the first year and stabilizes thereafter one should consider that the majority of the cases were complete rehabilitations and presented significant bone loss. In these situations, it was totally uninteresting to discuss the marginal bone loss when the ad modum Branemark systems could rehabilitate with competence the absence of teeth. However, with the evolution of the implantology, the search for highly aesthetic solutions in situations of partial teeth loss became expected by patients. Thus, in aesthetic regions, mainly when the lip line is high, a future decrease in the papillae between the implants or between tooth and implant may compromise a long-term rehabilitation, which raises the subject of marginal bone loss.
Nowadays, one should consider the abovementioned hypotheses for marginal bone loss within the historical context. However, studies have shown that ad modum Branemark implants, exposed and without load, also presented marginal bone loss, putting into question the role of the load.30 It is reasonable to suppose that when excessively
loaded, the marginal bone loss may be related to the load; this is observed in clinics when the torque loss or fracture of the screw causes overloading in other implants, and those lose bone in the fulcrum area (bone crest). If this loading is not stopped or minimized, it will lead to progressive bone loss until the loss or fracture of the implant.31
Thus, there are presently reasons to believe that the presence of bacteria in the implant-abutment interface and mainly toxins produced by them with the micro-motion, which enhances the flow in the interface, are the great villains of marginal bone loss. Studies and catalogs of companies promise more stable and hermetically sealed joints, with switch configuration, that promise to minimize or even to avoid marginal bone loss.32
However, this contention is questioned by some authors.10,24,27 Therefore, it is necessary to
standardize the in vitro tests in order to obtain the correct knowledge about the microleakage of the different systems, and to correlate them to the biomechanical aspects of the joints, simulating masticatory function to plan the system configuration as a whole (joint, microgap, abutments size and implant platform) in order to improve predictability regarding soft and hard tissues.
In the future, in vitro microleakage tests will pay special attention to the internal volume difference for different systems, as well as the methodology for fixation and inoculation of the implants, the leakage control, the external decontamination methods, and bacterial viability after the trial period. The advantages of using stains could be questioned, whereas its molecules present closer sizes to the toxins, which are responsible for bone loss. The cyclic loading could generate micromovements that favor microleakage. Therefore, further studies should be carried out to answer such questionings.
Conclusion
Within the limitations of this study, it can be concluded that a lack of standardization hinders comparisons among studies and can give an explanation of some divergences among them. It is suggested, for further studies, that researchers focus on the
inoculation method and specific volume analysis for the systems to be studied, as well as lower concentrations of the inoculated bacterial suspensions and critical monitoring when using bacteria.
Acknowledgements
The authors would like to thank to the undergraduate students Marcel Prudente and Thiago de Almeida Prado Naves Carneiro for their assistance during the discussion of the articles involved in this study.
References
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2. Brånemark PI, Hansson BO, Adell R, Breine U, Lindström J, Hallén O, Ohman A. Osseointegrated implants in the treatment of the edentulous jaw. Experience from a 10-year period. Scand J Plast Reconstr Surg 1977;16:1-132.
3. Albrektsson T, Zarb G., Worthington P, Eriksson AR. The long-term efficacy of currently used dental implants: a review and proposed criteria of success. Int J Oral Maxillofac Implants 1986;1(1):11-25.
4. Jansen VK, Conrads G, Richter EJ. Microbial leakage and marginal fit of the implant-abutment interface. Int J Oral Maxillofac Implants 1997;12(4):527-540. 5. Tada S, Stegaroiu R, Kitapura E, Mikayawa O, Kusakari H. Influence of implant
design and bone quality on stress/strain distribution in bone around implants: a 3-dimensional finite element analysis. Int J Oral Maxillofac Implants 2003;18(3):357-68.
6. Steinebrunner L, Wolfart S, Bössmann K, Kern M. In vitro evaluation of bacterial leakage along the implant-abutment interface of different implant systems. Int J Oral Maxillofac Implants 2005;20(6):875-881.
7. Gross M, Abramovich I, Weiss EI. Microleakage at the abutment-implant interface of osseointegrated implants: a comparative study. Int J Oral Maxillofac Implants 1999;14(1):94-100.
8. Dibart S, Warbington M, Su MF, Skobe Z. In vitro evaluation of the implant-abutment bacterial seal: the locking taper system. Int J Oral Maxillofac Implants 2005;20(5):732-737.
9. do Nascimento C, Barbosa RE, Issa JP, Watanabe E, Ito IY, Albuquerque RF Jr. Bacterial leakage along the implant-abutment interface of premachined or cast components. Int J Oral Maxillofac Surg 2008;37(2):177-180.
10. Harder S, Dimaczek B, Açil Y, Terheyden H, Freitag-Wolf S, Kern M. Molecular leakage at implant-abutment connection--in vitro investigation of tightness of internal conical implant-abutment connections against endotoxin penetration. Clin Oral Investig. 2010;14(4):427-432.
11. Donovan R, Fetner A, Koutouzis T, Lundgren T. Crestal bone changes around implants with reduced abutment diameter placed non-submerged and at subcrestal positions: a 1-year radiographic evaluation. J Periodontol. 2010;81(3):428-434. 12. Canullo L, Fedele GR, Iannello G, Jepsen S. Platform switching and marginal
bone-level alterations: the results of a randomized-controlled trial. Clin Oral Implants Res 2010;21(1):115-121.
13. Quirynen M, Bollen CM, Eyssen H, van Steenberghe D. Microbial penetration along the implant components of the Brånemark system. An in vitro study. Clin Oral
14. Guindy JS, Besimo CE, Besimo R, Schiel H, Meyer J. Bacterial leakage into and from prefabricated screw-retained implant-borne crowns in vitro. J Oral Rehabil 1998;25(6):403-408.
15. Besimo CE, Guindy JS, Lewetag D, Meyer J. Prevention of bacterial leakage into and from prefabricated screw-retained crowns on implants in vitro. Int J Oral Maxillofac Implants 1999;14(5):654-656.
16. Piattelli A, Scarano A, Paolantonio M, et al: Fluids and microbial penetration in the internal part of cement-retained versus screw-retained implant–abutment connections. J Periodontol 2001;72:1146-1150.
17. Duarte AR, Rossetti PH, Rossetti LM, Torres SA, Bonachela WC. In vitro sealing ability of two materials at five different implant-abutment surfaces. J Periodontol 2006;77(11):1828-1832.
18. Barbosa RE, do Nascimento C, Issa JP, Watanabe E, Ito IY, de Albuquerque RF Jr. Bacterial culture and DNA Checkerboard for the detection of internal contamination in dental implants. J Prosthodont 2009;18(5):376-381.
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20. do Nascimento C, Barbosa RE, Issa JP, Watanabe E, Ito IY, de Albuquerque Junior RF. Use of checkerboard DNA-DNA hybridization to evaluate the internal contamination of dental implants and comparison of bacterial leakage with cast or pre-machined abutments. Clin Oral Implants Res 2009;20(6):571-577.
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25. Koutouzis T, Wallet S, Calderon N, Ludgren T. Bacterial colonization of the implant-abutment interface using an in vitro dynamic loading model. J Periodontol 2011;82(4):613-8.
26. do Nascimento C, Miani PK, Watanabe E, Pedrazzi V, de Albuqerque RF Jr. In vitro evaluation of bacterial leakage along the implant-abutment interface of an external-hex implant after saliva incubation. Int J Oral Maxillofac Implants 2011;26(4):782-7.
27. Coelho PG, Sudack P, Suzuki M, Kurtz KS, Romanos GE, Silva NR. In vitro evaluation of the implant abutment connection sealing capability of different implant systems. J Oral Rehabil 2008;35(12):917-924.
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30. Todescan FF, Pustiglioni FE, Imbronito AV, Albrektsson T, Gioso M. Influence of the microgap in the peri-implant hard and soft tissues: a histomorphometric study in dogs. Int J Oral Maxillofac Implants 2002;17(4):467-72.
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" "
Table 1. Inclusion and exclusion criteria of the study
Inclusion and exclusion criteria of in vitro studies
Inclusion Exclusion
Appeared full text in an English language peer-reviewed journal
In vitro microleakage tests in implant-abutment interface
Papers published between 1990 and 2011
Clinical microleakage evaluations. In vitro microleakage tests having
used implants are not used in dental rehabilitation
Table 2. Results of the in vitro studies
References System n Results
Quirynen et al. 199413 EH (Nobel Biocare) 8 All assemblies
Jansen et al. 19974 EH (Branemark; IMZ), IC
(Ankylos; Astra; Bonefit; Bonefit Octa), IH (IMZ, Semados), IH
with silicon washer (Frialit/ Hermetics); Spline (Calcitek)
Depending for the group
All systems had a leakage, although not 100% of the assemblies
Guindy et al. 199814 IH (HaTi) 10 E/I: All assemblies
I/E: All assemblies
Besimo et al. 199915 IH (HaTi) 30 E/I: 1 assemblies
I/E: No assemblies
Gross et al. 19997 EH (Nobel Biocare; Sterioss, 3i ),
Spline (Sulzer Calcitek), IC (ITI)
3 All assemblies
Piatelli et al. 200116 EH (Bone system, 3i) 6 Cement retained abutment: No
assemblies. Screw retained abutment: All
assemblies
Dibart et al. 20058 IC (Bicon) E/I: 10
I/E: 9
E/I: No assemblies I/E: No assemblies
Steinebrunner et al. 20056 EH (Nobel Biocare), IH (Frialit;
Screw vent), Trilobe (Replace – Nobel Biocare), Camlog
8 All systems and assemblies
Duarte et al. 200617 EH, IH (Neodent and Conexão) 10 All systems and assemblies
Pappalardo et al. 200722 Abutment screwed
(Sweden-Matina Itália), IC (Bicon)
4 Some abutment screwed systems
Coelho et al. 200827 Intra-Lock (Intralock), IC
(Straumann), Trilobe (Replace)
5 22% IL, 55% IC, 100% Trilobe
Do Nascimento et al. 20089 EH (Sin)
Castable Abut. 10 10% assemblies Do Nascimento et al. 2009a19 EH (Sin) Castable Abut.
20 1 Tight: 15% of the assemblies 2 Tight – 35% of the assemblies
Do Nascimento et al. 2009b20
EH (Sin) Pilar Cr-Co e Plástico
9 1 assemblie from each group
Barbosa et al. 200918 EH (Sin)
Castable Abut.
20 30% of the assemblies
Tesmer et al. 200923 IC and IC with a grove (Ankylos),
Trilobe (Nobel)
10 None of the IC; 100% of the IC with a grove and 90% of the trilobe
assemblies
Harder et al. 201010 IC (Ankylos and Astra) 8 1 assemblie from AstraTech group
Aloise et al. 201021 IC (Bicon and Ankylos ) 10 20% of the assemblies
assemblies
Koutouzis et al. 201125 IC (Ankylos and Straumann Bone
Level)
14 7% for Ankylos and 85% for Straumann system
Nascimento et al. 201126 EH (SIN) 12 All assemblies
Table"3."Methodological"aspects"of"the"in"vitro"studies."
References Evaluation Method
Volume*/ Torque (Ncm)/ Immersion
Follow-up Microleakage type Fixed Method
Quirynen et al. 199413 E/I 10 Ncm / PI and CI 7 days Oral Bacteria U
Jansen et al. 19974 I/E 0.5µL/MR/PI 14 days 1 x 108 CFU/mL
E. coli
Pliers
Guindy et al. 199814 E/I
I/E MR/3 mL 2 µL/MR/3mL 5 days 8 x 108 CFU/mL S. aureus U
Besimo et al. 199915 E/I*
I/E MR/4 mL 2 µL 11 weeks 7 days 8 x 108 CFU/mL S. aureus U
Gross et al. 19997 E/I 10, 20Ncm and MR/CI 5, 20 e 80min Gentian Violet U
Piatelli et al. 200116 E/I Dye: MR/CI;
Bacterial: 20 µL/MR/PI 30 h; 72 h Toluidine Blue; 1 x 108 CFU/mL P. aeruginosa U
Dibart et al. 20058 E/I
I/E MR/5 mL 0.1µL/MR/CI 24h 72h A.actinomycetemcomits; S. oralis; F. nucleatum;
2% of the initial broth Mixture of bacteria
Forceps
Steinebrunner et al. 20056 I/E 5 µL/MR/PI 1.200.000
cycles
1.5 x 109 CFU/mL E. coli
U
Duarte et al. 200617 E/I 20 Ncm/4mL 63 days 4x43x109 CFU/mL
S. faecalis
Forceps
Pappalardo et al. 200722 E/I 5 mL/U/PI 72hs S.aureus; E. coli; P.
aeruginosa; S. pyogenes
U
Coelho et al. 200827 I/E 0,7µL/MR/PI 7 days Toluidine Blue Vise
do Nascimento et al. 20089 I/E 3µL/32Ncm/CI 14 days 1 x 108 CFU/mL F. nucleatum
Pliers
do Nascimento et al. 2009a19
E/I 32Ncm/CI 14 days 1 x 108 CFU/mL
S. mutans
Pliers
do Nascimento et al. 2009b20
I/E 3µL/32Ncm/CI 14 days 3 x 105 CFU/mL
S. sobrinus
Pliers
Barbosa et al. 200918 I/E 3µL/32Ncm/CI 14 days 1 x 108 CFU/mL F. nucleatum
Pliers
Tesmer et al. 200923 E/I U/MR/PI 5 days 1:10 dilution of a 1:1 stock
solution
A. actinomycetemcomitans, P. gengivalis Harder et al. 201010 I/E 0.5µL/MR/CI 7 days Lipopolissacarídeo de
Salmonela enterica
Forceps
Aloise et al. 201021 I/E 0.1 µL/MR/CI 14 days 2.41 x 106 CFU/mL
S. sanguinis II Vise
Teixeira et al. 201124 E/I
I/E 4mL/MR/CI 0.5 and 2.0µL/MR/CI 14 days 7 days 1 x 108 CFU/mL S. aureus Pliers
Koutouzis et al. 201125 E/I U/MR/CI 500.000
cycles
1:100 dilution
E. coli U
do Nascimento et al. 201126
E/I 200µL/MR/CI 7 days Saliva Pliers
Capítulo 2
2Bacterial microleakage at the implant-abutment interface in Morse taper implants inoculated with different volumes
João Paulo da Silva-Neto, DDS, MSD, PhD student - Department of Prosthodontics and
Periodontology, University of Campinas, Piracicaba Dental School, Piracicaba, Brazil
Marina de Freitas Majadas, DDS, MSc Student - Department of Occlusion, Fixed
Prostheses, and Dental Materials, Federal University of Uberlândia, School of Dentistry, Uberlândia, Brazil
Marcel Santana Prudente - DDS, MSc Student, DDS Program, Federal University of
Uberlândia, School of Dentistry, Uberlândia, Brazil
Thiago de Almeida Prado Naves Carneiro - DDS, MSc Student, Department of
Occlusion, Fixed Prostheses, and Dental Materials, Federal University of Uberlândia, School of Dentistry, Uberlândia, Brazil
Mario Paulo Amante Penatti, BDS, MSc, PhD - Healthy Technical School, Federal
University of Uberlândia, Uberlândia, Brazil.
Flávio Domingues das Neves, DDS, MSc, PhD - Associate Professor, Department of
Occlusion, Fixed Prostheses, and Dental Materials, Federal University of Uberlândia, School of Dentistry, Uberlândia, Brazil
Mauro Antônio de Arruda Nóbilo, DDS, MSc, PhD - Titular Professor, Department of
Prosthodontics and Periodontology, University of Campinas, Piracicaba Dental School, Piracicaba, Brazil
Correspondence to: Dr. João Paulo da Silva Neto, Piracicaba Dental School, University
of Campinas – Department of Prosthodontics and Periodontics, Av. Limeira, 901 Piracicaba SP 13414-903, Brazil. Phone: +55 (19) 2106-5350; email: [email protected]
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Este capítulo foi submetido ao The Journal of Oral implantology e encontra-se em processo deBacterial microleakage at the implant-abutment interface in Morse taper implants inoculated with different volumes
Abstract
The aim of this study was to evaluate the bacterial microleakage in the implant-abutment interface (I-A) of Morse tapered implants inoculated with different volumes. Morse tapered implants and abutments were selected and assigned into two groups depending on the type abutment: passing screw abutment (PS) and solid abutment (S), and then further subdivided into four subgroups depending on the volume of inoculation in the inner parts of the implant (n=6): PS1: 0.1µL; PS3: 0.3µL; PS5:0.5µL; PS7: 0.7µL; S1: 0.1µL; S3: 0.3µL; S5: 0.5µL e S7: 0.7µL. For the control group, the presence of external contamination was assessed. A bacterial suspension was inoculated in the implants and incubated for microbiological analysis. The microleakage was evaluated every 24 hours during 7 days. After this period, the implants were disassembled for confirmation of the bacterial viability. All the specimens inoculated with 0.7 µL and one sample of the S5 group presented turbidity in the control group after the first 24 hours and were excluded of the study. During the seven days, none of the specimens presented positive results for microleakage and the bacterial viability was confirmed in all evaluated specimens. The volumes 0.1, 0.3, and 0.5 µL did not present bacterial microleakage in the I-A interface. However, the volumes of 0.1 and 0.3 µL may be insufficient to analyze; the volume of 0.7 µL is excessive and could lead to false results of microleakage. The volume of 0.5 µL showed to be closer to the ideal for both evaluated specimens.
Key words: dental implants; Implant-abutment interface; microleakage; Morse taper
