Bone reformation and implant integration following maxillary sinus membrane elevation: An experimental study in primates

Background: Recent clinical studies have described maxillary sinus floor augmentation by simply elevating the maxillary sinus membrane without the use of adjunctive grafting materials. Purpose: This experimental study aimed at comparing the histologic outcomes of sinus membrane elevation and simultaneous placement of implants with and without adjunctive autogenous bone grafts. The purpose was also to investigate the role played by the implant surface in osseointegration under such circumstances. Materials and Methods: Four tufted capuchin primates had all upper premolars and the first molar extracted bilaterally. Four months later, the animals underwent maxillary sinus membrane elevation surgery using a replaceable bone window technique. The schneiderian membrane was kept elevated by insertion of two implants (turned and oxidized, Brånemark System®, Nobel Biocare AB, Göteborg, Sweden) in both sinuses. The right sinus was left with no additional treatment, whereas the left sinus was filled with autogenous bone graft. Implant stability was assessed through resonance frequency analysis (Osstell™, Integration Diagnostics AB, Göteborg, Sweden) at installation and at sacrifice. The pattern of bone formation in the experimental sites and related to the different implant surfaces was investigated using fluorochromes. The animals were sacrificed 6 months after the maxillary sinus floor augmentation procedure for histology and histomorphometry (bone-implant contact, bone area in threads, and bone area in rectangle). Results: The results showed no differences between membrane-elevated and grafted sites regarding implant stability, bone-implant contacts, and bone area within and outside implant threads. The oxidized implants exhibited improved integration compared with turned ones as higher values of bone-implant contact and bone area within threads were observed. Conclusions: The amount of augmented bone tissue in the maxillary sinus after sinus membrane elevation with or without adjunctive autogenous bone grafts does not differ after 6 months of healing. New bone is frequently deposited in contact with the schneiderian membrane in coagulum-alone sites, indicating the osteoinductive potential of the membrane. Oxidized implants show a stronger bone tissue response than turned implants in sinus floor augmentation procedures. © 2006 Blackwell Publishing, Inc.

Histological findings following the use of a space-making device for bone reformation and implant integration in the maxillary sinus of primates

Background: Previous studies have shown that membrane elevation results in predictable bone formation in the maxillary sinus provided that implants can be placed as tent poles. In situations with an extremely thin residual crest which impairs implant placement, it is possible that a space-making device can be used under the sinus membrane to promote bone formation prior to placement of implants. Purpose: The present study was conducted to test the hypothesis that the use of a space-making device for elevation of the sinus membrane will result in predictable bone formation at the maxillary sinus floor to allow placement of dental implants. Materials and Methods: Eight tufted capuchin primates underwent bilateral sinus membrane elevation surgery, and a bioresorbable space-making device, about 6 mm wide and 6 mm in height, was placed below the elevated membrane on the sinus floor. An oxidized implant (Nobel Biocare AB, Gothenburg, Sweden) was installed in the residual bone protruding into the created space at one side while the other side was left without an implant. Four animals were sacrificed after 6 months of healing. The remaining four animals received a second implant in the side with a space-making device only and followed for another 3 months before sacrifice. Implant stability was assessed through resonance frequency analysis (RFA) using the Osstell™ (Osstell AB, Gothenburg, Sweden) at installation, 6 months and 9 months after the first surgery. The bone-implant contact (BIC) and bone area inside the threads (BA) were histometrically evaluated in ground sections. Results: Histologically there were only minor or no signs of bone formation in the sites with a space-making device only. Sites with simultaneous implant placement showed bone formation along the implant surface. Sites with delayed implant placement showed minor or no bone formation and/or formation of a dense fibrous tissue along the apical part of the implant surface. In the latter group the apical part of the implant was not covered with the membrane but protruded into the sinus cavity. Conclusions: The use of a space-making device, with the design used in the present study, does not result in bone formation at the sinus floor. However, membrane elevation and simultaneous placement of the device and an implant does result in bone formation at the implant surface while sites with implants placed 6 months after membrane elevation show only small amounts of bone formation. It is suggested that lack of stabilization of the device and/or a too extensive elevation of the membrane may explain the results. © 2009, Wiley Periodicals, Inc.

Além das portarias: desafios da política de saúde mental

O presente trabalho pretende analisar algumas portarias da Política Nacional de Saúde Mental implementadas no país no período de 1990/2006, pois elas se constituíram em importantes dispositivos para induzir mudanças do modelo assistencial na Saúde Mental. Aponta-se para os documentos mais relevantes e destacam-se suas consequências e problemas para a construção da atenção psicossocial. Ao final, conclui-se que o avanço da Reforma Psiquiátrica brasileira não pode ficar descolado de ações no interior do SUS. Dessa forma, os gestores de saúde, ao lado dos demais segmentos da sociedade, passaram a ser atores importantes na utilização dos recursos contidos na nova legislação de fato voltados para a construção de um novo modo de cuidado na saúde mental que possibilite o reposicionamento do sujeito no mundo, considerando-se sua dimensão subjetiva e sociocultural.

Optimal control problem for deflection plate with crack

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A reivenção política do MST: uma análise do programa de reforma agrária do movimento dos trabalhadores rurais sem terra ao longo da sua história

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Mistagogia da música ritual católica romana: estudo teórico-metodológico

Pós-graduação em Música - IA

Reforma do Estado e transformação das elites econômicas e políticas de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Descrição e análise das contingências presentes na proposta de Estatuto da Pessoa com Deficiência

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Trupe Maluko Beleza: percursos e sentidos de uma oficina de teatro no campo da saúde mental

Pós-graduação em Psicologia - FCLAS

Formação de leitores surdos e a educação inclusiva

Pós-graduação em Educação - FFC

Modelagem numérica do terreno na avaliação do volume admissível em canais de cordões de contorno nivelados

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

As Virgens Marias da Nova Espanha e do Arcebispado de Lima durante os séculos XVI e XVII: entre a idolatria e a santidade

Pós-graduação em História - FCHS

Obtenção e estudo de polímeros supramoleculares derivados de ácidos carboxílicos-meglumina em fase aquosa

Pós-graduação em Química - IQ

Entre livres e oficiais: a expansão do ensino normal em São Paulo (1927-1933)

Pós-graduação em Educação - FFC

Os professores e os projetos nas escolas públicas estaduais paulistas: um trabalho possível?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)