Avaliação Radiográfica de Ajuste Passivo em Estruturas Implanto-Suportadas

Risk factors of peri-implant pathology

“… Patient‐related health status: classification of comorbidities according to the American Society of Anesthesiologists (ASA) (ASA I‐III) ; history of head and neck irradiation in the previous 6 months; history of chemotherapy in the previous 6 months; smoking habits (non‐smoker or smoker); history of periodontitis (periodontitis before rehabilitation with the implant or tooth loss caused by periodontitis); postmenopausal hormone replacement therapy. Implant location in bone and associated characteristics: jaw (mandible or maxilla); position within the jaw (anterior or posterior); implant orientation (axial or tilted); proximity of the implant to teeth or other implants (absence or presence of a natural tooth or implant). Characteristics of the restoration : implant length (7, 8.5, 10, 11.5, 13, 15, or 18 mm); implant diameter (3.3–3.5, 3.75–4.3, or 5–6 mm); implant surface (machined or oxidized); cantilevers (none or ≥1); implant : crown ratio (2:1 or 1:1); type of abutment (straight, angulated 17°, or angulated 30°); abutment height (1–5 mm); type of prosthetic restoration (single tooth, fixed partial restoration, or fixed total restoration); type of material used in the restoration (ceramic, metal–ceramic, metal–acrylic, or acrylic); fracture of prosthetic components within the year prior to diagnosis; lack of prosthetic fit or non‐optimal screw joint (defined as loosening of the prosthetic screw or the visible gap between prosthetic components, evaluated through the ‘one‐screw’ test, together with a periapical radiograph at the time of diagnosis) within the previous year of diagnosis. Technique for implant placement: implants in grafted bone; in post‐extraction sockets; in periodontally compromised sites; phasing of implant restoration (two‐stage: insertion of the implant in the first surgical procedure, followed by a healing period of 4–6 months, and abutment connection in the second surgical procedure; one‐stage: implant and abutment insertion during the same surgical procedure; or immediate function: implant and abutment insertion, and connection of the restoration on the same day of surgery). Clinical parameters : presence of bacterial plaque based on the modified plaque index ; presence of bleeding based on the modified bleeding index (mBI) ; and bone level (located on the coronal, or medium thirds of the implant); information on all parameters were obtained at the clinical appointment that preceded the reference date for cases and controls. Patient compliance: time, in months, between clinical evaluation appointments in the previous year (1–3, 3–5, 6, or >6 months). The dependent variable considered in this study was peri‐implant pathology, defined as follows: the presence of peri‐implant pockets ≥5 mm ; bleeding on probing ; concurrent presence of vertical bone loss visible in the periapical radiograph compared with the previous evaluation ; and attachment loss of ≥2 mm compared with the previous evaluation . …”

Influence of Mismatching Between Prosthetic Components and Dental Implants: An in Vitro Study

“…The impact of abutment rotation and angulation on marginal adaptation is reflected in the misfit of prostheses on implants (Semper et al, 2010). Sousa et al (2010) published a research that studied the observer's experience in the diagnostic capability of implant-supported metal structures with different degrees of maladaptation, through the analysis of digital radiographs taken at different angles. Even though they were apparently fully adjusted, all the prostheses on implants showed micro cracks imperceptible to the human eye.…”

Métodos de exames por imagem utilizados no diagnóstico de desadaptação entre implante e componente protético: uma revisão de literatura

“…17,18 Nesse sentido, alguns autores arriscaram definir um nível clinicamente tolerável dessa desadaptação, o qual não gere respostas biomecânicas indesejáveis. De acordo com Hecker e Eckert 19 e Sousa et al, 20 Brånemark foi o primeiro a definir a adaptação passiva, propondo que deveria existir um nível de desadaptação não superior a 10 µm para permitir a maturação e remodelação óssea em resposta às forças oclusais. Já Klineberg e Murray 21 sugeriam que desadaptações superiores a 30 µm em mais de 10% da circunferência da interface implante/componente protético eram inaceitáveis.…”

“…Portanto, quanto mais próximo da posição ortogonal, mais fiel será a imagem obtida do objeto em questão, e angulações superiores a 5° impossibilitam o diagnóstico correto de possíveis desadaptações de cerca de 10 µm. Se considerarmos Hecker e Eckert 19 e Sousa et al, 20 esse nível de desadaptação já é clinicamente inaceitável. Mas para Jemt e Book, 22 que tolera desadaptações de até 111 µm, variações no ângulo vertical de até 15º, apesar de ocultarem desadaptações tão importantes quanto as superiores 51 µm, podem ser toleradas.…”