ABSTRACT
El objetivo de esta revisión sistemática fue evaluar los distintos diseños en el cuello del implante (pulido o tratado, con o sin intercambio de plataforma, o con o sin microespiras) y su posible influencia en la pérdida del hueso marginal periimplantario. Se llevo a cabo una revisión sistemática siguiendo la metodología PICO del Centro de Medicina Basada en la Evidencia de la Universidad de Oxford. La pregunta dirigida a la consecución de los objetivos fue: ¿Es el diseño del cuello del implante un factor crítico en la conservación del hueso marginal periimplantario? Se emplearon MeSH keywords específicos en las bases de datos Pubmed y Cochrane. Tres revisores independientes se pusieron de acuerdo en los estudios finalmente incluidos, obteniendo un índice de concordancia kappa de 0,88. De estos, se realizó una evaluación crítica del nivel de evidencia y también del riesgo de sesgo de los RCT mediante la Herramienta Cochrane. Se consultaron 445 artículos por título, incluyendo finalmente un total de 16 artículos a texto completo. La heterogeneidad de estos estudios impidió realizar un meta-análisis. No se encontró evidencia de que una determinada configuración del cuello del implante sea mejor que otra en la conservación del hueso marginal periimplantario y sin embargo, parece que una posición apico-coronal yuxtaósea del cuello pulido del implante respecto a la cresta ósea receptora pudiera ser crítica a ese respecto. No se encontró suficiente evidencia sobre la efectividad de las diferentes configuraciones de la región cervical del implante en la preservación del hueso marginal periimplantario. Son necesarios estudios clínicos controlados y aleatorizados a largo plazo para valorar los efectos de dichas modificaciones.
The aim of this systematic review was to assess whether different implant neck designs (polished or coated, with or without platform switching, either with or without microthreads) influence marginal bone resorption. A systematic review was conducted following the PICO methodology of the Centre for Evidence-Based Medicine of Oxford University. The question to the achievement of objectives was: Is the design of the implant neck a critical factor in the preservation of marginal bone levels? Specific MeSH keywords were used in the Pubmed and Cochrane databases. Three independent reviewers agreed on the studies ultimately included finding a concordance kappa index of 0.86. Of these articles, acritical evaluation of the level of evidence was performed and also the risk of bias of the RCT using the Cochrane tool. Four hundred forty-five items were reviewed by title, eventually including a total of 16 full-text articles. Heterogeneity of these studies made impossible the performance of a meta-analysis. No evidence that a particular configuration of the implant neck was better than another in preserving the peri-implant marginal bone was found, and yet it seems that an apico-coronal position juxta-osseous of the smooth neck of the implant relative to the bone crest could be decisive. Not enough evidence was found on the effectiveness of different configurations of the cervical region of the implant in the periimplant marginal bone preservation. More randomized controlled trials are needed to assess long-term effects of such modifications.
Subject(s)
Humans , Alveolar Bone Loss , Dental Implantation , Maxilla , Bone Resorption , Dental Prosthesis Design , Dental Implantation, Endosseous , Peri-ImplantitisABSTRACT
PURPOSE: The peri-implant soft tissue is remodeled by the initial marginal bone resorption affecting the prognosis and esthetic result of treatment. Thus various designs on implant neck design are studied to preserve peri-implant bone. The purpose of this study is to review on the causes of initial marginal bone resorption, the configuration of peri-implant soft tissue, and the implant crestal module favorable in preserving peri-implant tissue. MATERIALS AND METHODS: The studies on the causes of initial marginal bone resorption and the implant crestal modules are researched and reviewed using Pubmed database. The implant crestal modules including one piece and two-piece implant, internal and external hex abutment, taper and butt joint connection, scalloped design abutment, and platform switching concept are reviewed. RESULTS: A number of clinical and experimental studies preferred one piece implant to two-piece in preserving initial peri-implant tissue. For two piece implants, internal hex abutment and taper joint connection appear more favorable than external hex abutment and butt joint connection relatively. Controversial issues still exist on scalloped design requiring more studies on it. Although the rationale is not certain, the concept of platform switching seems favorable in preserving initial peri-implant tissue based on clinical and experimental studies. CONCLUSION: Each implant crestal module contains its own advantages and disadvantages with various controversial issues. In the aspect of preservation of initial peri-implant tissue, however, one-piece implant seems beneficial. In cases when two-piece implant is more appropriate due to prosthodontic concerns or any other problems, the application of platform switching concept, internal connection abutment, and taper joint connection may be favorable for the preservation of peri-implant tissues.
Subject(s)
Bone Resorption , Joints , Neck , Pectinidae , Prognosis , ProsthodonticsABSTRACT
PURPOSE: The purpose of this study was to investigate the effects of the surface morphology of the implant neck on marginal bone stress measured by using finite element analysis in six implant models. MATERIALS AND METHODS: The submerged type rescue implant system (Dentis co., Daegu, Korea) was selected as an experimental model. The implants were divided into six groups whose implant necks were differently designed in terms of height (h, 0.4 and 1.0 mm) and width (platform width, w = 3.34 + 2b [b, 0.2, 0.3 and 0.4 mm]). Finite element models of implant/bone complex were created using an axisymmetric scheme. A load of 100 N was applied to the central node on the top of crown in parallel with the implant axis. The maximum compression stress was calculated and compared. RESULTS: Stress concentration commonly observed around dental implants did not occur in the marginal bone around all six test implant models. Marginal bone stress varied according to the implant neck bevel which had different width and height. The stress was affected more markedly by the difference in height than in width. CONCLUSION: This result indicates that the implant neck bevel may play an important role in improving stress distribution in the marginal bone area.