Influência de diferentes pilares e materiais de recobrimento estético na manutenção da pré-carga do parafuso de retenção de coroas implantosuportadas

Pós-graduação em Odontologia - FOA

Estudo do desajuste angular e vertical em próteses fixas implantossuportadas por meio do MEF-3D

Pós-graduação em Odontologia - FOA

Estudo in vitro das micro deformações ao redor de implantes suportes de próteses parciais fixas submetidos à cargas axiais e não axiais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Use of Stress Analysis Methods to Evaluate the Biomechanics of Oral Rehabilitation With Implants

Because the biomechanical behavior of dental implants is different from that of natural tooth, clinical problems may occur. The mechanism of stress distribution and load transfer to the implant/bone interface is a critical issue affecting the success rate of implants. Therefore, the aim of this study was to conduct a brief literature review of the available stress analysis methods to study implant-supported prosthesis loading and to discuss their contributions in the biomechanical evaluation of oral rehabilitation with implants. Several studies have used experimental, analytical, and computational models by means of finite element models (FEM), photoelasticity, strain gauges and associations of these methods to evaluate the biomechanical behavior of dental implants. The FEM has been used to evaluate new components, configurations, materials, and shapes of implants. The greatest advantage of the photoelastic method is the ability to visualize the stresses in complex structures, such as oral structures, and to observe the stress patterns in the whole model, allowing the researcher to localize and quantify the stress magnitude. Strain gauges can be used to assess in vivo and in vitro stress in prostheses, implants, and teeth. Some authors use the strain gauge technique with photoelasticity or FEM techniques. These methodologies can be widely applied in dentistry, mainly in the research field. Therefore, they can guide further research and clinical studies by predicting some disadvantages and streamlining clinical time.

Forced orthodontic eruption for augmentation of soft and hard tissue prior to implant placement

Forced orthodontic eruption (FOE) is a non-surgical treatment option that allows modifying the osseous and gingival topography. The aim of this article is to present a clinical case of a FOE, which resulted in an improvement of the amount of available bone and soft-tissues for implant site development. Patient was referred for treatment of mobility and unesthetic appearance of their maxillary incisors. Clinical and radiographic examination revealed inflamed gingival tissue, horizontal and vertical tooth mobility and interproximal angular bone defects. It was chosen a multidisciplinary treatment approach using FOE, tooth extraction, and immediate implant placement to achieve better esthetic results. The use of FOE, in periodontally compromised teeth, promoted the formation of a new bone and soft-tissue in a coronal direction, without additional surgical procedures, enabling an esthetic, and functional implant-supported restoration.

Carga imediata em implantes unitários: revisão da literatura

The possibilities of treatment with dental implants have revolutionized the field of oral rehabilitation in recent years, bringing a number of advantages over conventional prostheses. For years, a surgical protocol was followed that called for maintaining the implant without load for a certain period for osseointegration, but experimental studies have shown that immediate loading of implants also leads to the formation of peri-implant bone tissue along the time, similarly to that observed for conventionally loaded implants. This study aimed to conduct a literature review regarding the use of this alternative rehabilitation with single implants. The immediate loading of single-tooth replacements is presented as an excellent treatment alternative.

Associação de prótese fixa, implantes e estética periodontal para reabilitação de pacientes parcialmente edêntulos

Periodontitis is a chronic inflammatory disease that results in the destruction of teeth and their supporting tissues with subsequent tooth loss. The replacement of missing teeth for implant-supported restorations has proven to be a highly predictable treatment method with good long-term prognosis. However, some consequences of tooth loss prevents dental implant placement in an ideal position, where regenerative procedures are necessary for this type of rehabilitation. Less invasive procedures such as conventional prosthesis emerge as a therapeutic option in cases where there is enough bone structure for implants and patient´s non-acceptance for invasive procedures. Thus, this paper aims to present the resolution of rehabilitation through a noninvasive and multidisciplinary treatment. One female patient referred to the clinic presented maladaptive bilateral mandibular fixed prostheses, endodontic lesions, gingival recession, and root sensitivity. For proper resolution of this case, an association among osseointegrated implants, fixed partial prosthesis, tooth extraction, and aesthetic periodontal procedures with the use of subepithelial connective tissue graft was proposed. After two years, the patient shows excellent aesthetics and chewing. Within the limits of this scenario, this paper discusses the various factors that may affect the choice of a particular treatment modality for the rehabilitation of edentulous single spaces.

Análise estrutural e fadiga em prótese implanto-suportada unitária através do método dos elementos finitos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biomechanical influence of crown-to-implant ratio on stress distribution over internal hexagon short implant: 3-D finite element analysis with statistical test

The study of short implants is relevant to the biomechanics of dental implants, and research on crown increase has implications for the daily clinic. The aim of this study was to analyze the biomechanical interactions of a singular implant-supported prosthesis of different crown heights under vertical and oblique force, using the 3-D finite element method. Six 3-D models were designed with Invesalius 3.0, Rhinoceros 3D 4.0, and Solidworks 2010 software. Each model was constructed with a mandibular segment of bone block, including an implant supporting a screwed metal-ceramic crown. The crown height was set at 10, 12.5, and 15 mm. The applied force was 200 N (axial) and 100 N (oblique). We performed an ANOVA statistical test and Tukey tests; p < 0.05 was considered statistically significant. The increase of crown height did not influence the stress distribution on screw prosthetic (p > 0.05) under axial load. However, crown heights of 12.5 and 15 mm caused statistically significant damage to the stress distribution of screws and to the cortical bone (p <0.001) under oblique load. High crown to implant (C/I) ratio harmed microstrain distribution on bone tissue under axial and oblique loads (p < 0.001). Crown increase was a possible deleterious factor to the screws and to the different regions of bone tissue. (C) 2014 Elsevier Ltd. All rights reserved.

The effect of offset implant configuration on bone stress distribution: a systematic review

Purpose: The aim of this systematic review was to compare straight-line and offset implant configurations for three-element implant-retained prostheses. Materials and Methods: Two independent reviewers conducted a review on PubMed/Medline, EMBASE, and Cochrane Library for studies published in English, from January 1, 1995 to January 17, 2014. A systematic review was conducted following the PRISMA statement. All relevant titles were selected according to inclusion/exclusion criteria. From this pool of titles, abstracts and full texts were reviewed. Results: A total of 6080 titles were identified with the initial search. Twenty-one were selected based on title and abstract. Of these, after discussion and complete reading, 12 studies were selected according to the inclusion and exclusion criteria, all of which were in vitro studies. Conclusions: A systematic review of the current literature showed only in vitro evidence that there is no consensus on the advantage of using an offset configuration implant compared to those in straight-line configuration, even though some studies present a slight improvement of bone stress distribution when an offset implant is under oblique loading (PICO).

Effect of the parafunctional occlusal loading and crown height on stress distribution

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

An esthetics rehabilitation with computer-aided design/ computer-aided manufacturing technology

This paper describes a case of a rehabilitation involving Computer Aided Design/Computer Aided Manufacturing (CAD-CAM) system in implant supported and dental supported prostheses using zirconia as framework. The CAD-CAM technology has developed considerably over last few years, becoming a reality in dental practice. Among the widely used systems are the systems based on zirconia which demonstrate important physical and mechanical properties of high strength, adequate fracture toughness, biocompatibility and esthetics, and are indicated for unitary prosthetic restorations and posterior and anterior framework. All the modeling was performed by using CAD-CAM system and prostheses were cemented using resin cement best suited for each situation. The rehabilitation of the maxillary arch using zirconia framework demonstrated satisfactory esthetic and functional results after a 12-month control and revealed no biological and technical complications. This article shows the important of use technology CAD/CAM in the manufacture of dental prosthesis and implant-supported.

Stress distribution in bone simulation model with pre-angled implants

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

Analysis of the biomechanical behavior of short implants: the photo-elasticity method

The aim of this study was to analyze the stress distribution of short implants supporting single unit or splinted crowns by the photo-elasticity method. Four photo-elastic models were produced: A (3.75×7mm); B (3.75×7mm, 3.75×7mm and 3.75×7mm); C (3.75×10mm, 3.75×7mm and 3.75×7mm); D (3.75×13mm, 3.75×7mm and 3.75×7mm). The prostheses were made with Ni-Cr alloy. A load of 100N in the axial and oblique directions was applied, totaling 380 applications, individually capturing their images in each model. The data were randomized and analyzed qualitatively and quantitatively by 2 examiners. The oblique loading was significantly more damaging. The increase in length was favorable for stress distribution (p<0.05). The splinting was beneficial for the transmission of stresses mainly (p<0.05). The splinting of the crowns, as well as increasing the length of the first implant and axial loading was most beneficial in the stress distribution. Short splinted implants behaved better than single unit implants. Increasing of the length of the first implant significantly improved the stress distribution in all analyzed situations.

Aspectos clínicos influentes no planejamento das próteses sobre implantes tipo overdenture e protocolo

The aim of his study was to review the current scientific literature in order to discuss the surgical, prosthetics and psychological/psychosocial aspects during the treatment planning of edentulous patients, when a total fixed prosthesis or overdenture is indicated. To identify studies to take part in this review, a search was conducted for the following databases: PubMed, Dentistry and Oral Sciences Source, Journals@Ovid, SpringerLink, Wiley Online Library, Nature (NPG), Oxford Journals. It was used as descriptors: total fixed prostheses and overdentures. Inclusion criteria were: clinical articles, clinical case reports, case series, literature reviews and systematic reviews that addressed the study and comparison of total fixed prostheses and overdentures for a surgical- prosthetic planning. Exclusion criteria were: laboratory and in vitro studies and those whose first language was not English or Portuguese. Of a total of 454 articles, after an analysis according to inclusion and exclusion criteria, 76 articles were selected. During an implantsupported prosthesis rehabilitation with dental in edentulous patients, the use of alternative procedures appear to be effective when compared to more invasive surgical techniques, and thus, the amount of dental implants possible to install associated with prosthetic issues such as lip support, smile line, quantity and quality of mucosa, phonetics, etc., will allow an appropriate treatment planning to each clinical case