Background: The screw and cement-retained implant-supported fixed prosthesis has advantages and disadvantages. However, current research comparing the properties of these restorations is lacking. Objectives: The aim o...Background: The screw and cement-retained implant-supported fixed prosthesis has advantages and disadvantages. However, current research comparing the properties of these restorations is lacking. Objectives: The aim of the study was to review the current literature on the properties of screw and cement retained implant supported restorations. Material and Methods: A literature search was conducted from January 2010 to December 2023, using 4 databases to identify research. Sixty studies met the inclusion criteria. Results: Cement-retained restorations have some advantages. Passive fit is easier to achieve, and eliminating occlusal access holes can help with the occlusal adjustments in cemented restorations. However, in case residual cement is not completely removed after cementation, it becomes a predisposing factor for peri-implantitis and marginal bone loss. The main advantage of screw-retained restorations is the retrievability, which can be achieved without damaging the restoration or fixture. However, in case the implant is not ideally positioned, the location of the screw access channel can negatively affect the aesthetics of the screw-retained restorations. In addition, porcelain fracture and screw loosening occur more frequently in screw-retained restoration. Conclusions: Screw and cement-retained restorations display specific advantages and disadvantages;nevertheless, the selection of one retention method over another depends on the clinical scenario.展开更多
Metal-ceramic restorations are widely used in dentistry with a high degree of general success. However, fracture of these restorations does occur and usually frustrates both the dentist and the patient. Objective: Thi...Metal-ceramic restorations are widely used in dentistry with a high degree of general success. However, fracture of these restorations does occur and usually frustrates both the dentist and the patient. Objective: This literature review discusses the factors that may lead to the fracture of these restorations whether they are tooth-supported or implant-supported with the aim of making dentists and technicians aware of these factors to avoid them. Factors reviewed include: technical factors, dentist-related factors, inherent material properties, direction, magnitude and frequency of applied loads, environmental factors, screw-retained implant-supported restorations, and posterior cantilevered prostheses. Material and Methods: A netbased search in “Pubmed” was performed and combined with a manual search. The search was limited to articles written in English. Conclusions: the published literature revealed that the factors predisposing to fracture of metal-ceramic restorations may be related to the technician, dentist, patient, environment, design of the restoration, or to inherent structure of ceramics and others. However, if the dentist and technician understand these factors and respect the physical characteristics of the materials, most of those are avoidable.展开更多
Open oro-nasal defects resulting after oral tumor resection need structural and functional rehabilitation using dental prostheses. Conventional removable prostheses have usually been indicated and performed for prosth...Open oro-nasal defects resulting after oral tumor resection need structural and functional rehabilitation using dental prostheses. Conventional removable prostheses have usually been indicated and performed for prosthodontics. When the patient has an edentulous maxilla, the unfavorable stability of the prosthesis will cause dysfunction of mastication and pronunciation. To achieve improvement of the impaired functional situation, implant-supported full fixed prostheses (IPSPs) for the edentulous maxilla with a removable obturator offer a reasonable solution. We present herein the case of a 70-year-old Japanese man who has presented with oro-nasal defect due to surgical procedures for oral cancer. He was treated with implant-supported full fixed prostheses in a conventional two-step procedure. After prosthesis treatment, a palatal obturator was set. The patient has shown no clinical or radiological evidence of failure as of 24 months after the end of treatment. Functional evaluation of mastication and pronunciation showed dramatic improvements. For a patient with an edentulous maxilla and palatal fistula, full-arch fixed prostheses supported by a combination of axially and non-axially positioned implants and a removable oro-nasal obturator, using the anterior alveolar bone, without bone transplantation or maxillary sinus elevation, could offer an effective, minimally invasive treatment alternative.展开更多
Provisional prosthetic restoration materials are exposed to oral cavity producing on the surface biofilm where different factors such as surface roughness and porosity can condition their formation and organization an...Provisional prosthetic restoration materials are exposed to oral cavity producing on the surface biofilm where different factors such as surface roughness and porosity can condition their formation and organization and can create stagnation areas that promote the bonding of organic particles, thus facilitating the formation and maturation of the biofilm. The purpose of this study was to compare surface roughness of two provisional prosthetic restorations materials and their bacterial susceptibility. In this study, two provisional restoration materials were used in two groups, A polymethyl methacrylate acrylic (NicTone MDC DENTAL) and B bis-acryl resin (Protemp 4 ESPE 3M). A total of 80 samples (40 samples of each material) were in thick plates of 10 × 10 mm and 2 mm high. 20 samples of each material were polished, while 20 were left unpolished. Subsequently, the samples were observed by Atomic Force Microscopy for their evaluation of surface roughness. The values were analyzed with t-test, Mann-Whitney U test and Kruskal Wallis test. The samples were microbiologically inoculated with the strains obtained and identified from a provisional polymethyl methacrylate acrylic restoration in a patient, in order to observe bacterial adhesion using a Scanning Electron Microscope. Two strains, Enterococcus faecalis and Pseudomona luteola, were identified. The presence of the microorganisms was observed on the surface of both materials, either polished or unpolished, with a lower level of microorganism adhesion found on the bis-acrylic resin. There was a significant difference about surface roughness in the groups A and B with p -8). We found that the polished bis-acrylic resin showed lower surface roughness and bacterial adhesion in comparison with the polymethyl methacrylate.展开更多
文摘Background: The screw and cement-retained implant-supported fixed prosthesis has advantages and disadvantages. However, current research comparing the properties of these restorations is lacking. Objectives: The aim of the study was to review the current literature on the properties of screw and cement retained implant supported restorations. Material and Methods: A literature search was conducted from January 2010 to December 2023, using 4 databases to identify research. Sixty studies met the inclusion criteria. Results: Cement-retained restorations have some advantages. Passive fit is easier to achieve, and eliminating occlusal access holes can help with the occlusal adjustments in cemented restorations. However, in case residual cement is not completely removed after cementation, it becomes a predisposing factor for peri-implantitis and marginal bone loss. The main advantage of screw-retained restorations is the retrievability, which can be achieved without damaging the restoration or fixture. However, in case the implant is not ideally positioned, the location of the screw access channel can negatively affect the aesthetics of the screw-retained restorations. In addition, porcelain fracture and screw loosening occur more frequently in screw-retained restoration. Conclusions: Screw and cement-retained restorations display specific advantages and disadvantages;nevertheless, the selection of one retention method over another depends on the clinical scenario.
文摘Metal-ceramic restorations are widely used in dentistry with a high degree of general success. However, fracture of these restorations does occur and usually frustrates both the dentist and the patient. Objective: This literature review discusses the factors that may lead to the fracture of these restorations whether they are tooth-supported or implant-supported with the aim of making dentists and technicians aware of these factors to avoid them. Factors reviewed include: technical factors, dentist-related factors, inherent material properties, direction, magnitude and frequency of applied loads, environmental factors, screw-retained implant-supported restorations, and posterior cantilevered prostheses. Material and Methods: A netbased search in “Pubmed” was performed and combined with a manual search. The search was limited to articles written in English. Conclusions: the published literature revealed that the factors predisposing to fracture of metal-ceramic restorations may be related to the technician, dentist, patient, environment, design of the restoration, or to inherent structure of ceramics and others. However, if the dentist and technician understand these factors and respect the physical characteristics of the materials, most of those are avoidable.
文摘Open oro-nasal defects resulting after oral tumor resection need structural and functional rehabilitation using dental prostheses. Conventional removable prostheses have usually been indicated and performed for prosthodontics. When the patient has an edentulous maxilla, the unfavorable stability of the prosthesis will cause dysfunction of mastication and pronunciation. To achieve improvement of the impaired functional situation, implant-supported full fixed prostheses (IPSPs) for the edentulous maxilla with a removable obturator offer a reasonable solution. We present herein the case of a 70-year-old Japanese man who has presented with oro-nasal defect due to surgical procedures for oral cancer. He was treated with implant-supported full fixed prostheses in a conventional two-step procedure. After prosthesis treatment, a palatal obturator was set. The patient has shown no clinical or radiological evidence of failure as of 24 months after the end of treatment. Functional evaluation of mastication and pronunciation showed dramatic improvements. For a patient with an edentulous maxilla and palatal fistula, full-arch fixed prostheses supported by a combination of axially and non-axially positioned implants and a removable oro-nasal obturator, using the anterior alveolar bone, without bone transplantation or maxillary sinus elevation, could offer an effective, minimally invasive treatment alternative.
文摘Provisional prosthetic restoration materials are exposed to oral cavity producing on the surface biofilm where different factors such as surface roughness and porosity can condition their formation and organization and can create stagnation areas that promote the bonding of organic particles, thus facilitating the formation and maturation of the biofilm. The purpose of this study was to compare surface roughness of two provisional prosthetic restorations materials and their bacterial susceptibility. In this study, two provisional restoration materials were used in two groups, A polymethyl methacrylate acrylic (NicTone MDC DENTAL) and B bis-acryl resin (Protemp 4 ESPE 3M). A total of 80 samples (40 samples of each material) were in thick plates of 10 × 10 mm and 2 mm high. 20 samples of each material were polished, while 20 were left unpolished. Subsequently, the samples were observed by Atomic Force Microscopy for their evaluation of surface roughness. The values were analyzed with t-test, Mann-Whitney U test and Kruskal Wallis test. The samples were microbiologically inoculated with the strains obtained and identified from a provisional polymethyl methacrylate acrylic restoration in a patient, in order to observe bacterial adhesion using a Scanning Electron Microscope. Two strains, Enterococcus faecalis and Pseudomona luteola, were identified. The presence of the microorganisms was observed on the surface of both materials, either polished or unpolished, with a lower level of microorganism adhesion found on the bis-acrylic resin. There was a significant difference about surface roughness in the groups A and B with p -8). We found that the polished bis-acrylic resin showed lower surface roughness and bacterial adhesion in comparison with the polymethyl methacrylate.
