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Australian Dental Journal Jun 2011The aim of this study was to review the literature on the restoration of single-tooth implants, and to develop evidence-based conclusions to optimize aesthetic, biologic... (Review)
Review
BACKGROUND
The aim of this study was to review the literature on the restoration of single-tooth implants, and to develop evidence-based conclusions to optimize aesthetic, biologic and patient-related outcomes.
METHODS
An electronic and hand search was conducted using the search terms 'dental implants, single-tooth; dental restoration, temporary; dental impression materials; dental impression technique; dental prosthesis, implant-supported; dental prosthesis design; dental abutments; dental occlusion; maintenance; survival; and survival analysis'. Resultant titles were screened, and full text was obtained where relevant. The authors selected the most appropriate articles, giving preference to systematic reviews and long-term, patient-based outcome data.
RESULTS
Thirty-nine articles were selected and critiqued by the authors.
CONCLUSIONS
There was strong suggestion by several authors that peri-implant soft tissue aesthetics can be sculpted through provisional restoration contour, but there are no clinical outcome studies to define or support this claim. Laboratory studies demonstrate that pick-up type impression copings in conjunction with elastomeric impressions are the most accurate means for transferring implant position to a dental cast. Laboratory and finite-element analysis studies suggest implants with an internal-type connection show improved stress distribution, but supportive clinical data are lacking. The authors of this review favour a screw-retained prosthesis for retrievability. Clinical and histological studies show that gold, titanium and zirconia ceramic abutment materials exhibit excellent biological responses, although there is insufficient data on the clinical service provided by zirconia as an implant-substructure material. The literature does not associate any particular occlusal scheme with superior clinical outcomes. Implant-borne single crowns offer comparable clinical service to tooth-borne fixed dental prostheses. However, single-tooth implant restorations are associated with an increased incidence of biological and technical complications.
Topics: Dental Abutments; Dental Implants, Single-Tooth; Dental Impression Technique; Dental Materials; Dental Occlusion; Dental Prosthesis Design; Dental Prosthesis, Implant-Supported; Dental Restoration, Temporary; Esthetics, Dental; Humans; Treatment Outcome
PubMed: 21623811
DOI: 10.1111/j.1834-7819.2011.01322.x -
Brazilian Dental Journal Jun 2020The objective of this work was to evaluate the effects of in vitro and in situ biodegradation on the surface characteristics of two resin cements and a hybrid ceramic...
The objective of this work was to evaluate the effects of in vitro and in situ biodegradation on the surface characteristics of two resin cements and a hybrid ceramic system. One hundred and eighty specimens (4X1.5mm) of each material (Maxcem Elite, NX3 Nexus and Vita Enamic) were made and randomly distributed in twelve groups (n=15) according to the material and biodegradation method. The specimens were then submitted to the following challenges: storage in distilled water 37 ºC for 24 h or 7 days, storage for 7 days, at 37 ºC, in stimulated saliva or in situ. The in situ stage corresponded to the preparation of 15 intraoral palatal devices, used for 7 days. Each device presented 3 niches, where a sample of each materials was accommodated. Specimens from both saliva and in situ groups suffered a cariogenic challenge, corresponding to the application of a solution of 20% of sucrose, 10 times throughout each day. After each biodegradation method, the surface roughness (Ra), Vickers hardness (VHN) and scanning electron microscopy (SEM) analyzes were performed. The data collected were evaluated by Levene test, two-way ANOVA and Tukey`s test (α=5%). The in situ challenge promoted the greater biodegradation, regardless of the material. Regarding the materials, the Vita Enamic VHN was negatively affected by all biodegradation methods and the Nexus NX3 presented better performance than the self-adhesive cement tested. Therefore, within the conditions of this work, it was concluded that in situ biodegradation can affect negatively the surface characteristics of indirect restorative materials.
Topics: Ceramics; Dental Materials; Hardness; Materials Testing; Resin Cements; Surface Properties
PubMed: 32667515
DOI: 10.1590/0103-6440202002982 -
International Dental Journal Dec 2011Nanotechnology has been used for medical applications in several forms, including dental practice with the development of silver nanoparticles (Ag NPs) as a useful tool.... (Review)
Review
Nanotechnology has been used for medical applications in several forms, including dental practice with the development of silver nanoparticles (Ag NPs) as a useful tool. The aim of this review was to identify the properties and appliances of Ag NPs in dental practice. Silver compounds and NPs have already been used as dental restorative material, endodontic retrofill cements, dental implants and caries inhibitory solution. Despite the effectiveness that Ag NPs has shown in dental practice, Ag NPs remain a controversial area of research with respect to their toxicity in biological and ecological systems. Therefore any application of Ag NPs in dentistry requires more studies. In order to avoid the toxicity of these materials Ag NPs can be temporarily used in dentistry.
Topics: Anti-Infective Agents; Cariostatic Agents; Dental Materials; Humans; Nanoparticles; Silver
PubMed: 22117785
DOI: 10.1111/j.1875-595X.2011.00072.x -
Journal of the American Dental... Dec 2022This narrative review addresses dental restorative materials with sustained antibacterial action, especially those containing quaternary ammonium compounds. Secondary... (Review)
Review
BACKGROUND
This narrative review addresses dental restorative materials with sustained antibacterial action, especially those containing quaternary ammonium compounds. Secondary caries occurs around restorations, causing further loss of mineral and breakdown of the restoration. Lesions adjacent to restorations account for more than 40% of needed restorations. Restorative materials with antibacterial properties will potentially solve this problem.
TYPES OF STUDIES REVIEWED
Several groups are researching composite restorative materials that incorporate antibacterial agents. These agents are mostly exhausted over time. Newer studies involve materials that incorporate antibacterial microparticles that remain active and do not leach out.
RESULTS
One such antibacterial agent, quaternary ammonium coupled with inorganic silica into minute particles (QASi), has been studied in the laboratory and in humans. QASi particles incorporated into dental materials retain their antibacterial action over time without leaching or loss of activity. A clinical in situ study in humans using dental composite containing QASi resulted in highly significantly less demineralization in the adjacent enamel than the control composite material.
CONCLUSIONS AND PRACTICAL IMPLICATIONS
Dental restorative materials that contain QASi have sustained antibacterial properties, have mechanical properties comparable to those of presently marketed materials, and have been cleared by the US Food and Drug Administration. Clinical studies have shown that composites incorporating QASi have the potential to markedly reduce the occurrence of caries around restorations. Because caries around restorations is a major problem, restorative materials with sustained antibacterial properties will have an important effect in reducing secondary caries around restorations.
Topics: Humans; Quaternary Ammonium Compounds; Composite Resins; Dental Caries; Anti-Bacterial Agents; Dental Enamel; Dental Materials; Dental Restoration, Permanent
PubMed: 36272816
DOI: 10.1016/j.adaj.2022.09.006 -
British Dental Journal Nov 2021Sectional matrix techniques offer more predictable solutions to achieving contact areas when placing direct interproximal posterior composites than circumferential...
Sectional matrix techniques offer more predictable solutions to achieving contact areas when placing direct interproximal posterior composites than circumferential matrix techniques, resulting in reduced reported complaints of food packing from patients. Despite this, a large majority of UK dentists and therapists don't currently use them. Sectional matrix systems are technique-sensitive to use, which can be a barrier to implementation for inexperienced users. The matrices can easily distort during their placement and stabilisation and when placing the restorative material. This can result in unwanted, clinically relevant problems in the resulting restorations, some of which may not be discernible once they have occurred. This paper explores the advantages and disadvantages of sectional matrices and the processes and techniques involved in their use, before discussing the potential for distortion at each step. It offers solutions to some of the commonly seen problems which will provide more predictable outcomes for those already using these techniques and encourage non-users to add them to their armamentarium.
Topics: Composite Resins; Dental Cavity Preparation; Dental Materials; Dental Restoration, Permanent; Humans; Matrix Bands
PubMed: 34773017
DOI: 10.1038/s41415-021-3608-5 -
Journal of Dental Research Apr 2011Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material... (Review)
Review
Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance.
Topics: Biocompatible Materials; Chemical Phenomena; Composite Resins; Dental Materials; Dental Restoration, Permanent; Forecasting; Humans; Photochemical Processes; Polymerization; Stress, Mechanical; Surface Properties
PubMed: 20924063
DOI: 10.1177/0022034510381263 -
Surface characterization of indirect restorative materials submitted to different etching protocols.Journal of Dentistry Dec 2022This in vitro study aimed to evaluate the effect of different times and concentrations of hydrofluoric acid etching on the surface of indirect restorative materials...
OBJECTIVES
This in vitro study aimed to evaluate the effect of different times and concentrations of hydrofluoric acid etching on the surface of indirect restorative materials obtained from blocks used in CAD-CAM technology.
METHODS
Specimens (4 mm × 4 mm × 0.8 mm) were obtained for each indirect restorative material: zirconia-reinforced lithium monosilicate ceramic (Celtra Duo), nanoceramic resin (Lava Ultimate), and polymer-infiltrated ceramic network material (Vita Enamic). The materials were submitted to etching with 5% or 10% hydrofluoric acid for 20, 40, 60, or 90 s. A control group for each material was evaluated without any surface treatment, totaling nine experimental groups for each material (n = 10). The specimens were evaluated for surface roughness (R and R), confocal optical microscopy, the contact angle (θ), surface free energy (γs), total free interaction energy (∆G) using a goniometer, and microshear bond strength to resin cement. Specimen images were obtained using scanning electron microscopy, confocal optical microscopy, and atomic force microscopy. Data on the surface roughness, the contact angle, surface free energy, total free interaction energy, and bond strength were subjected to two-way ANOVA and Tukey´s test (α=0.05).
RESULTS
In general, Celtra Duo showed better results after etching with 10% hydrofluoric acid for 40 or 60 s. Lava Ultimate showed better performance after etching with 10% hydrofluoric acid for 20 or 40 s, whereas Vita Enamic showed better results after etching with 5% hydrofluoric acid for 90 s.
CONCLUSION
Each material showed different characteristics after etching with hydrofluoric acid. Knowledge of the proper protocol for each material is essential to ensure improvements in the adhesion process and durability of indirect restorations. In general, Celtra Duo presented mechanical properties superior to those of Lava Ultimate and Vita Enamic.
CLINICAL SIGNIFICANCE
Specific etching protocols must be recommended for each indirect material because longer exposure to hydrofluoric acid can jeopardize the surface, thus affecting the mechanical and bond strength properties.
Topics: Hydrofluoric Acid; Dental Bonding; Dental Porcelain; Materials Testing; Surface Properties; Dental Materials; Resin Cements; Ceramics; Computer-Aided Design
PubMed: 36280006
DOI: 10.1016/j.jdent.2022.104348 -
Influence of inorganic nanoparticles on dental materials' mechanical properties. A narrative review.BMC Oral Health Nov 2023Inorganic nanoparticles have been widely incorporated in conventional dental materials to help in improving their properties. The literature has shown that incorporating... (Review)
Review
Inorganic nanoparticles have been widely incorporated in conventional dental materials to help in improving their properties. The literature has shown that incorporating nanoparticles in dental materials in different specialties could have a positive effect on reinforcing the mechanical properties of those materials; however, there was no consensus on the effectiveness of using nanoparticles in enhancing the mechanical properties of dental materials, due to the variety of the properties of nanoparticles itself and their effect on the mechanical properties. This article attempted to analytically review all the studies that assessed the effect of different types of inorganic nanoparticles on the most commonly used dental materials in dental specialties such as polymethyl methacrylate, glass ionomer cement, resin composite, resin adhesive, orthodontic adhesive, and endodontic sealer. The results had shown that those inorganic nanoparticles demonstrated positive potential in improving those mechanical properties in most of the dental materials studied. That potential was attributed to the ultra-small sizes and unique physical and chemical qualities that those inorganic nanoparticles possess, together with the significant surface area to volume ratio. It was concluded from this comprehensive analysis that while a definitive recommendation cannot be provided due to the variety of nanoparticle types, shapes, and incorporated dental material, the consensus suggests using nanoparticles in low concentrations less than 1% by weight along with a silane coupling agent to minimize agglomeration issues and benefit from their properties.
Topics: Humans; Dental Cements; Dental Bonding; Resin Cements; Composite Resins; Glass Ionomer Cements; Nanoparticles; Materials Testing; Surface Properties; Stress, Mechanical; Dental Materials
PubMed: 37990196
DOI: 10.1186/s12903-023-03652-1 -
International Journal of Molecular... Dec 2023The dental material industry is rapidly developing resin-based composites (RBCs), which find widespread use in a variety of clinical settings. As such, their... (Review)
Review
The dental material industry is rapidly developing resin-based composites (RBCs), which find widespread use in a variety of clinical settings. As such, their biocompatibility has gained increasing interest. This literature review presents a summary of research into the cytotoxicity of methacrylate-based composites published from 2017 to 2023. Subject to analysis were 14 in vitro studies on human and murine cell lines. Cytotoxicity in the included studies was measured via MTT assay, LDH assay, and WST-1 assay. The QUIN Risk of Bias Tool was performed to validate the included studies. Included studies (based entirely on the results of in vitro studies) provide evidence of dose- and time-dependent cytotoxicity of dental resin-based composites. Oxidative stress and the depletion of cellular glutathione (GSH) were suggested as reasons for cytotoxicity. Induction of apoptosis by RBCs was indicated. While composites remain the golden standard of dental restorative materials, their potential cytotoxicity cannot be ignored due to direct long-term exposure. Further in vitro investigations and clinical trials are required to understand the molecular mechanism of cytotoxicity and produce novel materials with improved safety profiles.
Topics: Humans; Animals; Mice; Apoptosis; Biological Assay; Cell Line; Dental Materials; Glutathione
PubMed: 38203323
DOI: 10.3390/ijms25010152 -
Journal of the Mechanical Behavior of... Oct 2021The aim of this study was to investigate whether there is a relation between impact strength and flexural strength of different composite and ceramic materials used in...
AIM
The aim of this study was to investigate whether there is a relation between impact strength and flexural strength of different composite and ceramic materials used in dental restorations.
MATERIALS AND METHODS
The three-point-bending test was used to determine the flexural strength and flexural modulus, and the Dynstat impact test was used to determine the impact strength of different composite and ceramic dental materials. The relation between the flexural strength and impact strength was mathematically investigated and a three-dimensional finite element analysis model of the impact test set-up was created to verify these results.
RESULTS
We found a relation between the impact strength, a, the flexural strength, σ, and the flexural modulus, E, which can be represented by the formula: a=λ(σ⁄E), where λ is a constant dependent on the test set-up.
CONCLUSION
The obtained impact strength of materials is specific to the test set-up and dependent on the geometric configuration of the test set-up and the specimen thickness. The clinical significance of this investigation is that roughness and fatigue have far more influence on the impact strength than the flexure strength.
Topics: Ceramics; Dental Materials; Dental Porcelain; Flexural Strength; Humans; Materials Testing; Pliability; Surface Properties
PubMed: 34214922
DOI: 10.1016/j.jmbbm.2021.104658