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Materials Science & Engineering. C,... May 2019Zirconia has emerged as a versatile dental material due to its excellent aesthetic outcomes such as color and opacity, unique mechanical properties that can mimic the... (Review)
Review
BACKGROUND
Zirconia has emerged as a versatile dental material due to its excellent aesthetic outcomes such as color and opacity, unique mechanical properties that can mimic the appearance of natural teeth and decrease peri-implant inflammatory reactions.
OBJECTIVE
The aim of this review was to critically explore the state of art of zirconia surface treatment to enhance the biological and osseointegration behavior of zirconia in implant dentistry.
MATERIALS AND METHODS
An electronic search in PubMed database was carried out until May 2018 using the following combination of key words and MeSH terms without time periods: "zirconia surface treatment" or "zirconia surface modification" or "zirconia coating" and "osseointegration" or "biological properties" or "bioactivity" or "functionally graded properties".
RESULTS
Previous studies have reported the influence of zirconia-based implant surface on the adhesion, proliferation, and differentiation of osteoblast and fibroblasts at the implant to bone interface during the osseointegration process. A large number of physicochemical methods have been used to change the implant surfaces and therefore to improve the early and late bone-to-implant integration, namely: acid etching, gritblasting, laser treatment, UV light, CVD, and PVD. The development of coatings composed of silica, magnesium, graphene, dopamine, and bioactive molecules has been assessed although the development of a functionally graded material for implants has shown encouraging mechanical and biological behavior.
CONCLUSION
Modified zirconia surfaces clearly demonstrate faster osseointegration than that on untreated surfaces. However, there is no consensus regarding the surface treatment and consequent morphological aspects of the surfaces to enhance osseointegration.
Topics: Animals; Dental Implants; Dental Materials; Dental Prosthesis Design; Humans; Osseointegration; Surface Properties; Zirconium
PubMed: 30813009
DOI: 10.1016/j.msec.2019.01.062 -
Clinical Oral Implants Research Oct 2018The aim of the present review was to compare the outcomes, that is, survival and complication rates of zirconia-ceramic and/or monolithic zirconia implant-supported... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
The aim of the present review was to compare the outcomes, that is, survival and complication rates of zirconia-ceramic and/or monolithic zirconia implant-supported fixed dental prostheses (FDPs) with metal-ceramic FDPs.
MATERIALS AND METHODS
An electronic MEDLINE search complemented by manual searching was conducted to identify randomized controlled clinical trials, prospective cohort studies and retrospective case series on implant-supported FDPs with a mean follow-up of at least 3 years. Patients had to have been examined clinically at the follow-up visit. Assessment of the identified studies and data extraction was performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson regression models to obtain summary estimates of 5-year proportions.
RESULTS
The search provided 5,263 titles and 455 abstracts. Full-text analysis was performed for 240 articles resulting in 19 studies on implant FDPs that met the inclusion criteria. The studies reported on 932 metal-ceramic and 175 zirconia-ceramic FDPs. Meta-analysis revealed an estimated 5-year survival rate of 98.7% (95% CI: 96.8%-99.5%) for metal-ceramic implant-supported FDPs, and of 93.0% (95% CI: 90.6%-94.8%) for zirconia-ceramic implant-supported FDPs (p < 0.001). Thirteen studies including 781 metal-ceramic implant-supported FDPs estimated a 5-year rate of ceramic fractures and chippings to be 11.6% compared with a significantly higher (p < 0.001) complication rate for zirconia implant-supported FDPs of 50%, reported in a small study with 13 zirconia implant-supported FDPs. Significantly (p = 0.001) more, that is, 4.1%, of the zirconia-ceramic implant-supported FDPs were lost due to ceramic fractures compared to only 0.2% of the metal-ceramic implant-supported FDPs. Detailed analysis of factors like number of units of the FDPs or location in the jaws was not possible due to heterogeneity of reporting. No studies on monolithic zirconia implant-supported FDPs fulfilled the inclusion criteria of the present review. Furthermore, no conclusive results were found for the aesthetic outcomes of both FDP-types.
CONCLUSION
For implant-supported FDPs, conventionally veneered zirconia should not be considered as material selection of first priority, as pronounced risk for framework fractures and chipping of the zirconia veneering ceramic was observed. Monolithic zirconia may be an interesting alternative, but its clinical medium- to long-term outcomes have not been evaluated yet. Hence, metal ceramics seems to stay the golden standard for implant-supported multiple-unit FDPs.
Topics: Ceramics; Databases, Factual; Dental Implants; Dental Materials; Dental Prosthesis Design; Dental Prosthesis, Implant-Supported; Dental Restoration Failure; Denture, Partial, Fixed; Esthetics, Dental; Humans; Metal Ceramic Alloys; Survival Analysis; Zirconium
PubMed: 30328185
DOI: 10.1111/clr.13277 -
Dental Materials : Official Publication... Mar 2022Bulk-fill resin composites are a special group of restorative materials designed to reduce chair time needed to insert a direct composite restoration. However, other...
OBJECTIVE
Bulk-fill resin composites are a special group of restorative materials designed to reduce chair time needed to insert a direct composite restoration. However, other factors determine the clinical success of a restorative material. Clinically the major reasons for failure of direct restorations are secondary caries and fracture of the restoration or the tooth itself. In the long-term composite resin restorations in posterior teeth may be prone to wear. As bulk-fill materials have their own composition that will determine their mechanical properties, the wear resistance may be affected as well. The aim of this in vitro study was to evaluate the wear of bulk-fill composites in comparison with a conventional hybrid composite. The null hypothesis was that there are no differences between the four bulk-fill materials and one traditional highly filled nanohybrid composite for posterior use when subjected to a two-body wear rate test and hardness measurement.
METHODS
Four bulk-fill composites SDR Smart Dentin Replacement (SDR), X-tra base (XBA), FiltekBulk Fill (FUP), Dual-Curing Bulk Composite (FBFL) and conventional nanohybrid resin composite Grandio (GDO) subjected to a two-body wear test against a stainless steel (SS) antagonist wheel. Scanning Electron Microscopy analysis was performed to detect the surface alterations. Microhardness of all samples was tested (n = 5) with a Vickers diamond indenter (5 indentations in each specimen). One-way ANOVA and Tukey's post hoc test (P < 0.01) were used to analyze differences in wear values. The hardness data were submitted to one-way ANOVA test, followed by the Tukey post hoc test (α = 0.05). T-test was applied to compare wear rate in time interval between one day and one month.
RESULTS
The highest wear rate values were recorded for SDR and the lowest wear rate values were for GDO. Hardness was the highest for GDO and the lowest for FBFL.
SIGNIFICANCE
The bulk-fill composites have a higher wear rate and lower hardness than the conventional nanohybrid composite, making them less suitable for stress-bearing restorations.
Topics: Composite Resins; Dental Materials; Hardness; Materials Testing
PubMed: 34972580
DOI: 10.1016/j.dental.2021.12.138 -
Dental Materials Journal Oct 2022One technique for placing of resin-based composite for large posterior cavities is the use of short fiber-reinforced resin-based composite (SFRC) to replace dentin in a... (Review)
Review
One technique for placing of resin-based composite for large posterior cavities is the use of short fiber-reinforced resin-based composite (SFRC) to replace dentin in a biomimetic approach. As endurance under mastication cycles is a significant consideration in the clinical success of resin-based composite posterior restorations, the use of SFRC as a base material may prevent restorative fracture due to the fibers' effectiveness in stopping cracks. This review article specifies the characteristics of SFRC and describes the major underlying mechanisms of short fiber reinforcement for resin-based composite. Insights are further taken from laboratory studies used to define the short fiber-related properties of resin-based composite and the performance of currently available materials, focusing on aspects that are relevant to the reinforcement of resin-based composite. Finally, future standpoints on the development of SFRCs with nano fibers and different resin monomers, and their role in digital dentistry, are discussed.
Topics: Composite Resins; Dental Materials; Dental Restoration, Permanent; Materials Testing
PubMed: 35858793
DOI: 10.4012/dmj.2022-080 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Jun 2020Bulk-fill composite resin are simple to operate, and they reduce polymerization shrinkage and microleakage compare to traditional resin-based composites. However, their... (Review)
Review
Bulk-fill composite resin are simple to operate, and they reduce polymerization shrinkage and microleakage compare to traditional resin-based composites. However, their clinical application could be affected by numerous factors, such as the material itself, light curing, placement techniques, storage condition, and preheating. This review aimed to summarize the definitions, classifications, indications, clinical properties, and influencing factors of the clinical application of bulk-fill resin-based composites and discuss the ways to improve their clinical effectiveness.
Topics: Composite Resins; Dental Materials; Materials Testing; Polymerization; Surface Properties
PubMed: 32573127
DOI: 10.7518/hxkq.2020.03.001 -
Clinical Oral Implants Research Oct 2018The aim of the present systematic review was to analyze the survival and complication rates of zirconia-based and metal-ceramic implant-supported single crowns (SCs).
OBJECTIVES
The aim of the present systematic review was to analyze the survival and complication rates of zirconia-based and metal-ceramic implant-supported single crowns (SCs).
MATERIALS AND METHODS
An electronic MEDLINE search complemented by manual searching was conducted to identify randomized controlled clinical trials, prospective cohort and retrospective case series on implant-supported SCs with a mean follow-up time of at least 3 years. Patients had to have been clinically examined at the follow-up visit. Assessment of the identified studies and data extraction was performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5-year proportions.
RESULTS
The search provided 5,263 titles and 455 abstracts, full-text analysis was performed for 240 articles, resulting in 35 included studies on implant-supported crowns. Meta-analysis revealed an estimated 5-year survival rate of 98.3% (95% CI: 96.8-99.1) for metal-ceramic implant supported SCs (n = 4,363) compared to 97.6% (95% CI: 94.3-99.0) for zirconia implant supported SCs (n = 912). About 86.7% (95% CI: 80.7-91.0) of the metal-ceramic SCs (n = 1,300) experienced no biological/technical complications over the entire observation period. The corresponding rate for zirconia SCs (n = 76) was 83.8% (95% CI: 61.6-93.8). The biologic outcomes of the two types of crowns were similar; yet, zirconia SCs exhibited less aesthetic complications than metal-ceramics. The 5-year incidence of chipping of the veneering ceramic was similar between the material groups (2.9% metal-ceramic, 2.8% zirconia-ceramic). Significantly (p = 0.001), more zirconia-ceramic implant SCs failed due to material fractures (2.1% vs. 0.2% metal-ceramic implant SCs). No studies on newer types of monolithic zirconia SCs fulfilled the simple inclusion criteria of 3 years follow-up time and clinical examination of the present systematic review.
CONCLUSION
Zirconia-ceramic implant-supported SCs are a valid treatment alternative to metal-ceramic SCs, with similar incidence of biological complications and less aesthetic problems. The amount of ceramic chipping was similar between the material groups; yet, significantly more zirconia crowns failed due to material fractures.
Topics: Ceramics; Crowns; Databases, Factual; Dental Implants; Dental Materials; Dental Prosthesis Design; Dental Prosthesis, Implant-Supported; Dental Restoration Failure; Esthetics, Dental; Humans; Metal Ceramic Alloys; Survival Analysis; Zirconium
PubMed: 30328190
DOI: 10.1111/clr.13306 -
Medicine Oct 2019Although all-ceramic crowns have excellent biocompatibility and esthetic appearance, chipping may occur. The mechanical properties of monolithic zirconia restorative...
Although all-ceramic crowns have excellent biocompatibility and esthetic appearance, chipping may occur. The mechanical properties of monolithic zirconia restorative material are superior to those of all-ceramic restorative materials, and chipping caused by chewing hard foods could be avoided. This study aimed to evaluate the clinical efficacy of monolithic zirconia crowns for posterior teeth restorations.A total of 46 patients requiring posterior teeth restorations involving 49 teeth were treated with monolithic zirconia crown procedure. The treatment results were evaluated according to the modified California Dental Association criteria immediately after the procedure, and at 2, 24, 48, and 96 weeks after the procedure. The plaque index, gingival index, probing depth, crown marginal integrity, and attrition of the abutment teeth, antagonist teeth, corresponding contralateral teeth, and antagonist of the corresponding contralateral teeth were assessed. The patients were followed for up to 96 weeks.The marginal adaptation results of all 46 patients were evaluated as excellent, resulting in an excellent rate of 100%. Regarding the crown color match, only 3 cases (6.1%) were evaluated as acceptable. Marginal adaptation, anatomic form, crown margin integrity, color match, and gross fracture did not show significant differences compared with the different time points (P = .999). Surface texture at different time did not change significantly (P = .807). During the 96-week follow-up, 1 crack in the antagonist teeth was found in 1 patient. There were no significant differences in wear of the antagonist teeth at different time points (P = .972). The rate of "excellent" evaluation for crown restorations was 93.9% to 100%.The monolithic zirconia crown had no detectable adverse effects on the periodontal tissues, and the antagonist teeth attrition was small. Therefore, it has good potential in the clinical application of posterior teeth restorations in the short term.
Topics: Crowns; Dental Health Surveys; Dental Materials; Dental Prosthesis Design; Dental Restoration Failure; Female; Humans; Male; Zirconium
PubMed: 31577743
DOI: 10.1097/MD.0000000000017385 -
British Dental Journal May 2022With the phasing down of dental amalgam use in response to the Minamata Convention, it is likely that resin-based composite restoratives will be the dental material of... (Review)
Review
With the phasing down of dental amalgam use in response to the Minamata Convention, it is likely that resin-based composite restoratives will be the dental material of choice for the direct restoration of compromised dentition in the UK, at least for the foreseeable future. The current materials have a finite lifespan, with failures predominately due to either secondary caries or fracture. Consequently, there is considerable in vitro research reported each year with the intention of producing improved materials. This review describes the recent research in materials designed to have low polymerisation shrinkage and increased mechanical properties. Also described is research into materials that are either antimicrobial or are designed to release ions into the surrounding oral environment, with the aim of stimulating remineralisation of the surrounding dental tissues. It is hoped that by describing this recent research, clinicians will be able to gain some understanding of the current research that will potentially lead to new products that they can use to improve patient treatment in the future.
Topics: Composite Resins; Dental Amalgam; Dental Caries; Dental Materials; Dental Restoration, Permanent; Humans
PubMed: 35562465
DOI: 10.1038/s41415-022-4240-8 -
Indian Journal of Dental Research :... 2020Laboratory reports show that fiber-reinforced composites have improved fracture resistance over traditional composites. However, limitations in the biomechanics of tests...
BACKGROUND
Laboratory reports show that fiber-reinforced composites have improved fracture resistance over traditional composites. However, limitations in the biomechanics of tests to evaluate the fracture resistance of fiber-reinforced composites need to be considered for accurate clinical applications.
AIM
To assess the fracture resistance of particulate filler composites, glass fiber-reinforced composites, and polyethylene-fiber reinforced composites by analyzing the different fracture types and failure patterns.
MATERIALS AND METHODS
A standardized incisal (Group I) and mesioincisal fractures (Group II) were prepared on human maxillary central incisors. The test samples were further subdivided according to the restorative material used; particulate filler composites (Filtek Z 250), glass fiber-reinforced composites (fibre splint), and polyethylene-reinforced composites (Ribbond). The type of fractures was evaluated under the stereomicroscope and the failure patterns were analyzed using the graphical output from Universal Testing Machine.
STATISTICAL ANALYSIS
The Chi-square test of association was used to test the association between fiber-reinforced composites and fracture resistance of tooth restoration complex.
RESULTS
No statistical association was observed between fiber-reinforced composites to the type of fractures in both incisal (P = 0.29) and mesioincisal restoration (P = 0.27). A significant association was observed between the fiber-reinforced composites to the failure patterns in both the incisal (P = 0.005) and mesioincisal restoration (P = 0.007).
CONCLUSION
The glass and polyethylene fiber-reinforced composites showed improved fracture resistance properties than the traditional particulate filler composites in both incisal and mesioincisal restorations.
Topics: Composite Resins; Dental Materials; Dental Restoration Failure; Dental Restoration, Permanent; Dental Stress Analysis; Glass; Humans; Materials Testing; Stress, Mechanical; Tooth Fractures
PubMed: 32246697
DOI: 10.4103/ijdr.IJDR_465_18 -
Journal of Dentistry Dec 2013Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is... (Review)
Review
OBJECTIVES
Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics.
DATA/SOURCES
The nature of various fatigue modes is elucidated using fracture test data on ceramic layer specimens from the dental and biomechanics literature.
CONCLUSIONS
Failure modes can change over a lifetime, depending on restoration geometry, loading conditions and material properties. Modes that operate in single-cycle loading may be dominated by alternative modes in multi-cycle loading. While post-mortem examination of failed prostheses can determine the sources of certain fractures, the evolution of these fractures en route to failure remains poorly understood. Whereas it is commonly held that loss of load-bearing capacity of dental ceramics in repetitive loading is attributable to chemically assisted 'slow crack growth' in the presence of water, we demonstrate the existence of more deleterious fatigue mechanisms, mechanical rather than chemical in nature. Neglecting to account for mechanical fatigue can lead to gross overestimates in predicted survival rates.
CLINICAL SIGNIFICANCE
Strategies for prolonging the clinical lifetimes of ceramic restorations are proposed based on a crack-containment philosophy.
Topics: Bite Force; Ceramics; Chemical Phenomena; Dental Materials; Dental Restoration Failure; Humans; Materials Testing; Stress, Mechanical
PubMed: 24135295
DOI: 10.1016/j.jdent.2013.10.007