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The Journal of Prosthetic Dentistry Oct 2022Selective laser melting (SLM) additive manufacturing (AM) technologies provide an alternative to conventional casting and milling procedures in fabricating metal-ceramic... (Meta-Analysis)
Meta-Analysis Review
Adhesion of veneering porcelain to cobalt-chromium dental alloys processed with casting, milling, and additive manufacturing methods: A systematic review and meta-analysis.
STATEMENT OF PROBLEM
Selective laser melting (SLM) additive manufacturing (AM) technologies provide an alternative to conventional casting and milling procedures in fabricating metal-ceramic dental prostheses. However, the quality of porcelain bond strength to the SLM AM cobalt-chromium (Co-Cr) metal framework of a dental restoration is unclear.
PURPOSE
The purpose of this systematic review and meta-analysis was to identify in vitro studies that reported the porcelain bond strength to SLM AM Co-Cr dental metal alloys and compare the porcelain bond strength values to cast, milled, and additively manufactured Co-Cr dental alloys.
MATERIAL AND METHODS
An electronic systematic review was performed in different databases: MEDLINE/PubMed, EMBASE, World of Science, Cochrane, and Scopus. A manual search was also conducted. Studies that reported the porcelain bond strength to SLM Co-Cr metal alloys and in the English language were included. Two investigators evaluated the quality assessment of the studies by applying the JBI critical appraisal checklist for quasi-experimental studies (nonrandomized experimental studies). A third investigator was consulted to resolve lack of consensus. Two subgroups were created based on the test used, 3-point bend and shear bond strength tests. The porcelain bond strength of cast, milled, and AM Co-Cr dental alloys were compared. The I2 statistic and its associated P value were used to assess the heterogeneity between studies. The Eger test was used for determining significance of the funnel pots.
RESULTS
A total of 216 studies were collected from the electronic and manual searches. After independently evaluating the titles and abstracts by the reviewers, 26 articles were identified. Three of these were excluded after full-text revision. The porcelain bond strength comparison between the cast and AM alloys for the 3-point bend subgroup revealed a significant result for overall effect (P<.001) favoring the SLM method with considerable heterogeneity (I2=83%, P<.001). Furthermore, the porcelain bond strength comparison between cast and milled alloys for the shear bond strength subgroup revealed a significant test for overall effect (P=.04) favoring milled procedures with a nonsignificant unimportant heterogeneity (I2= 0%, P<.47) and for the 3-point bend subgroup (P<.001) favoring milled specimens with a significant considerable heterogeneity (I2=79%, P<.001).
CONCLUSIONS
The metal manufacturing method had no effect on the porcelain bond strength to Co-Cr dental metal alloys.
Topics: Dental Porcelain; Chromium Alloys; Metal Ceramic Alloys; Dental Bonding; Materials Testing; Surface Properties; Cobalt; Chromium; Dental Alloys
PubMed: 34294418
DOI: 10.1016/j.prosdent.2021.01.001 -
The Journal of Prosthetic Dentistry Aug 2015Dental alloy manufacturers advise against the reuse of previously melted alloy. However, for economic reasons, dental laboratories often reuse the casting surplus (sprue... (Review)
Review
STATEMENT OF PROBLEM
Dental alloy manufacturers advise against the reuse of previously melted alloy. However, for economic reasons, dental laboratories often reuse the casting surplus (sprue and metal remaining in the crucible former). Such reuse remains a controversial topic in dental practice.
PURPOSE
The purpose of this systematic review was to assess the effects of remelting dental alloys by evaluating the following parameters: reasons for recasting and associated processes, feasible number of recastings, treatment of alloys before recasting and its effects on cytotoxicity, color of opaque porcelain, castability of alloys, marginal accuracy, mechanical properties, porcelain-metal interfaces, and corrosion.
MATERIAL AND METHODS
The systematic review included all studies on dental alloy recasting. MEDLINE, Dentistry and Oral Science Source, Science Direct, and ISI Web of Science were searched (up to July 2014). Data were extracted and the quality of studies was assessed.
RESULTS
Thirty-four studies published between 1983 and 2014 were included. The number of recastings ranged from 1 to 10. The percentage of new alloy ranged from 0 to 100 wt%, although the mean value was 50 wt%.
CONCLUSIONS
Evidence for the feasibility of adding 50% new metal at each recasting is limited. The number of recastings should be limited to a maximum of 4. No general test protocol can be deduced from these studies, which limits the comparison and exploitation of data. Furthermore, no consensus protocol exists for the evaluation of recasting. Future studies should work toward establishing a standard protocol.
Topics: Color; Corrosion; Dental Alloys; Dental Casting Technique; Dental Porcelain; Equipment Reuse; Humans; Materials Testing; Mechanical Phenomena; Metal Ceramic Alloys; Surface Properties
PubMed: 25935082
DOI: 10.1016/j.prosdent.2015.02.004 -
Dental Research Journal 2022It is a major concern to select a proper ceramic with acceptable strength and esthetic and minimum antagonist wear. Therefore, different ceramics were introduced to... (Review)
Review
It is a major concern to select a proper ceramic with acceptable strength and esthetic and minimum antagonist wear. Therefore, different ceramics were introduced to obtain these advantages with various surface treatments. The aim of this study is to evaluate and report the wear behavior of polished and glazed feldspathic and zirconia crowns in published articles up to 2020. Five electronic databases which were used in this research were MEDLINE (via PubMed), Web of Science, Cochrane Library, Embase, and Scopus from the starting date of databases to January 2020. The Keywords "zirconia," "feldspathic," "dental ceramic," "enamel," "Y-TZP," "wear," "glazed," and "polished" were used. English articles were selected in this paper. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was used as a reporting template as much as possible. Among the initially 133 articles, 59 duplicated articles were removed, and finally, 52 articles were screened and among them, only 16 articles remained for full-text regaining. The results showed that zirconia had significantly less antagonist wear than feldspathic groups, and polishing had less enamel wear than other types of surface treatment like glazing. Only one study showed that glazed zirconia can have more antagonist wear than feldspathic porcelain. Monolithic zirconia had less enamel wear than conventional zirconia and low-fusing feldspathic porcelain showed lower antagonist wear in comparing with other types of feldspathic porcelains.
PubMed: 36605138
DOI: No ID Found -
Clinical Oral Investigations Oct 2023To compare the failure rates and the prevalence of technical complications between full-coverage tooth-supported monolithic zirconia (MZ) and porcelain-veneered zirconia... (Review)
Review
Clinical outcomes of tooth-supported monolithic zirconia vs. porcelain-veneered zirconia fixed dental prosthesis, with an additional focus on the cement type: a systematic review and meta-analysis.
PURPOSE
To compare the failure rates and the prevalence of technical complications between full-coverage tooth-supported monolithic zirconia (MZ) and porcelain-veneered zirconia (PVZ) fixed dental prosthesis, based on a systematic literature review.
METHODS
An electronic search was performed in three databases, supplemented by hand searching. Several statistical methods were used.
RESULTS
Seventy-four publications reported 6370 restorations (4264 PVZ; 2106 MZ; 8200 abutment teeth; 3549 patients), followed up until 152 months. A total of 216 prostheses failed, and survival was statistically significant different between groups. PVZ had higher occurrence of complications than MZ; the difference was especially greater for either minor or major chipping. The difference in prevalence of either minor or major chipping was statistically significant for PVZ prostheses between cementation with glass ionomer and adhesive resin cement (higher), adhesive resin and resin-modified glass ionomer cement (RMGIC, higher), and between RMGIC (higher) and glass ionomer cement. For MZ the difference was significant only for minor chipping between RMGIC (higher) and adhesive resin cement. Abutment teeth to PVZ prostheses more often lost vitality. Decementation was not observed with RMGIC. Air abrasion did not seem to clinically decrease the decementation risk. The 5-year difference in the occurrence of minor or major chipping between MZ and PVZ prostheses was statistically significant, but nor for catastrophic fracture.
CONCLUSION
Tooth-supported PVZ prostheses present higher failure and complication rates than MZ prosthesis. The difference in complications is striking when it comes to chipping.
CLINICAL RELEVANCE
Awareness of the outcome differences between different types of zirconia prostheses is important for clinical practice.
PubMed: 37626273
DOI: 10.1007/s00784-023-05219-4 -
The Journal of Prosthetic Dentistry May 2024The increasing use of computer-aided design and computer-aided manufacturing (CAD-CAM) systems has led to the development of resin-ceramic materials that meet the... (Review)
Review
STATEMENT OF PROBLEM
The increasing use of computer-aided design and computer-aided manufacturing (CAD-CAM) systems has led to the development of resin-ceramic materials that meet the requirements of minimally invasive dentistry, including the resin nanoceramic (RNC) and polymer-infiltrated ceramic network (PICN). The wear characteristics of these materials are unclear.
PURPOSE
The purpose of this systematic review was to compare the wear resistance of resin-ceramic materials when compared with one another or with lithium disilicate glass-ceramics.
MATERIAL AND METHODS
The PubMed, Scopus, and DOSS search engines were used to identify articles published between 2013 and 2021. Two independent researchers conducted the systematic review by following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and by following a combination of keywords.
RESULTS
Of a total of 310 articles, 26 were selected, including only 1 clinical study. Among these, 15 compared resin-ceramic materials with each other, while 11 compared resin-ceramic materials with lithium disilicate ceramics. Two types of wear were used to compare the materials: attrition and abrasion. The most commonly studied materials were 2 RNCs (Lava Ultimate and Cerasmart), 1 PICN (Vita Enamic), and 1 ceramic (IPS e.max CAD). Among the resin-ceramic materials, the PICN (Vita Enamic) showed less wear than the RNCs. Of the RNCs, Cerasmart had less attrition wear and less wear of the opposing teeth.
CONCLUSIONS
Lithium disilicate glass-ceramics have a higher wear resistance than resin-ceramic materials, but they cause more wear of the opposing teeth.
Topics: Computer-Aided Design; Ceramics; Humans; Dental Porcelain; Dental Restoration Wear; Dental Materials; Resins, Synthetic
PubMed: 35459543
DOI: 10.1016/j.prosdent.2022.01.027 -
The Journal of Prosthetic Dentistry Jan 2024Marginal integrity and internal adaptation are key to the long-term success of porcelain laminate veneers. Evidence for their marginal and internal fit is unclear, and... (Meta-Analysis)
Meta-Analysis
STATEMENT OF PROBLEM
Marginal integrity and internal adaptation are key to the long-term success of porcelain laminate veneers. Evidence for their marginal and internal fit is unclear, and the factors affecting such fit have not been identified.
PURPOSE
The purpose of this systematic review and meta-analysis was to summarize the scientific literature assessing the effects of various parameters on the marginal and internal fit of porcelain laminate veneers.
MATERIAL AND METHODS
An electronic search was conducted to identify all relevant published articles on the fit accuracy of ceramic veneers between January 2000 and June 2021 in the PubMed-MEDLINE, Scopus, Embase, Google Scholar, and Web of Science databases. Information, including the study outcomes, in terms of the mean marginal gap, internal gap, and absolute marginal discrepancies of porcelain laminate veneers, was extracted from the selected studies. The inverse-variance random effects model was used to analyze the pooled results and estimate the overall effect based on the heterogeneity of studies (α=.05).
RESULTS
Twenty-one studies were selected for analysis, 2 clinical and 19 in vitro. The risk of bias was "medium" for most studies (19 of 21), and only 2 studies were classified as "high risk." A mean difference of -4.53 μm (95% CI: -21.46 to 12.41) was found, with no statistically significant difference in marginal gap between the pressed and milled fabrication modes (P=.600). As for the internal gap, significant differences were found (mean difference=-40.56 μm; 95% CI: -76.54 to -4.58), with pressed veneers performing better (P=.030). Butt joint preparation design produced significantly (P=.002) lower marginal gaps than the palatal chamfer (mean difference=-14.02 μm; 95% CI: -23.07 to -4.98).
CONCLUSIONS
No significant differences were found between the pressed and milled porcelain laminate veneers for marginal gap, but for the internal gap, the differences were significantly in favor of the pressed type. The butt joint veneer preparation design was significantly better than the palatal chamfer design in terms of marginal fit.
Topics: Ceramics; Computer-Aided Design; Dental Marginal Adaptation; Dental Porcelain; Dental Veneers
PubMed: 35260253
DOI: 10.1016/j.prosdent.2022.01.009 -
Medicina (Kaunas, Lithuania) Dec 2022: Porcelain-fused-to-metal (PFM) prostheses are considered the gold standard for the replacement of missing teeth, however, these have several drawbacks. Therefore,... (Review)
Review
: Porcelain-fused-to-metal (PFM) prostheses are considered the gold standard for the replacement of missing teeth, however, these have several drawbacks. Therefore, lithium disilicate (LDS) prostheses have been introduced for the construction of fixed crowns and bridges. The aim of this systematic review was to ascertain the long-term survival of LDS fixed prostheses in comparison to other materials. : The focused question was 'In patients who have undergone prosthodontic treatment (participants), what are the overall survival rate of lithium disilicate (LDS) crowns and fixed bridges; and how do they relate to survival rates of non-LDS similar restoration are the survival and com-plication rates (outcomes) of LDS-based fixed prostheses with complete coverage (intervention) higher or lower when compared to non-LDS materials (controls)?'. An electronic search was conducted in PubMED/Medline, EMBASE, Google Scholar, and ClinicalTrials.gov for articles published between January 2006 and August 2022 using appropriate MeSH terms and keywords. The following types of studies were included: (1) All types of prospective clinical studies; (2) Clinical studies focusing on the survival of fixed LDS bridges and crowns; (3) Studies using natural teeth with complete coverage as abutment for fixed LDS bridges and crowns; and (4) Studies in English. The following studies were excluded: (1) Laboratory/in vitro studies and studies on LDS prostheses with no description of outcomes or survival rates; (2) Commentaries; (3) Letters to the editor; (4) Reviews; and (5) Internal data from manufacturers. The data from included studies were extracted and the risk of bias was assessed within the studies using ROBINS-I. : A total of 25 studies were included in this systematic review. The overall 5-year and 10-year survival rates were of 95-100% and 71.4-100%, respectively. Generally, three-unit bridges had a significantly lower survival rate over 5 and 10 years compared to single-unit crowns. Overall, the risk of bias in the included studies was moderate. : The LDS-based complete coverage prostheses have a survival rate ranging between 48.6% and 100%. Furthermore, due to the lack of comparative studies, the long-term function and survival of LDS prostheses compared to other material prosthesis (PFM and ZrO) is debatable.
Topics: Humans; Dental Porcelain; Prospective Studies; Crowns; Metals
PubMed: 36676719
DOI: 10.3390/medicina59010095 -
The Journal of Prosthetic Dentistry Jul 2019Different finish-line designs have been advocated for tooth preparations of ceramic crowns. However, scientific evidence is lacking to help clinicians make a proper... (Meta-Analysis)
Meta-Analysis Review
STATEMENT OF PROBLEM
Different finish-line designs have been advocated for tooth preparations of ceramic crowns. However, scientific evidence is lacking to help clinicians make a proper selection.
PURPOSE
The purpose of this systematic review and meta-analysis was to evaluate the effects of finish-line designs on the marginal and internal adaptations of ceramic crowns.
MATERIAL AND METHODS
This report follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature search was conducted in MEDLINE via the PubMed, Embase, and Web of Science databases with no publication year or language limits. In vitro studies comparing the marginal and internal adaptations of ceramic crowns with rounded shoulder and chamfer finish lines were included in the meta-analysis.
RESULTS
Sixteen studies were included in the qualitative synthesis and meta-analyses. Statistical analyses were conducted using the Review Manager Software. Meta-analyses were performed with random-effects models (α=.05). Ceramic crowns with rounded shoulders exhibited significantly better marginal adaptation than those with chamfers (P<.001; mean difference=-7.8; 95% confidence interval=-11.6 to -4.1). Moreover, ceramic crowns with chamfers exhibited significantly better internal adaptation than those with rounded shoulders (P=.020; mean difference=35.0; 95% confidence interval=6.5 to 63.5).
CONCLUSIONS
The difference in marginal adaptation of ceramic crowns using 2 finish-line designs was small, and the clinical significance was low, whereas the results of internal adaptation favored the chamfer finish line.
Topics: Ceramics; Crowns; Dental Marginal Adaptation; Dental Porcelain; Dental Prosthesis Design; Tooth Preparation, Prosthodontic
PubMed: 30782459
DOI: 10.1016/j.prosdent.2018.10.002 -
Journal of Prosthodontics : Official... Feb 2016To review laboratory studies that investigated fatigue resistance of lithium disilicate (LD) crowns and fixed dental prostheses (FDPs) to elucidate study designs and... (Review)
Review
PURPOSE
To review laboratory studies that investigated fatigue resistance of lithium disilicate (LD) crowns and fixed dental prostheses (FDPs) to elucidate study designs and testing parameters.
METHODS
An electronic search was performed in PubMed, Scopus, and Ovid to identify in vitro studies that investigated fatigue resistance of LD crowns and FDPs. The search included all studies published in English in peer-reviewed journals in the period from 1998 to June 2014. The search followed a specific strategy that included combination of the following keywords: lithium disilicate, e.max, empress, all-ceramic, all ceramic, glass ceramic, fatigue, cyclic loading, dynamic loading, chewing simulator, fracture resistance, thermocycling, laboratory simulation, aging, crown, FDPs, FPDs, fixed partial denture, fixed dental prosthesis, and bridge. Studies were selected if mechanical and thermal loading parameters were clearly identified. Search results with abstracts were transferred into Endnote reference system, and duplicates were deleted. The remaining studies were then reviewed at three levels (title, abstract, full text) to further refine the articles.
RESULTS
The initial search retrieved 1044 eligible studies. After deduplication, 864 records were examined by titles and then abstracts; 826 were excluded, and 38 were assessed by full-text reading. In total, 19 articles met inclusion criteria and were included in this study.
CONCLUSION
The studies reviewed showed a level of heterogeneity, as testing parameters were considered through different setups. The current study demonstrated that various setting of the testing parameters and having a lack of testing standardization has likely led to inconsistency in the reported results. The obvious heterogeneity in the setting of testing variables-especially the magnitude of load and number of cycles applied-made it impractical to run direct comparisons between the reviewed studies. Therefore, specific international standardization of fatigue testing of dental restorations is urgently needed to ensure the delivery of consistent, indicative, and comparable data.
Topics: Crowns; Dental Porcelain; Dental Restoration Failure; Denture, Partial, Fixed; Humans
PubMed: 26505638
DOI: 10.1111/jopr.12376 -
The Journal of Prosthetic Dentistry Oct 2022Although recent studies have reported the success of implant-supported monolithic restorations, consensus on the use of monolithic ceramic restorations is lacking. (Meta-Analysis)
Meta-Analysis Review
STATEMENT OF PROBLEM
Although recent studies have reported the success of implant-supported monolithic restorations, consensus on the use of monolithic ceramic restorations is lacking.
PURPOSE
The purpose of this systematic review and meta-analysis was to evaluate the survival and biological and technical complication rates of monolithic single crowns and fixed partial dentures (FPDs).
MATERIAL AND METHODS
An electronic search was conducted by 2 independent authors on the PubMed/MEDLINE, Scopus, and Cochrane Library databases. The Newcastle-Ottawa scale and Cochrane risk of bias tool were used to assess the quality and risk of bias of the included studies. Meta-analysis was performed by using the R software program.
RESULTS
The search identified 763 articles, 18 of which met the eligibility criteria. A total of 15 studies evaluated monolithic ceramic single crowns, and 4 studies evaluated FPDs. The studies included 1061 monolithic single crowns (524 lithium disilicate, 461 zirconia, and 76 polymer-infiltrated ceramic network [PICN]) and 104 FPDs (36 lithium disilicate and 68 zirconia). Meta-analysis of single-arm studies indicated the proportion of survival, biological, and technical complication rates of 1% (95% confidence interval [CI]: 0% to 3%), 1% (CI: 0% to 4%), and 2% (CI: 1% to 4%), respectively, for single crowns, independent of ceramic material, and 3% (CI: 0% to 34%), 5% (CI: 1% to 21%), and 5% (CI: 1% to 21%) for FPDs, respectively. Only 5 studies performed a direct comparison between monolithic and veneered ceramic restorations, and no significant difference was observed in terms of survival (risk ratio [RR]: 0.68; CI: 0.25-1.91; P=.96), biological (RR: 0.69; CI: 0.31-1.53; P=.35), and technical complication rates (RR: 0.87; CI: 0.40-1.88; P=.29).
CONCLUSIONS
The use of monolithic ceramic can be considered a favorable treatment for tooth-supported single crowns and FPDs, with high survival and low complication rates. However, further randomized controlled trials are needed to reassess these clinical performances, mainly by comparing them with the performance of veneered restorations.
Topics: Dental Restoration Failure; Dental Prosthesis Design; Zirconium; Dental Porcelain; Ceramics; Crowns; Dental Prosthesis, Implant-Supported
PubMed: 33745685
DOI: 10.1016/j.prosdent.2021.01.020