Fit of lithium disilicate crowns fabricated from conventional and digital impressions assessed with micro-CT

The replacement of classical fillings, especially in the posterior area with different types of inlays has become a common solution used in order to improve all parameters which insure a long lasting treatment. Vrious ceramic materials and systems are available, but so far an ideal ceramic material suited for all clinical situations, has not been found. The range of ceramic materials as: lithium disilicate, aluminum oxide, zirconium oxide and hybrid ceramics enhance the possibilities of using ceramic inalys in various clinical situations. Marginal adaptation is one of the most important conditions for long-term success for any type of material. The marginal discrepancy of fixed restorations is one of the main factors which lead to failure of the prosthetic treatment.The purpose of the present study is to compare a 2D and 3D method for evaluating the marginal fit for pressed lithium dislicate inlays (Emax). The two used methods were: SEM- electronic microscopy and micro CT.

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Assessment of the Internal Fit of Lithium Disilicate Crowns Using Micro-CT

Journal of Prosthodontics ◽

10.1111/jopr.12274 ◽

2015 ◽

Vol 24 (5) ◽

pp. 381-386 ◽

Cited By ~ 33

Author(s):

David P. Alfaro ◽

N. Dorin Ruse ◽

Ricardo M. Carvalho ◽

Chris C. Wyatt

Keyword(s):

Lithium Disilicate ◽

Micro Ct ◽

Internal Fit

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Three-dimensional Marginal Evaluation of Two Pressed Materials Using Micro-CT Technology

Revista de Chimie ◽

10.37358/rc.17.3.5514 ◽

2017 ◽

Vol 68 (3) ◽

pp. 615-618

Author(s):

Sorana Baciu ◽

Cristian Berece ◽

Adrian Florea ◽

Alexandru Victor Burde ◽

Anda Munteanu ◽

...

Keyword(s):

Statistical Difference ◽

Three Dimensional ◽

Lithium Disilicate ◽

Marginal Adaptation ◽

Micro Ct ◽

Thermoplastic Resin ◽

Marginal Gap ◽

Marginal Fit ◽

Significant Statistical Difference ◽

Ct Technology

The main goal of the present study is to compare the marginal fit of two different kind of pressed materials: a partially crystalline thermoplastic resin reinforced with ceramic particles (BioHPP) and lithium disilicate (EMax), through the use of the microCT technique. After extraction of four caries-free mandibular first molars, first class inlay cavities were prepared. For each tooth two inlays were manufactured- one by using BioHPP thermoplastic resin (n=4) and one by using Emax Press lithium disilicate (n=4). The marginal gap was analyzed circumferentially at the occlusal margin using a Bruker micro CT, by measuring the distance at the occlusal limit of the cavities, between the restoration and the tooth in several points for every surface of each tooth before cementing. Data were analyzed statistically using the Mann-Whitney U test and the Pearson�s correlation coefficient (a=0.05). A significant statistical difference was found between the marginal gap size obtained for BioHPP and Emax inlays (p[0.001). For the Emax inlays the marginal gap had an average of 72mm, while for BioHPP the average was 94 �m. Both types of used materials offer a good marginal adaptation. By summing up the gathered data we can conclude that the pressed ceramics shows a better marginal fit than the pressed resin, probably because of the different processing methods: sintering versus polymerizing with different shrinkage values.

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In vitro Evaluation of the Marginal Fit and Internal Adaptation of Zirconia and Lithium Disilicate Single Crowns: Micro-CT Comparison Between Different Manufacturing Procedures

The Open Dentistry Journal ◽

10.2174/1874210601812010160 ◽

2018 ◽

Vol 12 (1) ◽

pp. 160-172 ◽

Cited By ~ 11

Author(s):

Francesco Riccitiello ◽

Massimo Amato ◽

Renato Leone ◽

Gianrico Spagnuolo ◽

Roberto Sorrentino

Keyword(s):

Clinical Success ◽

Lithium Disilicate ◽

Resin Cement ◽

Micro Ct ◽

Marginal Fit ◽

Restorative Materials ◽

Cad Cam ◽

Internal Adaptation ◽

Single Crowns

Background:Prosthetic precision can be affected by several variables, such as restorative materials, manufacturing procedures, framework design, cementation techniques and aging. Marginal adaptation is critical for long-term longevity and clinical success of dental restorations. Marginal misfit may lead to cement exposure to oral fluids, resulting in microleakage and cement dissolution. As a consequence, marginal discrepancies enhance percolation of bacteria, food and oral debris, potentially causing secondary caries, endodontic inflammation and periodontal disease.Objective:The aim of the presentin vitrostudy was to evaluate the marginal and internal adaptation of zirconia and lithium disilicate single crowns, produced with different manufacturing procedures.Methods:Forty-five intact human maxillary premolars were prepared for single crowns by means of standardized preparations. All-ceramic crowns were fabricated with either CAD-CAM or heat-pressing procedures (CAD-CAM zirconia, CAD-CAM lithium disilicate, heat-pressed lithium disilicate) and cemented onto the teeth with a universal resin cement. Non-destructive micro-CT scanning was used to achieve the marginal and internal gaps in the coronal and sagittal planes; then, precision of fit measurements were calculated in a dedicated software and the results were statistically analyzed.Results:The heat-pressed lithium disilicate crowns were significantly less accurate at the prosthetic margins (p<0.05) while they performed better at the occlusal surface (p<0.05). No significant differences were noticed between CAD-CAM zirconia and lithium disilicate crowns (p>0.05); nevertheless CAD-CAM zirconia copings presented the best marginal fit among the experimental groups. As to the thickness of the cement layer, reduced amounts of luting agent were noticed at the finishing line, whereas a thicker layer was reported at the occlusal level.Conclusion:Within the limitations of the presentin vitroinvestigation, the following conclusions can be drawn: the recorded marginal gaps were within the clinical acceptability irrespective of both the restorative material and the manufacturing procedures; the CAD-CAM processing techniques for both zirconia and lithium disilicate produced more consistent marginal gaps than the heat-pressing procedures; the tested universal resin cement can be safely used with both restorative materials.

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Effect of different impression methods and ceramic materials on adaptation of inlays

Brazilian Dental Science ◽

10.14295/bds.2018.v21i3.1543 ◽

2018 ◽

Vol 21 (3) ◽

pp. 296

Author(s):

Marília Pivetta Rippe ◽

Elen Guerra ◽

Arianne Vallim Pinto Coelho ◽

Lilian Costa Anami ◽

Renata Marques de Melo Marinho ◽

...

Keyword(s):

Lithium Disilicate ◽

Ceramic Materials ◽

Digital Impression ◽

Marginal Adaptation ◽

Digital Impressions ◽

Cad Cam ◽

Ceramic Blocks ◽

Dental Impression ◽

Internal Adaptation ◽

Ceramic Inlay

Objective: The aim of this study was to evaluate the internal and marginal adaptation of inlays fabricated from different types of impressions (conventional and digital) and different ceramics (feldspathic and lithium disilicate). Material and Methods: Forty premolars were prepared for all-ceramic inlay restoration and assigned to 4 groups (n=10), according to the impression method (conventional with addition silicone and digital impressions) and ceramic type (lithium disilicate and feldspathic ceramic blocks). For each type of impression, 10 inlays were fabricated from lithium disilicate blocks and the other 10 from feldspathic ceramic blocks, by means of the CAD-CAM system. The internal adaptation was analyzed by replica. The marginal fit was analyzed under a stereomicroscope by directly measuring the gap formed between the inlay and the tooth in the proximal and occlusal regions. Results: The marginal or internal adaptations were not affected by type of impression (conventional = digital impression), irrespective of the ceramic type. Only the internal adaptation was affected by material, i.e., feldspathic ceramic had lower values than disilicate ceramic, when considering the digital impression. Conclusion: The conventional and digital impressions promote similar marginal and internal adaptation of tested feldspathic and disilicate ceramic inlays. For digital impression the feldspathic ceramic showed better internal adaptation than lithium disilicate. KeywordsCeramics; Dental internal adaptation; Dental marginal adaptation; Dental impression technique.

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Marginal Fit Evaluation Trough Micro-CT Technology of Pressed vs Milled Ceramic Inlays

Revista de Chimie ◽

10.37358/rc.17.8.5791 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1919-1922

Author(s):

Marius Manole ◽

Cristian Berece ◽

Adrian Florea ◽

Alexandru Victor Burde ◽

Cosmin Sinescu ◽

...

Keyword(s):

Glass Ceramic ◽

Statistical Significance ◽

Lithium Disilicate ◽

Micro Ct ◽

Marginal Gap ◽

Marginal Fit ◽

Ceramic Inlays ◽

Multiple Comparison Test ◽

Ct Technology ◽

One Way Anova

The goal of the present study is to compare the marginal fit using microCT of ceramic inlays obtained using two different technologies: pressing technique (lithium disilicate) and milling technique (milled leucite glass-ceramic). After extraction of four caries-free mandibular first molars, first class inlay cavities were prepared. For each tooth two inlays were manufactured- one by using pressed lithium disilicate (Emax) (n=4) and one by using milled leucite glass-ceramic (n=4). The marginal gap was analyzed circumferentially at the occlusal margin using a table-top Bruker micro CT, by measuring the distance at the occlusal limit of the cavities, between the restoration and the tooth in several points for every surface of each tooth before cementing. Data were analyzed statistically using One �way ANOVA with Tukey�s Multiple Comparison Test performed using 5.00 for Windows (GraphPad Prism 5.00 Software, San Diego, California USA). When the marginal gaps of the inlays made out of different materials on the same tooth were compared, only one result had no statistical significance. The program expressed also results by comparing the gaps of pressed vs milled restorations on different teeth. 11 out of 16 results had statistical significance. Although statistical significance between the two studied materials, we can conclude that both used materials offer a good marginal adaptation within the acceptable limits. By summing up the gathered data we can conclude that the milled ceramic shows a better marginal fit than the pressed ceramic.

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