Evaluation of marginal and internal fit of lithium disilicate CAD-CAM crowns with different finish lines by using a micro-CT technique

Objective: Studies demonstrated that as one of the newly developed restorative materials, monolithic zirconia resolved several issues of zirconia restoration. Therefore, marginal accuracy and internal fit are necessary for clinical success and quality of restorations, and cement space may influence the marginal fit. Thus, the present research aimed to investigate the effects of the cement thickness and kind of restoration on the marginal discrepancy. Material and methods: In this study, 20 maxillary left first molars, prepared by DRSK Co., were used to fabricate a full crown. Two types of material included monolithic zirconia (Zolid) and Sintron were used to make a full crown. Samples from each group were scanned by dental laboratory 3D scanner and designed and processed using CAD-CAM. The samples were divided into four groups of five with 30- and 50- µm cement spaces. In order to assess the vertical marginal discrepancy, the crowns were fitted on their respective teeth without using any mediator and examined by a micro-CT scanner. Data were analyzed by SPSS software. Results: It has been found that marginal discrepancy in Sintron is higher than the discrepancy of monolithic zirconia. In fact, monolithic zirconia with 50-micron cement space exhibited the least marginal discrepancy and the cement space in Sintron did not significantly influence the marginal discrepancy. Conclusion: It has been concluded that the material kinds and cement space influence the restoration marginal discrepancy constructed by digital workflow. KEYWORDSDental cements; Dental marginal adaptation; X-Raymicrotomography.

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Marginal and Internal Fit of Conventional Metal-Ceramic and Lithium Disilicate CAD/CAM Crowns

The International Journal of Prosthodontics ◽

10.11607/ijp.4089 ◽

2015 ◽

Vol 28 (5) ◽

pp. 519-521 ◽

Cited By ~ 5

Author(s):

Se-Jin Nam ◽

Mi-Jung Yoon ◽

Won-Hee Kim ◽

Gil-Ju Ryu ◽

Min-Ki Bang ◽

...

Keyword(s):

Lithium Disilicate ◽

Metal Ceramic ◽

Cad Cam ◽

Internal Fit

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Micro-CT Evaluation of the Marginal and Internal Fit of Crown and Inlay Restorations Fabricated Via Different Digital Scanners belonging to the Same CAD-CAM System

The International Journal of Prosthodontics ◽

10.11607/ijp.6822 ◽

2021 ◽

Author(s):

Zeynep Ekici ◽

Mehmet Kılıçarslan ◽

Burak Bilecenoğlu ◽

Mert Ocak

Keyword(s):

Micro Ct ◽

Cad Cam ◽

Ct Evaluation ◽

Internal Fit

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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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Micro-CT Analysis of Y-TZP Copings Made by Different CAD/CAM Systems: Marginal and Internal Fit

International Journal of Dentistry ◽

10.1155/2018/5189767 ◽

2018 ◽

Vol 2018 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Rafaella Caramori Saab ◽

Leonardo Fernandes da Cunha ◽

Carla Castiglia Gonzaga ◽

Amanda Mahammad Mushashe ◽

Gisele Maria Correr

Keyword(s):

Tetragonal Zirconia ◽

Micro Ct ◽

Ceramic System ◽

Cad Cam ◽

Ceramic Blocks ◽

Ct Analysis ◽

Ct Technology ◽

Internal Adaptation ◽

Internal Fit ◽

Ceramic Crown

Purpose. The aim of the study was to measure the marginal and internal adaptation (MIA) of zirconia copings, made of 4 ceramic systems for CAD/CAM, using microcomputed tomography (micro-CT) technology. Material and Methods. Two identical stainless steel models were used, representing a preparation for full ceramic crown on a lower molar. The master models were then scanned for the production of copings from specific yttrium oxide partially stabilized tetragonal zirconia polycrystal ceramic blocks of each system (n=10): Cerec/inCoris Zi, Sirona; Cercon/Cercon base, Dentsply; Ceramill/Ceramill Zi, Amann Girrbach; and Lava/Lava Frame Zirconia, 3M ESPE. MIA was evaluated measuring 4 points as follows: marginal gap (MG), axial wall gap (AW), axio-occlusal angle gap (AO), and central occlusal area gap (CO). The data were statistically analyzed by ANOVA and Tukey’s test (α = 0.05). Results. The ceramic system Lava showed greater internal desadaptation (80.75 ± 22.69 µm) while CEREC presented the lowest values (49.92 ± 11.77 µm). There were significant differences between the measurement points evaluated. CO demonstrated the greater values (77.03 ± 22.61 µm). All marginal and internal adaptation values were considered clinically acceptable. Conclusion. It was concluded that there was an influence of the type of ceramic system in marginal and internal adaptation of copings in zirconia.

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