A Comparative Study of the Marginal Fit of Endocrowns Fabricated From Three Different Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) Ceramic Materials: An In Vitro Study

Abstract

Introduction: The marginal seal and adaptation are important factors for successful restoration. An inadequate marginal seal can lead to bacterial microleakage, plaque accumulation, and eventually treatment failure This in vitro study aimed to compare the marginal gap of endocrowns fabricated from three different computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic materials. Methods: Thirty extracted mandibular molars were selected for the study. Endocrown preparations were completed after root canal treatment. Teeth were divided into three groups to receive endocrowns fabricated of lithium disilicate ceramic (IPS-e.max CAD, Ivoclar Vivadent AG, Schaan, Liechtenstein), zirconia-reinforced lithium silicate ceramic (VITA Suprinity®, VITA Zahnfabrik, Bad Säckingen, Germany), and polymer-infiltrated ceramic (VITA Enamic®, VITA Zahnfabrik). The digital impressions were transferred to the design software to construct the endocrowns. The endocrowns were milled and cemented. The marginal fit was examined using a digital camera stereomicroscope at a magnification of 80X. Images were transferred to Image-J software (National Institutes of Health, Bethesda, Maryland, United States) to measure the marginal gap. Results: One-way ANOVA showed a significant difference in the marginal gap between the different ceramic groups (P=0.006). Tukey’s Honest Significant Difference (HSD) post-hoc test showed that VITA Suprinity had significantly higher gap width values than VITA Enamic (P=0.005). No significant differences in gap width values were found between VITA Enamic and IPS e.max CAD or between VITA Suprinity and IPS e.max CAD (P>0.05). Conclusion: The marginal gap of endocrown restorations varies with different CAD/CAM materials (zirconia-reinforced lithium silicate glass-ceramic, polymer-infiltrated hybrid ceramic, and lithium disilicate glass-ceramic), but are all within clinically acceptable marginal gap width.

A Comparative Analysis of Marginal Adaptation Values between Lithium Disilicate Glass Ceramics and Zirconia-Reinforced Lithium Silicate Endocrowns: A Systematic Review of In Vitro Studies

“…The highest number of publications, 7 studies (41%), was from the year 2023 [ 12 – 15 , 19 , 20 , 22 ], followed by years between 2020 and 2022, with 6 studies (35%) [ 20 , 21 , 25 – 28 ]. Fourteen (76%) studies reported using natural teeth [ 12 – 15 , 17 – 23 , 25 – 27 ], 12 studies (71%) were for mandibular arches [ 13 – 17 , 19 – 20 , 22 – 25 , 27 ], and 11 studies (65%) were for molars [ 13 – 16 , 19 , 22 – 25 , 27 , 28 ]. LDGC and zirconia were the most common all-ceramic materials used for endocrown constructions, with 35% and 30%, respectively, and either alone or in comparisons with other all-ceramic materials.…”

“…LDGC and zirconia were the most common all-ceramic materials used for endocrown constructions, with 35% and 30%, respectively, and either alone or in comparisons with other all-ceramic materials. The manual abutment preparation for endocrowns was used in approximately 75% of studies [ 13 – 16 , 18 , 21 – 28 ], scanning was used in 90% of studies of endocrown preparation, while the stereomicroscope system was used in 40% of the total studies to record and assess the marginal adaptation in micrometers [ 12 – 18 ]. The information regarding the involved in vitro studies is presented, along with other characteristics, in Table 1 .…”

“…All studies recorded a standard sample size and marginal integrity and followed the manufacturer’s instructions. Out of the studies, only 1 study had a medium risk of bias [ 28 ], while the remaining scored a risk of bias of only 3, which is interpreted as a high level of bias [ 13 , 17 , 19 , 27 ]. Table 2 shows the quality bias assessment of the in vitro studies included in this systematic review.…”

“…Endocrowns can be fabricated by CAD/CAM or heat-press techniques using various ceramic systems, such as lithium silicates and zirconia-reinforced lithium silicates [ 14 , 48 , 49 ]. A variety of the products are used in dental practice and produce prostheses with better accuracy of marginal variation [ 13 , 19 , 21 ]. The precision of CAD/CAM-fabricated endocrown fitting differs depending on the inspecting procedure, milling type step, post-milling dimensional differences, and configuration of the program used.…”

“…Various ceramic systems are used for endocrown fabrications, such as feldspathic ceramics [ 26 , 27 ], lithium disilicate glass ceramics (LDGC) [ 13 , 15 – 19 , 22 , 23 , 25 ], and different types of zirconia [ 13 , 14 , 21 ], which have high mechanical strength and can be acid-etched. Zirconia and LDGC are considered the best choices owing to their mechanical and aesthetic features, including good anti-abrasion, anti-aging, and anti-corrosion properties, translucency, and biocompatibility with natural teeth.…”