Marginal Fitness in Vertical and Horizontal Crown Preparations: A Comparative Analysis
DOI:
https://doi.org/10.32828/mdj.v22i1.1205Keywords:
Marginal adaptation, vertical preparation, shoulder preparation, lithium disilicate, zirconia, crownAbstract
Objectives: This study focused on comparing the marginal fit of crowns made of zirconia and lithium disilicate, using two types of preparation designs (vertical feather edge, horizontal shoulder) for both cemented and non-cemented situations. Methods: Forty maxillary premolars (all extracted) were randomly assigned to one of two groups based on material type: Lithium Disilicate (Group A) and Monolithic Zirconia (Group B). Within each of these groups, the teeth were further divided into two subgroups based on margin design: Feather Edge and Shoulder Preparation Designs (n=10). All specimens had standardized preparations performed with the aid of a modified dental surveyor, followed by digital scans. For the Crown (s) & Processes created by ExoCad and constructed via Pressing Technique (Lithium Disilicate) and Milling Technique (Zirconia), the preparation margins were evaluated pre -& Post Cementation via digital microscopy at 40x magnification at each Specimens Marked 16 Standardized locations using ImageJ Software. All standardized evaluations were subjected to: Two-Way ANOVA, Tukey HSD, AND Paired 't-test' statistical analyses. Results: After cementation all groups exhibited more of a marginal gap. The groups with vertical preparations A1 and B1 had a significantly less marginal gap compared to groups with horizontal preparations A2 and B2 prior to and following cementation. Group A1 had the least amount of gap and therefore exhibited a more favorable marginal adaptation of the lithium disilicate when using a vertical preparation than did groups A2, B1, and B2. There were significant differences between groups according to statistical analysis (p < 0.05). Conclusion: The marginal adaptation of vertically prepared edges (feather edge/preparation) compared to horizontally prepared (shoulder) edges produced significant differences; this was regardless of which type or class of ceramic material used. The findings indicate that by using minimally invasive vertical preparation techniques; the longevity of restorations and their fit can be greatly enhanced
References
Abdulazeez, M. I. and M. A. Majeed (2021). "Fracture strength of monolithic zirconia crowns with modified vertical preparation: a comparative in vitro study." European Journal of Dentistry 16(01): 209-214.
Abdulla, H. A. and M. A. Majeed (2020). "Assessment of bioactive resin-modified glass ionomer restorative as a new CAD/CAM material. Part I: Marginal fitness study." Indian J Forensic Med Toxicol 14(1): 865-870.
Abdullah, L. S. and A. F. Ibraheem (2017). "The effect of finishing line designs and occlusal surface reduction schemes on vertical marginal fit of full contour CAD/CAM zirconia crown restorations (a comparative in vitro study)." Int J Dent Oral Health 4(1): 1-6.
Adabo, G. L., D. Longhini, M. R. Baldochi, E. T. P. Bergamo and E. A. Bonfante (2023). "Reliability and lifetime of lithium disilicate, 3Y-TZP, and 5Y-TZP zirconia crowns with different occlusal thicknesses." Clinical Oral Investigations 27(7): 3827-3838.
Akrawatcharawittaya, P., T. Sriamporn, S. Vuddhakanok, N. Thamrongananskul and A. Klaisiri (2024). "The Effect of a Dual Cure Activator on Self-Adhesive Resin Cements and Zirconia Shear Bond Strength." Ceramics 7(3): 1237-1246.
Al-Dulaijan, Y. A., H. M. Aljubran, N. M. Alrayes, H. A. Aldulaijan, M. AlSharief, F. E. Aljofi and M. S. Ibrahim (2023). "Clinical outcomes of single full-coverage lithium disilicate restorations: A systematic review." The Saudi dental journal 35(5): 403-422.
Al-Haj Husain, N., M. Özcan, N. Dydyk and T. Joda (2022). "Conventional, speed sintering and high-speed sintering of zirconia: A systematic review of the current status of applications in dentistry with a focus on precision, mechanical and optical parameters." Journal of clinical medicine 11(16): 4892.
Al-khafaji, S. and H. Jasim (2020). "Fracture Resistance of Endodontically Treated Teeth Restored by Full Crown and Two Endocrowns Preparation Design Made from Lithium Disilicate Material (A Comparative in Vitro Study)." Int. Med. J 25: 2531-2542.
Alex, G. (2019). "Zirconia-separating fact from fiction." Oral Health 9(7): 60-61.
Ashour, A. M., M. M. El-Kateb and A. S. Azer (2024). "The effect of two preparation designs on the fracture resistance and marginal adaptation of two types of ceramic crowns using CAD/CAM technology (In vitro study)." BMC Oral Health 24(1): 1065.
Bonfanti‐Gris, M., G. Pradies, B. Moron‐Conejo, A. Gil and F. Martinez‐Rus (2024). "Vertical Versus Horizontal Finishing Lines for Dental Preparations: A Systematic Review With Meta‐Analysis." Journal of Esthetic and Restorative Dentistry.
Cetik, S., B. Bahrami, I. Fossoyeux and R. Atash (2017). "Adaptation of zirconia crowns created by conventional versus optical impression: in vitro study." The Journal of Advanced Prosthodontics 9(3): 208-216.
Comlekoglu, M., M. Dundar, M. Özcan, M. Gungor, B. Gokce and C. Artunc (2009). "Influence of cervical finish line type on the marginal adaptation of zirconia ceramic crowns." Operative dentistry 34(5): 586-592.
Cortellini, D. and A. Canale (2012). "Bonding lithium disilicate ceramic to feather-edge tooth preparations: a minimally invasive treatment concept." Journal of Adhesive Dentistry 14(1): 7.
Dauti, R., B. Cvikl, A. Franz, U. Y. Schwarze, B. Lilaj, T. Rybaczek and A. Moritz (2016). "Comparison of marginal fit of cemented zirconia copings manufactured after digital impression with lava™ COS and conventional impression technique." BMC Oral Health 16: 1-8.
Di Febo, G., A. Bedendo, F. Romano, F. Cairo and G. Carnevale (2015). "Fixed prosthodontic treatment outcomes in the long-term management of patients with periodontal disease: a 20-year follow-up report." Int J Prosthodont 28(3): 246-251.
El-Dessouky, R. A., M. M. Salama, M. A. Shakal and A. M. Korsel (2015). "Marginal adaptation of CAD/CAM zirconia-based crown during fabrication steps." Tanta Dental Journal 12(2): 81-88.
El-Helali, R., A. H. Dowling, E. L. McGinley, H. F. Duncan and G. J. P. Fleming (2013). "Influence of resin-based composite restoration technique and endodontic access on cuspal deflection and cervical microleakage scores." Journal of dentistry 41(3): 216-222.
El Eneen, M. A., G. El-Naggar and M. Taymour (2019). "Marginal accuracy of zirconium reinforced lithium silicate (Vita Suprinity) crowns with two marginal designs before and after cementation under thermo mechanical cycling." Int J Appl Decis Sci 5: 382e390.
Elalfy, N. S. M., R. A. A. Shetawey and R. M. Alassar (2024). "Effect of Vertical versus Horizontal Preparation on Marginal Accuracy and Fracture Resistance of Monolithic Zirconia Crowns." Al-Azhar Journal of Dentistry 11(2): 13.
Elsherbini, M., W. Al-Zordk, M. Diaa, R. A. Amin and A. A. Sakrana (2022). Effect of vertical preparation on fit of heat pressed zirconia reinforced lithium disilicate and monolithic zirconia three-unit fixed partial dentures: A comparative study, Research Square Platform LLC.
Fahmy, N., H. Katamish, R. Elbasty and M. Abbas (2022). "Vertical marginal gap assessment of CAD ON veneered PEKK crowns versus CAD ON veneered zirconia crowns (a randomized in vitro study)." Egyptian Dental Journal 68(4): 3443-3454.
Faul, F., E. Erdfelder, A. Buchner and A.-G. Lang (2009). "Statistical power analyses using G* Power 3.1: Tests for correlation and regression analyses." Behavior research methods 41(4): 1149-1160.
Findakly, M. B. and H. H. Jasim (2019). "Influence of preparation design on fracture resistance of different monolithic zirconia crowns: A comparative study." J Adv Prosthodont 11(6): 324-330.
Fráter, M., T. Sáry, J. Molnár, G. Braunitzer, L. Lassila, P. K. Vallittu and S. Garoushi (2022). "Fatigue performance of endodontically treated premolars restored with direct and indirect cuspal coverage restorations utilizing fiber-reinforced cores." Clinical oral investigations 26(4): 3501-3513.
Fuzzi, M., M. G. TriCariCo, E. F. Cagidiaco, G. Bonadeo, R. Sorrentino and M. Ferrari (2017). "Nanoleakage and internal adaptation of zirconia and lithium disilicate single crowns with feather edge preparation." Journal of Osseointegration 9(2): 250-262.
Gonzalo, E., M. J. Suárez, B. Serrano and J. F. Lozano (2009). "A comparison of the marginal vertical discrepancies of zirconium and metal ceramic posterior fixed dental prostheses before and after cementation." J Prosthet Dent 102(6): 378-384.
Gunel, A., M. B. Guncu, S. M. Uzel, G. Aktas, H. Arikan, N. Reiss and I. Turkyilmaz (2023). "Analysis of the impact of various finish line designs and occlusal morphologies on the accuracy of digital impressions." J Dent Sci 18(3): 1264-1271.
Hasanzade, M., M. Aminikhah, K. I. Afrashtehfar and M. Alikhasi (2021). "Marginal and internal adaptation of single crowns and fixed dental prostheses by using digital and conventional workflows: A systematic review and meta-analysis." The Journal of prosthetic dentistry 126(3): 360-368.
Holmes, J. R., S. C. Bayne, G. A. Holland and W. D. Sulik (1989). "Considerations in measurement of marginal fit." The Journal of prosthetic dentistry 62(4): 405-408.
Ibraheem, A. F. and S. J. A. Hmedat (2013). "An in vitro evaluation of fit of the crowns fabricated by zirconium oxide-based ceramic CAD/CAM systems, before and after porcelain firing cycles and after glaze cycles." J Baghdad Coll Dent 25(1): 43-48.
Kasem, A. T., A. A. Sakrana, M. Ellayeh and M. Özcan (2020). "Evaluation of zirconia and zirconia‐reinforced glass ceramic systems fabricated for minimal invasive preparations using a novel standardization method." Journal of Esthetic and Restorative Dentistry 32(6): 560-568.
Khaliq, A. and I. al-rawi (2014). "Fracture Strength of Laminate Veneers Using Different Restorative Materials and Techniques : A Comparative in Vitro Study." Journal of Baghdad College of Dentistry 26: 1-8.
Kocaağaoğlu, H., H. I. Kılınç and H. Albayrak (2017). "Effect of digital impressions and production protocols on the adaptation of zirconia copings." The Journal of prosthetic dentistry 117(1): 102-108.
Kongkiatkamon, S., D. Rokaya, S. Kengtanyakich and C. Peampring (2023). "Current classification of zirconia in dentistry: an updated review." PeerJ 11: e15669.
Mahdi, A. S. and M. A. Majeed (2019). "Marginal Fitness of Monolithic Zirconia Crowns Fabricated from Direct Digital Scanning, Impression Scanning & Indirect Digital Scanning Using Different Impression Materials." Indian Journal of Public Health Research & Development 10(11).
Mansi, Z. M., A. M. Al-Shamma and A. R. Saleh (2024). "Assessment of marginal adaptation of indirect zirconia crown restorations using self-adhesive resin cements modified with polylysine antibacterial particles." Journal of Baghdad College of Dentistry 36(4): 50-60.
Mugri, M. H., H. Dewan, M. E. Sayed, F. I. Shaabi, H. I. Hakami, H. F. Jokhadar, N. M. Alqahtani, A. A. Alshahrani, A. S. Alabdullah and A. H. Alshehri (2023). "The effect of a digital manufacturing technique, preparation taper, and finish line design on the marginal fit of temporary molar crowns: An in-vitro study." Biomedicines 11(2): 570.
Nasir, M. Q. (2023). "Marginal adaptation of different monolithic zirconia crowns with horizontal and vertical finish lines: A comparative in vitro study." Journal of Dental Research, Dental Clinics, Dental Prospects 17(4): 235.
Noè, G., A. Toffoli, E. Foce, G. Di Febo, G. Carnevale, R. Bonfiglioli, G. M. Macaluso and E. Manfredi (2023). "Vertical Edgeless Preparation: Periodontal Dominance in Prosthetic Crown Preparation." Prosthesis 5(2): 358-367.
Özkurt-Kayahan, Z. (2016). "Monolithic zirconia: A review of the literature." Biomed Res 27(4): 1427-1436.
Patroni, S., G. Chiodera, C. Caliceti and P. Ferrari (2010). "CAD/CAM technology and zirconium oxide with feather-edge marginal preparation." Eur J Esthet Dent 5(1): 78-100.
Sanches, I. B., T. C. Metzker, R. Kappler, M. V. Oliveira, A. O. Carvalho and E. M. C. X. Lima (2023). "Marginal adaptation of CAD-CAM and heat-pressed lithium disilicate crowns: A systematic review and meta-analysis." The Journal of Prosthetic Dentistry 129(1): 34-39.
Schmitz, J. H., D. Cortellini, S. Granata and M. Valenti (2017). "Monolithic lithium disilicate complete single crowns with feather-edge preparation design in the posterior region: A multicentric retrospective study up to 12 years." Quintessence International (Berlin, Germany: 1985): 601-608.
Shillingburg, H. T., S. Hobo, L. D. Whitsett, R. Jacobi and S. E. Brackett (1997). Fundamentals of fixed prosthodontics, Quintessence Publishing Company Chicago, IL, USA.
Sumanth, K. S., S. Poovani and N. K. Sonnahalli (2020). "Evaluation of Effect of Fabrication Steps on Marginal Adaptation of CAD/CAM Zirconia-based Crowns in Comparison to Sintered PFM Crowns: An In Vitro Study." International Journal of Prosthodontics and Restorative Dentistry 10(4): 151-157.
Wahsh, M. and D. Taha (2020). "IN VITRO EVALUATION OF THE MARGINAL INTEGRITY OF MONOLITHIC CERAMIC CROWNS UTILIZING DIFFERENT MACHINABLE BLOCKS FABRICATED FOR MINIMALLY INVASIVE VERTICAL PREPARATION DESIGNS." Egyptian Dental Journal 66(4): 2597-2606.
Wolfart, S., S. M. Wegner, A. Al-Halabi and M. Kern (2003). "Clinical evaluation of marginal fit of a new experimental all-ceramic system before and after cementation." Int J Prosthodont 16(6): 587-592.
Zarone, F., M. I. Di Mauro, P. Ausiello, G. Ruggiero and R. Sorrentino (2019). "Current status on lithium disilicate and zirconia: a narrative review." BMC Oral Health 19(1).
Zheng, B.-w., S. Cao, M. A. A. Al-Somairi, J. He and Y. Liu (2022). "Effect of enamel-surface modifications on shear bond strength using different adhesive materials." BMC Oral Health 22(1): 224.
Zhou, Y., W. Chen, H. Zhu, X. Liu, H. Yang and F. He (2025). "Effect of machining method and margin design on the accuracy and margin quality of monolithic zirconia crowns." J Prosthet Dent 133(2): 592.e591-592.e599.
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