Citation Information :
Thakkar S, Mahajan N. Correlation of the Effect of Escape Vents in Metal-ceramic Crowns on Seating Discrepancy, Cement Thickness and Microleakage: An In Vitro Study. Int J Prosthodont Restor Dent 2023; 13 (1):39-44.
Purpose: This in vitro study correlated the effect of venting in porcelain fused to metal (PFM) crowns on seating discrepancy, cement thickness, and microleakage.
Materials and methods: Thirty freshly extracted non-carious molars were disinfected with chloramine T and prepared for PFM crowns. The prepared teeth were divided into three groups (n = 10 each); non-vented control group, occlusal vent group, and lingual vent group. Crowns were fabricated using direct metal laser sintering (DMLS) technology and cemented with resin-based cement. The discrepancy, microleakage, and cement thickness were evaluated under a stereomicroscope. The specimens were subjected to thermal cycling of 5000 cycles, followed by immersion in 2% methylene blue dye. The tooth was sectioned buccolingually to determine cement thickness and microleakage using Tjan's 5-point scale. One-way analysis of variance (ANOVA) was done to find the significant difference among the groups. The post hoc Tukey test was done for intergroup analysis of cement thickness and microleakage. Intergroup comparison for seating discrepancy was done using the Mann–Whitney U test and further correlation was investigated using Pearson's correlation test.
Results: The vented groups showed statistically significant differences (p < 0.05) with better seating, less microleakage, and optimum cement thickness compared to the non-vented groups. Mean seating discrepancy was the lowest for occlusal vent group II (11.13 ± 10.13 µm), followed by lingual vent group III (25 ± 18.47 µm), and highest for control group I (104.28 ± 28.78 µm). The mean microleakage score was lowest for lingual vent group III (0.9 ± 0.46), followed by occlusal vent group II (1.1 ± 0.45), and highest for the control group I (3.3 ± 0.91). Mean cement thickness values were lowest for occlusal vent group II (110.4 ± 9.96 µm), followed by lingual vent group III (110.6 ± 16.82 µm), and highest for control group I (199.01 ± 25.79 µm). A nonsignificant difference was found between the two vented groups for all three parameters (p > 0.05).
Conclusion: Both the vented groups show less seating discrepancy, less microleakage, and less cement thickness as compared to the non-vented control group. A high, positive, and significant correlation was observed between microleakage and cement thickness for all three groups.
Piwowarczyk A, Lauer HC, Sorensen JA. Microleakage of various cementing agents for full cast crowns. Dent Mater 2005;21(5): 445–453. DOI: 10.1016/j.dental.2004.07.009
Saini N, Kumar S, Aggarwal R, et al. Comparative analysis of marginal accuracy of complete crowns fabricated by using ringless and metal ring investment systems: an in vitro study. J Contemp Dent Pract 2020;21(8),852–856. DOI: 10.5005/jp-journals-10024-2902
Hamza TA, Ezzat HA, El-Hossary MM, et al. Accuracy of ceramic restorations made with two CAD/CAM systems. J Prosthet Dent 2013;109(2):83–87. DOI: 10.1016/S0022-3913(13)60020-7
Paul N, Raghavendra Swamy KN, Dhakshaini MR, et al. Marginal and internal fit evaluation of conventional metal-ceramic versus zirconia CAD/CAM crowns. J Clin Exp Dent 2020;12(1):e31–e37. DOI: 10.4317/medoral.55946
Small B. The vented crown: a pictorial case report. Oper Dent 2013;38(2):113–11. DOI: 10.2341/11-463-T
Cruz MA, Sorenson JA, Johnson WK, et al. Effect of venting and seating techniques on the cementation of complete coverage restorations. Oper Dent 2008;33(6):690–695. DOI: 10.2341/08-19
McAllister BS. The rationale for the vented-crown technique and its application in today's dental practice. Oper Dent 2008;33(2):116–120. DOI: 10.2341/08-SA1
Patel D, Invest JC, Tredwin CJ, et al. An analysis of the effect of a vent hole on excess cement expressed at the crown-abutment margin for cement-retained implant crowns. J Prosthodont 2009;18(1):54–59. DOI: 10.1111/j.1532-849X.2008.00374.x
Clark MT, Richards MW, Meiers JC. Seating accuracy and fracture strength of vented and non-vented ceramic crowns luted with three cements. J Prosthet Dent 1995;74(1):18–24. DOI: 10.1016/s0022-3913(05)80223-9
Habib SR, Ali M, Al Hossan A, et al. Effect of cementation, cement type and vent holes on fit of zirconia copings. Saudi Dent J 2019;31(1): 45–51. DOI: 10.1016/j.sdentj.2018.09.001
Rossetti PH, de Carvalho RM, De Goes MF, et al. Correlation between margin fit and microleakage in complete crowns cemented with three luting agents. J Appl Oral Sci 2008;16(1):64–69. DOI: 10.1590/s1678-77572008000100013
Cristian AC, Jeanette L, Francisco MR, et al. Correlation between microleakage and absolute marginal discrepancy in Zirconia crowns cemented with four resin luting cements: an in vitro study. Int J Dent 2016;2016:8084505. DOI: 10.1155/2016/8084505
Herrera M, Catalán A, Flores M, Martínez A. Marginal discrepancy and microleakage in crown-copings fabricated by three CAD/CAM systems: an in vitro study. Open j stomatol 2012;2(3):163–169. DOI: 10.4236/ojst.2012.23030
Eftekhar Ashtiani R, Farzaneh B, Azarsina M, et al. Microleakage of four dental cements in metal ceramic restorations with open margins. Iran Red Crescent Med J 2015;17(11):e19611. DOI: 10.5812/ircmj.19611
Shillingburg, H. T. 2012. Fundamentals of fixed prosthodontics (4th ed.). Quintessence Publishing.
Zaugg LK, Meyer S, Rohr N, et al. Fracture behavior, marginal gap width, and marginal quality of vented or pre-cemented CAD/CAM all-ceramic crowns luted on Y-TZP implants. Clin Oral Implants Res 2018;29(2):175–184. DOI: 10.1111/clr.13075
Muthanna I, Nayyef, Ibraheem A. Marginal microleakage of monolithic zirconia crowns using different marginal cement space thickness and luting cements. J Res Med Dent Sci 2021;9(7):17–22. PMID: 35037730.
Shah R, Shah D. An evaluation of microleakage under crowns cemented with different luting agents. J Adv Oral Res 2012;3(3):24–28. DOI: 10.1177/2229411220120305
Robaian A, Maawadh A, Alghomlas ZI, et al. Evaluation of the marginal microleakage of CAD-CAM compared with conventional interim crowns luted with different types of cement: an in-vitro study. Niger J Clin Pract 2021;24(6):828–832. DOI: 10.4103/njcp.njcp_374_20
Tjan AH, Li T. Seating and retention of complete crowns with a new adhesive resin cement. J Prosthet Dent 1992;67(4):478–483. DOI: 10.1016/0022-3913(92)90076-m
Kosaka S, Kajihara H, Kurashige H, et al. Effect of resin coating as a means of preventing marginal leakage beneath full cast crowns. Dent Mater J 2005;24(1):117–122. DOI: 10.4012/dmj.24.117
Pilo R, Cardash HS. In vivo retrospective study of cement thickness under crowns. J Prosthet Dent 1998;79(6):621–625. DOI: 10.1016/s0022-3913(98)70067-8
Handa M, Marya P, Gupta V, et al. Comparative evaluation of microleakage of metallic copings luted with three different commercially available luting cements: an in vitro study. J Indian Prosthodont Soc 2021;21(1):57–65. DOI: 10.4103/jips.jips_19_20
Romão W Jr, Miranda WG Jr, Cesar PF, et al. Correlation between microleakage and cement thickness in three class II inlay ceramic systems. Oper Dent 2004;29(2):212–218. PMID: 15088734.
Alaghemand H, Abolghasemzadeh F, Pakdel F, et al. Comparison of microleakage and thickness of resin cement in ceramic inlays with various temperatures. J Dent Res Dent Clin Dent Prospects 2014;8(1):45–50. DOI: 10.5681/joddd.2014.008
Kansal R, Rani S, Kumar M, et al. Comparative evaluation of shear bond strength of newer resin cement (RelyX ultimate and RelyX U200) to Lithium disilicate and Zirconia ceramics as influenced by thermocycling. Contemp Clin Dent 2018;9(4):601–606. DOI: 10.4103/ccd.ccd_601_18
Gundogdu M, Aladag LI. Effect of adhesive resin cements on bond strength of ceramic core materials to dentin. Niger J Clin Pract 2018;21(3):367–374. DOI: 10.4103/njcp.njcp_10_17
Ashy LM, Marghalani H. Internal and marginal adaptation of adhesive resin cements used for luting inlay restorations: an in vitro micro-CT study. Materials (Basel) 2022;15(17):6161. DOI: 10.3390/ma15176161
