title: Marginal integrity of partial ceramic crowns within dentin with different luting techniques and materials.
abstract: This in vitro study evaluated the marginal integrity of partial ceramic crowns (PCCs) luted with or without a resin-coating and compared the results with the marginal sealing of a recently introduced self-adhesive universal resin cement. PCC preparations were performed on 84 extracted human molars, with proximal margins placed 1 mm below the cemento-enamel junction. The PCCs were fabricated from Vita Mark II ceramic (Vita) using the Cerec-3 Unit (Sirona). The prepared teeth were assigned to three groups: (1) conventional luting technique (n=36), (2) resin-coating luting technique (n=36) or (3) recently introduced self-adhesive universal resin cement (n=12). Within these three groups, the following materials were applied: (1) Excite/Variolink II (EVC), ED-Primer/Panavia-F2.0 (PAC), Syntac Classic/ Variolink II (SYC); (2) Excite/Variolink II with Excite/Tetric Flow resin-coating (EVR), ED-Primer/Panavia-F2.0 with Clearfil SE-Bond/ Protect-Liner F resin-coating (PAR), Excite/ Variolink II with Syntac Classic/Tetric Flow resin-coating (SYR); (3) RelyX Unicem (REX). After thermocycling and mechanical loading (TC: 5000 cycles at 5 degrees C/55 degrees C; 30 seconds/cycle; ML:500000 cycles at 72.5 N, 1.6 Hz), microleakage was assessed by evaluating silver staining (%) on multiple tooth sections. Ceramic/composite-, resin-coating/composite- (where applicable) and dentin/composite-interfaces were evaluated separately. The data were statistically analyzed with the Mann-Whitney-U-test and the Error Rates Method. In Groups 1 and 2, the evaluation of microleakage at dentin showed better marginal integrity when the resin-coating technique was applied (EVR, PAR, SYR: 18-53%) than within the conventional luting technique group (EVC, PAC, SYC: 58-67%). However, the lowest microleakage values were found for RelyX Unicem (REX: 15%). In conclusion, resin-coating may improve the marginal sealing within dentin, depending on the materials used. Luting with a self-adhesive universal resin cement showed the best marginal sealing of all groups.
authors.affiliation: University of Regensburg-Dental School, Department of Operative Dentistry and Periodontology, Regensburg, Germany. Frederike.Schenke@klinik.uni-regensburg.de
authors.forename: Frederike
authors.initials: F
authors.lastname: Schenke
authors.forename: Karl-Anton
authors.initials: KA
authors.lastname: Hiller
authors.forename: Gottfried
authors.initials: G
authors.lastname: Schmalz
authors.forename: Marianne
authors.initials: M
authors.lastname: Federlin
mesh_terms: D002484:Cementation / Q000379:methods*; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003804:Dentin / Q000033:anatomy & histology*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D019237:Tooth Cervix / Q000033:anatomy & histology; D019231:Tooth Preparation, Prosthodontic / Q000379:methods
chemical_list: C438313:Clearfil SE Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C500742:ED Primer II; C420130:Excite cement; D008689:Methacrylates; C438843:Panavia-Fluoro; C409388:Protect Liner F; C483701:Rely X Unicem; D019279:Resin Cements; C078484:Syntac dentine adhesive; C082340:Vita Mark II; C452226:tetric flow composite resin; D003776:Dental Porcelain; C103502:Variolink