title: Effect of resin coating on adhesion and microleakage of computer-aided design/computer-aided manufacturing fabricated all-ceramic crowns after occlusal loading: a laboratory study.
abstract: This study investigated the effect of resin coating and occlusal loading on adhesion and microleakage of all-ceramic crowns. Molars were prepared for an all-ceramic crown and were divided into two groups: non-coated (control) and resin-coated with Clearfil Tri-S Bond. Crowns were fabricated using CEREC 3 and cemented using Clearfil Esthetic Cement. After 24 h of storage in water, the restored teeth in each group were divided into two subgroups: unloaded, or loaded while stored in water. Mechanical loading was achieved with an axial force of 80 N at 2.5 cycles s(-1) for 250,000 cycles. After immersion in Rhodamine B, the specimens were sectioned and processed for microleakage evaluation by confocal microscopy, which was followed by further sectioning for microtensile bond testing. Loading had no significant effect on microleakage in either the resin-coated or non-resin-coated groups. Resin coating did not reduce the microleakage at the dentine interface but increased the microleakage at the enamel interface. All the beams fractured during slicing when non-coated and loaded. The bond strengths of non-coated and unloaded, resin-coated and unloaded, and resin-coated and loaded groups were 15.82 +/- 4.22, 15.17 +/- 5.24, and 12.97 +/- 5.82 MPa, respectively. Resin coating with Clearfil Tri-S Bond improved the bonding of resin cement to dentine for loaded specimens. However, it was not effective in reducing the microleakage, regardless of whether it was loaded or unloaded.
authors.affiliation: Cariology and Operative Dentistry, Department of Restorative Science, Graduate School, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan. nuevo_centro@yahoo.co.jp
authors.forename: Shuzo
authors.initials: S
authors.lastname: Kitayama
authors.forename: Peter
authors.initials: P
authors.lastname: Pilecki
authors.forename: Nasser A
authors.initials: NA
authors.lastname: Nasser
authors.forename: Theodora
authors.initials: T
authors.lastname: Bravis
authors.forename: Ron F
authors.initials: RF
authors.lastname: Wilson
authors.forename: Toru
authors.initials: T
authors.lastname: Nikaido
authors.forename: Junji
authors.initials: J
authors.lastname: Tagami
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Watson
authors.forename: Richard M
authors.initials: RM
authors.lastname: Foxton
mesh_terms: D000134:Acid Etching, Dental; D001732:Bite Force; D002484:Cementation / Q000379:methods; D017076:Computer-Aided Design; D003442:Crowns; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure; D003763:Dental Leakage / Q000145:classification*; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003804:Dentin / Q000648:ultrastructure; D005456:Fluorescent Dyes; D006801:Humans; D008422:Materials Testing; D018613:Microscopy, Confocal; D019279:Resin Cements / Q000737:chemistry*; D012235:Rhodamines; D013314:Stress, Mechanical; D013718:Tensile Strength; D013997:Time Factors; D019231:Tooth Preparation, Prosthodontic; D014867:Water / Q000737:chemistry
chemical_list: C515604:Clearfil Tri-S Bond; D005456:Fluorescent Dyes; D019279:Resin Cements; D012235:Rhodamines; C530542:clearfil esthetic cement; D014867:Water; D003776:Dental Porcelain; C029773:rhodamine B