ABSTRACT
BACKGROUND: The authors analyzed the in vitro and in vivo performance of lithium disilicate glass-ceramic (LDGC) restorations and yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) (that is, zirconium oxide) restorations with regard to reliability, clinical performance and abrasion resistance. METHODS: In the in vitro study, four authors subjected samples of LDGC, Y-TZP and metal-ceramic crowns to step-stress fatigue testing. Four investigators assessed the in vivo clinical performance of LDGC and zirconium oxide-based restorations at four and seven years, respectively. In addition, one author conducted a randomized, controlled clinical trial to analyze the volumetric loss of enamel and ceramic antagonist surfaces. RESULTS: The LDGC crowns exhibited the highest fatigue load-to-failure values in the in vitro analysis. The results of the in vivo assessment showed that the clinical performance of the LDGC restorations at four years was comparable to that of the zirconium oxide-based crowns at seven years. The results of the in vivo, randomized, controlled clinical trial showed that LDGC crowns were not only resistant to wear, but also were wear friendly to enamel antagonist surfaces. CONCLUSIONS: The LDGC crowns in the in vitro and in vivo studies exhibited high durability, and they were wear friendly to opposing natural dentition. CLINICAL IMPLICATIONS: LDGC and zirconium oxide-based crowns are a clinically acceptable means of treating teeth that require full-coverage restorations. In addition, LDGC materials exhibit excellent clinical performance, as well as demonstrate acceptable abrasion compatibility with the opposing natural dentition.
Subject(s)
Dental Materials/chemistry , Dental Porcelain/chemistry , Dental Prosthesis , Zirconium/chemistry , Adult , Ceramics/chemistry , Computer-Aided Design , Crowns , Dental Abutments , Dental Enamel/pathology , Dental Restoration Failure , Dental Restoration Wear , Dental Restoration, Permanent , Dental Stress Analysis/instrumentation , Dental Veneers , Denture, Partial, Fixed , Female , Follow-Up Studies , Humans , Male , Materials Testing/methods , Metal Ceramic Alloys/chemistry , Middle Aged , Randomized Controlled Trials as Topic , Stress, Mechanical , Tooth Abrasion/etiology , Young Adult , Yttrium/chemistryABSTRACT
Bonding to enamel and dentin has been among the most significant advancements in dentistry in the last five decades; extensive research and product development have resulted in more adhesive options. However, bonding to enamel and dentin still proves to be challenging, and selecting the correct product for a clinical application can be confusing. An incorrect choice can lead to insufficient bond strength. Day-to-day clinical factors, such as the presence of enamel, superficial dentin, or carious dentin, as well as contamination by saliva, blood, or bleaching agents, can cause bonding agents to be technique sensitive-they may fail prematurely if steps are not followed meticulously. This article attempts to simplify the selection process for enamel and dentinal bonding and summarize clinically relevant bonding information that will help produce consistently successful results.
