title: Evaluation of experimental coating to improve the zirconia-veneering ceramic bond strength.
abstract: OBJECTIVE
  To evaluate the shear bond strength (SBS) between zirconia and veneering ceramic following different surface treatments of zirconia. The efficacy of an experimental zirconia coating to improve the bond strength was also evaluated.
  
  
  METHODS
  Zirconia strips were fabricated and were divided into four groups as per their surface treatment: polished (control), airborne-particle abrasion, laser irradiation, and application of the experimental coating. The surface roughness and the residual monoclinic content were evaluated before and after the respective surface treatments. A scanning electron microscope (SEM) analysis of the experimental surfaces was performed. All specimens were subjected to shear force in a universal testing machine. The SBS values were analyzed with one-way ANOVA followed by Bonferroni post hoc for groupwise comparisons. The fractured specimens were examined to observe the failure mode.
  
  
  RESULTS
  The SBS (29.17 MPa) and roughness values (0.80) of the experimental coating group were the highest among the groups. The residual monoclinic content was minimal (0.32) when compared to the remaining test groups. SEM analysis revealed a homogenous surface well adhered to an undamaged zirconia base. The other test groups showed destruction of the zirconia surface. The analysis of failure following bond strength testing showed entirely cohesive failures in the veneering ceramic in all study groups.
  
  
  CONCLUSIONS
  The experimental zirconia surface coating is a simple technique to increase the microroughness of the zirconia surface, and thereby improve the SBS to the veneering ceramic. It results in the least monoclinic content and produces no structural damage to the zirconia substructure.
authors: Department of Prosthodontics and Implantology, M A Rangoonwala College of Dental Sciences and Research Centre, Azam Campus, Pune, India.
authors: Jay D
authors: JD
authors: Matani
authors: Mohit
authors: M
authors: Kheur
authors: Shantanu Subhashchandra
authors: SS
authors: Jambhekar
authors: Parag
authors: P
authors: Bhargava
authors: Aditya
authors: A
authors: Londhe
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry* / Q000528:radiation effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000528:radiation effects; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003764:Dental Materials / Q000737:chemistry* / Q000528:radiation effects; D003775:Dental Polishing / Q000379:methods; D003799:Dental Stress Analysis / Q000295:instrumentation; D003801:Dental Veneers; D006801:Humans; D053844:Lasers, Solid-State; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D033081:Shear Strength; D017655:Silicon Compounds / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D017554:Carbon Compounds, Inorganic; D020099:Coated Materials, Biocompatible; D003764:Dental Materials; D017655:Silicon Compounds; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide; C022088:silicon carbide
keywords: All-ceramic; delamination; shear bond strength; zirconia