title: Glass-ceramics bonding in geriatric patients: comparison with young teeth.
abstract: OBJECTIVE
  The aim of the study was to assess whether in geriatric patients, the shear bond strength (SBS) of glass-ceramics differed when compared to young controls.
  
  
  BACKGROUND
  In the need of aesthetic restorations for geriatric patients, reliable bonding of glass-ceramics should be accomplished; however, glass-ceramics bonding on aged tooth structures is still unclear.
  
  
  METHODS
  Sixty extracted molars from young and geriatric patients [18-25 (Y), and 65-80 (O)] were cut buccolingually to prepare enamel (E) and dentin (D) surfaces. Both surfaces were randomly divided into three groups according to the resin cements: Variolink II (V); Superbond (S); and Clearfil Esthetic Cement (C) (n = 10). Disc-shaped glass-ceramics (IPS E-max Press) (n = 120) were prepared. Specimens were bonded and subjected to thermocycling. SBS test was performed using a universal testing machine (0.5 mm/min). After debonding, the surfaces were examined using stereomicroscope and scanning electron microscope. Data were statistically analysed with Kolmogorov-Smirnov, Levene, anova and Bonferroni tests (p = 0.05).
  
  
  RESULTS
  There were no significant differences between the old and young teeth surfaces. V showed the highest SBS [MPa(SD)] on both enamel and dentin [36.7 (6.5) (YE), 23.2 (13.2) (YD), 32.1 (16.2) (OE), 25.5 (8.6) (OD), respectively]. Significant differences were observed between resin cements (p < 0.05). The failure types were 43% adhesive between tooth and cement, 48% mix, 9% adhesive between cement and ceramic, regardless of cement type.
  
  
  CONCLUSIONS
  In geriatric patients, the shear bond strength of glass-ceramics did not differ when compared to that of young controls. On the dentin surface, etch-rinse resin cements appear to be more appropriate for glass-ceramics bonding.
authors.affiliation: Department of Prosthodontics, School of Dentistry, Ege University, Bornova, Izmir, Turkey.
authors.forename: Ayşe Gözde
authors.initials: AG
authors.lastname: Türk
authors.affiliation: Department of Prosthodontics, School of Dentistry, Ege University, Bornova, Izmir, Turkey.
authors.forename: Ebru
authors.initials: E
authors.lastname: Cal
authors.affiliation: Department of Prosthodontics, School of Dentistry, Ege University, Bornova, Izmir, Turkey.
authors.forename: Sena
authors.initials: S
authors.lastname: Unal
authors.affiliation: Department of Oral and Maxillofacial Radiology, School of Dentistry, Ege University, Bornova, İzmir, Turkey.
authors.forename: Pelin
authors.initials: P
authors.lastname: Güneri
authors.affiliation: Department of Prosthodontics, School of Dentistry, Ege University, Bornova, Izmir, Turkey.
authors.forename: Mübin
authors.initials: M
authors.lastname: Ulusoy
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Ege University, İzmir, Turkey.
authors.forename: Meltem
authors.initials: M
authors.lastname: Ozden
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002516:Ceramics / Q000627:therapeutic use*; D001840:Dental Bonding / Q000379:methods*; D003799:Dental Stress Analysis; D003801:Dental Veneers; D006801:Humans; D008963:Molar; D019279:Resin Cements / Q000627:therapeutic use; D033081:Shear Strength; D013499:Surface Properties; D055815:Young Adult
chemical_list: D019279:Resin Cements
keywords: adhesive; ageing; bonding; glass-ceramics; resin cements