StomatologyEduJ 5(1) SEJ_5_2_site | Page 38
ORTHODONTICS
BONDING ORTHODONTIC RESIN CEMENT TO ZIRCONIUM OXIDE UNDER
ORTHODONTICS LOAD AND THERMOCYCLING EFFECT
Hind S. Hussein 1a , Nader Abdulhameed 1b , Chiayi Shen 1c , Calogero Dolce 2d , Jean-François Roulet 1e*
Department of Restorative Dental Sciences, College of Dentistry, University of Florida
Department of Orthodontics, College of Dentistry, University of Florida
1
2
BDS, Courtesy Clinical Assistant Professor
BDS, MS, PhD Student, Clinical Assistant Professor
c
PhD, Associate Professor
d
DDS, PhD, Professor
e
Dr med dent, Dr hc, Professor, Director of Center for Dental Biomaterials
a,
b
ABSTRACT
DOI: 10.25241/stomaeduj.2018.5(2).art.4
Purpose: Evaluate the microshear bond strength (µSBS) of orthodontic resin cement to
monolithic zirconium oxide ceramic (MZ) under orthodontic load (OL) and thermocycling
(TC) effect.
Materials and Methods: Glazed MZ blocks (Zenostar, Ivoclar Vivadent) were tested after
air abrasion with 30-µm silica coated aluminum oxide (Al 2 O 3 ) particles (CoJet, 3M ESPE). The
specimens were randomly divided into 4 groups (n = 15): G1, OL with TC; G2, OL without
TC; G3 no OL with TC; and G4, no OL, no TC (control). Orthodontic cement cylinders (Heliosit
Orthodontic, Ivoclar Vivadent) were bonded to the primed samples (Monobond Plus,
Ivoclar Vivadent) using the Ultradent SBS system and light cured (SmartLite Max, Dentsply
Sirona, 1400 mW/cm 2 , 40 s). G1 and G2 were subjected to 70 ± 15 N load perpendicular to
the cylinder axis, G1 and G3 were thermo-cycled (5000 cycles 5-55°C, 90 s/cycle). G2 and
G4 were stored in distilled water at 37 ± 1°C. The specimens were subjected to µSBS test
(crosshead speed 0.5 mm/min). Data were analyzed using two-way ANOVA, and one-way
ANOVA and Tukey test (HSD).
Results: Two-way ANOVA for µSBS values (MPa) showed significant (p = 0.0004) load effects,
but not thermal effect (p = 0.2455) with significant load/thermocycling interactions (p <
0.0001). The ranking of the single groups by Tukey test (α = 0.05) showed that G1 exhibited
the highest µSBS (8.4 ± 2.8 MPa), G4 (6.3 ± 1.1 MPa) and G2 (5.8 ± 1.1 MPa) as a group was
second, and G2 and G3 (4.7 ± 1.1 MPa) as a group was the lowest.
Conclusion: G1, which is the closest to clinical reality, yielded the best results.
Keywords: orthodontics, dental materials, orthodontic resin cement, monolithic zirconium oxide
ceramic, microshear bond strength test.
1. Introduction
Due to the patients’ increased esthetic demands and
the development of technology in dental materials,
porcelain fused to metal (PFM) crowns and bridges are
being replaced by glass based ceramic materials and
monolithic Zirconium oxide (MZ) [1]; they are more
esthetic, biocompatible, resistant to wear, show low
thermal conductivity, and are color stable [2]. However,
despite these advantages, the brittle nature of these
materials restricts their use [3].
Therefore, there is a need for new materials which have
the same esthetic properties as glass based all ceramic
materials and a strong framework like PFM for fixed
dental prosthesis (FDPs). The introduction of zirconium
oxide fulfilled these requirements [4]. The advantages
of zirconium oxide include high fracture resistance and
high flexural strength (> 1000 MPa), which allowed for
thinner restorations. Furthermore the material can be
stained which allows better esthetic results [5]. These
properties make it a very good candidate for aesthetic
FDPs. The tetragonal zirconia polycrystals (TZP),
especially 3 mol % Y 2 O 3 stabilized zirconia (3Y-TZP)
has been used as a material for dental and medical
102
OPEN ACCESS This is an
Open Access article under the CC
BY-NC 4.0 license.
Peer-Reviewed Article
Citation: Hussein HS, Abdulhameed N,
Shen C, Dolce C, Roulet J-F. Bonding of
orthodontic resin cement to zirconium
oxide under load and thermocycling.
Stoma Edu J. 2018;5(2):102-108.
Academic Editor: Diana Dudea,
DDS, PhD, Professor, “Iuliu Hațieganu”
University of Medicine and Pharmacy
Cluj-Napoca, Cluj-Napoca, Romania
Received: May 28, 2018
Revised: June 06, 2018
Acccepted: June 11, 2018
Published: June 12, 2018
*Corresponding author: Professor
Jean-François Roulet, DMD, PhD, Dr hc
Center for Dental Biomaterials, College
of Dentistry, University of Florida 1395
Center Drive, Room D9-26, Gainesville,
FL 32608 Gainesville, FL 32608, USA Tel:
+1 352 273 5850; Fax: +1 352 846 1643,
e-mail: [email protected]
Copyright: © 2018 the Editorial Coun-
cil for the Stomatology Edu Journal.
restorations [6]. Previous studies have reported that
the life expectancy of (3Y-TZP) zirconium oxide when
compared to PFM FDPs for posterior indication, is
shorter because of the delamination and chipping
of veneering ceramic; to overcome this problem, the
monolithic zirconium oxide (MZ) was introduced to the
dental market [1,2,4,7].
Full contour MZ FDPs are produced using CAD/CAM
technologies. The restorations are milled from blocks
which can be used either glazed or polished for better
esthetic results [8]. Although polishing may provide
sufficient esthetic appearance by decreasing the
surface roughness, technicians like to glaze the ZrO 2
surface to improve the esthetic properties. With this
process, the glass will infiltrate the zirconium oxide [9].
Since the number of adult patients who have been
seeking orthodontic treatment is increasing [9], it
means that the orthodontist will sometimes apply
orthodontic brackets on dental restora