| dc.description.abstract | The components of RPD are the denture base/connector, retainer, saddle and artificial
teeth. Denture bases are generally made from metals such as cobalt chromium/Co-Cr
or from thermosetting polymers such as polymethyl methacrylate (PMMA) or better
known as acrylic resin. Due to the lower cost, RPD with hot polymerized acrylic resin
is widely used, but acrylic has low fracture resistance. To overcome the liability of
previous material, cobalt-chromium/Co-Cr is generally used as the metal framework
with its excellent mechanical properties. One of the limitations of metal frames is the
inescapable appearance of metal clasps, which makes it less aesthetically pleasing.
Like most patients, elderly patients with edentulus are partially aesthetically
conscious and seek treatment that not only rehabilitates oral function, but also
enhances esthetics. Polyetheretherketone is a linear polycyclic aromatic
semicrystalline thermoplastic polymer obtained from the union of ketone and ether
functional groups between aryl rings. PEEK has a density, coefficient of elasticity
and compressive strength similar to that of human hard tissue, which makes it a
suitable choice for denture dentures. PEEK is an inert material, makes it difficult to
bond to others dental material. Surface modification of PEEK is one of the main
focuses prior to its clinical application. The aim of this study is to examine the effect
of surface treatment and thermocycling on the shear bond strength of PEEK
frameworks and PMMA saddles. The CAD/CAM technique was used for the
manufacture of PEEK samples in this study so that the dimensions of the samples
were accurate and precise. The PEEK material used contains 5 Wt% titanium oxide
(TiO2) nanoparticle filler for better mechanical resistance. Thirty pieces of PEEK
samples with a size of 10 x 10 mm and a thickness of 3 mm were made according to
ISO 29022, then divide into groups based on the type of surface treatment (chemical,
mechanical and combined). Disc-shaped wax with a diameter of 5 mm and a
thickness of 3 mm the 3 groups with a total of 30 samples were then placed in centre
of the PEEK sample. Flasking, dewaxing and packing of heat polymerized acrylic
resin were carried out by mixing powder and liquid with a ratio of 3:1 and put in
waterbath according to the manufacturer's directions. Then each group of samples
was further divided into two groups: without thermocycling and with 5000 cycles
thermocycling to simulate 5 years denture usage. Shear bond strength test was then
carried out. From the test result, the combination surface treatment group without
thermocycling gave the highest shear bond strength, the shear bond strength value of
the chemical surface treatment group with thermocycling had the lowest shear bond
value. Failure mode of PEEK with heat polymerized acrylic resin in all thermocycling
groups was adhesive failure type and only 6.7 % cohesive failure in the total number
of samples. The clinical implication of this study is that PEEK can be used as a
potential alternative material for a more aesthetically pleasing GTSL framework. The
use of a combination of sandblasting using 110 μm Al2O3 particles with a pressure of 0.4 MPa (4 Bar) and visio.link priming material is the most optimal surface treatment
method for PEEK framework bonding to hot polymerized acrylic resin saddles and
can be recommended for long-term clinical applications. | en_US |
