Effect of the applied power of atmospheric pressure plasma on the adhesion of composite resin to dental ceramic.
OBJECTIVE
To evaluate the effect of applied power on dental ceramic bonding of composite resin using nonthermal atmospheric pressure plasma (APP).


METHODS
A pencil-type APP torch was used to modify the surface chemical composition and hydrophilicity of dental ceramic and to improve the adhesion of composite resin to the surface. The effect of the applied power on chemical changes of the plasma polymer on a ceramic surface and the adhesive strength between the composite resin and feldspathic porcelain were examined. Adhesion was evaluated by comparing shear bond strengths (SBS) using the iris method. The chemical composition of the plasma polymer deposited on the ceramic surface was evaluated using x-ray photoelectron spectroscopy (XPS). Hydrophilicity was evaluated by contact angle measurements. The fracture mode at the interface was also evaluated.


RESULTS
The APP treatment was effective and the SBS of the experimental groups were significantly higher than those of the negative control group (p < 0.05). Moreover, the SBS obtained with the APP treatment at the highest input voltage was statistically similar to the gold standard of HF etching and silane coupling-agent coating. Two-thirds of the fractures observed in the specimens bonded with application of APP were mixed and cohesive fractures.


CONCLUSIONS
Application of APP enhanced adhesion by producing carboxyl groups on the ceramic surface and as a result by improving surface hydrophilicity. The carboxyl group contents in the plasma polymer on the ceramic surface increased as the applied power increased.
Department of Dental Biomaterials Science, Seoul National University Graduate School, Seoul, Korea.
Geum-Jun
GJ
Han
Sung-No
SN
Chung
Bae-Hyeock
BH
Chun
Chang-Keun
CK
Kim
Kyu-Hwan
KH
Oh
Byeong-Hoon
BH
Cho
D000134:Acid Etching, Dental / Q000379:methods; D000538:Aluminum Silicates / Q000737:chemistry; D001274:Atmospheric Pressure; D002245:Carbon Dioxide / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods; D005609:Free Radicals / Q000737:chemistry; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D056951:Photoelectron Spectroscopy; D058626:Plasma Gases / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry; D033081:Shear Strength; D012821:Silanes / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D017155:Wettability
D000538:Aluminum Silicates; D003188:Composite Resins; D003764:Dental Materials; D005609:Free Radicals; D058626:Plasma Gases; D011109:Polymethacrylic Acids; D017680:Potassium Compounds; D012821:Silanes; C082340:Vita Mark II; D003776:Dental Porcelain; C016447:feldspar; D002245:Carbon Dioxide; C041069:carboxyl radical; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D006858:Hydrofluoric Acid