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restorative section

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has the property to combine directly with metal oxides as ZrO 2 , retention of crown has to rely on the geometric principles; paral-
Al2O , etc. (Figure 1). In the same time it provides the highest bond lelism and minimum taper, adequate axial height, 360 degrees cov-
3
strength to dentin among the functional monomers from adhesive erage etc making the prep execution very critical.
systems. The cementation protocol on natural teeth supposes 2. GIC shows water sorption, so it raises concerns about the
dentin conditioning, zirconia surface conditioning with a special microleakage and hydronium ion contamination leading to LTD
MDP primer and MDP or non- MDP composite cement (Figure 2). and eventual fracture of the restoration.
In vitro studies indicated that the presence of MDP monomer in
both ceramic primer and resin cement provides higher bond CONCLUSION
strength than the usage of only one of them, MDP primer or MDP It is very clear that the most reliable method especially when using
resin cement. translucent Zr would be etched Zr surface along with phosphate
2. The second method called “Silicization” is used in laboratories primers especially the MDP. The usage of RMGI also provides an
and is an airborne particle abrasion using 50-110 m Al2O3 coated increasing alternative more so when used with mechanically etched
with silica. Due to the very high speed of these particles, about internal surface.
1000km/h, these are embedded on the ceramic surface with the
result of a chemically silica- modified surface. Furthermore this sur-
face is acting as a usual glass ceramic surface, and resin cement
bonds to it via silane coupling agent. It’s similar to the tri-biochem- About the AUTHOR
ical silica coating.
3. Third method is a combination of the two Dr Sachin Deep Singh did his graduation from G.D.C & H,
Mumbai, followed by post graduation in Prosthodontics
ZIRCONIA CEMENTATION WITH GLASS IONOMER CEMENTS from K.G.M.C, Lucknow. He currently runs courses on dental
In recent years glass ionomer cements have become very popular for implants and full mouth rehabilitation at Four Dimensions
zirconia cementation as they are the most conventional and cost Dental, Gurgaon. He maintains a private practice in New
effective option. Despite being a popular option there are certain Delhi focusing on Implantology and Aesthetic Dentistry. He
points of concern has been active in CDE for more than 15 years now and has
1. There is no bonding between the GIC and zirconia so the lectured extensively in national and international platforms.

28 Dental Practice // January-February 2021 // Vol 17 No 4