Clinical Evaluations Confirm Longevity of Glass Ionomer Cements
RESPECTFULLY SUBMITTED BY:
Professor L. Sebnem Turkun, Ege University School of Dentistry, Turkey
Professor Sebnem Turkun graduated from Ege University School of Dentistry in 1991. In 1998 she obtained her PhD degree in Restorative Dentistry, became an Associate Professor in 2004 and a Professor in 2009. She is currently working in Ege University School of Dentistry in the Department of Restorative Dentistry as a full time Professor and head of the Restorative Dentistry Department. Her principal areas of interest are adhesive dentistry, aesthetic restorative materials and their clinical performance, antibacterial restorative materials, glass ionomer restoratives and minimal invasive dentistry. She has published many international and national papers in her fields of interest, participates as keynote speaker in many international and national congresses and presents numerous workshops and handson courses. She is a member of the IADR, EDAD, Turkish Restorative Dentistry Association, MI European Board and serves on the European Federation of Conservative Dentistry (EFCD) executive committee. Since 2007, she is the translating editor of the journal Quintessence Turkey and the board member of many international and national dental journals.
“EQUIA by GC excels in long term studies as permanent posterior restorative”
For more than three decades, thousands of clinical studies have been conducted comparing the clinical performance of aesthetic resin based materials. Thanks to these, we now know that if done properly, resin composites perform as well as amalgam restorations in the timeframe of 8 to 10 years. However, with some high caries risk patients, it is literally a crime to place posterior resin restorations before stabilizing the oral environment. What is needed in cases like these is a high wear resistant, long-lasting and fluoride releasing dental material for posterior restorations.
A few years ago, when GC launched its new reinforced glass ionomer material, EQUIA, we wanted to test its long-term clinical performance in comparison to another reinforced and encapsulated glass ionomer, Riva (SDI, Australia). We believed that comparing two materials
in the same group would expedite our ultimate goal of successfully using minimum intervention materials in posterior restorations. So in 2008 we decided to conduct a PhD thesis comparing the clinical performance and some mechanical properties of the two encapsulated and reinforced glass ionomer cements.
The study revealed that the EQUIA Fil system was more successful than Riva when it came to color-match and retention rate after a 6-year clinical period. Despite minor reparable defects, the overall clinical performance of EQUIA Fil was excellent, even in large posterior two-surfaces restorations after a period of 6 years.
As we know very well, conventional glass ionomer cements have a chalky appearance, wear quickly and are easily fractured from the marginal ridges in multi-surface restorations. With the improvement in glass ionomer technology, reinforced and encapsulated glass ionomers were launched in the market, eliminating the problem of wear.
However, aesthetics and fracture resistance remained a great problem which limited the clinical indications of the glass ionomer cement restorations. At that time, EQUIA was developed by GC in combination with a light curing resin coating placed over the restoration immediately after setting. This unique coating protects the glass ionomer material from wear until it fully matures and gives it a shiny, aesthetic look. The most important concern then was its clinical longevity, especially in moderate to large two-surface restorations.
So the most important outcome of this long-term clinical study is that we could destroy the myth that glass ionomer cements wear quickly and therefore were only suitable as provisional posterior restorative materials.
THE IMPACT ON DAY-TO-DAY DENTISTRY
The long-term clinical findings of our study in combination with many others already published, proved that glass ionomer cements are not provisional restorative materials but a bona fide permanent material of choice even in large proximal restorations. These restorations are placed very quickly in bulk and without the need for adhesive systems. When the patient is at high caries risk or isolation of the cavity poses a problem, now the material of choice is a reliable reinforced glass ionomer with resin coating.
In Turkey, the government covers most of the basic dental treatments in dental hospitals or university clinics for insured employees. We have a large amount of patients attending our clinics every day for many reasons, but mostly for caries and periodontal problems. For the past two years national social security has not reimbursed hospitals for glass ionomer restorations because it considers them to be provisional restorations instead of permanent.
However, these patients are in need of a fluoride-releasing restorative material to stabilize their oral environment. For that purpose and for convincing the Ministry of Health that this material is now a proven permanent restorative material, we needed evidence based research and long-term clinical trials. With the published data that are now available in the literature, I think that we will be successful very soon.
The overall clinical performance of EQUIA Fil was excellent even in large posterior two-surfaces restorations after a period of 6 years
THE EQUIA FIL SYSTEM
Nowadays, most of the reinforced and encapsulated glass ionomer materials can be used for a minimum of two years without any problems in posterior teeth with small to moderate cavities.1 However, if color match is a concern for the patient, or if we need a more resistant permanent material for medium to large cavities and if we are looking for a long-term restoration, a more sophisticated brand like EQUIA Fil with a resin coating should be used.2
The EQUIA Fil system is different to other reinforced and encapsulated glass ionomer materials on the market due to its reliable color matching properties and easy handling. The other materials, including Riva, have a chalky appearance, similar to conventional powder liquid glass ionomer cements after placement. EQUIA Fil matures under the resin coating and develops a very hard and resistant consistency as time passes. This fracture resistance is crucial as the material needs to function in the mouth for a long period of time.
Even in larger two- sided restorations, its longevity is better than other glass ionomers and similar to resin composites, as proved in a 4-year clinical study published by my colleagues from Hacettepe University/Turkey [include reference].3
A new version of EQUIA Fil has been launched earlier this year, EQUIA Forte, with further improved color matching and resistance. We are excited to be taking part in a multi-center long-term clinical study alongside universities in Croatia, Italy and Bulgaria to test the clinical efficacy of this material.