The efficacy of modern adhesive dental materials relies to a great extent on the quality of the bonding systems. Questions have been raised about the efficacy of bonding agents when used with zircona. The aim of this trial was to compare two different bonding systems for the placing of zircona ceramic resin-bonded fixed partial dentures (RBFPDs) with a cantilevered single-retainer design.
Patients over the age of 14, with at least average oral hygiene, who did dot suffer with bruxism, or participate in contact sport, with no untreated advanced periodontitis, and with one caries free or almost caries free abutment tooth with sufficient space for the retainer wing available were eligible.
Patients were randomised to have at least one (no more than 2) anterior RBFPD with a cantilevered single-retainer design made from zirconia ceramic and inserted using either a phosphate monomer containing resin (Panavia 21 TC; N = 16) without any primer or using an adhesive bonding system with a phosphoric acid acrylate primer for the zirconia ceramic (Multilink–Automix bonding system with Metal/ Zirconia primer; N = 14). Main outcomes were times to debonding, failure or other minor complications.
- The RBFPDs were observed for 41.7 months (min. 9.4, max. 55.9)
- One debonding occurred in each group (after 11.1 months with Panavia and after 20.8 months with Multilink).
- one minor complication occurred.
- overall three-year Kaplan–Meier survival rate was 93.1%
The authors concluded
Cantilevered all-ceramic RBFPDs made from zirconia ceramic present a promising treatment alternative for the replacement of missing incisors. After 3 years of clinical service a phosphate monomer modified resin cement as well as a modern resin cement with a special primer for zirconia ceramic showed successful clinical results.
This study was supported by Ivoclar Vivadent, Schaan, Liechtenstein.
Comment
This is a small study and is likely to have been underpowered as power calculation was based on an anticipated 40% difference in failure rates and only a 70% chance of detecting a difference rather than the more usual 80%.
Links
Sasse M, Eschbach S, Kern M. Randomized clinical trial on single retainer all-ceramic resin-bonded fixed partial dentures: Influence of the bonding system after up to 55 months. J Dent. 2012 Sep;40(9):783-6. Epub 2012 Jun 1. PubMed PMID: 22659339.
