Re-intervention in glass ionomer restorations: what comes next?

The aim of this study is to report the subsequent treatment provided, over the 11 years' data available, when a re-intervention was considered clinically necessary on a glass ionomer (GI) restoration.

A detailed sample of treatment records of patients has been established at the Dental Practice Division of the NHS Business Services Authority, consisting of records containing directly placed restorations for adult patients from January 1991. This database contains the records of over half a million restorations. For each direct restoration placed, the subsequent history of that tooth was consulted, for the period up to December 2001, and the restorations divided into three groups: amalgam, composite and GI, the latter being subdivided into anterior teeth, premolars, and molars.

Data on 164,036 directly placed restorations were analyzed. Results indicated that, for amalgam and composite restorations, the subsequent treatment was likely to be another restoration in the same material. For GI (24,947 restorations), only one third of restorations, overall, were followed by another GI. In anterior teeth, GI restorations were more often followed by composite than by GI, this trend increasing with increasing time interval since restoration. For premolar teeth, the GI restoration was most likely to be followed by another GI within 4 years, with an increasing trend towards re-intervention by an amalgam or composite in older restorations. For molar teeth, GI restorations were more likely to be followed by an amalgam restoration.

For GI restorations, on re-intervention, there is variation in the next restoration material used according to tooth position and time interval to re-intervention. GI restorations in anterior and molar teeth are not likely to be followed by another GI restoration.