Clinical performance of a new glass ionomer based restoration system: A retrospective cohort study

Objectives This retrospective clinical study evaluated the suitability of a glass ionomer system as a permanent restoration material in posterior cavities. Methods 26 Class I (1-surface (S1)) and 125 Class II (84 2-surface (S2), 41 3- and 4-surface (S3+)) restorations were placed in permanent molars (n=94) and premolars (n=57) in 43 patients in 6 dental practices. Restorations were evaluated at 4.5× magnification using modified USPHS criteria. Statistical analysis was performed using the Pearson's Chi-square-test (p ≤ 0.05). Results The median age of the restorations was 24 months. No failures were observed. The original volume of the restoration was retained in 88.5% of the S1, in 64.2% of the S2 and in 53.7% of the S3+ restorations. A distinct volume loss in S1 restorations was evident in 3.8%. A visible and perceptible roughness was shown in 11.5% of the S1, in 14.3% of the S2 and in 24.4% of the S3+ restorations. Marginal disintegrities occurred in none of the S1, in 1.2% of the S2 and in 7.3% of the S3+ restorations. A distinct marginal discoloration was found less than 1%. Conclusions Within the limitations of this study it can be concluded that EQUIA can be used as a permanent restoration material for any sized Class I and in smaller Class II cavities. However, results of ongoing prospective studies shall provide a more exact indication definition in Class II situations. Significance Modern glass ionomer systems may not only serve as long-term temporaries, but also as permanent restorations in posterior teeth.