Stainless steel crown versus modified open-sandwich restorations for primary molars: a 2-year randomized clinical trial

Objective. The aim of this study was to investigate the clinical performance and survival of stainless steel crown (SSC) restoration and modified open-sandwich technique using resin-modified glass ionomer cement. Design. Randomized clinical trial. Setting. General dental practice. Materials and methods. A total of 87 children aged 4-7 years at baseline with one or more primary molars that have undergone pulp therapy were randomly assigned to receive either SSC or modified open-sandwich restoration. One hundred and sixty restorations were placed and evaluated after 6, 12, 18, and 24 months using the Ryge criteria. Results. Comparable survival rates were observed for both SSC and modified open-sandwich restoration. With only four SSCs and six modified open-sandwich restorations failing over 24 months, the survival rates were high for both materials (2-year survival rate: 95.0% for SSCs and 92.5% for modified open-sandwich restorations). Significantly better gingival health (P < 0.05) was observed for the modified open-sandwich restorations compared with SSCs, as only one modified open-sandwich restoration was rated Charlie compared to 13 SSCs. No significant differences were observed between the two materials for marginal integrity, proximal contact, occlusion, or recurrent caries. Conclusion. The 2-year results indicated that the modified open-sandwich restoration is an appropriate alternative to SSC in extensive restorations, particularly where aesthetic considerations are important.