IADR Abstract Archives
20-Year Follow up of ‘Open Sandwich’ and Total-Etch Posterior Composite Restorations
Objectives: To compare clinical performance of resin composite posterior Class II restorations placed with either an etch-and-rinse adhesive or an open sandwich technique using glass-ionomer cement and to investigate proximal dissolution of GIC over time.
Methods: Data on Class II restorations placed by one dutch GDP between 1990-2016 were collected from patient files, including caries risk, tooth related variables (nr. Surfaces, tooth number, presence of endo) and applied materials. Before 2001, the GDP placed posterior composite restorations routinely using the open sandwich technique with glass-ionomer cement and composite. After 2001, he switched over to total-etch technique using etch-and-rinse 3-step adhesive when placing a Class II composite restoration.
Date of restoration placement and last check-up visit (=censoring date) were recorded. Replacement, repair, endodontic treatment and extraction were considered as failures. Date and reason for failures were recorded.
Kaplan Meier statistics were applied and Annual Failures Rates (AFR) were calculated. To investigate influence of variables on longevity of restorations, a multilevel Cox-Regression was conducted (p<0.05), with clustering of data for restorations within the same patient.
Results: 675 Class II restorations were placed in 91 patients (age 15-79 years; 40m, 51f). 491 (73%) were total-etch restorations (observation time 2-18 years), and 184 (27%) open sandwich restorations (observation time 19-29 years).
AFRs were after 15 years 2.9% for total etch restorations and 9.7% for open sandwich restorations. secondary caries was equally distributed among the groups. 27% of the failures in the open sandwich group were due to proximal dissolution of glass ionomer cement.
The Cox-regression showed a significant higher risk for failure for the open sandwich technique compared to total-etch class II composite restorations (HR=2.9; p<0.001)
Conclusions: On the long term, open sandwich restorations show inferior clinical performance compared to total-etch class II composite restorations. Proximal dissolution of GIC seems a clinical problem for open sandwich restorations
Methods: Data on Class II restorations placed by one dutch GDP between 1990-2016 were collected from patient files, including caries risk, tooth related variables (nr. Surfaces, tooth number, presence of endo) and applied materials. Before 2001, the GDP placed posterior composite restorations routinely using the open sandwich technique with glass-ionomer cement and composite. After 2001, he switched over to total-etch technique using etch-and-rinse 3-step adhesive when placing a Class II composite restoration.
Date of restoration placement and last check-up visit (=censoring date) were recorded. Replacement, repair, endodontic treatment and extraction were considered as failures. Date and reason for failures were recorded.
Kaplan Meier statistics were applied and Annual Failures Rates (AFR) were calculated. To investigate influence of variables on longevity of restorations, a multilevel Cox-Regression was conducted (p<0.05), with clustering of data for restorations within the same patient.
Results: 675 Class II restorations were placed in 91 patients (age 15-79 years; 40m, 51f). 491 (73%) were total-etch restorations (observation time 2-18 years), and 184 (27%) open sandwich restorations (observation time 19-29 years).
AFRs were after 15 years 2.9% for total etch restorations and 9.7% for open sandwich restorations. secondary caries was equally distributed among the groups. 27% of the failures in the open sandwich group were due to proximal dissolution of glass ionomer cement.
The Cox-regression showed a significant higher risk for failure for the open sandwich technique compared to total-etch class II composite restorations (HR=2.9; p<0.001)
Conclusions: On the long term, open sandwich restorations show inferior clinical performance compared to total-etch class II composite restorations. Proximal dissolution of GIC seems a clinical problem for open sandwich restorations