© Photo: F. Staxrud, DDS

Filling materials

Repair, expand or replace a composite filling?

There are no clear guidelines on when to repair or replace a defect composite filling. Studies based on student teaching in Britain and the United States showed that replacement was more common than repair, but that the indications of the various treatment options were quite similar (1).

Reasons for replacement were secondary caries, fracture of the filling and/or tooth structure and worn material, whereas repairs were made on fractured filling and material degradation (1). Three years after the repair the quality of the filling was as good as if the filling should have been replaced totally (2). A repair extends the life of the original filling (3) and will also often lead to saved tooth substance and lower patient cost.

Composite fillings of micro filler and hybrid type have very long life time that can be attributed to good physical properties and abrasion resistance. A number of studies conclude with an annual failure rate (AFR) of 1–3% for such composite fillings, which is on par with dental amalgam fillings (4).

Caries is the reason for the replacement of fillings in almost half of the cases, and there are about as many that fail due to fracture of the filling (5). These findings mean that for patients with low or no caries activity repairs should be the first choice if it is technically possible, paying attention to filling design (anatomy) to resist fracture.

Cusp fracture is not uncommon in association with a Class II filling. In the cases where the filling has adequate attachment and good quality, an expansion of the filling rather than total replacement would be beneficial to the patient.

F. Staxrud, DDS, and J. E. Dahl, Professor


  1. Setcos JC, Khosravi R, Wilson NH, Shen C, Yang M, Mjör IA. Repair or replacement of amalgam restorations: decisions at a USA and a UK dental school. Oper Dent. 2004; 29(4):392–7.
  2. Moncada G, Martin J, Fernández E, Hempel MC, Mjör IA, Gordan VV. Sealing, refurbishment and repair of Class I and Class II defective restorations: a three-year clinical trial. J Am Dent Assoc. 2009; 140(4):425–32. 
  3. Fernández EM, Martin JA, Angel PA, Mjör IA, Gordan VV, Moncada GA. Survival rate of sealed, refurbished and repaired defective restorations: 4-year follow-up. Braz Dent J. 2011; 22(2):134–9. 
  4. Demarco FF, Corrêa MB, Cenci MS, Moraes RR, Opdam NJ. Longevity of posterior composite restorations: not only a matter of materials. Dent Mater. 2012; 28(1):87–101.
  5. Opdam NJ, Bronkhorst EM, Loomans BA, Huysmans MC. 12-year survival of composite vs. amalgam restorations. J Dent Res. 2010; 89(10):1063–7.