Faulty metal-based fillings – to repair or to replace?

Amalgam fillingDental fillings have a limited life span, and this research looks at whether it is better to repair or replace faulty or degraded fillings made of dental amalgam (a mix of various metals and mercury) in molar teeth. Traditionally, faulty fillings have been replaced, however this approach can lead to further loss of the tooth as the cavity is emptied and then refilled. Repairing the faulty filling is a different approach, which may be more cost effective and cause less pain and anxiety for the patient.What was the research?

A systematic review of the evidence to find out whether it is better to repair or replace amalgam fillings in the molar teeth towards the back of the mouth.

Who conducted the research?

The research was conducted by a team led by Mohammad O. Sharif from the University of Manchester, on behalf of the Cochrane Oral Health Group. Melanie Catleugh, Alison Merry, Martin Tickle, Stephen M. Dunne, Paul Brunton, Vishal R. Aggarwal and Lee Yee Chong were also on the team.

What did the evidence say?

Despite a thorough search of the literature, no randomised controlled trials were found for inclusion in this review.

How good was the evidence?

Currently there is no evidence to support repairing or replacing amalgam fillings for adults.

What are the implications for dentists and the general public?

In the absence of any high level reliable evidence, dentists should base their decisions on clinical experience, individual circumstances and in conjunction with patient’s preferences where appropriate. As dental amalgam is being phased out around the world, it is unlikely that there will be future clinical trials in this area.


Sharif MO, Merry A, Catleugh M, Tickle M, Brunton P, Dunne SM, Aggarwal VR, Chong LY. Replacement versus repair of defective restorations in adults: amalgam. Cochrane Database of Systematic Reviews 2014, Issue 2. Art. No.: CD005970. DOI: 10.1002/14651858.CD005970.pub3.