Removal, replacement and placement of amalgam restorations by Ontario dentists in 2002

To determine the patterns of removal, replacement and placement of amalgam restorations by Ontario dentists.

A structured self-administered postal survey was sent to dentists randomly selected from the list of all dentists licensed to practise dentistry in Ontario. The questionnaire sought information on the numbers of 1-, 2-, 3- and > or = 4-surfaced amalgam restorations and core amalgam build-ups that each dentist removed, replaced and placed during a 7-day period.

A total of 878 (44%) of 1,994 dentists responded to the survey. Most dentists (82%) who returned completed questionnaires (n = 837) had removed, replaced or placed at least one amalgam restoration during the 7-day period. Most respondents (90%) were general practitioners; respondents practised for a mean of 45.7 weeks each year and had practised for a mean of 20.1 years. On average, each dentist removed 8.91 (standard deviation [SD] 17.32) amalgam restorations during the 7-day period. However, the mean number of new amalgam restorations placed was just 6.64 (SD 18.88): 2.99 (SD 8.74) new restorations in previously unrestored teeth and 3.65 (SD 11.40) replacements of amalgam restorations removed from previously restored teeth. For the year 2002, it was estimated that the 6,915 dentists registered to practise in Ontario had removed 2,855,178 (95% confidence interval [CI] 2,484,566-3,225,790) amalgam restorations. Overall, the dentists placed 2,112,800 (95% CI 1,682,307-2,543,292) amalgam restorations; 1,163,665 (95% CI 919,204-1,408,126) to replace amalgams in previously restored teeth and 949,135 (95% CI 763,103-1,135,166) as new amalgam restorations.

Removal of old amalgam restorations by Ontario dentists exceeds current levels of placement and replacement of amalgam restorations.