Finnish dentists' perceptions of the longevity of direct dental restorations

To evaluate Finnish dentists' perceptions of the longevity of direct dental restorations; to assess the possible impacts of dentists' characteristics on these perceptions; and to compare the present longevity estimates with those of recent European reports.

A questionnaire to 592 general practitioners, systematically sampled from the Finnish Dental Association's membership list, was posted in April 2004 and data collection was finished by the end of June. The question "In general, what is your estimate for the mean age of restoration in permanent teeth?" pointed restorations: Class II and MOD composites and amalgam in a posterior tooth and Class III composites in an incisor. Dentists' gender, main work, and year of graduation served as background information. Of the 339 (57%) respondents, only public and private dentists were included; 11 were excluded. Three studies fulfilled the inclusion criteria for recent reports on restoration longevity. Statistical evaluation was by one-way ANOVA, with p=0.05 as the level of significance.

The mean of the estimates for all types of composite was 9.0 years (SD 3.6; 95% CI 8.6-9.3) and 18.7 years for amalgam (SD 7.3; 95% CI 18.0-19.5). Male dentists gave longer estimates than female dentists for posterior composites, but shorter estimates for amalgam. Compared to public dentists, private dentists gave longer estimates for posterior composites. All estimates were longer than those reported in the recent literature.

Dentists' perceptions of posterior composite longevity are significantly longer among males than among females and among private than public sector dentists, and exceed the median longevity reported in recent studies.