New Zealand dental practitioners' experience of patient allergies to dental alloys used for prosthodontics.

UNLABELLED: The biocompatibility of metal alloys has generated much concern for practitioners and patients alike over recent years.

OBJECTIVES: To investigate dentists' experience of patient allergies to metal alloys used in prosthodontic restorations.

DESIGN: Cross-sectional survey of New Zealand practising general dentists.

METHODS: A random sample of 700 was taken from the New Zealand dental register. The questionnaire asked dentists whether any of their patients have encountered any allergic reactions to metal alloys. It also sought information on what alloys were being prescribed for use in different types of prosthodontic restorations.

RESULTS: A response rate of 71.4% was obtained (N = 476). Some 83 dentists (17.4%) reported having encountered suspected metal allergies in patients; of those, 70 had had the allergies confirmed with a biopsy. Of the entire sample, 327 dentists (72.2%) were aware of the metals used in their restorations, and 201 (44.8%) specified the alloys used in their restorations. For cast removable prosthodontic restorations (such as removable partial dentures), base metal alloys were the most preferred choice; for full cast crowns, high noble alloys were the most favoured; noble alloys were the most favoured for both porcelain-fused-to-metal crowns and fixed-bridge restorations.

CONCLUSION: As many as one in six general practising dentists have encountered allergic reactions to metal alloys in their patients. General practising dentists' awareness of the indications for the various metal alloys used in prosthodontic restorations should be raised, and biocompatibility issues should be clarified, so that dentists prescribe the optimum metal alloy for each type of restoration.