A comprehensive survey of retention procedures in Australia and New Zealand.

OBJECTIVES: This survey aimed to identify consistencies in retention procedures.

METHODS: Three hundred Australian orthodontists and 70 New Zealand orthodontists were randomly selected for the study. A questionnaire gathered their views regarding the most commonly used retainers, wire types and sizes of bonded retainers, factors influencing the design of retainers, duration of regular retention, definition of permanent retention, percentage of cases that needed permanent retention, factors influencing the decision to use permanent retention, changes in retention protocols over the last five years, and reasons for such changes.

RESULTS: Upper invisible and lower canine-to-canine bonded retainers were the most commonly used retainers. Pretreatment tooth position was the major factor influencing the design of retainers, and most respondents preferred bonded retainers. The majority preferred multistrand stainless steel wire for bonded retainers. The most common wire size was 0.0175 inch. Orthodontists more commonly recommended a regular retention period of more than two years, and defined permanent retention as "lifetime". Orthodontists applied permanent retention to either a very high or very low percentage of their cases. A high percentage of respondents made changes to their retention protocols over the past five years. There was no relationship between factors influencing the design of retainers and the preferred type of retainer. There was no consensus on the major factor influencing the decision to use permanent retention.

CONCLUSIONS: Retention procedures are variable and dependent largely on personal preferences. There does not seem to be any consistent pattern in the application of retention methodologies.