Hygiene status associated with different types of bonded, orthodontic canine-to-canine retainers. A clinical trial

The present study was performed to test whether bonded, orthodontic canine-to-canine retainers made of spiral wire tended to accumulate more plaque than retainers made of plain wire, and whether the presence of such retainers caused any damage to the teeth involved. 44 patients were classified in eight strata according to age, gender and gingival status. From each stratum, the patients were randomly divided into 4 groups, each of which received either retainers made of thick plain wire bonded only to the canines, thick twisted wired bonded only to the canines, thin twisted wire bonded to each tooth or removable retainers. Accumulation of plaque and calculus along the gingival margin and gingival inflammation were scored in lingual areas from canine to canine at time of fixed appliance removal and again 4 months after retainer insertion. In addition, accumulation of plaque and calculus and development of caries along the retainer wires were scored after 4 months. The results revealed no differences between the groups for any of the variables. No differences in accumulation of plaque was found between baseline and follow-up examinations. Gingival bleeding was scored less frequently after 4 months in retention than at time of debonding.