Evaluation of the efficiency of three different types of bonded retainers used in orthodontics

Abstract

The bonded retainers are mainly used for the mandibular dental arch. This study aims to analyse the efficiency of three different types of fixed retainers, multistranded 0.0195-in wire, Australian wire and Starbond CoS laser sintering retainer, as well as the relapse rate for each type of retainer used over a period of two years. The sample consisted of 159 patients, of whom 55 patients (Group 1) had multistranded 0.0195-in wire, 53 patients (Group 2) Australian wire, and 51 patients (Group 3) laser-sintering retainers. 16 partial or complete detachments were recorded in the first year of the retention phase, of which 5 retainers from Group 1, 6 from Group 2 and 5 from Group 3, in the case of lasers-sintering retainers only total detachments were noticed, and 2 of the multistranded retainers suffered deformations. The results show that there are no statistically significant differences between the three types of retainers in the first year of retention period, but laser-sintering retainer had a statistically significant better evolution compared to multistranded retainer (p=0.018) after two years of retention. No statistically significant differences were found between the three types of retainers regarding the rate of relapse (10.9% for Group 1, 7.5% for Group 2 and 7.8% for Group 3). In the second year of the retention phase, the relapse rate did not present a statistically significant change from the first year, but it increased slightly in patients from Group 1 and it decreased slightly in patients from Group 3. No fixed retention system is perfect, everything has its drawbacks.