Comparison of survival time between two types of orthodontic fixed retainer: a prospective randomized clinical trial

Abstract

BackgroundThe aim of this prospective clinical study was to compare the mean durability and the failure rates of two types of orthodontic retainers.MethodsOrthodontic patients (142) aged between 14 and 28 years were recruited in this study. The polyethylene woven ribbon (Ribbond, Seattle, WA, USA) retainer was compared with a 0.0175-in flexible spiral wire (Respond, Ormco, Glendora, CA, USA) retainer. When treatment was completed, the retainers were bonded from canine to canine in the maxillary and the mandibular arches of the participants. In the follow-up visits, the patients were re-evaluated every 3 months over a period of 18 months. The time taken for the retainers to remain without any fracture was appraised. Kaplan-Meier analysis and the logrank test were employed to identify significant differences in the survival functions between the groups. The rates of the retainers' failure between the groups were analyzed using Chi-square test.ResultsIt was revealed that the mean survival of the flexible spiral wire retainer was 15.34 ± 0.47 and 15.60 ± 0.42 months in the maxillary and mandibular arches, respectively. The mean survival of the ribbon retainer was 13.95 ± 0.55 and 14.26 ± 0.57 months in the maxillary and mandibular arches, respectively. Ribbon retainers showed a failure rate of 50% in the maxillary and 42.6% in the mandibular arches. Flexible spiral retainers showed a failure rate of 36.5% in the maxillary and 37.8% in the mandibular arches. The differences were not statistically significant. Regarding the evaluation period, the differences had limited clinical significance.ConclusionThe mean survival time and the failure rates of the polyethylene woven ribbon retainer were comparable to the flexible spiral wire retainer during the 18 months after orthodontic treatment.

Retenedores fijos en ortodoncia. Revisión sistemática

“…The second generation did not dobleces terminales, ya que el espiral del alambre ofrecía buena retención; la desventaja de este diseño es que su diámetro (0.032 pulgadas) produce menos estabilidad. 9,22,23 En los últimos diez años se han utilizado alambres multitrenzados rígidos de mayor diámetro (0.032 pulgadas) cementados únicamente en caninos, y otro tipo de alambre multitrenzado más flexible generalmente de menor diámetro (0.017-0.021 pulgadas), cementado en cada diente de canino a canino. 13,19 Las ventajas de usar un alambre multitrenzado es que su superficie irregular incrementa la retención mecánica sin la necesidad de realizar dobleces retentivos, y la flexibilidad del alambre permite los movimientos fisiológicos de los dientes.…”

“…17,18 Con la introducción de la técnica adhesiva, 19 el retenedor lingual ha sido ampliamente usado para preservar los cambios obtenidos durante el tratamiento de ortodoncia en las últimas décadas. 9,12,20,21 Éste consiste en un alambre de cierta longitud adherido usualmente de canino a canino en su superficie lingual.…”

“…1,2,4,5,[7][8][9] In the absence of a retention phase, teeth tend to return to their initial position. To prevent recurrence, it is necessary to perform some form of retention.…”

“…17,18 With the introduction of the adhesive technique, 19 the lingual retainer has become widely used in recent decades to preserve the changes achieved during orthodontic treatment. 9,12,20,21 This consists of a wire of certain length usually bonded from canine to canine on the lingual surface. 12,19 Since its introduction in 1977, several modifications have been made to the wires used.…”

“…6,7,10,11 Many retention devices are currently used to keep the shape of the arch and to prevent recurrence. 1,2,4,7,9,10,[12][13][14] Designed in 1919, the Hawley plate is the most popular removable retainer. 15 In 1993, Sheridan et al introduced the Essix plates as a modern, aesthetic, comfortable, and inexpensive alternative to traditional retainers.…”