Stability, survival, and patient satisfaction with CAD/CAM versus conventional multistranded fixed retainers in orthodontic patients: a 6-month follow-up of a two-centre randomized controlled clinical trial

Arwa Gera, Helen Pullisaar, Paolo M Cattaneo, Shadi Gera, Vaska Vandevska-Radunovic, Marie A Cornelis, Arwa Gera, Helen Pullisaar, Paolo M Cattaneo, Shadi Gera, Vaska Vandevska-Radunovic, Marie A Cornelis

Abstract

Objectives: The primary aim of this two-arm parallel two-centre randomized controlled trial was to compare computer-aided design and computer-aided manufacturing (CAD/CAM) versus conventional multistranded fixed retainers (FRs) in terms of stability over 6 months. Secondary outcomes were failure rates and patient satisfaction.

Methods: Patients were randomized to CAD/CAM or conventional FRs in both arches, in 1:1 ratio and blocks of four. Allocation concealment was secured by using sequentially numbered envelopes. Patients were blinded. Retainers were bonded at the end of orthodontic treatment (T0), and patients were recalled after 1 (T1), 3 (T3), and 6 (T6) months. First-time retainer failures were recorded and digital impressions were taken. Arch widths and lengths, as well as Little's Irregularity Index (LII), were measured. Additionally, patients answered satisfaction questionnaires. Linear mixed models were applied for measurements and patient satisfaction. Survival analyses were estimated with Kaplan-Meier curves, along with Cox-regression modelling.

Results: One hundred and eighty-one patients were randomized (98 in Centre 1, and 83 in Centre 2): Ninety in the CAD/CAM group and 91 in the conventional group. Three subjects dropped out at baseline, as they did not attend any of the follow-up appointments.168 patients attended the T6 visit. There were no significant differences in arch dimensions between T0 and T6, whilst the LII was different only in the CAD/CAM group (mean difference: 0.2 mm; 95% confidence interval: 0.1 to 0.4; P < 0.001). Within 6 months, 39 upper retainers (19 out of 88 CAD/CAM and 20 out of 90 conventional retainers) and 52 lower retainers failed (26 out of 88 CAD/CAM and 26 out of 90 conventional retainers), with no significant difference between the survival of both types of retainers (hazard ratios conventional to CAD/CAM: upper arch: 0.99 [P =0.99], lower arch: 0.93 [P = 0.80]). There were no significant changes in patient satisfaction between the groups. No harms were observed.

Conclusions: There were no clinically significant differences in LII, arch widths and lengths between CAD/CAM and conventional retainers after 6 months. There was no difference in failures and in patient satisfaction between both types of FRs.

Registration: ClinicalTrials.gov NCT04389879.

© The Author(s) 2022. Published by Oxford University Press on behalf of the European Orthodontic Society.

Figures

Figure 1.
Figure 1.
(a) 0.014 × 0.014-inch rectangular Nitinol CAD/CAM generated fixed retainers (Memotain), with silicone transfer key on printed models. (b) Upper and lower Memotain retainers bonded canine-to-canine. (c) 0.0215-inch conventional six-stranded stainless-steel retainers, with silicone transfer key on printed models. (d) Upper and lower six-stranded stainless-steel retainers bonded canine-to-canine.
Figure 2.
Figure 2.
Arch width and length (mm). ICD, inter-canine distance; distance between the cusp tips of right and left permanent canines; IPD, inter-premolar distance; distance between the tip of the buccal cusp of the right and left first premolars; IMD, inter-molar distance; distance between the tip of the mesiobuccal cusp of the right and left first permanent molars; AL, arch length; the distance between the incisal edge of the most prominent central incisor to the frontal/coronal plane passing through the most posterior aspect of the first permanent molars. In case of abrasion of a cusp, the centre of the abrasion facet was used instead of the centre of the cusp.
Figure 3.
Figure 3.
CONSORT diagram showing the flow of patients through the trial.
Figure 4.
Figure 4.
Kaplan-Meier survival curves for the upper and lower arches according to CAD/CAM and Conventional FRs. CAD/CAM, computer-aided design and computer-aided manufacturing; FR, fixed retainers.
Figure 5.
Figure 5.
Distribution of bond failures per tooth in each group up to 6-month follow-up.
Figure 6.
Figure 6.
Patients’ satisfaction visual analogue scale (VAS) changes over time.

References

    1. Papagiannis, A., Koletsi, D., Halazonetis, D.J. and Sifakakis, I. (2021) Relapse 1 week after bracket removal: a 3D superimpositional analysis. European Journal of Orthodontics, 43, 128–135.
    1. Littlewood, S.J., Millett, D.T., Doubleday, B., Bearn, D.R. and Worthington, H.V. (2016) Retention procedures for stabilising tooth position after treatment with orthodontic braces. Cochrane Database of Systematic Reviews, 2016, CD002283.
    1. Wouters, C., Lamberts, T.A., Kuijpers-Jagtman, A.M. and Renkema, A.M. (2019) Development of a clinical practice guideline for orthodontic retention. Orthodontics & Craniofacial Research, 22, 69–80.
    1. Bearn, D.R. (1995) Bonded orthodontic retainers: a review. American Journal of Orthodontics and Dentofacial Orthopedics, 108, 207–213.
    1. Renkema, A.M., Sips, E.T., Bronkhorst, E. and Kuijpers-Jagtman, A.M. (2009) A survey on orthodontic retention procedures in The Netherlands. European Journal of Orthodontics, 31, 432–437.
    1. Padmos, J., Fudalej, P. and Renkema, A. (2018) Epidemiologic study of orthodontic retention procedures. American Journal of Orthodontics and Dentofacial Orthopedics, 153, 496–504.
    1. Vandevska-Radunovic, V., Espeland, L. and Stenvik, A. (2013) Retention: type, duration and need for common guidelines. A survey of Norwegian orthodontists. Orthodontics: The Art and Practice of Dentofacial Enhancement, 14, e110–e117. doi:10.11607/ortho.964
    1. Meade, M. J., Dreyer, C. W. (2019) A survey of retention and retainer practices of orthodontists in Australia. Australian Orthodontic Journal, 35, 174–183.
    1. Padmos, J., Mei, L., Wouters, C. and Renkema, A.M. (2019) Orthodontic retention procedures in New Zealand: a survey to benefit clinical practice guideline development. Journal of the World Federation of Orthodontists, 8, 24–30.
    1. Taner, T. and Aksu, M. (2012) A prospective clinical evaluation of mandibular lingual retainer survival. European Journal of Orthodontics, 34, 470–474. doi:10.1093/ejo/cjr038
    1. Al-Moghrabi, D., Pandis, N. and Fleming, P.S. (2016) The effects of fixed and removable orthodontic retainers: a systematic review. Progress in Orthodontics, 17, 24.
    1. Bondemark, L., Holm, A.K., Hansen, K., Axelsson, S., Mohlin, B., Brattstrom, V., Paulin, G. and Pietila, T. (2007) Long-term stability of orthodontic treatment and patient satisfaction. A systematic review. Angle Orthodontist, 77, 181–191.
    1. Booth, F.A., Edelman, J.M. and Proffit, W.R. (2008) Twenty-year follow-up of patients with permanently bonded mandibular canine-to-canine retainers. American Journal of Orthodontics and Dentofacial Orthopedics, 133, 70–76.
    1. Renkema, A.M., Renkema, A., Bronkhorst, E. and Katsaros, C. (2011) Long-term effectiveness of canine-to-canine bonded flexible spiral wire lingual retainers. American Journal of Orthodontics and Dentofacial Orthopedics, 139, 614–621.
    1. Cooke, M.E. and Sherriff, M. (2010) Debonding force and deformation of two multi-stranded lingual retainer wires bonded to incisor enamel: an in vitro study. European Journal of Orthodontics, 32, 741–746.
    1. Kravitz, N.D., Grauer, D., Schumacher, P. and Jo, Y.-m (2017) Memotain: a CAD/CAM nickel-titanium lingual retainer. American Journal of Orthodontics and Dentofacial Orthopedics, 151, 812–815.
    1. Shim, H., Foley, P., Bankhead, B. and Kim, K.B. (2022) Comparative assessment of relapse and failure between CAD/CAM stainless steel and standard stainless steel fixed retainers in orthodontic retention patients. Angle Orthodontist, 92, 87–94.
    1. Jost-Brinkmann, P.G., Cacciafesta, V. and Miethke, R.R. (1996) Computer-aided fabrication of bonded lingual retainers. Journal of Clinical Orthodontics, 30, 559–563.
    1. Wolf, M., Schumacher, P., Jäger, F., Wego, J., Fritz, U., Korbmacher-Steiner, H., Jäger, A. and Schauseil, M. (2015) Novel lingual retainer created using CAD/CAM technology: evaluation of its positioning accuracy. Journal of Orofacial Orthopedics, 76, 164–174.
    1. Artun, J. and Zachrisson, B. (1982) Improving the handling properties of a composite resin for direct bonding. American Journal of Orthodontics, 81, 269–276.
    1. Katsaros, C., Livas, C. and Renkema, A.-M. (2007) Unexpected complications of bonded mandibular lingual retainers. American Journal of Orthodontics and Dentofacial Orthopedics, 132, 838–841.
    1. Livas, C. and Delli, K. (2013) Subjective and objective perception of orthodontic treatment need: a systematic review. European Journal of Orthodontics, 35, 347–353.
    1. Alrawas, M.B., Kashoura, Y., Tosun, O. and Öz, U. (2021) Comparing the effects of CAD/CAM nickel-titanium lingual retainers on teeth stability and periodontal health with conventional fixed and removable retainers: a randomized clinical trial. Orthodontics & Craniofacial Research, 24, 241–250.
    1. Gelin, E., Seidel, L., Bruwier, A., Albert, A. and Charavet, C. (2020) Innovative customized CAD/CAM nickel-titanium lingual retainer versus standard stainless-steel lingual retainer: a randomized controlled trial. Korean Journal of Orthodontics, 50, 373–382.
    1. Kartal, Y., Kaya, B. and Polat-Özsoy, O. (2021) Comparative evaluation of periodontal effects and survival rates of Memotain and five-stranded bonded retainers: a prospective short-term study. Journal of Orofacial Orthopedics, 82, 32–41.
    1. Little, R.M. (1975) The irregularity index: a quantitative score of mandibular anterior alignment. American Journal of Orthodontics, 68, 554–563.
    1. Bjering, R., Sandvik, L., Midtbo, M. and Vandevska-Radunovic, V. (2017) Stability of anterior tooth alignment 10 years out of retention. Journal of Orofacial Orthopedics, 78, 275–283.
    1. Lindsey, J. K. (1999) Models for Repeated Measurements. 2 edn. Oxford University Press, OUP Catalogue,Oxford, UK.
    1. Shah, A.A. (2003) Postretention changes in mandibular crowding: a review of the literature. American Journal of Orthodontics and Dentofacial Orthopedics, 124, 298–308.
    1. Egli, F., Bovali, E., Kiliaridis, S. and Cornelis, M.A. (2017) Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: comparison of retainer failures and posttreatment stability. A 2-year follow-up of a single-center randomized controlled trial. American Journal of Orthodontics and Dentofacial Orthopedics, 151, 15–27.
    1. Forde, K., Storey, M., Littlewood, S.J., Scott, P., Luther, F. and Kang, J. (2017) Bonded versus vacuum-formed retainers: a randomized controlled trial. Part 1: stability, retainer survival, and patient satisfaction outcomes after 12 months. European Journal of Orthodontics, 40, 387–398.
    1. Pazera, P., Fudalej, P. and Katsaros, C. (2012) Severe complication of a bonded mandibular lingual retainer. American Journal of Orthodontics and Dentofacial Orthopedics, 142, 406–409.
    1. Shaughnessy, T.G., Proffit, W.R. and Samara, S.A. (2016) Inadvertent tooth movement with fixed lingual retainers. American Journal of Orthodontics and Dentofacial Orthopedics, 149, 277–286.
    1. Artun, J., Spadafora, A.T. and Shapiro, P.A. (1997) A 3-year follow-up study of various types of orthodontic canine-to-canine retainers. European Journal of Orthodontics, 19, 501–509.
    1. Bolla, E., Cozzani, M., Doldo, T. and Fontana, M. (2012) Failure evaluation after a 6-year retention period: a comparison between glass fiber-reinforced (GFR) and multistranded bonded retainers. International Orthodontics, 10, 16–28.
    1. Bovali, E., Kiliaridis, S. and Cornelis, M.A. (2014) Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: a single-center randomized controlled trial comparing placement time and failure over a 6-month period. American Journal of Orthodontics and Dentofacial Orthopedics, 146, 701–708.
    1. Stormann, I. and Ehmer, U. (2002) A prospective randomized study of different retainer types. Journal of Orofacial Orthopedics, 63, 42–50.
    1. Zachrisson, B. U. (2007) Long-term experience with direct-bonded retainers: update and clinical advice. Journal of clinical orthodontics: JCO, 41, 728–737; quiz 749
    1. Lumsden, K.W., Saidler, G. and McColl, J.H. (1999) Breakage incidence with direct-bonded lingual retainers. British Journal of Orthodontics, 26, 191–194.
    1. Nagani, N.I., Ahmed, I., Tanveer, F., Khursheed, H.M. and Farooqui, W.A. (2020) Clinical comparison of bond failure rate between two types of mandibular canine-canine bonded orthodontic retainers- a randomized clinical trial. BMC Oral Health, 20, 180.
    1. Wong, P. and Freer, T.J. (2005) Patients’ attitudes towards compliance with retainer wear. Australian Orthodontic Journal, 21, 45–53.
    1. Scribante, A., Sfondrini, M.F., Broggini, S., D’Allocco, M. and Gandini, P. (2011) Efficacy of ESTHETIC RETAINERS: clinical comparison between multistranded wires and direct-bond glass fiber-reinforced composite splints. International Journal of Dentistry, 2011, 548356.
    1. Bjering, R., Birkeland, K. and Vandevska-Radunovic, V. (2015) Anterior tooth alignment: a comparison of orthodontic retention regimens 5 years posttreatment. The Angle Orthodontist, 85, 353–359.

Source: PubMed

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