Comparison of Bonding Failure Rates of Fixed Lingual Mandibular Retainers in a French Sample Aged 11 or Older, Comparing Prior Enamel Sandblasting With Conventional Pumice Polishing
CONTORTHO
1 other identifier
interventional
88
1 country
1
Brief Summary
At the completion of orthodontic treatment, the position of the mandibular canines and incisors is being maintained on a routine basis by bonding a multi-braided wire retainer onto their lingual surfaces. One of the adverse events that might occur with time is the debonding of the wire from one or several lower anterior teeth . This event which can unfortunately get unnoticed by the patient can lead to unwanted tooth displacement. When the practionner detects such a debonding, he has to go through a laborious and lengthy procedure to rebond the wire. When on the other hand the patient notices himself such a debonding, he is to call in emergency his practitioner to get his retainer repaired. This leads to emergency visits that are susceptible to affect adversely his timetable. The prevalence of these bonding failures is estimated at 37% at 18 month follow-ups. It has been reported that with prior enamel sandblasting, bonding failure rate is reduced to 8% at 24 month follow-ups. However, no study has reported yet the debonding rate of lower fixed, comparing wires that have been bonded after prior enamel pumicing to those that were put in place after prior enamel sandblasting. The expected result of this trial is a significantly decrease in bonding failure rate of mandibular lingual retainer when enamel surfaces are initially sandblasted compared to the ones which are pumiced. This reduction would lower the risk of unwanted tooth movement of mandibular incisors and canines after orthodontic treatment and decrease the number of emergency appointments for the patient and the practitioner.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for not_applicable
Started Oct 2019
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
May 14, 2019
CompletedFirst Posted
Study publicly available on registry
May 17, 2019
CompletedStudy Start
First participant enrolled
October 8, 2019
CompletedPrimary Completion
Last participant's last visit for primary outcome
May 20, 2021
CompletedStudy Completion
Last participant's last visit for all outcomes
May 21, 2021
CompletedResults Posted
Study results publicly available
June 29, 2026
CompletedJune 29, 2026
June 1, 2026
1.6 years
May 14, 2019
November 17, 2025
June 3, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
Number of Participants With at Least One Bonding Failure at 18 Months
Participants presenting at least one debonding event of the fixed mandibular lingual retainer during the 18-month follow-up period. A retainer was considered failed if at least one bonded tooth became detached.
18 months after bonding of the fixed mandibular lingual retainer
Study Arms (2)
PUMICING GROUP
ACTIVE COMPARATORLingual surfaces of the lower incisors and canines are pumiced before bonding the lingual retainer. Teeth are being cleaned using a brush loaded with pumice and mounted on a low speed contra-angle.Teeth are then etched and the multi-braided retainer wire is being bonded with composite onto the lingual surfaces of the lower canines and incisors
SANDBLASTING GROUP
EXPERIMENTALEnamel is being initially prepared through sandblasting the lingual surfaces of the mandibular canines and incisors. Sandblasting is performed with the help of a MicroEtcher IIATM (Danville) which is projecting 50 μm Al2O3 particles onto the enamel surfaces. Teeth are subsequently etched and the retainer is then being bonded with composite onto the lingual surfaces of the mandibular incisors and canines.
Interventions
Lingual surfaces of the lower incisors and canines are pumiced before bonding the lingual retainer. Teeth are being cleaned using a brush loaded with pumice and mounted on a low speed contra-angle. Teeth are then etched and the multi-braided retainer wire is being bonded with composite onto the lingual surfaces of the lower canines and incisors.
Enamel is being initially prepared through sandblasting the lingual surfaces of the mandibular canines and incisors. Sandblasting is performed with the help of a MicroEtcher IIATM (Danville) which is projecting 50 μm Al2O3 particles onto the enamel surfaces. Teeth are subsequently etched and the retainer is then being bonded with composite onto the lingual surfaces of the mandibular incisors and canines.
Eligibility Criteria
You may qualify if:
- Minimum of 11 years of age
- At completion of fixed orthodontic therapy
- Presence of all 6 mandibular canines and incisors
You may not qualify if:
- Active decay
- Presence of dental restorations
- Tooth fracture
- Periodontal disease
- Structural anomalies affecting the lingual side of the mandibular incisors and canines
- Cleft lip and palate
- Cranio-facial syndrome
- Inability to obtain the patient informed consent
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Pôle de Médecine et Chirurgie Bucco-Dentaires
Strasbourg, Bas Rhin, 67000, France
Related Publications (1)
Kamm Q, Phonchareun E, Esquenet M, Rafflenbeul F, Severac F, Bolender Y. Comparison of bonding failure rates of mandibular retainers after 2 enamel preparations - sandblasting vs pumicing: An 18-month randomized controlled trial. Am J Orthod Dentofacial Orthop. 2025 Sep;168(3):262-272. doi: 10.1016/j.ajodo.2025.04.015.
PMID: 40885597RESULT
Results Point of Contact
- Title
- Quentin KAMM
- Organization
- Hôpitaux Universitaires de Strasbourg (HUS)/ Strasbourg University Hospital
Publication Agreements
- PI is Sponsor Employee
- Yes
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- INVESTIGATOR, OUTCOMES ASSESSOR
- Purpose
- SUPPORTIVE CARE
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
May 14, 2019
First Posted
May 17, 2019
Study Start
October 8, 2019
Primary Completion
May 20, 2021
Study Completion
May 21, 2021
Last Updated
June 29, 2026
Results First Posted
June 29, 2026
Record last verified: 2026-06