Condition category
Oral Health
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Bracket failure (bracket detachment from the tooth) hinders the smooth progress of orthodontic treatment. Thus, a bracket failure rate that is as low as possible is of utmost importance for the clinician as well as for the patient. Recently, a new adhesive system was introduced. This system reduces the steps during bracket placement. Thus, the aim of this study is to evaluate the clinical performance (i.e. bracket failure as well as chair time) of this newly introduced adhesive pre-coated bracket system (PS) compared with a conventional bracket system (CS).

Who can participate?
Patients undergoing orthodontic treatment without tooth extraction

What does the study involve?
Participants receive orthodontic treatment where the mouth is divided into four segments that are randomly assigned to either the PS or CS bracket system. Bracket failure is measured over 6 months.

What are the possible benefits and risks of participating?
The risks of this study are the same as the risks of any routine non-extraction orthodontic treatment. No extra risks are present. The study will give insight concerning the chair time, i.e. the amount of time a patient spends in the chair for treatment, of these systems. Chair time is of great importance, particularly during the COVID-19 pandemic. Furthermore, this study will provide data on whether or not this system (PS) is as reliable as CS.

Where is the study run from?
Ondokuz Mayıs University (Turkey)

When is the study starting and how long is it expected to run for?
June 2018 to June 2019

Who is funding the study?
Investigator initiated and funded

Who is the main contact?
Dr Selma Elekdag-Türk

Trial website

Contact information



Primary contact

Prof Selma Elekdag-Turk


Contact details

Ondokuz Mayıs University
Faculty of Dentistry
Department of Orthodontics
+90 (0)5446403424

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number

OMÜ KAEK 2018/416

Study information

Scientific title

Evaluation of the flash-free adhesive system for a 6-month period: a split-mouth trial


Study hypothesis

The aim of this study was the evaluation of the following parameters:
1. The comparison of the bond failure and survival rates of the APC FF Adhesive Coated Appliance System (3M Unitek) with an OC system (Transbond XT Light Cure Adhesive Paste; 3M Unitek) for a 6-month period.
2. Comparison of the bond failure and survival rates of the upper and lower arches.
3. Comparison of the bond failure and survival rates for incisor, canine and premolar teeth.
4. Comparison of bracket failure and survival rates with respect to gender.
5. Comparison of the ARI scores upon bracket failure.
6. Comparison of the chair time required for each bonding procedure.
The null hypothesis was that there would be no difference in the aforementioned parameters.

Ethics approval

Approved 13/09/2018, Research Ethics Committee at the University of Ondokuz Mayıs (Former Dental School Building, Ondokuz Mayıs University, 55200 Atakum/Samsun, Turkey; +90 (0)362 312 19 19/2782;, ref: OMÜ KAEK 2018/416

Study design

Single-center randomized study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a participant information sheet


Orthodontic malocclusion


Patients willing to participate in this study receive orthodontic treatment with a split-mouth design, i.e. the mouth is divided into four experimental segments that are randomly assigned to either the pre-coated bracket system (PS) or a conventional bracket system (CS). The observation period for his study is 6 months.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Bracket failure, i.e. bracket detachment from the tooth, is visually observed. Bracket failure can occur at any timepoint during the observation period. Bracket failure was recorded at the routine monthly controls of the patients.

Secondary outcome measures

Type of failure: the bracket may have detached from the tooth intact with adhesive or without adhesive. Furthermore, the bracket may have fractured. These types of failures can occur at any timepoint during the observation period. These types of failures were recorded at the routine monthly controls of the patients.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Willingness to participate in this research project
2. Fully erupted maxillary and mandibular teeth with intact buccal enamel
3. Angle Class I and mild Class II malocclusions
4. Non-extraction patients
5. Normal overbite (1-2 mm)
6. Absence of severe rotations. Severe rotations would have prevented bracket placement or correct bracket placement at the first appointment
7. Absence of pretreatment of teeth with any chemical agents
8. Good oral hygiene, i.e. no bleeding upon probing

Participant type


Age group




Target number of participants


Total final enrolment


Participant exclusion criteria

1. Patients with skeletal problems
2. Patients with missing teeth
3. Patients with systemic disease
4. Patients with a previous history of orthodontic treatment

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Ondokuz Mayıs University
Faculty of Dentistry Department of Orthodontics

Sponsor information


Ondokuz Mayıs University

Sponsor details

19 Mayıs Ünv.
+90 (0)3623121919

Sponsor type




Funder type


Funder name

Investigator initiated and funded

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Planned publication in a peer-reviewed journal. All additional documents are available upon request from Dr Selma Elekdağ-Türk. Furthermore, the study protocol and statistical analyses will be available upon the publication of this manuscript.

IPD sharing statement
The datasets generated during and/or analysed during the current study are/will be available upon request from Prof. Dr Tamer Türk (, and Prof. Dr Selma Elekdag-Türk (

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

07/10/2020: Trial's existence confirmed by Ondokuz Mayıs University.