OrthodonticNCT07650630
Comparison Between Periodontal Effects of Fixed and Vacuum-Formed Retainers
A study testing Fixed retainer and vacuum retainer in people with Orthodontic and Retainer, run by Cairo University at 1 site in Egypt.
Trial summary
One of the most crucial aspects of orthodontic therapy is retention, which is required to prevent orthodontic relapse . There are two main types of retainers, removable retainer which depends on patient compliance to achieve proper results, and fixed retainer which can overcome the problem of patient compliance, but… Read more about this study
- Who is it for?
- Ages 12 years and older
- Conditions the study is for
- Orthodontic, Retainer, Periodontal Health
- What is being tested?
- Fixed retainer and vacuum retainer
- Type of treatment
- Pill or oral medicine, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 46 participants
- Where
- 1 siteEgypt
- Study dates
- 21 Nov 2025to 31 Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 12 years and older
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Minimal age of twelve years.
- Presence of all mandibular anterior teeth from canine to canine.
- Completion of orthodontic multi-bracket treatment with the requirement of retention of the mandibular anterior teeth.
- Periodontal screening index ≤ 2 [18].
- Participation in all study visits.
Who cannot join
- Systemic disease potentially affecting the study outcome.
- Conditions requiring antibiotic prophylaxis for clinical measurements that trigger transitory bacteremia.
- Pregnant females.
- Chronic use of medications affecting the study outcome.
- Patients with active periodontal disease
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Clinical Evaluation of Gingival and Periodontal Health of Lower Anterior Teeth With Fixed Retainer Versus Removable Retainer: A Randomized Clinical Trial.
One of the most crucial aspects of orthodontic therapy is retention, which is required to prevent orthodontic relapse . There are two main types of retainers, removable retainer which depends on patient compliance to achieve proper results, and fixed retainer which can overcome the problem of patient compliance, but with using it there is higher risk of plaque accumulation and the process of brushing teeth becomes more complex. However, it is not known whether this necessarily leads to worsening of periodontal outcomes . The increasing use of permanent retainers and their requirement for continuous wear highlight the importance of evaluating their impact on the periodontal health but there is conflicting data available right now on how orthodontic retainers affect periodontal diseases
Read the detailed description
The purpose of this research is to compare the effect between fixed and removable retainer on periodontium as the current evidence on how these appliances affect periodontal health is still lacking significantly Orthodontic treatment plays an important role in enhancing the function, esthetics and overall well-being of patients. One of the most important elements of treatment is the retention phase. There are two main types of retainers that can be used in the retention phase either fixed or removable.
At first banded fixed appliances were used as retainers , then in 1919 Hawly introduced removable retainers , then in 1973 Kneirim RW. introduced the first bonded retainer as enamel etching and modern adhesive systems facilitated the use of bonded retention .
The most widely used removable retainer is the Hawley appliance, which is made of wire and acrylic resin.
In 1971 Ponitz introduced fiber reinforced retainer which is less expensive, with better esthetics and easy to clean but it is not dimensionally stable and more prone to wearing.
The duration of the retention phase frequently exceeds that of the active treatment. In many cases, orthodontists even propose lifetime retention.
Removable retainers depend greatly on patient compliance so fixed compliance-free retainers were introduced but they cause more plaque accumulation and make the process of brushing teeth more complex, also there is conflicting data about their effect on periodontal health Artun was one of the first orthodontists to investigate the periodontal effect of fixed retainers. He found out that more plaque accumulation occurred with fixed retainers, but he suggested that plaque and calculus accumulation gingival to the retainer wire might not cause serious damage to the periodontium According to the most recent Cochrane review concerning this matter, most of the studies found no difference in periodontal measurements between the two types of retainers but one study found that the lower fixed retainer group had considerably more periodontal pocketing and bleeding on probing than the full-time lower removable retainer . Nevertheless, it is important to exercise caution when interpreting this periodontal pocketing outcome because the two groups were not similar at debonding, with four times as many participants in the fixed retainer group
The most recent systematic reviews also concluded that the available evidence on this topic is inconclusive and that more research is needed which would help in choosing the suitable type of retainer for each patient as there are no specific guidelines for choosing one type of retainer over the other for each patient. But they concluded that fixed retainers are compatible with periodontal health, or at least not related to severe detrimental effects on the periodontium.
It must also be taken in consideration several factors when interpreting the results of effect of fixed retainers on periodontal health like Hawthrone effect, limited follow up period and selection bias as most studies select people with good periodontal health .
The concept of periodontal health was derived from Chapple et al. and is basically defined as having no clinical loss of attachment, limited bleeding on probing (< 10%), and no significantly elevated probing depths (≤ 3 mm)
- Conditions
- Orthodontic, Retainer, Periodontal Health
- Being tested
- Fixed retainer, vacuum retainer
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fixed retainerDevice
Patients are given oral hygiene instructions during retention period , frequent follow up visits with patients
vacuum retainerDevice
Patients are given oral hygiene instructions during retention period , frequent follow up visits with the patients
| Study group | Role | What they receive |
|---|---|---|
| intervention group ( fixed retainer group) | Active comparator | * At first, medical and dental histories will be taken from the patients then extra- and intra-oral examinations will follow.
* Brackets are removed using a plier at the end of active orthodontic treatment.
* Excess adhesive material is removed using finishing stones and rubber polishing kit.
* Polishing the teeth before placement of retainer. For the fixed retainer group, it will be fabricated from a stainless-steel alloy and applied to each lingual tooth surface from one mandibular canine to the contralateral canine.
The patients' teeth surfaces will then be prepared using 37% phosphoric acid etchant gel for 30 seconds, rinsed and dried with oil-free compressed air for 10 seconds. After drying the enamel surfaces, a bonding agent will be applied using a micro-brush, spread using oil-free compressed air followed by the application of the adhesive material and placement of the fixed retainer. After light curing excess adhesive material will be removed. Receives: Device: Fixed retainer |
| control group ( vacuum retainer group) | Active comparator | At first, medical and dental histories will be taken from the patients then extra- and intra-oral examinations will follow.
* Brackets are removed using a plier at the end of active orthodontic treatment.
* Excess adhesive material is removed using finishing stones and rubber polishing kit.
* Polishing the teeth before placement of retainer.
For the removable retainer group the mandibular removable retainers will be fabricated using thick thermoplastic vacuum-formed sheets, patients will be instructed to wear them full- time. Receives: Device: vacuum retainer |
What is being measured
The primary outcome is the main question the study is designed to answer.
Probing depth
Assessment of periodontal health using Periodontal probing depth Probing depth is measured in mms using periodontal probe, in a healthy periodontium pocket typically measures between 1 to 3 millimeters in depth
Measured: immediately after debonding and after 6 months
Bleeding on probing
Bleeding on probing is a 4 point scale Score 0: No bleeding No bleeding when you probe the gingival sulcus/pocket Score 1: Bleeding on probing Bleeding occurs after probing, usually within 10-30 seconds ,Mild bleeding at the gingival margin Score 2: Bleeding + profuse Bleeding is immediate, profuse, and often fills the sulcus, Or bleeding flows from the sulcus Score 3: Spontaneous bleeding, Bleeding occurs without any probing Seen before you even touch the tissue
Measured: immediately after debonding and after 6 months
gingival recession
Loss of clinical attachment level is measured as the distance in millimeters between the bottom of the pocket and the cementoenamel junction. Based on the extent of attachment loss, it can be categorized as light (1-2 mm), moderate (3-4 mm), or severe (5 mm or more) loss of clinical attachment.
Measured: immediately after debonding and after 6 months
Gingival index
Gingival index is a 4-point scale in which scale 0 is healthy periodontium and scale 3 is severe inflammation.
Measured: immediately after debonding and after 6 months
plaque index
Plaque index is a 4-point scale in which scale 0 indicates the absence of plaque at the free gingival margin after drying, and scale 3 represents an abundance of soft matter within the gingival pocket and/or on the gingival margin and adjacent tooth surface, including the interdental area
Measured: immediately after debonding and after 6 months
Secondary outcomes (1)
patient satisfaction
Assessment of patient satisfaction using questionnaire.
Measured: After 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jun 2026
- Study start21 Nov 2025
- Primary completion30 Jun 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for OrthodonticStudies of the same condition, open and under way.
- More trials run by Cairo UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Investigator, Outcomes assessor
- Enrolment
- 46 participants (actual)
Sponsor and investigators
- Lead sponsor
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Toka Mustafa Saad Mohamed, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07650630
- Sponsor's protocol ID
- ??1125
- Status last verified
- Jun 2026
- First submitted
- 9 Jun 2026
- Last updated
- 16 Jun 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 16 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clinical Evaluation of Gingival and Periodontal Health of Lower Anterior Teeth With Fixed Retainer Versus Removable Retainer: A Randomized Clinical Trial.
- ClinicalTrials.gov ID
- NCT07650630
- Acronym / sponsor ID
- ??1125
- Conditions
- Orthodontic, Retainer, Periodontal Health
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 46 participants (actual)
- Lead sponsor
- Cairo UniversityUniversity, hospital or other
- Study start
- 21 Nov 2025 (actual)
- Primary completion
- 30 Jun 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 16 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
One of the most crucial aspects of orthodontic therapy is retention, which is required to prevent orthodontic relapse . There are two main types of retainers, removable retainer which depends on patient compliance to achieve proper results, and fixed retainer which can overcome the problem of patient compliance, but with using it there is higher risk of plaque accumulation and the process of brushing teeth becomes more complex. However, it is not known whether this necessarily leads to worsening of periodontal outcomes . The increasing use of permanent retainers and their requirement for continuous wear highlight the importance of evaluating their impact on the periodontal health but there is conflicting data available right now on how orthodontic retainers affect periodontal diseases
Detailed description
The purpose of this research is to compare the effect between fixed and removable retainer on periodontium as the current evidence on how these appliances affect periodontal health is still lacking significantly Orthodontic treatment plays an important role in enhancing the function, esthetics and overall well-being of patients. One of the most important elements of treatment is the retention phase. There are two main types of retainers that can be used in the retention phase either fixed or removable.
At first banded fixed appliances were used as retainers , then in 1919 Hawly introduced removable retainers , then in 1973 Kneirim RW. introduced the first bonded retainer as enamel etching and modern adhesive systems facilitated the use of bonded retention .
The most widely used removable retainer is the Hawley appliance, which is made of wire and acrylic resin.
In 1971 Ponitz introduced fiber reinforced retainer which is less expensive, with better esthetics and easy to clean but it is not dimensionally stable and more prone to wearing.
The duration of the retention phase frequently exceeds that of the active treatment. In many cases, orthodontists even propose lifetime retention.
Removable retainers depend greatly on patient compliance so fixed compliance-free retainers were introduced but they cause more plaque accumulation and make the process of brushing teeth more complex, also there is conflicting data about their effect on periodontal health Artun was one of the first orthodontists to investigate the periodontal effect of fixed retainers. He found out that more plaque accumulation occurred with fixed retainers, but he suggested that plaque and calculus accumulation gingival to the retainer wire might not cause serious damage to the periodontium According to the most recent Cochrane review concerning this matter, most of the studies found no difference in periodontal measurements between the two types of retainers but one study found that the lower fixed retainer group had considerably more periodontal pocketing and bleeding on probing than the full-time lower removable retainer . Nevertheless, it is important to exercise caution when interpreting this periodontal pocketing outcome because the two groups were not similar at debonding, with four times as many participants in the fixed retainer group
The most recent systematic reviews also concluded that the available evidence on this topic is inconclusive and that more research is needed which would help in choosing the suitable type of retainer for each patient as there are no specific guidelines for choosing one type of retainer over the other for each patient. But they concluded that fixed retainers are compatible with periodontal health, or at least not related to severe detrimental effects on the periodontium.
It must also be taken in consideration several factors when interpreting the results of effect of fixed retainers on periodontal health like Hawthrone effect, limited follow up period and selection bias as most studies select people with good periodontal health .
The concept of periodontal health was derived from Chapple et al. and is basically defined as having no clinical loss of attachment, limited bleeding on probing (< 10%), and no significantly elevated probing depths (≤ 3 mm)
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| intervention group ( fixed retainer group) | Active comparator | Device: Fixed retainer* At first, medical and dental histories will be taken from the patients then extra- and intra-oral examinations will follow. * Brackets are removed using a plier at the end of active orthodontic treatment. * Excess adhesive material is removed using finishing stones and rubber polishing kit. * Polishing the teeth before placement of retainer. For the fixed retainer group, it will be fabricated from a stainless-steel alloy and applied to each lingual tooth surface from one mandibular canine to the contralateral canine. The patients' teeth surfaces will then be prepared using 37% phosphoric acid etchant gel for 30 seconds, rinsed and dried with oil-free compressed air for 10 seconds. After drying the enamel surfaces, a bonding agent will be applied using a micro-brush, spread using oil-free compressed air followed by the application of the adhesive material and placement of the fixed retainer. After light curing excess adhesive material will be removed. |
| control group ( vacuum retainer group) | Active comparator | Device: vacuum retainerAt first, medical and dental histories will be taken from the patients then extra- and intra-oral examinations will follow. * Brackets are removed using a plier at the end of active orthodontic treatment. * Excess adhesive material is removed using finishing stones and rubber polishing kit. * Polishing the teeth before placement of retainer. For the removable retainer group the mandibular removable retainers will be fabricated using thick thermoplastic vacuum-formed sheets, patients will be instructed to wear them full- time. |
Who may qualify
- Ages
- 12 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (5 listed)
- Minimal age of twelve years.
- Presence of all mandibular anterior teeth from canine to canine.
- Completion of orthodontic multi-bracket treatment with the requirement of retention of the mandibular anterior teeth.
- Periodontal screening index ≤ 2 [18].
- Participation in all study visits.
Key exclusion criteria (5 listed)
- Systemic disease potentially affecting the study outcome.
- Conditions requiring antibiotic prophylaxis for clinical measurements that trigger transitory bacteremia.
- Pregnant females.
- Chronic use of medications affecting the study outcome.
- Patients with active periodontal disease
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fixed retainerPatients are given oral hygiene instructions during retention period , frequent follow up visits with patients | Device | intervention group ( fixed retainer group) |
| vacuum retainerPatients are given oral hygiene instructions during retention period , frequent follow up visits with the patients | Device | control group ( vacuum retainer group) |
Primary outcome
Probing depth
Time frame: immediately after debonding and after 6 months
Assessment of periodontal health using Periodontal probing depth Probing depth is measured in mms using periodontal probe, in a healthy periodontium pocket typically measures between 1 to 3 millimeters in depth
Bleeding on probing
Time frame: immediately after debonding and after 6 months
Bleeding on probing is a 4 point scale Score 0: No bleeding No bleeding when you probe the gingival sulcus/pocket Score 1: Bleeding on probing Bleeding occurs after probing, usually within 10-30 seconds ,Mild bleeding at the gingival margin Score 2: Bleeding + profuse Bleeding is immediate, profuse, and often fills the sulcus, Or bleeding flows from the sulcus Score 3: Spontaneous bleeding, Bleeding occurs without any probing Seen before you even touch the tissue
gingival recession
Time frame: immediately after debonding and after 6 months
Loss of clinical attachment level is measured as the distance in millimeters between the bottom of the pocket and the cementoenamel junction. Based on the extent of attachment loss, it can be categorized as light (1-2 mm), moderate (3-4 mm), or severe (5 mm or more) loss of clinical attachment.
Gingival index
Time frame: immediately after debonding and after 6 months
Gingival index is a 4-point scale in which scale 0 is healthy periodontium and scale 3 is severe inflammation.
plaque index
Time frame: immediately after debonding and after 6 months
Plaque index is a 4-point scale in which scale 0 indicates the absence of plaque at the free gingival margin after drying, and scale 3 represents an abundance of soft matter within the gingival pocket and/or on the gingival margin and adjacent tooth surface, including the interdental area
1 secondary outcome
patient satisfaction
Time frame: After 6 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Jun 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Fixed retainer and vacuum retainer in people with Orthodontic and Retainer, run by Cairo University at 1 site in Egypt.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 16 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Egypt. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Probing depth (time frame: immediately after debonding and after 6 months). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Jun 2026.