Class II MalocclusionNCT05418413

The Use of an Esthetic Twin Block for Patients With Mandibular Retrusion

A study testing CTB and ETB in people with Class II Malocclusion, run by Damascus University at 1 site in Syria.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Trial summary

This experimental study will evaluate the effect of an esthetic Twin-block appliance on the correction of class II malocclusion compared with the traditional Twin-block appliance. The study sample will consist of 50 patients with class II malocclusion. Read more about this study

Who is it for?: Ages 11 to 14 years
Conditions the study is for: Class II Malocclusion
What is being tested?: CTB and ETB
Type of treatment: Medical device
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 50 participants
Where: 1 siteSyria
Study dates: 28 Dec 2021to 28 Feb 2023
Phase: Interventional
Are there results?: None posted in the registry

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 11 to 14 years
All sexes
No healthy volunteers
Child

Who may be able to join

Angle class II malocclusion because of mandibular retrognathia
O.J > 5 , SNB < 78
Patient during growth spurt
Normal or horizontal growth pattern Björk > 402

Who cannot join

TMJ disorders
Poor oral hygiene
Previous orthodontic treatment.
Patients with syndromes, clefts, or craniofacial abnormalities.
Reason of contraindication of functional treatment

Trial locations and contacts

1 site in 1 country.

Syria1 site

University of Damascus
Damascus

Other trials in Syria

About this study

Official title: Dentoskeletal Changes Resulting From Treatment of Skeletal Class II With an Esthetic Twin Block Appliance.

This experimental study will evaluate the effect of an esthetic Twin-block appliance on the correction of class II malocclusion compared with the traditional Twin-block appliance.

The study sample will consist of 50 patients with class II malocclusion. The sample will be allocated randomly into two groups: the control group and the experimental group.

The traditional Twin-block appliance will be applied for the control group patients, while the esthetic Twin-block appliance will be applied for the experimental group patients. The dentoskeletal, soft tissue changes and esthetic and functional efficacy occurring after functional treatment will be assessed using cephalometric radiographs and profile photographs, pre and post-treatment, and a questionnaire. Changes for each group will be evaluated individually, and the two groups will be compared.

Read the detailed description

Class II malocclusion is one of the most frequent orthodontic problems, and most class II malocclusion cases are the result of mandibular deficiency. Twin block (TB) is one of the most popular functional appliances to treat this condition. Despite excellent treatment results with TB, its acceptance and compliance may be hampered by its wiry structure and appearance. Furthermore, it has a side effect of causing the proclination of lower incisors, which reduces skeletal change. Various modifications were proposed to reduce lower incisors proclination but had no significant effect. Patient cooperation is one of the most important factors for successful functional appliance treatment, and it depends upon comfort and esthetic acceptability, which ensures good patient compliance. so, in order to enhance the esthetic appearance and overcome the disadvantages of a conventional Twin-Block (CTB), a novel esthetic Twin-Block (ETB) was fabricated from a specific material using a pressure molding device and acrylic bite blocks. There is only one study that evaluated this appliance which is a pilot study that compared the treatment effects of the (ETB) and (CTB) in the treatment of Class II malocclusions. However, this study has a lot of limitations, making it difficult to evaluate this appliance's efficiency accurately. The aim of this study is to study the dento-skeletal, soft tissue changes, and esthetic and functional efficacy that result from treatment by this appliance (ETB) and to compare them to the changes in the matched group will be treated with (CTB), by studying the cephalometric radiographs, profile photographs, and a questionnaire.

Conditions: Class II Malocclusion
Being tested: CTB, ETB
Keywords: Class II, Twin Block, Functional Therapy
Medical subject headings: Overbite

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

CTBDevice
conventional Twin-block (CTB) will be comprised of maxillary and mandibular removable appliances having the labial bows, adam's clasps, and with no incisal capping.
ETBDevice
will be comprised of maxillary and mandibular removable 1.5-mm biocryl sheet will be adapted separately on maxillary and mandibular casts with help of vacuum machine, and Acrylic bite blocks with the inclined plane will be fabricated on biocryl sheets sim

Study groups in NCT05418413
Study group	Role	What they receive
Conventional Twin-block appliance	Active comparator	The patients in this control group will be treated using the conventional Twin-block appliance (CTB). Receives: Device: CTB
Esthetic Twin-block appliance	Experimental	the patients in this experimental group will be treated using the esthetic Twin-block appliance (ETB). Receives: Device: ETB

What is being measured

The primary outcome is the main question the study is designed to answer.

Dentoskeletal mandible changes as measured by tomographic
changes of the mandible before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs
Measured: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1).
Lower incisor angle changes
Lower incisor angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
Measured: Changes will be evaluated before treatment and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
ANB angle changes
ANB angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
Measured: Changes will be evaluated before treatment and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)

Secondary outcomes (9)

Dentoskeletal maxilla changes as measured by tomographic superimposition of the cranial base
changes of the maxilla before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
Measured: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
SNA angle changes
SNA angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
Measured: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
SNB angle changes
SNB angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
Measured: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1).
Soft tissue changes
Soft tissue changes before and after treatment will be assessed and compared with those of the control group (Facial convexity angle, Nasolabial angle, Z-Merrifield angle, …etc) using profile photography.
Measured: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
The duration of functional treatment
The duration of the functional treatment will be measured and compared between groups.
Measured: After obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months
Levels of pain
The level of pain will be assessed and compared with those of the control group using a questionnaire with a Visual Analog Scale (VAS). The VAS is a 10-cm horizontal line with two focal points at its beginning and end (0: there is no pain - 10: the worst pain).
Measured: A questionnaire will be given to the patients five times during treatment; after 1 week, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Levels of discomfort
The level of discomfort will be assessed and compared with those of the control group using a questionnaire with a Visual Analog Scale (VAS). The VAS is a 10-cm horizontal line with two focal points at its beginning and end (0: there is no discomfort - 10: the worst discomfort).
Measured: A questionnaire will be given to the patients four times during treatment; after 1day, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Levels of acceptance
The level of acceptance will be assessed and compared with those of the control group using a questionnaire with a Visual Analog Scale (VAS). The VAS is a 10-cm horizontal line with two focal points at its beginning and end (0: no acceptance - 10: the best acceptance).
Measured: A questionnaire will be given to the patients four times during treatment; after 1day, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Number of broken appliances
The number of broken will be counted and compared with those of the control group .
Measured: During the treatment time which will take approximately 8 months.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

28 Dec 202128 Feb 2023

First posted14 Jun 2022
Study start28 Dec 2021
Primary completion30 Sep 2022
Study completion28 Feb 2023

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (7)Papers the sponsor has linked to this study.
Other trials for Class II MalocclusionStudies of the same condition, open and under way.
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: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind
Who is masked: Outcomes assessor
Enrolment: 50 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT05418413
Sponsor's protocol ID: UDDS-Ortho-12-2022
Status last verified: Apr 2023
First submitted: 10 Jun 2022
Last updated: 7 Apr 2023
Results posted: No
Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: No

Publications

Sidlauskas A. Clinical effectiveness of the Twin block appliance in the treatment of Class II Division 1 malocclusion. Stomatologija. 2005;7(1):7-10.
PubMed 16254470
Tripathi T, Singh N, Rai P, Gupta P. Comparison of Dentoskeletal Changes, Esthetic, and Functional Efficacy of Conventional and Novel Esthetic Twin Block Appliances among Class II Growing Patients: A Pilot Study. Turk J Orthod. 2020 Jun 1;33(2):77-84. doi: 10.5152/TurkJOrthod.2020.19030. eCollection 2020 Jun.
PubMed 32637187
Baccetti T, Franchi L, Toth LR, McNamara JA Jr. Treatment timing for Twin-block therapy. Am J Orthod Dentofacial Orthop. 2000 Aug;118(2):159-70. doi: 10.1067/mod.2000.105571.
PubMed 10935956
Shahamfar M, Atashi MHA, Azima N. Soft Tissue Esthetic Changes Following a Modified Twin Block Appliance Therapy: A Prospective Study. Int J Clin Pediatr Dent. 2020 May-Jun;13(3):255-260. doi: 10.5005/jp-journals-10005-1759.
PubMed 32904097
van der Plas MC, Janssen KI, Pandis N, Livas C. Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination. Angle Orthod. 2017 Jul;87(4):513-518. doi: 10.2319/102916-779.1. Epub 2017 Jan 27.
PubMed 28128634
Alsilq MN, Youssef M. Soft tissue effects of aesthetic and conventional twin block appliances in the treatment of skeletal class II malocclusion: a randomized controlled trial. Sci Rep. 2025 Oct 28;15(1):37627. doi: 10.1038/s41598-025-21538-w.
PubMed 41152368
Alsilq MN, Youssef M. Dentoskeletal effects of aesthetic and conventional twin block appliances in the treatment of skeletal class II malocclusion: a randomized controlled trial. Sci Rep. 2025 Jan 13;15(1):1879. doi: 10.1038/s41598-025-86219-0.
PubMed 39805909

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

Enrolling by invitation
Discision as Acceleration Method in Canine Retraction in Orthodontics With Aligner and Fixed Appliances in Young Adults a Split Mouth Study
Bimaxillary Protrusion, Class II Div 1 Malocclusion
Recruiting
Maxillary Arch Distalization With Infrazygomatic Crest Miniscrews for Class II Malocclusion
Class II Malocclusion
Recruiting
Comparing 3D-Printed and Milled Titanium Plates in Jaw Surgery (Le Fort I): Accuracy and Operative Time
Malocclusion, Angle Class II, Malocclusion, Angle Class III
Recruiting
Treatment of Mild Class II Malocclusion in Adult Patients With Clear Aligners Versus Fixed Multibracket Therapy
Malocclusion, Class II Malocclusion
Recruiting
Patient-Reported Outcomes for Different Orthodontic Thermoplastics Used in Clear Aligners
Malocclusion of Anterior Teeth, Malocclusion in Children

All Class II Malocclusion trials

Study at a glance

From the registry record, last updated by the sponsor on 7 Apr 2023. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Dentoskeletal Changes Resulting From Treatment of Skeletal Class II With an Esthetic Twin Block Appliance.
ClinicalTrials.gov ID: NCT05418413
Acronym / sponsor ID: UDDS-Ortho-12-2022
Conditions: Class II Malocclusion
Keywords: Class II, Twin Block, Functional Therapy
Study type: Interventional
Recruitment status: Completed
Enrolment: 50 participants (actual)
Lead sponsor: Damascus UniversityUniversity, hospital or other
Study start: 28 Dec 2021 (actual)
Primary completion: 30 Sep 2022 (actual)
Study completion: 28 Feb 2023 (actual)
First posted: 14 Jun 2022 (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.

This experimental study will evaluate the effect of an esthetic Twin-block appliance on the correction of class II malocclusion compared with the traditional Twin-block appliance.

The study sample will consist of 50 patients with class II malocclusion. The sample will be allocated randomly into two groups: the control group and the experimental group.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind (outcomes assessor)
Number of arms: 2

Arm	Type	Receives
Conventional Twin-block appliance	Active comparator	Device: CTBThe patients in this control group will be treated using the conventional Twin-block appliance (CTB).
Esthetic Twin-block appliance	Experimental	Device: ETBthe patients in this experimental group will be treated using the esthetic Twin-block appliance (ETB).

Who may qualify

Ages: 11 to 14 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Child

Key inclusion criteria (4 listed)

Angle class II malocclusion because of mandibular retrognathia
O.J > 5 , SNB < 78
Patient during growth spurt
Normal or horizontal growth pattern Björk > 402

Key exclusion criteria (5 listed)

TMJ disorders
Poor oral hygiene
Previous orthodontic treatment.
Patients with syndromes, clefts, or craniofacial abnormalities.
Reason of contraindication of functional treatment

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
CTBconventional Twin-block (CTB) will be comprised of maxillary and mandibular removable appliances having the labial bows, adam's clasps, and with no incisal capping.	Device	Conventional Twin-block appliance
ETBwill be comprised of maxillary and mandibular removable 1.5-mm biocryl sheet will be adapted separately on maxillary and mandibular casts with help of vacuum machine, and Acrylic bite blocks with the inclined plane will be fabricated on biocryl sheets sim	Device	Esthetic Twin-block appliance

Primary outcome

Dentoskeletal mandible changes as measured by tomographic
Time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1).
changes of the mandible before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs
Lower incisor angle changes
Time frame: Changes will be evaluated before treatment and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
Lower incisor angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.
ANB angle changes
Time frame: Changes will be evaluated before treatment and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
ANB angle changes before and after treatment will be assessed and compared with those of the control group using lateral cephalometric radiographs.

9 secondary outcomes

Dentoskeletal maxilla changes as measured by tomographic superimposition of the cranial base
Time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
SNA angle changes
Time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
SNB angle changes
Time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1).
Soft tissue changes
Time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1)
The duration of functional treatment
Time frame: After obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months
Levels of pain
Time frame: A questionnaire will be given to the patients five times during treatment; after 1 week, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Levels of discomfort
Time frame: A questionnaire will be given to the patients four times during treatment; after 1day, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Levels of acceptance
Time frame: A questionnaire will be given to the patients four times during treatment; after 1day, after 1 week, after 6 weeks, after 3 months and at the end of the application of the appliance.
Number of broken appliances
Time frame: During the treatment time which will take approximately 8 months.

Results and safety

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 7 Apr 2023.
Background: PubMed 16254470Sidlauskas A. Clinical effectiveness of the Twin block appliance in the treatment of Class II Division 1 malocclusion. Stomatologija. 2005;7(1):7-10.
Background: PubMed 32637187Tripathi T, Singh N, Rai P, Gupta P. Comparison of Dentoskeletal Changes, Esthetic, and Functional Efficacy of Conventional and Novel Esthetic Twin Block Appliances among Class II Growing Patients: A Pilot Study. Turk J Orthod. 2020 Jun 1;33(2):77-84. doi: 10.5152/TurkJOrthod.2020.19030. eCollection 2020 Jun.
Background: PubMed 10935956Baccetti T, Franchi L, Toth LR, McNamara JA Jr. Treatment timing for Twin-block therapy. Am J Orthod Dentofacial Orthop. 2000 Aug;118(2):159-70. doi: 10.1067/mod.2000.105571.
Background: PubMed 32904097Shahamfar M, Atashi MHA, Azima N. Soft Tissue Esthetic Changes Following a Modified Twin Block Appliance Therapy: A Prospective Study. Int J Clin Pediatr Dent. 2020 May-Jun;13(3):255-260. doi: 10.5005/jp-journals-10005-1759.
Background: PubMed 28128634van der Plas MC, Janssen KI, Pandis N, Livas C. Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination. Angle Orthod. 2017 Jul;87(4):513-518. doi: 10.2319/102916-779.1. Epub 2017 Jan 27.
Derived from this study: PubMed 41152368Alsilq MN, Youssef M. Soft tissue effects of aesthetic and conventional twin block appliances in the treatment of skeletal class II malocclusion: a randomized controlled trial. Sci Rep. 2025 Oct 28;15(1):37627. doi: 10.1038/s41598-025-21538-w.
Derived from this study: PubMed 39805909Alsilq MN, Youssef M. Dentoskeletal effects of aesthetic and conventional twin block appliances in the treatment of skeletal class II malocclusion: a randomized controlled trial. Sci Rep. 2025 Jan 13;15(1):1879. doi: 10.1038/s41598-025-86219-0.
Individual participant dataSharing planned: No

Related trials for Class II Malocclusion

Enrolling by invitation
Discision as Acceleration Method in Canine Retraction in Orthodontics With Aligner and Fixed Appliances in Young Adults a Split Mouth Study
Bimaxillary Protrusion, Class II Div 1 Malocclusion
Recruiting
Maxillary Arch Distalization With Infrazygomatic Crest Miniscrews for Class II Malocclusion
Class II Malocclusion
Recruiting
Comparing 3D-Printed and Milled Titanium Plates in Jaw Surgery (Le Fort I): Accuracy and Operative Time
Malocclusion, Angle Class II, Malocclusion, Angle Class III
Recruiting
Treatment of Mild Class II Malocclusion in Adult Patients With Clear Aligners Versus Fixed Multibracket Therapy
Malocclusion, Class II Malocclusion
Recruiting
Patient-Reported Outcomes for Different Orthodontic Thermoplastics Used in Clear Aligners
Malocclusion of Anterior Teeth, Malocclusion in Children

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.

Mohammed Najati Alsilq, DDS principal investigator

Department of orthodontics, Damascus University, Syria

Mohamed Youssef, DDS,MSc,PhD study director

Professor of Orthodontics, University of Damascus, Dental School, Damascus, Syria.

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A study testing CTB and ETB in people with Class II Malocclusion, run by Damascus University at 1 site in Syria.

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 4 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: finished, as of the sponsor's last update on 7 Apr 2023. 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 Syria. 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?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

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?

Dentoskeletal mandible changes as measured by tomographic (time frame: Assessment will be done before treatment (T0) and after obtaining 0-1.5 mm overjet and the occlusion settled into a class I or superclass I molar relationship which will be approximately obtained after 8 months (T1).). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05418413, which also lists 7 linked publications.

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 7 Apr 2023.