Comparing the Impact of Rubber Bands on Teeth Straightening with Clear Aligners Versus Traditional Braces: a Clinical Study

NCT ID: NCT06832475

Last Updated: 2025-02-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-09-01
• Study Completion Date: 2024-12-15

Brief Summary

Aim: To analyze the inclination of lower incisors in patients with Class II malocclusion treated with elastics and clear aligners compared to a group wearing the same elastics and fixed appliance. A sample of 40 patients (19M and 21F), mean age 15.4±1.8 years, was randomly divided in two groups: Clear aligner group (CA), Fixed appliance group (FA). The subjects were selected according to inclusion criteria: full permanent dentition (excluding third molars), Class II molar relationship (2,5-4 mm), no history of orthodontic treatment.

Detailed Description

Trial design: Prospective two-arms parallel group randomized clinical trial with 1:1 allocation ratio.

Materials and Methods: A sample of 40 patients (19M and 21F), mean age 15.4±1.8 years, was collected from the Department of Orthodontics at Policlinico "Tor Vergata" of Rome, and it was randomly divided in two groups: Clear aligner group (CA), Fixed appliance group (FA). The subjects were selected according to inclusion criteria: full permanent dentition (excluding third molars), Class II molar relationship (2,5-4 mm), no history of orthodontic treatment. Results: In the short term (T1-T0=18 months), the analysis of the results showed no statistically significant changes in all evaluated parameters. Therefore, there is no statistically significant change in the inclination of the lower incisors between the two groups.

Conclusions: The use of Class II elastics in CA group showed a better control of the lower incisors' inclination, compared to the FA group, even if the difference is not significant.

Trial registration: ClinicalTrials.gov (registration number: ..........)

Conditions

Class II Malocclusion; IMPA Angle

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Class II malocclusion with clear aligners

For the groupteated with Clear Aligners (CA), the treatment provided the application of Invisalign clear aligner system and the absence of any other auxiliaries apart from Invisalign optimized attachments. Each subject was instructed to wear aligners for 22 hours per day, except during meals and oral hygiene procedures and to replace aligners once a week, always the same day of the week. Every six stages the clinician personally checked the good aligner fitting, the position of the attachments and the patient collaboration.

Group Type: EXPERIMENTAL

clear aligners and elastics

Intervention Type: DEVICE

For the Fixed Appliance group, the straight wire treatment included an aligning and leveling phase, achieved by using Nickel-Titanium arches (0.016/0.019 × 0.025 arc sequence) and a phase with heavier stainless steel rectangular arches (0.019 × 0.025); during this last treatment phase patients were instructed to use Class II elastics for at least 16 h/day.

Pre- (T0) and post-treatment (T1) lateral cephalogram were collected from all selected patients. Treatment time was an average of 18 months (T1-T0=18 months).

class 2 elastics

Intervention Type: DEVICE

Class II malocclusion is the most common malocclusion, and it is one of the main reasons for people to undergo orthodontic treatment. This alteration is characterized by an improper relationship between the maxillary and mandibular arches because of skeletal or dental discrepancies or a combination of both . The treatment protocols may considerably vary depending on professional skills, malocclusion severity and patient compliance . Among all the well-known techniques, it is important to mention the Class II elastics , used to camouflage mild skeletal Class II or to treat mild to moderate Class II occlusal relationship.

During the correction of Class II malocclusions by means of inter-arch elastics, special attention should be paid to the position of the lower incisors.

Class II malocclusion with fixed appliance and elastics

For the group treated with Fixed Appliance (FA), the straight wire treatment included an aligning and leveling phase, achieved by using Nickel-Titanium arches (0.016/0.019 × 0.025 arc sequence) and a phase with heavier stainless steel rectangular arches (0.019 × 0.025); during this last treatment phase patients were instructed to use Class II elastics for at least 16 h/day.

Pre- (T0) and post-treatment (T1) lateral cephalogram were collected from all selected patients. Treatment time was an average of 18 months (T1-T0=18 months).

Group Type: EXPERIMENTAL

class 2 elastics

Intervention Type: DEVICE

Class II malocclusion is the most common malocclusion, and it is one of the main reasons for people to undergo orthodontic treatment. This alteration is characterized by an improper relationship between the maxillary and mandibular arches because of skeletal or dental discrepancies or a combination of both . The treatment protocols may considerably vary depending on professional skills, malocclusion severity and patient compliance . Among all the well-known techniques, it is important to mention the Class II elastics , used to camouflage mild skeletal Class II or to treat mild to moderate Class II occlusal relationship.

During the correction of Class II malocclusions by means of inter-arch elastics, special attention should be paid to the position of the lower incisors.

Interventions

clear aligners and elastics

For the Fixed Appliance group, the straight wire treatment included an aligning and leveling phase, achieved by using Nickel-Titanium arches (0.016/0.019 × 0.025 arc sequence) and a phase with heavier stainless steel rectangular arches (0.019 × 0.025); during this last treatment phase patients were instructed to use Class II elastics for at least 16 h/day.

Pre- (T0) and post-treatment (T1) lateral cephalogram were collected from all selected patients. Treatment time was an average of 18 months (T1-T0=18 months).

Intervention Type: DEVICE

class 2 elastics

Class II malocclusion is the most common malocclusion, and it is one of the main reasons for people to undergo orthodontic treatment. This alteration is characterized by an improper relationship between the maxillary and mandibular arches because of skeletal or dental discrepancies or a combination of both . The treatment protocols may considerably vary depending on professional skills, malocclusion severity and patient compliance . Among all the well-known techniques, it is important to mention the Class II elastics , used to camouflage mild skeletal Class II or to treat mild to moderate Class II occlusal relationship.

During the correction of Class II malocclusions by means of inter-arch elastics, special attention should be paid to the position of the lower incisors.

Intervention Type: DEVICE

Other Intervention Names

fixed appliance and elastics

Eligibility Criteria

Inclusion Criteria

• full permanent dentition (excluding third molars), Class II molar relationship (2,5-4 mm), no or moderate crowding (0- 3 mm) no history of orthodontic treatment.

Exclusion Criteria

• not completed permanent dentition, skeletal Class II or dental Class II more than 4 mm, crowding more than 3 mm, subjects already treated with iother orthodontic appliances.

• Minimum Eligible Age: 13 Years
• Maximum Eligible Age: 17 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Rome Tor Vergata

OTHER

Sponsor Role: lead

Responsible Party

Giuseppina Laganà

EFFECTS OF CLASS II ELASTICS DURING TREATMENT WITH CLEAR ALIGNERS VS FIXED APPLIANCE: A RANDOMIZED CLINICAL TRIAL

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

University of Tor Vergata

Rome, Rome, Italy

Countries

Italy

References

Lagana G, Malara A, Lione R, Bollero P, Cozza P. Effects of Class II elastics on lower incisors during treatment with clear aligners vs. fixed appliance: a randomized clinical trial. Front Dent Med. 2025 Jul 10;6:1613037. doi: 10.3389/fdmed.2025.1613037. eCollection 2025.

Reference Type: DERIVED

PMID: 40708614 (View on PubMed)

Other Identifiers

Ethical Commitee n. 24/23

Identifier Type: -

Identifier Source: org_study_id