Modified Herbst Approach for Overbite

Overseen By Nancy Abdelhay, PhD

Age: < 18

Sex: Any

Trial Phase: Academic

Sponsor: University of Alberta

Disqualifiers: Surgery, Mixed dentition, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

Duration: 1 year

40 Participants Needed

Trial Summary

Do I have to stop taking my current medications for this trial?

The trial protocol does not specify whether you need to stop taking your current medications. It seems focused on orthodontic treatments, so it's unlikely that medications would be affected, but you should confirm with the trial organizers.

What data supports the idea that Modified Herbst Approach for Overbite is an effective treatment?

The available research shows that the Modified Herbst Approach is effective for treating overbites, particularly in Class II malocclusions, which involve a misalignment of the jaw. Studies indicate that this treatment can efficiently correct jaw alignment issues with minimal need for patient cooperation. It is noted for its ability to address skeletal and dental changes effectively. However, some studies mention potential side effects, such as changes in the jaw's rotation, which can be managed with additional techniques. Compared to other treatments, the Modified Herbst Approach is highlighted for its efficiency, although it may involve some complications like device breakage or discomfort. ^{1 2 3 4 5}

What safety data exists for the Herbst appliance treatment?

The safety data for the Herbst appliance treatment includes potential complications such as splint loosening, telescope breakage, and low comfort, as noted in a study comparing different types of Herbst appliances. The treatment is effective for Class II malocclusions, especially in growing individuals, but requires posttreatment retention to prevent occlusal relapses. Unfavorable growth and unstable occlusal conditions are risk factors for relapse. The treatment is generally short, and adaptation time is needed for tissues after appliance removal. ^{4 5 6 7 8}

Is the Modified Herbst Approach a promising treatment for overbite?

Yes, the Modified Herbst Approach is a promising treatment for overbite. It can effectively correct dental and skeletal issues, reduce overbite, and improve facial profile. It is also a good alternative to surgery for some patients. ^{1 4 6 9 10}

What is the purpose of this trial?

This study will collect data to try to assess which one of the two management options works better. The first option involves the use of the bite corrector first and then braces, while the second option involves the temporary addition of small support bone screws with the bite corrector later and then braces. Currently, it is not clearly known if there are important differences between the proposed management options. Such approaches are conventionally used in orthodontic practices. The information collected in this study will be used to compare the differences in the nature of the facial, teeth, and bone changes after the treatment. Questions about the experience while using the devices will be asked.

Research Team

Carlos Flores Mir, DSc

Principal Investigator

University of Alberta

Eligibility Criteria

This trial is for individuals with a specific dental condition called Class II skeletal malocclusion, where the lower jaw and teeth are significantly behind the upper ones. They should have all permanent teeth and no missing congenital teeth. It's not suitable for those who only qualify for surgical treatment or don't have at least an end-to-end molar relationship.

Inclusion Criteria

Class II skeletal malocclusion based on PgOLp more than 85 mm and A-OLp more than 75 mm

Early permanent dentition

Perceived potential improvement of facial convexity

Exclusion Criteria

Class II skeletal malocclusion based on PgOLp less than 85 mm and A-OLp less than 75 mm

Congenitally missing teeth

My back teeth do not align properly.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants receive either a hybrid Herbst appliance approach or a modified hybrid Herbst appliance approach with TADs

1 year

Regular visits as per orthodontic treatment schedule

Follow-up

Participants are monitored for changes in facial, dental, and skeletal structures, as well as quality of life assessments

4 weeks

2 visits (in-person)

Treatment Details

Interventions

• Conventional Herbst Approach
• Modified Herbst Approach

Trial Overview The study compares two orthodontic treatments to correct overbites: one uses the Modified Herbst device followed by braces, while the other adds bone screws before using the Herbst device and then braces. The goal is to see which method better improves chin projection and alignment of teeth.

Participant Groups

Group I: Class II type B malocclusion - proclination of upper incisors not indicated - TADs Experimental Treatment 1 Intervention

CA modified hybrid Herbst appliance approach (same hybrid Herbst appliance approach but with the addition of temporary anchorage devices (TADs) in both arches) will be used (alternative treatment). In the upper arch, the TADs would be inserted in the paramedical palatal area. In the lower arch, they would be inserted buccally between the roots of the lower second premolar and the first permanent molar. Elastomeric chains will be used to link these TADs to the first molars in the upper arch and to a buccal bottom on the lower canines.

Group II: Class II type A malocclusion - proclination of upper incisors indicated - TADs Experimental Treatment 1 Intervention

A modified hybrid Herbst appliance approach (same hybrid Herbst appliance approach but with the addition of temporary anchorage devices (TADs) in both arches) will be used (alternative treatment). In the upper arch, the TADs would be inserted in the paramedical palatal area. In the lower arch, they would be inserted buccally between the roots of the lower second premolar and the first permanent molar. Elastomeric chains will be used to link these TADs to the first molars in the upper arch and to a buccal bottom on the lower canines. Upper brackets will be initially bonded and upper incisors proclined until normal inclination values are attained.

Group III: Class II type A malocclusion - proclination of upper incisors indicated - No TADs Active Control 1 Intervention

A hybrid Herbst appliance approach will be used (current available conventional treatment). The upper jaw component will be a maxillary expander secured on the first molar bands. The lower arch would have an uncemented lower acrylic full-coverage splint-type. In between Herbst-type pistons will be used. Upper brackets will be initially bonded and upper incisors proclined until normal inclination values are attained.

Group IV: Class II type B malocclusion - proclination of upper incisors not indicated - No TADs Active Control 1 Intervention

A hybrid Herbst appliance approach will be used (current available conventional treatment). The upper jaw component will be a maxillary expander secured on the first molar bands. The lower arch would have an uncemented lower acrylic full-coverage splint-type. In between Herbst-type pistons will be used.

Conventional Herbst Approach is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Herbst Appliance for:

• Class II malocclusions
• Overbites
• Improvement of chin projection

Approved in European Union as Herbst Device for:

• Orthodontic treatment for Class II malocclusions
• Correction of overbites
• Enhancement of chin projection

Approved in Canada as Herbst Appliance for:

• Treatment of Class II malocclusions
• Improvement of overbites
• Chin projection enhancement

Who Is Running the Clinical Trial?

University of Alberta

Lead Sponsor

Trials

957

Recruited

437,000+

Findings from Research

This study will evaluate a new Herbst appliance design combined with temporary anchorage devices (TADs) to control vertical growth in hyperdivergent Class II patients, aiming to reduce unwanted clockwise rotation of the occlusal plane compared to traditional Herbst treatment.

A total of 44 children will be randomly assigned to receive either standard Herbst treatment or the new approach, with the primary outcome measured through cephalometric analysis of the occlusal plane, ensuring a rigorous assessment of efficacy and safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy of an innovative Herbst appliance with TADs for patients with hyperdivergent class II malocclusion: study protocol for a randomised controlled trial. Wang, Y., Xu, Y., Gong, Z., et al.[2023]

The Herbst-Multibracket appliance (Herbst-MBA) treatment significantly improved the occlusion of Class II:2 malocclusion patients, with the average Peer Assessment Rating (PAR) score decreasing from 23.6 to 5.6 after treatment, indicating effective orthodontic correction.

After a follow-up period of over 2 years, the treatment results remained stable, with 30% of patients rated as 'greatly improved' post-treatment and 33% after follow-up, demonstrating the long-term efficacy of the Herbst-MBA.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficiency and outcome quality of Herbst-Multibracket appliance therapy in Class II:2 patients. Bock, NC., Killat, S., Ruf, S.[2022]

In a study of 30 patients with Class II Division 1 malocclusions, extending the treatment duration with a reinforced Herbst appliance effectively corrected overjet and molar relationships, achieving significant skeletal and dental changes.

After transitioning to fixed appliance therapy, the improvements in overjet and molar relationships were maintained, indicating that the skeletal changes from the Herbst treatment were preserved, with most corrections being dentoalveolar.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cephalometric study of Class II Division 1 patients treated with an extended-duration, reinforced, banded Herbst appliance followed by fixed appliances. Tomblyn, T., Rogers, M., Andrews, L., et al.[2017]

The study analyzed the effects of the Herbst device on 75 growing patients with class II malocclusion, revealing that treatment responses varied based on vertical facial growth patterns.

Hypodivergent patients showed an increase in mandibular divergence during treatment, while hyperdivergent patients experienced a decrease, indicating that facial growth patterns significantly influence the effectiveness of the Herbst appliance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Influence of Vertical Facial Growth Pattern on Herbst Appliance Effects in Prepubertal Patients: A Retrospective Controlled Study. Giuca, MR., Pasini, M., Drago, S., et al.[2022]

In a study of 208 patients with Class II malocclusion, the HT Herbst appliance showed a lower risk of emergencies compared to the acrylic splint Herbst, which had an emergency probability twice as high.

Both types of Herbst appliances had similar treatment times and retreatment probabilities, but the HT Herbst had a higher failure frequency, suggesting that while it may be more reliable in emergencies, it could be less effective overall compared to the traditional acrylic splint.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Acrylic splint Herbst and Hanks telescoping Herbst: a retrospective study of emergencies, retreatments, treatment times and failures. Manni, A., Cozzani, M., Mazzotta, L., et al.[2016]

The study involved 10 adolescents with skeletal class II malocclusions, comparing a modified Herbst appliance with temporary anchorage devices (TADs) to a conventional Herbst appliance over a 9-month treatment period.

Results showed that the modified appliance significantly reduced lower incisor proclination, with only a 1° increase in inclination compared to a 7° increase in the conventional group, suggesting that TADs enhance treatment efficiency and skeletal response.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Mini-implants and the efficiency of Herbst treatment: a preliminary study. Luzi, C., Luzi, V., Melsen, B.[2021]

The Herbst appliance is highly effective for treating Class II malocclusions in growing patients, as demonstrated by clinical cases followed for up to 5 years, but should not be used as a last resort.

Successful outcomes are best achieved in patients with a brachyfacial growth pattern, and post-treatment retention is essential to prevent occlusal relapses after the appliance is removed.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Herbst appliance--its biologic effects and clinical use. Pancherz, H.[2022]

A treatment protocol involving 12 months of stepwise advancement with the Herbst appliance followed by fixed appliances was effective in achieving stable correction of overjet and molar relationships in 16 Class II adult patients.

The study suggests that the long-term stability of the treatment outcomes is significantly influenced by the specific treatment protocol used, emphasizing the importance of a structured approach for mandibular advancement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A protocol for improved stability with Herbst appliance treatment for adults. Austin, DF., Chaiyongsirisern, A., Yang, Y., et al.[2013]

In a study comparing 46 adults who underwent orthognathic surgery with 23 adults treated with the Herbst appliance, both methods successfully achieved Class I occlusion, indicating that Herbst treatment can be a viable alternative to surgery for certain patients.

While both treatments reduced facial profile convexity, the surgery group achieved greater skeletal changes, suggesting that Herbst treatment is effective for occlusal correction but may be less effective for significant facial profile improvements.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Orthognathic surgery and dentofacial orthopedics in adult Class II Division 1 treatment: mandibular sagittal split osteotomy versus Herbst appliance. Ruf, S., Pancherz, H.[2019]

The Herbst appliance significantly intruded the mandibular incisors and maxillary molars while allowing mandibular molars to erupt, effectively reducing deep anterior overbite and increasing lower facial height in 22 treated cases over six months.

While the Herbst appliance had a limited impact on the overall vertical position of the jaws, some patients experienced notable changes, such as posterior rotation of the maxillary complex, highlighting the need for careful treatment planning and retention strategies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Vertical dentofacial changes during Herbst appliance treatment. A cephalometric investigation. Pancherz, H.[2022]

References

1. England pubmed.ncbi.nlm.nih.gov

Efficacy of an innovative Herbst appliance with TADs for patients with hyperdivergent class II malocclusion: study protocol for a randomised controlled trial. [2023]

2. England pubmed.ncbi.nlm.nih.gov

Efficiency and outcome quality of Herbst-Multibracket appliance therapy in Class II:2 patients. [2022]

3. United States pubmed.ncbi.nlm.nih.gov

Cephalometric study of Class II Division 1 patients treated with an extended-duration, reinforced, banded Herbst appliance followed by fixed appliances. [2017]

4. Egypt pubmed.ncbi.nlm.nih.gov

Influence of Vertical Facial Growth Pattern on Herbst Appliance Effects in Prepubertal Patients: A Retrospective Controlled Study. [2022]

5. France pubmed.ncbi.nlm.nih.gov

Acrylic splint Herbst and Hanks telescoping Herbst: a retrospective study of emergencies, retreatments, treatment times and failures. [2016]

6. Germany pubmed.ncbi.nlm.nih.gov

Mini-implants and the efficiency of Herbst treatment: a preliminary study. [2021]

7. United States pubmed.ncbi.nlm.nih.gov

The Herbst appliance--its biologic effects and clinical use. [2022]

8. Germany pubmed.ncbi.nlm.nih.gov

A protocol for improved stability with Herbst appliance treatment for adults. [2013]

9. United States pubmed.ncbi.nlm.nih.gov

Orthognathic surgery and dentofacial orthopedics in adult Class II Division 1 treatment: mandibular sagittal split osteotomy versus Herbst appliance. [2019]

10. Sweden pubmed.ncbi.nlm.nih.gov

Vertical dentofacial changes during Herbst appliance treatment. A cephalometric investigation. [2022]