The goal of this clinical trial is to evaluate the effectiveness of a novel lip bumper with an integrated distal shoe in preventing second molar impaction in children aged 8-10 years with anterior open bite during the mixed dentition stage.

The main questions it aims to answer are:

• Does the integrated distal shoe significantly reduce the risk of second molar impaction compared to conventional lip bumpers?
• Does the appliance improve anterior open bite correction and influence lower incisor inclination?

Researchers will compare Group I (lip bumper with distal shoe) to Group II (conventional lip bumper) to see if the modified appliance prevents mesial drift of first molars and improves eruption outcomes of second molars.

Participants will:

• Undergo initial records including panoramic and cephalometric radiographs, study models, and intraoral photos
• Be fitted with one of the two appliances and followed up every 6 weeks over a 12-month period
• Receive radiographic and clinical evaluation of second molar eruption
• Complete assessments related to overbite changes, incisor inclination, comfort, and compliance This trial seeks to inform early orthodontic protocols and may offer a dual-function solution for both molar guidance and open bite correction.

This clinical research study is focused on improving early orthodontic care for children who have an anterior deep bite-a condition where the upper teeth excessively overlap the lower front teeth-and are at risk of second molar impaction, a complication where the posterior teeth do not emerge properly. Left untreated, these issues can lead to long-term dental problems including poor bite alignment, crowding, or the need for surgical intervention.

Orthodontists often use a device called a lip bumper to reduce pressure from the lips on the lower front teeth, making room for crowded teeth and promoting healthy jaw development. However, a well-known downside of using a lip bumper-especially in young children-is that it can cause the first molars to drift forward. This forward movement can block the path for the second molars, increasing the risk that they will not erupt normally.

This study introduces a novel orthodontic appliance that aims to solve both problems at once. The new device combines the benefits of a traditional lip bumper with a "distal shoe"-a small guiding component that helps maintain proper space for the second molars to erupt. By doing so, it seeks not only to correct deep bite problems but also to prevent the common and serious issue of molar impaction.

The study will involve children between the ages of 8 and 10, a key stage of dental development. Participants will receive either the new dual-purpose device or a standard lip bumper and will be monitored over the course of a year. Throughout this period, researchers will examine how the teeth are moving, whether the posterior molars are erupting properly, and how well the deep bite is improving.

In addition to clinical evaluations, the study will gather feedback from children and their parents about comfort, ease of use, and any issues related to the appliance. Understanding patient experience is a vital part of assessing whether this new approach can be widely recommended in pediatric dental care.

Ultimately, this research aims to offer a more comprehensive and preventive solution for young patients undergoing early orthodontic treatment. If the new appliance proves effective, it could significantly reduce the need for more complex procedures later in life and promote better long-term dental health.

Ethical safeguards, including informed consent from parents and assent from participating children, are in place to ensure safety and understanding. The study has received institutional ethics approval and will be conducted under regular clinical monitoring.

Inclusion Criteria:

• Age between 8 and 11 years
• In mixed dentition stage (presence of permanent first molars and incisors; unerupted second molars)
• Presence of an anterior deep bite of ≥ 2 mm (measured vertically between upper and lower incisors)
• Class I or mild Class II malocclusion
• Good general health with no systemic conditions that may affect dental development or treatment
• Written informed consent obtained from the parent or legal guardian and assent from the child

Exclusion Criteria:

• History of previous orthodontic treatment
• Presence of craniofacial anomalies (e.g., cleft lip/palate) or syndromic conditions
• Diagnosis of systemic diseases that affect bone metabolism or craniofacial growth (e.g., juvenile rheumatoid arthritis, osteogenesis imperfecta)
• Evidence of poor oral hygiene or active caries requiring urgent dental care
• Use of any medication known to affect dental development (e.g., long-term corticosteroids, antiepileptics)
• Behavioral or developmental disorders that would preclude cooperation with appliance wear or study procedures

The following de-identified individual participant data (IPD) will be shared:

Demographic data: age, sex, and baseline dental classification (e.g., type of malocclusion)

Radiographic measurements: second molar eruption angle and position at baseline and 12 months

Cephalometric data: baseline and post-treatment incisor mandibular plane angle (IMPA)

Overbite measurements: baseline and post-treatment vertical overlap (in mm)

Patient-reported outcomes: responses from comfort and compliance questionnaires

Adverse event reports: type, frequency, and severity of any soft tissue complications

Compliance assessments: clinician-rated appliance wear and follow-up adherence

All shared data will be fully anonymized in accordance with ethical standards and privacy regulations.

IPD Availability Timeline

Start Date for IPD Availability:

Six months after publication of the primary study results in a peer-reviewed journal.

End Date for IPD Availability:

Five years from the start date of data sharing.

During this period, de-identified individual participant data and related supporting documents (such as the study protocol and statistical analysis plan) will be made available to qualified researchers upon reasonable request and subject to data use agreements.