Evaluating the Impact of Prefabricated Acrylic Splints on Premaxillary Stability in Alveolar Cleft Bone Graft Repairs: a Randomized Controlled Trial

Research question:

The primary research question that drives this study is: Does the use of prefabricated acrylic splints increase the stability of the premaxilla and enhance soft tissue healing and graft stability in patients with bilateral alveolar clefts? The above research question uses the PICO (Patient, Intervention, Comparison, Outcome) format to ensure clarity, structure, and focus on the most important aspects of the investigation P - Population: Bilateral alveolar cleft patients I - Intervention: Use of prefabricated acrylic splints C - Comparison: in comparison to the control group that did not use acrylic splints O - Outcome: Enhance premaxillary stability vertical and horizontal assessed by (Lateral Cephalometric Analysis (Radiographically), soft tissue healing, and graft stability

Statement of the problem:

Congenital bilateral alveolar clefts affect many patients from diverse backgrounds, impacting their quality of life . These clefts involve separation of the upper jaw from one alveolus to another, often accompanying cleft lip and palate . Both esthetic and functional issues arise due to impacts on speech, feeding, breathing and appearance from childhood onward . Bone grafting is necessary to reconstruct the maxillary anatomy in bilateral alveolar clefts Premaxillary stability is especially crucial, as it influences bone graft incorporation and craniofacial development . Studies report premaxillary mobility still occurs in 20-40% of treated bilateral clefts at one year post-grafting using standard fixation methods . This instability disrupts integration of autogenous bone grafts and impedes future reconstructive care such as orthodontics . While bone grafting aims to reconstruct the maxilla, premaxilla fixation techniques may remain inadequate to guarantee stability. An alternative is needed to optimize patient outcomes for this patient population.

Rationale for conducting the research:

Bilateral alveolar clefts pose significant management challenges, with current treatments like autogenous bone grafting showing instability in up to 40% of cases within a year, risking graft failure and aesthetic issues . Prefabricated acrylic splints may offer a minimally invasive alternative, potentially improving bone graft outcomes and premaxillary stability, crucial for speech, feeding, and respiration . This study evaluates the efficacy of acrylic splinting versus traditional open healing, aiming to enhance patient outcomes and reduce healthcare costs associated with this congenital condition. This research underscores the need for evidence-based, minimally invasive treatments that can improve quality of life and guide clinical practices for managing bilateral alveolar clefts.

Review of literature:

The existing body of literature on bilateral alveolar clefts and their management reflects several inadequacies and gaps in the evidence base. Bilateral alveolar clefts present unique challenges that have not been fully addressed in the literature on cleft lip and palate management . Limited evidence suggests more focused research in this area. The prevailing treatment options for bilateral alveolar clefts predominantly involve surgical bone grafting procedures. These grafting techniques have shown varying success rates, with factors such as graft quality, surgical technique, and premaxillary stability influencing outcomes. However, the specific challenges posed by bilateral alveolar clefts have not been addressed comprehensively in the existing literature. While grafting procedures have undoubtedly improved the lives of countless patients, there remains a need for more targeted interventions that can enhance premaxillary stability and graft success, particularly in the context of bilateral alveolar clefts . The proposed use of prefabricated acrylic splints represents a novel and innovative approach to address these inadequacies. These splints are designed to provide consistent and reliable support to the premaxilla during the critical early phases of healing following grafting procedures. By minimizing premaxillary mobility, they have the potential to enhance graft success rates, improve premaxillary stability, and enhance the overall outcomes of bilateral alveolar cleft repairs.

Explanation for choice of comparators:

, standard bone grafting without acrylic splints is considered the 'gold standard' for treating alveolar clefts. Using normal repair as the comparator allows for a clear assessment of the possible advantages and challenges of incorporating acrylic splints into existing best practices.

7\. Objectives:

Aim of the Study The primary aim of this study is to assess the impact of prefabricated acrylic splints on premaxillary stability, soft tissue healing, and graft stability in patients with bilateral alveolar clefts.

Hypothesis:

Null Hypothesis (H0): Bilateral alveolar cleft patients who receive prefabricated acrylic splints have similar premaxillary stability, soft tissue healing, and graft stability.

Alternative Hypothesis (H1): Prefabricated acrylic splints improve premaxillary stability, soft tissue healing, and graft stability in bilateral alveolar cleft patients.

The above hypotheses are neutral and not biased. The study tests these hypotheses to obtain objective and evidence-based conclusions about prefabricated acrylic splints for bilateral alveolar cleft repairs.

8\. Trial design: The proposed trial is RCT, the gold standard for assessing intervention efficacy. It will be a parallel group RCT, a commonly controlled comparison of two interventions. Two arms will represent the control and test groups in the trial. This trial aims to determine whether prefabricated acrylic splints are better than no splints in a 1:1 allocation ratio.

Allocation Ratio and Framework:

This RCT has a 1:1 allocation ratio, so the control and test groups will each receive the same number of participants. This balanced allocation ensures equal group sizes, reducing bias and enabling a more robust comparison between the two interventions.

Superiority Trial This RCT is a superiority trial to show that prefabricated acrylic splints improve premaxillary stability, soft tissue healing, and graft stability in bilateral alveolar cleft patients. Superiority trials prove the new intervention works better than the control. In this trial, the null hypothesis (H0) states that the two interventions are similar, while the alternative hypothesis (H1) states that prefabricated acrylic splints are better. A superiority trial is needed to determine if the new intervention improves patient outcomes meaningfully and clinically. It is important to determine if prefabricated acrylic splints improve premaxillary stability, soft tissue healing, and graft success in bilateral alveolar cleft patients. A successful superiority trial could support this intervention in clinical practice, improving patient care and outcomes. A 1:1 allocation ratio reduces allocation bias by balancing the study with equal numbers of participants in each group. This design makes control and test group comparisons clear and robust. This trial will inform clinical practice and build knowledge of bilateral alveolar cleft management.

III. Methods

A) Participants, interventions \& outcomes 9. Study settings: This randomized controlled trial will be conducted in Cairo hospital (Abu El-Reesh El-Mounira Children University Hospital). To ensure clinical facilities, medical expertise, and target patient access, this study will be conducted in a hospital. The population density of Cairo and prevalence of bilateral alveolar clefts make it ideal for this research . Cairo study sites will be available upon request and documented in the trial.

10\. Eligibility criteria:

A suitable and representative sample will be selected by setting trial participant eligibility criteria. the inclusion and exclusion criteria will consider demographics, disease severity, prior treatment, diagnostics, and other factors. This trial must balance accurately representing the target population with avoiding overly restrictive selection criteria.

Inclusion Criteria

1. Patients diagnosed with bilateral alveolar clefts. 2. Age 8- 12 within the specified range. 3. Willingness to comply with trial requirements.

Exclusion Criteria

1. Patients with allergy use acrylic splints. 2. Severe medical conditions such as mental retardation. 3. Inability to provide informed consent or assent.

Operator-dependent interventions will have clear eligibility criteria for care providers and centers to ensure consistency in administration. To improve external validity and clinical applicability, the trial will avoid overly restrictive participant selection . To ensure generalizability, trial participants must reflect the diversity of the target population.

11\. Interventions

All surgical procedures will be conducted under general anesthesia with nasotracheal intubation, and a first-generation cephalosporin will be administered as antibiotic prophylaxis prior to incision .Autogenous bone grafts will be harvested from the anterior iliac crest using a pediatric minimally invasive technique, involving a 2 cm skin incision made 1 cm lateral to the iliac crest, meticulously dissected to preserve soft tissue. pain management strategies will be employed postoperatively to ensure comprehensive pain control and enhance patient comfort throughout the recovery period.

For the alveolar cleft repair, a sulcular incision will be made to develop full thickness mucoperiosteal advancement flaps extending into the cleft, with careful elevation of buccal flaps above the piriform rim. The bone graft will be contoured to fill the defect, ensuring cortical bone contacts the nasal lining and cancellous bone chips fill remaining spaces. Closure will be performed using interrupted sutures, starting with the nasal floor and followed by oral closure, with a stabilizing horizontal mattress suture for added stability.

Patients will be preoperatively assigned in a 1:1 ratio to receive either a custom-made prefabricated acrylic splint, designed and trimmed using digital software like Mimics for accurate fit and stabilization of the premaxilla , or no splint, allowing for comparison of premaxillary stability between groups. Both groups will follow a standardized postoperative protocol that includes regular follow-up assessments for premaxillary stability, wound healing, and potential complications, using clinical examination and radiographic evaluation. Data collected will be analyzed using statistical methods to compare outcomes between the experimental and control groups, focusing on premaxillary stability as the primary outcome, with wound healing and complications as secondary measures.

12\. Outcomes: The trial will evaluate primary, secondary, and other outcomes with specific and measurable units.

The primary outcome should be:

* Premaxillary stability vertical and horizontal assessed by (Lateral Cephalometric Analysis (Radiographically) at 6 months: Perform lateral cephalometric analysis using images generated from Cone Beam Computed Tomography (CBCT) to assess changes in premaxillary position and stability demographically. This radiographic method will help in quantifying any shifts or instability in the premaxilla over time. Soft Tissue Healing: Evaluated based on clinical signs of healing, such as absence of erythema, edema, and wound dehiscence. * Graft Stability: Radiographic Assessment: Use radiographic techniques, including standard X-rays or CBCT, to evaluate the integration, position, and retention of the bone graft. This will involve checking for signs of graft resorption or failure and measuring overall graft stability over time.

Secondary objectives

* Assessment of Bone Gain and premaxillary stability: Assessed by Cone Beam Computed Tomography (CBCT) Following Periotest Assessment (Clinically): Use the Periotest device to quantitatively measure the mobility and sta

• Secondary Outcome Measures: Outcome Measure Name: 1) Soft Tissue Healing 2) Outcome Measure Name: Graft Stability [Срок оценки: 6 MONTHS]