Evaluation of Orthodontic Treatment Modalities for Obstructive Sleep Apnoea: A Systematic Review

Obstructive sleep apnoea (OSA) poses a significant health burden globally, necessitating effective intervention strategies to mitigate its adverse consequences. Orthodontic treatment modalities offer promising avenues for addressing OSA by targeting the underlying anatomical abnormalities and restoring unobstructed airflow during sleep. This systematic search was conducted across multiple electronic databases using predefined search terms and inclusion criteria. Studies eligible for inclusion encompassed a range of study designs, including randomized controlled trials, prospective and retrospective studies, clinical trials, and observational studies. Outcome measures included changes in apnoea-hypopnoea index (AHI), oxygen saturation levels, polysomnographic variables, skeletal/cephalometric changes, nasal parameters, upper airway morphology, and clinical symptoms. Initially, 756 records were identified through database searches, with 21 studies meeting the inclusion criteria after meticulous screening and selection. Orthodontic interventions, including rapid maxillary expansion (RME), personalized oral appliances, mandibular positioning devices, and comprehensive orthodontic protocols, demonstrated significant promise in ameliorating OSA symptoms among paediatric populations. Improvements in AHI, nasal resistance, sleep parameters, and upper airway dimensions were consistently observed across various studies, highlighting the potential of orthodontic treatments in mitigating OSA severity. This systematic review underscores the efficacy of orthodontic treatment modalities in addressing OSA among paediatric populations. Despite certain limitations in study design and outcome measures, the review emphasizes the need for further well-designed randomized controlled trials to validate and optimize these interventions for paediatric patients with OSA. Enhanced understanding and implementation of orthodontic treatments hold promise for alleviating the burden of OSA on global health and well-being.


Introduction And Background
Obstructive sleep apnoea (OSA) looms as a formidable threat to global public health, casting its pervasive shadow over millions worldwide [1].Defined by recurrent episodes of upper airway obstruction during sleep, OSA disrupts the natural cycle of rest and rejuvenation, predisposing affected individuals to a cascade of adverse health consequences [1,2].Among its repercussions, hypertension, cardiovascular disease, impaired cognitive function, and diminished quality of life stand prominent, underscoring the urgent need for efficacious intervention strategies [2].In this context, orthodontic treatment modalities emerge as promising contenders in the ongoing battle against OSA, offering a diverse spectrum of approaches to address underlying anatomical aberrations and restore unobstructed airflow during sleep [3].
The landscape of orthodontic interventions for OSA is characterized by a mosaic of techniques and technologies, each imbued with unique nuances and considerations in its application [2,3].Within this complex milieu, the pursuit of optimal therapeutic efficacy and patient-centric outcomes necessitates a comprehensive evaluation of existing modalities, guiding clinicians and researchers toward informed decision-making and evidence-based practice [3].Within this framework, the present systematic review endeavours to illuminate the landscape of orthodontic treatment for OSA, synthesizing empirical evidence and clinical insights to inform best practices and foster advancements in the field.
At the crux of discussions surrounding orthodontic interventions for OSA lies the recognition of anatomical factors predisposing individuals to upper airway compromise during sleep [4].From retrognathic mandibles to deficient maxillary dimensions and aberrant soft tissue dynamics, an array of structural anomalies may conspire to impede airflow and precipitate OSA [5].In response, orthodontic modalities such as mandibular advancement devices (MADs) and maxillary expansion appliances (MEAs) have emerged as frontline interventions, leveraging the principles of craniofacial growth modification to alleviate airway constriction and mitigate OSA severity [6][7].
MADs, revered for their simplicity and non-invasiveness, exert their therapeutic effects by advancing the mandible relative to the maxilla, thereby enlarging the pharyngeal airspace and reducing the propensity for airway collapse [7].Extensive documentation attests to their efficacy in improving polysomnographic parameters and ameliorating symptoms of OSA, positioning them as first-line options for mild to moderate cases and as adjunctive therapies in severe presentations [8].Conversely, MEAs operate on the premise of maxillary expansion, employing controlled forces to augment maxillary dimensions and alleviate nasal obstruction, thus facilitating nasal breathing and mitigating OSA severity [9].While their utility in paediatric populations and skeletally immature individuals is firmly established, the evidence supporting their efficacy in adult populations remains equivocal, necessitating further investigation and refinement [10].
Beyond conventional orthodontic appliances, emerging technologies such as temporary anchorage devices (TADs) and custom-designed mandibular advancement appliances herald new frontiers in OSA management, proffering precision-engineered solutions tailored to individualized anatomical considerations [11,12].TADs, characterized by their biomechanical versatility and targeted application, afford precise control over dental and skeletal movements, facilitating the implementation of complex treatment protocols with heightened predictability and efficacy [11].Similarly, custom-designed MADs, fabricated through computer-aided design and three-dimensional printing technologies, offer unparalleled customization and patient comfort, elevating the standard of care in OSA management to unprecedented heights.
However, amidst the burgeoning landscape of orthodontic treatment modalities for OSA, a paucity of highquality evidence and standardized outcome measures persists, impeding the establishment of definitive treatment algorithms and guidelines [12,13].By synthesizing existing evidence and delineating knowledge gaps, the present systematic review endeavours to chart a course towards enhanced clinical decision-making and improved patient outcomes in the realm of orthodontic treatment for OSA.This systematic review aims to evaluate the effectiveness of various orthodontic treatment modalities in managing OSA among paediatric populations, synthesizing empirical evidence and clinical insights to inform best practices and guide future research directions.

Materials and methodology
This systematic review meticulously adhered to the stringent guidelines delineated in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), thus ensuring a systematic and standardized approach to reporting.Designed to enhance the transparency and quality of systematic reviews, the PRISMA guidelines furnish a comprehensive checklist and flow diagram that reviewers are required to follow.This project was self-financed, and the protocol was registered at the PROSPERO site (registration number: CRD42024523135).apnoea-hypopneaindex (AHI) Before starting the review, we carefully developed a comprehensive methodology following the esteemed Cochrane Handbook for Systematic Reviews of Interventions.This handbook is highly regarded for its detailed guidance on every step of the systematic review process, from formulating research questions to selecting and evaluating studies, extracting data, and assessing bias.Our methodology included specific criteria for including and excluding studies, strategic methods for searching relevant databases, and detailed protocols for synthesizing and analysing data.We adopted this rigorous approach to minimize bias and ensure the reliability and validity of the review's findings.

Review Question
What are the outcomes of different orthodontic treatments for obstructive sleep apnoea (OSA)?It aims to analyse how effective various orthodontic interventions are in managing OSA, highlighting their pros and cons.By summarizing existing evidence, this review aims to guide clinical decisions and improve treatment approaches for OSA patients.

Search Strategy
When crafting a search strategy for the systematic review "Assessment of Orthodontic Treatments for Obstructive Sleep Apnoea," it was crucial to adopt a thorough and methodologically sound approach to find pertinent literature.This strategy targeted studies exploring orthodontic interventions for obstructive sleep apnoea (OSA), a condition marked by airway obstruction during sleep, causing breathing disruptions and insufficient oxygen levels.
To thoroughly gather relevant literature, electronic databases like PubMed, Embase, Cochrane Library, and Scopus were utilized, as they contained a wide range of peer-reviewed articles in orthodontics and sleep medicine.A combination of keywords was used to capture studies on orthodontic treatments and OSA, including terms like "Orthodontic treatment," "Obstructive sleep apnea," and "Continuous positive airway pressure (CPAP)."Boolean operators (AND, OR) helped construct search strings efficiently by combining these keywords.For instance, one search string was: ("Orthodontic treatment" OR "Orthodontic appliances") AND ("Obstructive sleep apnea" OR "OSA") AND ("Systematic review").
To refine the search results and ensure relevance, filters like publication date (e.g., last 20 years) and language (e.g., English) were applied.Manual screening of reference lists from relevant articles and systematic reviews complemented electronic searches, helping to identify additional studies.Grey literature sources, such as conference proceedings and clinical trial registries, were also searched for unpublished or ongoing research.Collaboration with experts and information specialists enhanced the search strategy.By doing so, the systematic review aimed to synthesize evidence on orthodontic treatments for OSA, providing insights for clinical practice and future research.

Inclusion and Exclusion Criteria
A variety of robust study designs, such as randomized controlled trials (RCTs), cohort studies, and observational studies, were included.The population study comprised paediatric patients diagnosed with OSA.Different orthodontic treatments for OSA were evaluated, including MADs, maxillomandibular advancement (MMA), orthognathic surgery, and orthodontic appliances.Studies comparing these treatments to each other, placebo, or no treatment were also considered.Outcome measures included changes in apnoea-hypopnoea index (AHI), oxygen saturation levels, quality of life indicators, and treatment adherence.Peer-reviewed articles, conference abstracts, and dissertations were included.
Animal studies, case reports, editorials, letters, and reviews were excluded.Additionally, studies focusing only on adult populations or individuals with syndromic conditions were not considered.Investigations of treatments other than orthodontic interventions for OSA, such as continuous positive airway pressure (CPAP) therapy or surgical interventions not involving orthodontic techniques, were not included.Studies without a comparison group or with poorly controlled groups were also excluded.Any studies lacking relevant outcome measures for managing OSA were disregarded.Lastly, due to translation resource limitations, studies not in English were excluded.Adherence to PRISMA statement guidelines and a thorough search methodology enhanced the reliability and validity of this systematic review (Figure 1).The determination of inclusion and exclusion criteria was guided by the aspects of Study design, Participants, Interventions, Comparisons, and Outcomes (SPICO) (Table 1).Two researchers collaborated on the search and screening process, achieving a substantial inter-rater agreement (κ = 0.83), ensuring reliability.The process involved four stages: Stage 1 excluded irrelevant citations, Stage 2 assessed titles and abstracts against inclusion criteria, and Stage 3 involved meticulous assessment by two independent reviewers, excluding studies with inappropriate designs or referencing deficiencies.Uncertainties were resolved through consensus or consultation with a second reviewer.In Stage 4, selected articles were subjected to a thorough examination and data extraction.Clinical methodologies and outcomes were critically appraised for reliability and relevance.This structured approach ensured methodological robustness and relevance of included articles.Adherence to high standards enhanced credibility and validity, reflected in the substantial κ coefficient.

Data Extraction
Initially, the primary author meticulously performed data extraction, ensuring accuracy.Subsequently, the second author reviewed and refined the data for completeness.

Assessment of Risk of Bias
The assessment of bias in this systematic review employed the ROBINS-I (Risk Of Bias In Non-randomised Studies -of Interventions) tool, designed for non-randomized intervention studies.Each study was subjected to meticulous evaluation across several domains.Firstly, confounding bias was scrutinized to ascertain whether relevant confounders were adequately addressed and adjusted for.Studies lacking such adjustments were deemed to have a higher risk of bias.Secondly, selection bias was assessed by examining participant recruitment methods to ensure comparability between groups.Studies with flawed selection processes were flagged for higher bias (Table 3).

TABLE 3: Assessment of the risk of bias
Intervention classification bias was also scrutinized to ensure consistent and accurate intervention categorization.Deviations from intended interventions were analysed to assess participant adherence and management of deviations.Studies with uncontrolled deviations were deemed to have higher bias.Missing data bias was another focal point, emphasizing how missing data were addressed and their impact on results.Inadequate handling of missing data raised concerns about bias.Additionally, outcome measurement bias was evaluated based on measurement method reliability and consistency.Inconsistent or unreliable measurements increased the risk of bias.Lastly, outcome reporting bias was examined to identify selective outcome reporting.Studies failing to report all prespecified outcomes or showing selective reporting were considered to have a higher risk of bias.The overall bias risk for each study was synthesized from these assessments, offering a comprehensive evaluation of methodological rigour and potential biases.The structured approach provided insights into the reliability and validity of the reviewed studies, enhancing the credibility of the systematic review's findings.

Results
Initially, we found 756 records through database searches, plus two more from alternative sources, totalling 758.After removing duplicates, we had 714 unique records.Screening led to assessing 49 records for eligibility, with 665 exclusions based on preset criteria.We then scrutinized full-text articles, excluding 28 studies for various reasons.Ultimately, 21 studies met our inclusion criteria and were included in the systematic review.This methodical process allowed for a thorough examination of the literature, enabling a comprehensive synthesis of evidence relevant to our research question.
The systematic review on the evaluation of orthodontic treatment modalities for OSA encompasses a comprehensive analysis of various studies focused on addressing this prevalent sleep disorder in paediatric populations.Across the diverse studies reviewed, orthodontic interventions showed significant promise in ameliorating symptoms associated with OSA among children.

Discussion
The systematic review provides a comprehensive analysis of various orthodontic interventions aimed at managing OSA in children.The discussion section synthesizes the findings from multiple studies to elucidate the efficacy and impact of different orthodontic approaches in addressing OSA symptoms and improving patients' quality of life.
In a prospective clinical trial by Villa et al. (2007), children with malocclusion and symptoms of OSA underwent orthodontic treatment with rapid maxillary expansion (RME) [12].The study observed significant improvements in OSA symptoms, AHI, and other relevant parameters, indicating the potential of RME in alleviating OSA in paediatric patients.Similarly, Pirelli et al. ( 2004) investigated the effects of RME in children with maxillary constriction and OSA [13].Their prospective trial demonstrated notable enhancements in nasal resistance, reduction in AHI, and improvements in sleep parameters post-treatment, highlighting the favourable outcomes associated with RME in managing OSA.
In a randomized controlled study led by Villa et al. (2002), personalized oral appliances for mandibular positioning showed promising results in reducing tonsillar hypertrophy and relieving daytime and nighttime symptoms in children with OSA [14].This underscores the effectiveness of personalized oral appliances as a therapeutic option for paediatric OSA.Guilleminault et al. (2011) compared the outcomes of adeno-tonsillectomy followed by orthodontics versus orthodontics followed by adeno-tonsillectomy in prepubertal children with OSA [15].Both groups experienced improvements in AHI and respiratory disturbance index (RDI), highlighting the significance of multimodal approaches in managing paediatric OSA.[25,26].These studies offer valuable insights into alternative orthodontic modalities for managing OSA in children.
While the systematic review on orthodontic treatment for paediatric OSA offers valuable insights, it's important to acknowledge its limitations.The included studies varied in design, sample size, and follow-up duration, potentially introducing heterogeneity and limiting generalizability.Most studies relied on subjective measures, which could be prone to observer bias and may not fully capture OSA's multifactorial nature.Additionally, many studies were observational or retrospective, lacking rigorous control groups or randomization, thus limiting causal inferences.The long-term sustainability of orthodontic interventions remains unclear due to short follow-up periods in some studies.While the review covered various orthodontic modalities, including RME and personalized oral appliances, further research, especially welldesigned randomized controlled trials, is needed to compare their effectiveness, optimal timing, and duration.Despite these limitations, the review highlights the potential of orthodontic treatments in addressing paediatric OSA, emphasizing the need for future research to fill existing gaps and strengthen the evidence base in this area.

Conclusions
In summary, this systematic review thoroughly evaluates various orthodontic treatments for pediatric obstructive sleep apnoea (OSA).The analysis highlights the effectiveness of interventions like rapid maxillary expansion (RME), personalized oral appliances, and mandibular positioning devices in alleviating OSA symptoms and enhancing clinical outcomes in children.Although some limitations exist in study design and outcome measures, the review underscores the promising role of orthodontic treatments in managing OSA in children.Further well-designed randomized controlled trials are needed to confirm and refine these interventions for pediatric OSA patients.

FIGURE 1 :
FIGURE 1: PRISMA flowchart for this systematic review PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

TABLE 1 : SPICO criteria for this systematic review
SPICO: Study design, Participants, Interventions, Comparisons, and Outcomes; OSA: obstructive sleep apnoea; AHI: apnoea-hypopnoea index; SaO2: oxygen saturation Screening and Selection 2024 Gorikapudi et al.Cureus 16(7): e65161.DOI 10.7759/cureus.65161 Each eligible full-text article underwent independent data extraction, following a standardized format in Microsoft Excel 2013 (Microsoft, Redmond, WA, USA).Information was organized into sections including authorship, publication year, study design, participant demographics, intervention, comparator, and outcomes.This systematic approach facilitated clarity and analysis, ensuring all relevant details were captured accurately in Table2.