Association between laterality and cleft width in patients with unilateral cleft lip and palate - a systematic review

<title>Abstract</title> <p>Objective To systematically evaluate whether cleft lip laterality is associated with cleft palate width in individuals with unilateral cleft lip and palate. Design Systematic review protocol, registered with PROSPERO (CRD420251006745). Patients Human participants with unilateral cleft lip and palate. Main Outcome Measure The primary outcome was the width of the cleft palate site, measured using clinical or imaging-based methods and compared between left-sided and right-sided unilateral cleft lip and palate. Results Comprehensive searches of MEDLINE (1946 to 5 March 2026) and Embase (1974 to 5 March 2026) identified 143 records. After removal of duplicates and screening, 21 full-text articles were assessed for eligibility. All were excluded because they either did not report cleft palate width, did not stratify cleft width measurements by cleft laterality, or were ineligible publication types such as conference abstracts. Consequently, no studies investigating the association between cleft laterality and cleft palate width were identified. Conclusions No published studies meeting the eligibility criteria were identified. Although both cleft laterality and cleft width are commonly reported, their relationship does not appear to have been directly examined. Greater standardisation in cleft width measurement and reporting may facilitate future investigation of this association.</p>