Rapid maxillary expansion effects of nasal airway in children with cleft lip and palate using computational fluid dynamics

Abstract

The craniofacial morphology of children with unilateral cleft lip and palate (UCLP) differs from that of children without clefts. 1 Maxillary arch constriction is frequently observed in operated patients with UCLP. 2 Therefore, rapid maxillary expansion (RME) is often required in children with UCLP; in children without clefts, improvements in nasal airway ventilation and dentition expansion may be required. 3 However, improvements in nasal airway ventilation associated with RME in children with UCLP are unclear, particularly in cases involving nasal airway ventilation obstruction. 4 In studies investigating RME in patients with UCLP, the volume 5 and cross-sectional area 6 of the nasal airway reportedly increase. However, nasal septum deviation and the other nasal airway forms are often associated with abnormalities in patients with UCLP. 7 Therefore, it has been unclear whether expansion of nasal Objectives: Rapid maxillary expansion (RME) improves nasal airway ventilation in non-cleft palate children. Children with unilateral cleft lip and palate (UCLP) may have nasal obstruction and experience an increased risk of obstructive sleep apnoea. The effect of RME in UCLP children is unclear. This retrospective study evaluated RMEinduced changes in ventilation parameters in children with UCLP using computational fluid dynamics. Setting and Sample Population: Nineteen patients (10 boys, mean age 10.7 years)who required RME had cone-beam computed tomography images taken before and after RME. Twenty control participants (11 boys, mean age 11.1 years) received regular orthodontic treatment.Methods: Nasal airway ventilation parameters (air pressure, air velocity and airflow rate) were analysed via computational fluid dynamics, and nasal cross-sectional area (CSA) was measured.Results: Maximum pressure, velocity and nasal resistance were significantly reduced by RME in the UCLP group. Air flow rate and CSA on the cleft side significantly were increased by RME in the UCLP group. Conclusions:In children with UCLP, increasing the quantity of airflow and CSA on the cleft side by RME substantially improved nasal ventilation. K E Y W O R D S children, computational fluid dynamics, nasal airway, rapid maxillary expansion, unilateral cleft lip and palate 202 | IWASAKI et Al.width diameter and dentition improves nasal airway ventilation.Recently, computational fluid dynamics (CFD) has been used for evaluation of airway ventilation. 8 Regardless of upper airway shape, CFD reproduces the flow of air and can evaluate air current in the nasal airway alone. Therefore, we speculated that CFD evaluation may be more precise in the evaluation of complicated nasal airways in children with UCLP.The current study investigated improvements in nasal airway ventilation associated with RME in patients with UCLP via CFD in which nasal airway ventilation could be evaluated without being influenced by the complexity of nasal airway shape.

Does Differential Maxillary Expansion Prior to Alveolar Cleft Bone Grafting Affect Nasal Width?

“…Maxillary expansion improves mucociliary clearance and reduces rates of sinusitis in patients with cleft palate. 18,20 Our study supports previous findings that did not identify improvement in alar base symmetry following ABG alone. 21 However, our study showed that maxillary expansion may affect nasal symmetry.…”

“…15,16 Maxillary expansion can increase nasal ventilation, resolve nasal obstruction and reduce nasal pressure with widening at the internal nasal valve. [17][18][19] Trindade et al 3 used acoustic rhinometry to demonstrate patients with unilateral cleft lip and palate had improved nasal air flow following expansion. Maxillary expansion improves mucociliary clearance and reduces rates of sinusitis in patients with cleft palate.…”

“…Maxillary expansion improves mucociliary clearance and reduces rates of sinusitis in patients with cleft palate. 18,20…”

Effects of rapid maxillary expansion on hearing loss and otitis media in cleft palate children

“…Significant improvements after RME in patients with CP/ CLP as observed in our study follow the results available in literature. Sing et al published a randomized controlled trial on 53 patients divided into two groups: patients with no cleft and patients with BCLP, both requiring maxillary expansion for correction of maxillary constriction and arch collapse [26]. The study showed that RME therapy had a statistically significant effect on improvements in hearing and function of the middle ear in both patients with no cleft and with BCLP with normal hearing levels and with mild conductive hearing loss.…”

Rapid Maxillary Expansion Has a Beneficial Effect on the Ventilation in Children With Nasal Septal Deviation: A Computational Fluid Dynamics Study

“…All written informed consents were received from the patients. The sample size was calculated based on an α of 0.05 and a β of 0.2 to detect the difference of 242.66 Pa in maximum pressure between groups, with a 300.22-Pa estimated standard deviation ( 29 ). The power analysis indicated that a sample size of 13 was required.…”