Evaluating the Respiratory Muscle Function in Patients with Cleft Lip and Palate: Maximal Inspiratory and Expiratory Pressure Analysis

Objective To evaluate the respiratory muscle strength in patients with cleft lip and palate (CLP) and correlate with airway dimensions. Design Cross-sectional. Setting The study was conducted at a Sri Ramachandra Dental College and hospital in India. Participants Adult patients were divided into three groups with eleven participants in each group. Group 1 comprised patients with CLP who had undergone alveolar bone grafting (ABG) but without maxillary expansion. Group 2 comprised patients with CLP, who had undergone ABG and maxillary expansion. Group 3 patients formed the control group which comprised non-CLP, Class I skeletal base patients. Main Outcome Spirometric tests were performed, and maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured. Results Mean MIP values for group 1, group 2, and group 3 were 2.5 ± 1.2 kPa, 5.6 ± 1.9 kPa, and 6.0 ± 1.9 kPa while MEP values were 4.1 ± 1.4 kPa, 6.2 ± 1.4 kPa, and 6.6 ± 1.9 kPa, respectively. Patients who had undergone ABG, but not maxillary expansion (Group 1) had statistically significant lesser MIP and MEP values ( P <.001*). The mean peak expiratory flow and forced expiratory volume (FEV1) values were also decreased in group 1 but were not statistically significant ( P >.05). Pharyngeal volume also decreased in patients with CLP. ( P <.05). A positive, statistically significant correlation was found between nasopharyngeal volume (NPV) and MIP (R = 0.53) and NPV and MEP (R = 0.44) ( P <.05*). Conclusion This research provides conclusive evidence that patients with CLP have respiratory muscle weakness. This may result in functional deficits. The interdisciplinary team should plan the treatment accordingly.