Assessment of respiratory muscle strength and airflow before and after microimplant-assisted rapid palatal expansion

Abstract

Objectives: To assess alterations in respiratory muscle strength and inspiratory and expiratory peak flow, as well as skeletal and dental changes in patients diagnosed with transverse maxillary deficiency before and after microimplant-assisted rapid maxillary expansion (MARPE). Materials and Methods: Twenty patients (13 female and 7 male) were assessed by respiratory tests in three different periods: T0 initial, T1 immediately after expansion, and T2 after 5 months. Tests included: maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP), oral expiratory peak flow, and inspiratory nasal flow. Cone-beam computed tomography measurements were performed in the maxillary arch, nasal cavity, and airway before and immediately after expansion. Results: There was a significant increase in MIP between T0 and T2 and MEP between T0 and T1 (P<.05). Oral and nasal peak flow increased immediately after and 5 months later, especially in patients with initial signs of airway obstruction (P<.05). In addition, after expansion there was a significant enlargement of the nasal cavity, alveolar bone, and interdental widths at the premolar and molar region. Molars tipped buccally (P<.05) but no difference was found in premolar inclination. MARPE increased airway volume significantly. Conclusions: Skeletal changes promoted by MARPE directly affected airway volume, resulting in a significant improvement in muscle strength and nasal and oral peak flow.

Comparison of dimensions and volume of upper airway before and after mini-implant assisted rapid maxillary expansion

“…MARME can improve nasal airflow, leading to better ventilatory function through increased upper airway volume, though the initial purpose of the procedure was to correct a narrow maxilla. 25 So, it could be a therapeutic option for nasal obstruction. 26 However, there was lack of a control group in this study due to ethical issues.…”

Effect of activation protocol on miniscrew-assisted palatal expansion: A systematic review of current evidence

“…Although none of the 11 studies directly investigated the effect of changing the expansion protocol on the skeletal and/or dental outcomes of mini-screw assisted palatal expansion treatment, two different expansion protocols have been identified. The appliance was activated once every other day (0.2 mm) in two studies, [7,38] twice daily (0.5 mm) in eight studies, [40,[47][48][49][50][51][52][53] and the expansion protocol in the remaining study was unreported. [54]…”

“…Seven studies were randomized controlled trials, [7,38,[47][48][49][50][51] two studies were prospective non-randomized controlled trials, [40,52] and two studies were prospective non-randomized uncontrolled trials. [53,54] Only four studies reported sample size calculations. [48,50,51,54] Characteristics of the participants Collectively, the samples comprised adolescents in the 11 trials.…”

“…[40] Significant increase in maxillary width (p=.003) was also evident 3 months after the expansion. [50] In addition, a significant sutural opening was evident immediately after expansion (p<.001) [53] and 6 months after the expansion (p<.001), which accounted for approximately 70% of the total expansion achieved. [48] Regarding the changes in the nasal cavity, one study did not find a significant change (p=.500) in the nasal cavity width immediately post-expansion .…”

“…[48] Regarding the changes in the nasal cavity, one study did not find a significant change (p=.500) in the nasal cavity width immediately post-expansion . [40] On the other hand, a significant increase in the nasal cavity width was found immediately post-expansion (p=.001) [53] , 3 months after the expansion (p=.034) [50] , and 6 months after the expansion (p<.001). [48] The skeletal changes induced by the rapid activation of the miniscrew-assisted palatal expanders were found to significantly improve the nasal airflow immediately post-expansion (p<.05), [47,53] and after 5 months of retention (p<.05).…”