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

Abstract

Objectives To evaluate changes in dimensions and volume of upper airway before and after mini-implant assisted rapid maxillary expansion (MARME) and observe correlations between changes of upper airway and vertical skeletal pattern in young adults. Materials and Methods In this retrospective study, 22 patients (mean age, 22.6 ± 4.5 years; 4 male 18 female) with transverse discrepancy underwent MARME. Cone beam computed tomography was taken before and 3 months after expansion. Vertical and horizontal dimensions and volume of the nasal cavity, nasopharyngeal, retropalatal, retroglossal and hypopharyngeal airway were compared before and after MARME. Correlations between changed volume and dimensions were explored, as well as the vertical skeletal pattern. Results Nasal osseous width, maxillary width, volume of the nasal cavity and nasopharynx increased significantly (P < .05). Enlarged nasopharyngeal volume correlated with increased nasal width at the PNS plane (P < .05). There were no correlations between expanded volume and maxillary width. No measurements except nasal cavity volume had a correlation with Sum angle. Increased maxillary width correlated negatively with hard palate thickness (P < .05). Conclusions (1) MARME caused an increase in volume of the nasal cavity and nasopharynx, with expansion of nasal osseous width and maxillary width. (2) Enlarged nasal width at the PNS plane contributed to the increase in nasopharynx volume. Enlarged maxillary width showed no direct relation with increased volume. (3) In this study, it was unclear about the association between changes of the upper airway and vertical skeletal pattern because of complex structures. (4) Palate thickness affected skeletal expansion of the maxilla in MARME.

Efficacy of Miniscrew-Assisted Rapid Palatal Expansion (MARPE) in late adolescents and adults: a systematic review and meta-analysis

“…A variety of different measurements was used across these studies (see: Table 3a ). The mean skeletal expansion ranged from 1.11 mm to 4.5 mm and was statistically significant in all five articles ( 28 , 29 , 31 , 32 , 34 ) where the p-value was calculated. One study differentiated between a midpalatal suture separation group and a non-separation group and reported results for both groups separately and combined ( 35 ).…”

“…One article was excluded to avoid result overestimation, as the authors failed to reply to an e-mail regarding the outcome data ( 27 ). A remaining total of nine articles ( 28–36 ), two prospective ( 29 , 30 ) and seven retrospective observational studies ( 28 , 31–36 ) met the inclusion criteria of this review. A Cohen’s Kappa analysis was performed for assessment of inter-rater reliability, which proved to be good ( κ = 0.82).…”

“…The ROBINS-I tool was used for the risk of bias assessment of all the included studies, all of which were observational studies (see: Figures 2 & 3 ). One study ( 30 ) showed a moderate risk of bias and seven studies ( 28 , 29 , 31–35 ) had a serious risk of bias, mainly because of bias due to confounding, selection of participants and measurement of outcomes. One study ( 36 ) had a critical risk of bias and was thus excluded from further analysis according to the ROBINS-I tool ( 24 ), bringing the final number of included studies down to eight.…”

“…All eight studies ( 28–35 ) reported the success rate of the MARPE treatment, which ranged from 80.65% to 100% (see: Table 2 ). Three studies reported a success rate of 100% ( 29 , 31 , 33 ).…”

“…Skeletal transverse maxillary expansion was reported in seven articles ( 28 , 29 , 31–35 ). A variety of different measurements was used across these studies (see: Table 3a ).…”