Volumetric upper airway changes following a new technique for Surgically-Assisted Maxillary Expansion (SAME)

Abstract

Background. Skeletal maxillary constriction (SMC) is one of the common skeletal discrepancies which are associated with alterations in the respiratory function. Today, many surgical techniques are used to expand the maxilla in adult patients with no consensus about the optimal technique. Objectives. The present study aimed to investigate the changes of the upper airway volume resulting from the use of a new, minimally invasive surgically-assisted maxillary expansion (SAME) technique, and compare the results with the conventional SAME technique. Material and methods. A prospective study was conducted between September 2015 and July 2018. A total of 28 adult patients (11 males, 17 females; mean age: 19.1 ±2.7 years) with SMC underwent SAME. The sample was divided according to the applied surgical technique into 2 groups: the conventional osteotomy SAME (CO-SAME) group consisted of 13 patients (18.7 ±2.2 years) and the selective osteotomy SAME (SO-SAME) group consisted of 15 patients (19.4 ±3.2 years). Cone beam computed tomography (CBCT) scans were initially obtained preoperatively (T1) and 3 months post expansion (T2). The upper airway was divided into 2 segments: retropalatal and retroglossal. The volume of each segment and the total airway volume (TAV) were assessed using the OnDemand3D ® software. Results. The total upper airway volume showed a significant increase after both CO-SAME and SO-SAME (1.29 ±0.26 cc and 1.21 ±0.19 cc, respectively), with significant increases in retropalatal and retroglossal airway volumes (RPAV and RGAV) after both CO-SAME and SO-SAME (RPAV-0.73 ±0.10 cc and 0.83 ±0.10 cc, and RGAV-0.56 ±0.23 cc and 0.38 ±0.23 cc, respectively). No significant differences were observed in the maxillary width (MW), TAV or RGAV between the 2 SAME techniques, whereas the increase in RPAV in the SO-SAME group was significantly greater than that of the CO-SAME group. Conclusions. The new, minimally invasive SAME technique was an effective procedure to increase MW and the upper airway volume.

Cone beam computed tomography volumetric airway changes after orthognathic surgery: a systematic review

“…In the four studies on maxillary transverse deficiency, only tooth-borne expansion devices were used, with different expansion protocols. The surgical procedures prior to the expansion varied and included bilateral Le Fort I osteotomy, selective bilateral zygomatic buttress osteotomies (Yazigi et al 55 ), and osteotomy with or without pterygomaxillary disjunction (Rômulo de Medeiros et al 56 ).…”

“…In patients with a maxillary transverse deficiency, surgically assisted expansion of the maxilla showed a tendency towards a volume increase in the different segments of the airway (Supplementary Material Table S2, 3.1.). Significant increases (P < 0.05) in hypopharynx volume were observed after osteotomy of the palate and 0.5 mm expansion on alternate days (Liu et al 54 ), in oropharynx volume after a complete or selective osteotomy followed by 0.9 mm expansion a day (Yazigi et al 55 ), and in nasopharynx volume after Le Fort I osteotomy with or without pterygomaxillary disjunction followed by 0.5 mm expansion a day (Rômulo de Medeiros et al 56 ). The percentage changes varied from + 6% to + 16% and did not appear to be related to the surgery type or the expansion protocol (Fig.…”