Associations Apnoea Hypopnoea Index (AHI) and Malocclusions in Growing Patients With Maxillary Constriction

The number of apneas and/or hypopneas per hour of recording. It is considered mild OSAS if AHI is between 1 and 5; moderate OSAS if AHI is between 5 and 10; severe OSAS if AHI is greater than 10.

Determined by the intersection of the sellar plane (SN) with the N-point A line; it indicates the anteroposterior position of the maxilla relative to the cranial base. Mean value: 82° ± 2°.

Determined by the intersection of the sellar plane (SN) with the N-point B line; it indicates the anteroposterior position of the mandible relative to the cranial base. Mean value: 80° ± 2°.

Determined by the intersection of the N-point A line with the N-point B line; it indicates the anteroposterior relationship between the maxilla and mandible. The discrepancy identified by this angle defines the skeletal class. Mean value: 2° ± 2°.

Determined by the intersection of the sellar plane (SN) with the mandibular plane (GoGn); it indicates the type of vertical facial growth of the subject. Mean value: 32° ± 5°.

Determined by the intersection of the bipupillary plane (ANS-PNS) with the mandibular plane (GoGn); it indicates the degree of divergence of the mandible relative to the cranial base. Mean value: 20° ± 5°.

Linear distance between SNP and the closest point on the posterior wall of the pharynx along the line connecting SNP-Ba.

Linear distance between SNP and the closest point on the posterior wall of the pharynx measured through the perpendicular line to the connecting S-Ba from the SNP point.

Superior pharyngeal space. Connects the point MPP (midpoint of the pharyngeal side of the velum placed on a line perpendicular to the line connecting SNP-U1) and the point SPAS (point on the posterior wall of the pharynx determined by a perpendicular line to the posterior pharyngeal wall passing through MPP).

Middle pharyngeal space: connects U1 (tip of the soft palate) and U2 (point on the posterior wall of the pharynx determined by a perpendicular line to the posterior pharyngeal wall passing through U1).

Inferior pharyngeal space: distance between point T1 (intersection between the tongue base and the lower margin of the mandible) and point T2 (projection of point T1 on the posterior wall of the pharynx along the parallel to the line Go-Ba).

Connects the points MPP (midpoint of the pharyngeal side of the velum, placed on a line perpendicular to the line connecting SNP with U1) and MPA (point on the oral side of the velum placed on a line perpendicular to the line connecting SNP with U1).

Distance between the tip of the soft palate (U1) and the posterior nasal spine (SNP).

Distance between point H1 (most cranial point of the hyoid bone) and point H2 (projection of point H1 on the perpendicular to the lower margin of the mandible - GoGn).

• Class I molar: The mesiobuccal cusp of the upper first molar contacts the vestibular groove of the lower first molar.
• Class II molar: The mesiobuccal cusp of the upper first molar occludes mesially to the vestibular groove of the lower first molar.
• Class III molar: The mesiobuccal cusp of the upper first molar occludes distally to the vestibular groove of the lower first molar.

The distance, in the sagittal plane, between the upper and lower incisal edges. Mean value: 2 ± 2 mm. If > 2 mm, it is considered "increased"; if < 2 mm, it is considered "reduced".

The distance, in the vertical plane, between the upper and lower incisal edges. Mean value: 2 ± 2 mm. If > 2 mm, it is considered "increased"; if < 2 mm, it is considered "reduced".

The minimum percentage of oxygen-saturated hemoglobin at the time of measurement. SpO2 values are as follows: between 86% and 91% in mild OSAS, between 76% and 85% in moderate OSAS, and less than 75% in severe OSAS.