Upper Airways Cephalometric Measures Compared to Skeletal Class and Divergence

A Retrospective Cephalometric Study on Upper Airways Changes Compared to Skeletal Angle Class and Divergence: a Retrospective Observational Study

The aim of the present study is to investigate the baseline upper airways dimensions in adult patients belonging to all skeletal classes

Study Overview

• Status: Completed
• Conditions: Skeletal Malocclusion
• Intervention / Treatment: Diagnostic test: Cephalometric analysis

Detailed Description

Lateral cephalometric radiographs of adult orthodontic patients referring for orthodontic consultation at the Unit of Orthodontics and Pediatric Dentistry, Section of Dentistry, Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, 27100 Pavia, Italy, will be collected for the study according to the inclusion criteria.

For each lateral cephalometric radiograph, a cephalometric tracing will be performed with DeltaDent software (version 2.2.1, Outside Format, Spino d'Adda, Italy). Riedel's ANB angle [Riedel 1952] has been adopted to determine patients' skeletal class. Steiner's SN^GoGn angle [Steiner 1953] will be used to evaluate skeletal divergence. Biprotrusion will be assessed for SNA > 84° and SNB > 82°, while biretrusion for SNA < 80° and SNB < 78°.

Sample size calculation was performed with "soft palate length" as primary outcome. Considering alpha = 0.05 and power = 95%, an expected mean value of 31.05 with a standard deviation of 4.16 was hypothesized, with an expected mean difference of 3.34 [Sprenger et al. 2017], therefore 40 patients per group were required.

Statistical analysis will be conducted with R® software (version 3.1.3 R Development Core Team, R Foundation for Statistical Computing, Wein, Austria). For each cephalometric measure belonging to the three skeletal classes, descriptive statistics (mean and standard deviation) will be calculated. Appropriate statistical tests will be used to assess data normality and multiple comparisons. Linear regressions will be performed between upper airways diameters and SNA, SNB, ANB, SN^GoGn, ANSPNS^GoGn, PT, PL, sex and age.

• Study Type: Observational
• Enrollment (Actual): 120

Contacts and Locations

Study Locations

• Italy
  • Lombardy
    • Pavia, Lombardy, Italy, 27100
      • Unit of Orthodontics and Pediatric Dentistry - Section of Dentistry - Department of Clinical, Surgical, Diagnostic and Pediatrics - University of Pavia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients referring to the Unit of Orthodontics and Pediatric Dentistry for orthodontic consultation.

Description

Inclusion Criteria:

• Patients with permanent dentition
• Caucasian patients
• Patients with one lateral cephalometric digital radiograph executed in Natural Head Position (patients were asked to keep the teeth in contact and the lips relaxed).

Exclusion Criteria:

• maxillo-facial traumas
• nasopharyngeal pathologies
• craniofacial dysmorphisms
• orthognatic surgery
• radiographs not performed in Natural Head Position
• unsuitable radiographs

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Skeletal Class I patients; Patients from this group present 0° < ANB < 4° on the cephalometric tracing.	Diagnostic test: Cephalometric analysis; Cephalometric analysis will be performed evaluating upper airways landmarks.
Skeletal Class II patients; Patients from this group present ANB > 4° on the cephalometric tracing.	Diagnostic test: Cephalometric analysis; Cephalometric analysis will be performed evaluating upper airways landmarks.
Skeletal Class III patients; Patients from this group present ANB < 0° on the cephalometric tracing.	Diagnostic test: Cephalometric analysis; Cephalometric analysis will be performed evaluating upper airways landmarks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
NL (nasopharynx length)	Distance between Ad1 and PNS	Baseline
PD (nasopharynx depth)	Line parallel to bispinal plane and connecting PNS and the posterior margin of pharynx	Baseline
SPAS (Superior Pharyngeal Airway Space)	From the half of the posterior wall of soft palate (MMP) perpendicularly to the closest point on the posterior of the posterior wall of the pharynx	Baseline
MAS (Mean Airway Space)	U1-U2 distance	Baseline
PAS min (Pharyngeal Airway Space minimum)	T1-T2 distance along Go-B parallel line	Baseline
IAS (Inferior Airway Space)	From the superior margin of the epiglottis (Ph1) to the closest perpendicular point on the posterior wall of the pharynx	Baseline
LPW (Lateral Pharyngeal Wall)	Distance between epiglottic vallecula (Va1) and the posterior wall of pharynx perpendicular to Va1	Baseline
PT	Soft palate thickness	Baseline
PL	Soft palate length	Baseline
MPH (Mandibular Plane - Hyoid bone)	Distance from the most anterior and superior point of the hyoid bone (H1) perpendicular to mandibular plane	Baseline

Collaborators and Investigators

• Sponsor: Andrea Scribante

Study record dates

Study Major Dates

• Study Start (Actual): February 12, 2023
• Primary Completion (Actual): March 20, 2023
• Study Completion (Actual): March 26, 2023

Study Registration Dates

• First Submitted: February 2, 2023
• First Submitted That Met QC Criteria: February 10, 2023
• First Posted (Actual): February 13, 2023

Study Record Updates

• Last Update Posted (Actual): March 28, 2023
• Last Update Submitted That Met QC Criteria: March 26, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Keywords: Upper airways dimensions; Skeletal Class; Skeletal Divergency
• Additional Relevant MeSH Terms: Stomatognathic Diseases; Tooth Diseases; Malocclusion
• Other Study ID Numbers: 2023-AIRWAYSCLASS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Data will be available upon motivated request to the Principal Investigator.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No