Orofacial Muscle Pressure and Maxillary Transverse Development

Summary

Study Title: Investigation of the Effects of Tongue, Lip, and Cheek Pressures on the Development of Upper Jaw Narrowness

Introduction and Hypothesis The structure of our face and the alignment of our teeth are influenced not only by our genetics but also by the surrounding soft tissues, such as the lips, cheeks, and tongue. These muscles exert constant pressure on our teeth and jawbones. According to the "Equilibrium Theory," teeth stay in their proper positions when the inward pressure from the lips and cheeks is balanced by the outward pressure from the tongue.

The hypothesis of this study is that individuals with a narrow upper jaw (maxillary constriction) may have different muscle pressure patterns compared to those with normal jaw widths. We believe that identifying these pressure differences will help dentists and orthodontists better understand why jaw narrowness occurs and how to achieve more stable results after treatment.

What is Being Measured? To measure these delicate pressures, we use a specialized, high-tech device called the Iowa Oral Performance Instrument (IOPI). This device uses a small, air-filled balloon (bulb) that the patient presses with their tongue or lips. It allows us to measure muscle strength and endurance in "kilopascals" (a unit of pressure) without any pain or discomfort.

Study Procedure

This study will involve patients aged 12 to 25 who are seeking orthodontic treatment at Van Yüzüncü Yıl University. We will divide the participants into two groups:

Patients with a narrow upper jaw.

Patients with a normal upper jaw width (the control group).

Before any orthodontic braces are applied, we will measure:

Tongue Pressure: How hard the tongue can push against the roof of the mouth.

Lip Pressure: The strength of the upper and lower lips.

Cheek (Buccal) Pressure: The pressure exerted by the cheeks during rest and function.

Importance of the Study While many studies have looked at how these muscles affect the forward or backward position of teeth, there is very little research on how they affect the width of the jaw. By comparing these two groups, we hope to discover whether "weak" or "overactive" muscles contribute to a narrow palate. This information could lead to new treatment methods that focus not just on moving teeth, but also on training the oral muscles to ensure that the beautiful smiles created by orthodontists last a lifetime.

Conditions

• Maxillary Transversal Deficiency (Maxillary Constriction) and Perioral Muscle Pressures (Tongue, Lip, and Cheek)

Interventions

DIAGNOSTIC_TEST

Orolingual Manometry using IOPI Pro Deluxe Kit

A standardized measurement of perioral muscle pressures (tongue, lip, and cheek) will be conducted using the Iowa Oral Performance Instrument (IOPI). The procedure involves placing a disposable, air-filled bulb at specific intraoral locations (e.g., retro-incisal for tongue pressure, buccal vestibule for cheek pressure). Participants are instructed to exert their maximum isometric force against the bulb for a specific duration. Each measurement is performed three times with 30-second rest intervals, and the peak pressure is recorded in kilopascals (kPa). This procedure is purely diagnostic and non-invasive, performed once for each participant before the initiation of any orthodontic intervention.

Sponsors & Collaborators

• Yuzuncu Yil University

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

12 Years

Max Age

25 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-05-01

Primary Completion

2026-07-01

Completion

2026-12-01

Countries

• Turkey (Türkiye)

Study Locations