The Effect of Molar Incisor Hypomineralisation on the Stomatognathic System

The Effect of Molar Incisor Hypomineralisation on the Stomatognathic System in Children: A Prospective Study

This study aims to examine whether children with Molar Incisor Hypomineralization (MIH) are more likely to have problems with the jaw joint and chewing muscles. MIH is a dental condition where the enamel of the first molars and incisors is weaker than normal. The researchers performed clinical examinations and ultrasound imaging to evaluate the thickness and elasticity of the chewing muscles. They also used a questionnaire to check for symptoms of temporomandibular disorders (TMD), such as jaw pain, headaches, and joint sounds.

Study Overview

• Status: Completed
• Conditions: Molar Incisor Hypomineralization
• Intervention / Treatment: Diagnostic test: Ultrasound and Shear Wave Elastography

Detailed Description

This prospective clinical study investigates the potential impact of Molar Incisor Hypomineralization (MIH) on the stomatognathic system in children. MIH is a developmental enamel defect that affects the first permanent molars and incisors, resulting in weakened enamel and increased sensitivity. While MIH has been well documented in the context of dental health, its broader functional consequences remain underexplored. A total of 84 children aged 9-14 years participated in this study, including 43 with MIH and 41 healthy controls. The evaluation involved both clinical and ultrasonographic examinations. Temporomandibular disorders (TMD) were assessed using the Fonseca Anamnestic Index and through clinical parameters such as joint sounds, headaches, mandibular deviation/deflection, and mouth opening limitation. Ultrasound imaging, including shear wave elastography, was used to evaluate the thickness and elasticity of the masseter, temporalis, and sternocleidomastoid muscles, as well as the articular disc of the temporomandibular joint.

• Study Type: Observational
• Enrollment (Actual): 84

Contacts and Locations

Study Locations

• Turkey
  • Konyaaltı
    • Antalya, Konyaaltı, Turkey, 07070
      • Akdeniz University Faculty of Dentistry, Department of Pediatric Dentistry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

Children aged 9 to 14 years who visited the pediatric dentistry clinic for routine examinations. The study included both children diagnosed with Molar Incisor Hypomineralization (MIH) and healthy controls without MIH.

Description

Inclusion Criteria:

• Children aged between 9 and 14 years
• Good general health with no systemic disease
• Score of 3 or 4 on the Frankl Behavior Rating Scale
• No parafunctional oral habits (e.g., bruxism)
• No skeletal orthodontic abnormalities
• For the MIH group: presence of at least one first permanent molar diagnosed with MIH
• For the control group: absence of MIH diagnosis

Exclusion Criteria:

• Presence of advanced periodontal disease or tooth mobility
• History of facial trauma or jaw fracture
• Current medication use
• Inability to cooperate during clinical or ultrasonographic examinations
• Any condition that may affect temporomandibular joint structure or function

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
MIH Group; This group includes children aged 9-14 years diagnosed with Molar Incisor Hypomineralization (MIH). Participants in this group underwent clinical and ultrasonographic evaluation to assess temporomandibular joint function and masticatory muscle properties.	Diagnostic test: Ultrasound and Shear Wave Elastography; Non-invasive diagnostic imaging techniques used to assess the stomatognathic system. Ultrasound was performed to measure the thickness of the masseter, temporalis, and sternocleidomastoid muscles, as well as the articular disc of the temporomandibular joint. Shear Wave Elastography was used to evaluate the elasticity (stiffness) of the same muscles and joint structures in kilopascals. All evaluations were conducted at rest, using standardized positioning, and by the same experienced operator.
Control Group; This group includes healthy children aged 9-14 years without a diagnosis of Molar Incisor Hypomineralization (MIH). Participants were evaluated using the same clinical and ultrasonographic procedures as the MIH group.	Diagnostic test: Ultrasound and Shear Wave Elastography; Non-invasive diagnostic imaging techniques used to assess the stomatognathic system. Ultrasound was performed to measure the thickness of the masseter, temporalis, and sternocleidomastoid muscles, as well as the articular disc of the temporomandibular joint. Shear Wave Elastography was used to evaluate the elasticity (stiffness) of the same muscles and joint structures in kilopascals. All evaluations were conducted at rest, using standardized positioning, and by the same experienced operator.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of temporomandibular disorders (TMD) in children with MIH	The presence of TMD was assessed in both the MIH and control groups using the Fonseca Anamnestic Index and clinical examination. TMD diagnosis was based on signs such as joint sounds, deviation/deflection, headaches, and mouth opening limitation.	At the time of enrollment (single clinical visit)
Thickness of masticatory muscles in children with and without MIH	Ultrasound and shear wave elastography were used to evaluate the thickness (in millimeters) of the masseter, temporalis, and sternocleidomastoid muscles bilaterally in both groups. Mean values were calculated and compared.	At the time of enrollment (single clinical visit)
Elasticity of masticatory muscles in children with and without MIH	Ultrasound and shear wave elastography were used to evaluate the elasticity (in kilopascals) of the masseter, temporalis, and sternocleidomastoid muscles bilaterally in both groups. Mean values were calculated and compared.	At the time of enrollment (single clinical visit)

Collaborators and Investigators

• Sponsor: Ozge Gungor

Study record dates

Study Major Dates

• Study Start (Actual): March 10, 2025
• Primary Completion (Actual): March 20, 2025
• Study Completion (Actual): March 20, 2025

Study Registration Dates

• First Submitted: March 28, 2025
• First Submitted That Met QC Criteria: April 22, 2025
• First Posted (Actual): April 30, 2025

Study Record Updates

• Last Update Posted (Actual): April 30, 2025
• Last Update Submitted That Met QC Criteria: April 22, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: ultrasound; temporomandibular disorders; elasticity; masticatory muscle
• Additional Relevant MeSH Terms: Dental Enamel Hypomineralization; Developmental Defects of Enamel; Stomatognathic Diseases; Tooth Diseases; Stomatognathic System Abnormalities; Congenital Abnormalities; Tooth Abnormalities; Molar Hypomineralization; Dental Enamel Hypoplasia
• Other Study ID Numbers: TBAEK-75

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No