Correlation Between Colour and Hypersensitivity of First Permanent Molars With Molar Incisor Hypomineralisation (MIH)

Molar-Incisor Hypomineralisation (MIH): Correlation Between Colour of the Defect and Hypersensitivity in Young First Permanent Molars

Cheese molars (MIH: molar incisor hypomineralisation) can be recognized not only by their colour abnormalities but also by their hypersensitivity. Clinical management of these teeth may become challenging by the chronic hypersensitivity, which makes various steps of a treatment, such as pain control or light curing of any type of composite restorations, difficult or even impossible, despite profound local anesthesia. Hypersensitivity can be detected by the clinician based on the patient's statements or reaction. On the other hand, colours and structural abnormalities can be easily assessed by visual inspection. The aim of this study is to determine the relationship between hypersensitivity and the colour of the enamel defect on young first permanent molars. A correlation between colour of the defect and hypersensitivity could enable early prognosis leading to preventive measures in order to delay, amplify or even avoid the onset of the symptoms. Children diagnosed with MIH on their first permanent molars of different severity are matched to children with sound molars. They are identified by the annual school dental check-up and are invited to take part in the study. The children will be invited to the university dental clinic via letter for the first appointment. Upon parental consent, the teeth will be photographed and scanned as well as investigated for hypersensitivity through a gentle air blast.

Study Overview

• Status: Recruiting
• Conditions: Molar Incisor Hypomineralisation

Detailed Description

Aim of the study is the correlation between the colour of the enamel defect and hypersensitivity in young first permanent molars. Children diagnosed with MIH from the onset of eruption of the first permanent molar, matched by age with children with sound first permanent molars are investigated. Children screened by the school dental services of Basel-Stadt as well children attending the department of children and adolescents (KJZM) of the University Centre for Dental Medicine in Basel (UZB), diagnosed with MIH on one or more first permanent molars receive a letter of information- invitation to be seen in the department of children and adolescents (KJZM).

The control group consists of fit and healthy children 5-8 years old, who attend the department of children and adolescents (KJZM-UZB) for their regular dental check-ups.

A written informed consent will be obtained from the parents/legal guardians. Colour definition The exact colour determination of the teeth will be carried out as follows: The teeth are photographed with a canon SLR camera. (Canon EOS 80D; Canon inc. Japan), a ringflash (Macro Ring Lite MR-14EXII; Canon) and a macro lens (EF-S 60mm 1:2:8 USM; Canon) will be used. All camera settings (1/250, aperture F20, iso-sensitivity 100 and a fixed white balance AWBW (white priority), flash intensity +/-0) and the tooth-lens distances (25 cm) are standardized by one operator (VM, SR). A colour reference card (grey card) is photographed together with the tooth of interest in order to identify and equalize the colour deviations. The resulting photo will be uploaded to the Photoshop Adobe 6 and the values of the RGB code (0-255 for each of the three colours) will be determined. The tolerance range is set to +/- 10. If the 3 colours are within the tolerance, the photo can be used to determine the colour of the tooth to be examined. The darkest part of the tooth is then determined. The degree of darkness is indicated by a number between zero and one hundred, where L=100 is white and L=0 is black (Wiedrichs et al. 2023).

The sensitivity of the teeth will be assessed by using the Schiff Cold air Sensitivity Scale (Schiff et al 1994). Teeth will be dried by an air blast defined at 5 bar. Prior to the examination patient will be introduced to the procedure by "tell-show-do" method. Based on the patient's reaction, the sensitivity to the air shock is divided into:

0 no reaction to the stimulus

1. reaction, but continuing with the stimulus possible
2. reaction, moving, demanding termination
3. painful, immediate abandonment of procedure In addition to the sensitivity, assessed by the main investigator (VM or SR), the Wong-Baker Faces Pain Rating Scale (Wong-Baker FACES Foundation 2022) will be applied. The scale consists of six faces representing different expressions of pain, ranging from a laughing face with no pain (score 0) to a crying face with severe pain (score 10). Each face has a numerical score from 0 to 10 indicating pain intensity. Children will be asked to select the face that best describes their current pain experience.

Each appointment lasts a maximum of 30 minutes. In addition to the Schiff-Cold-Air-Scale-Test, hypersensitivity is also determined using the Face-Pain-Scale.

• Study Type: Observational
• Enrollment (Estimated): 45

Contacts and Locations

• Study Contact: Name: Eirini Stratigaki, Dr.med.dent; Phone Number: +41 61 555 33 89; Email: eirini.stratigaki@unibas.ch
• Study Contact Backup: Name: Sibylle Haas; Phone Number: +41 61 555 33 65; Email: sibylle.haas@uzb.ch

Study Locations

• Switzerland
  • Canton of Basel-City
    • Basel, Canton of Basel-City, Switzerland, 4058
      • Recruiting
      • University Centre for Dental Medicine
      • Contact: Sibylle Haas; Phone Number: +41 61 555 33 65; Email: sibylle.haas@uzb.ch
      • Contact: Eirini Stratigaki, Dr.med.dent.; Phone Number: +41 61 555 33 89; Email: eirini.stratigaki@unibas.ch
      • Sub-Investigator: Vivienne Mazenauer, med.dent

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Children screened by the school dental services of Basel-Stadt as well children attending the department of children and adolescents (KJZM) of the University Centre for Dental Medicine in Basel (UZB), diagnosed with MIH on one or more first permanent molars will receive a letter of information- invitation to be seen in the department of children and adolescents (KJZM).

The control group will consist of fit and healthy children 5-8 years old, who attend the department of children and adolescents (KJZM-UZB) for their regular dental check-ups.

Description

MIH Study Group

Inclusion Criteria:

• Children between 5 to 8 years with MIH molars with or without hypersensitivity according to the MIH-TN Index (Bekes et al 2016)
• Children with first molars in occlusion
• Children fit and healthy

Exclusion Criteria:

• MIH first permanent molars that have already received any kind of dental treatment
• Children diagnosed with HSPM (hypomineralised second primary molars)
• Children older than 8 years - Children younger than 5 years
• Children with any cranio-facial and/or other developmental dental defects
• Children diagnosed with parafunctions (attrition/ erosion)
• Children and/or parents who did not consent to the study
• Children with MIH teeth that show clinically visible enamel loss during the eruption
• Children without the first molars in occlusion

Non- MIH Control Group

Inclusion Criteria:

• Children between 5 to 8 years with no clinically affected molars
• Children fit and healthy

Exclusion Criteria:

• Children who have already received any kind of dental treatment on their permanent or primary teeth
• Children diagnosed with MIH or any other disease of the teeth
• Children older than 8 years
• Children younger than 5 years
• Children with any cranio-facial and/or other developmental dental defects
• Children diagnosed with parafunctions (attrition/ erosion)
• Children and/or parents who did not consent to the study

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
MIH Group; Children 5 to 8 yrs old diagnosed with Molar Incisor Hypomineralisation on one or more first permanent molars
Non-MIH (Healthy) Group; Children 5 to 8 yrs old with no signs of Molar Incisor Hypomineralisation on one or more first permanent molars

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Colour of the defect	A colour reference card (grey card) is photographed together with the tooth of interest in order to identify and equalize the colour deviations. The resulting photo will be uploaded to the Adobe Photoshop 6. and the values of the RGB code (0-255 for each of the three colours) will be determined. The tolerance range is set to +/- 10. If the 3 colours are within the tolerance, the photo can be used to determine the colour of the tooth to be examined. The darkest part of the tooth is then determined. The degree of darkness is indicated by a number between zero and one hundred, where L=100 is white and L=0 is black (Wiedrichs et al. 2023).	Baseline investigation at first appointment
Hypersensitivity	The sensitivity of the teeth will be assessed by using the Schiff Cold air Sensitivity Scale (Schiff et al 1994). Teeth will be dried by an air blast defined at 5 bar. Prior to the examination patient will be introduced to the procedure by "tell-show-do" method. Based on the patient's reaction, the sensitivity to the air shock is divided into: 0 no reaction to the stimulus; reaction, but continuing with the stimulus possible; reaction, moving, demanding termination; painful, immediate abandonment of procedure In addition to the sensitivity, assessed by the main investigator (VM or SR), the Wong-Baker Faces Pain Rating Scale (Wong-Baker FACES Foundation 2022) will be applied. The scale consists of six faces representing different expressions of pain, ranging from a laughing face with no pain (score 0) to a crying face with severe pain (score 10). Each face has a numerical score from 0 to 10 indicating pain intensity. Children will be asked to select the face that best describes t	Baseline appointment

Collaborators and Investigators

• Sponsor: University of Basel
• Investigators: Study Director: Carlalberta Verna, Professor Dr.med.dent., University of Basel; Principal Investigator: Eirini Stratigaki, Dr.med.dent, University of Basel

Study record dates

Study Major Dates

• Study Start (Actual): January 9, 2026
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): October 31, 2026

Study Registration Dates

• First Submitted: July 21, 2026
• First Submitted That Met QC Criteria: July 21, 2026
• First Posted (Actual): July 27, 2026

Study Record Updates

• Last Update Posted (Actual): July 27, 2026
• Last Update Submitted That Met QC Criteria: July 21, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Hypersensitivity; MIH; colour of defect
• Additional Relevant MeSH Terms: Dental Enamel Hypomineralization; Developmental Defects of Enamel; Stomatognathic Diseases; Immune System Diseases; Tooth Diseases; Stomatognathic System Abnormalities; Congenital Abnormalities; Tooth Abnormalities; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Molar Hypomineralization; Hypersensitivity
• Other Study ID Numbers: MIH UZB 2024-02230

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: This has not been decided yet

Drug and device information, study documents

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