Study of Factors of Genetic Susceptibility Associated to Severe Caries Phenotype

Study Overview
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Brief Summary
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Alteration of the post- eruptive enamel microstructure due to a mutation of a gene coding for a matrix protein could increase the susceptibility of the enamel to caries after tooth eruption. To identify in young patients with severe caries incidence, the occurrence of mutations in several candidate genes which result in an alteration of the enamel microstructure that could explain the high caries susceptibility of the patient.

Detailed Description
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Although its prevalence has decreased dramatically in European countries, dental caries remains a burden for the society and especially for certain groups of the population. For example, 80% of the carious lesions are diagnosed in about 20% of the children. For years, the aetiology of this disease has been mainly related to environmental factors but recent data support the possibility of a human genetic contribution. Alteration of the post- eruptive enamel microstructure due to a mutation of a gene coding for a matrix protein could increase the susceptibility of the enamel to caries after tooth eruption. The main objective of this study will be to identify in young patients with severe caries incidence, the occurrence of mutations in several candidate genes which result in an alteration of the enamel microstructure that could explain the high caries susceptibility of the patient. With this aim, we will carry out a case- control multicentre European study on 250 young patients presenting several carious lesions and 160 young adults totally caries free. Patients with systemic or enamel pathologies such as amelogenesis imperfecta will not be included in the study. The study will consist of 2 visits, 1: inclusion and genetic test based on a salivary sample and 2: after 6 months, communication of the genetic test result to the patient and his parents. The main evaluation criteria will be the finding of a mutation on the candidates genes not resulting in an amelogenesis imperfecta phenotype but associated to a severe caries phenotype. If a direct relation between a mutation and a severe caries phenotype was shown, all the classical approaches, prevention protocols and treatments of caries would need to be reconsidered.

Official Title
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Study of Factors of Genetic Susceptibility Associated to Severe Caries Phenotype in Young Patients. First Approach by Systematic Screening of Candidate Genes

Conditions
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Dental Caries

Intervention / Treatment
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* Genetic: mutation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients : presenting at least 3 active carious lesions aged 2 to 16 years old, written informed consent Volunteers : young adults 18 to 30 years old totally caries free Exclusion Criteria: patients with systemic or enamel pathologies such as amelogenesis imperfecta osteogenesis imperfecta hypophosphatemia hypodermal dysplasia syndrome of Prader Willi Fluoroses toxic enamel dysplasia pregnancy or breast-feeding HYPOSIALORRHEA immunodepression status chronicle diseases anorexia or bulimia

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: A<br>250 young patients presenting several carious lesions | Genetic: mutation<br>* a mutation of a gene coding<br>* Other names: a mutation of a gene coding;|
| Placebo Comparator: B<br>160 young adults totally caries free | Genetic: mutation<br>* a mutation of a gene coding<br>* Other names: a mutation of a gene coding;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the finding of a mutation on the candidates genes not resulting in an amelogenesis imperfecta phenotype but associated to a severe caries phenotype |  | baseline, 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| If a direct relation between a mutation and a severe caries phenotype was shown, all the classical approaches, prevention protocols and treatments of caries would need to be reconsidered. |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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caries susceptibility,enamel matrix,candidate genes,mutation