Clinical trial NCT00541060: Study of Factors of Genetic Susceptibility Associated to Severe Caries Phenotype
Official title: Study of Factors of Genetic Susceptibility Associated to Severe Caries Phenotype in Young Patients. First Approach by Systematic Screening of Candidate Genes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Dental Caries
Keywords: caries susceptibility,enamel matrix,candidate genes,mutation
Lead sponsor: Assistance Publique - Hôpitaux de Paris
Sponsor class: OTHER
First posted: 2007-10-08
Enrollment: 390
Sex: ALL
Minimum age (years): 2
Maximum age (years): 30
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: 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: 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.

Eligibility criteria: 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

Primary outcomes:
measure: the finding of a mutation on the candidates genes not resulting in an amelogenesis imperfecta phenotype but associated to a severe caries phenotype
timeFrame: baseline, 6 months
Secondary outcomes:
measure: 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.
timeFrame: 6 months
Other outcomes:
Locations:
city: Paris
country: France
facility: Hopital Bretonneau
Study officials:
affiliation: Assistance Publique - Hôpitaux de Paris
name: Catherine Miller, MCU-PH
role: STUDY_DIRECTOR
References: