Genetic Influences on Dental Maturation: A Twin Study

Study Overview
=================
Brief Summary
-----------------
The genetics has been shown as one of the most important factor influencing the growth and development of the dentofacial complex. Dental development, one of the most reliable indicators of chronological age (CA), has been believed to be fundamentally influenced by genetics rather than environmental factors. As twins share genetic variation (100% for monozygotic and 50% for dizygotic twins) and were subjected to the similar environmental factors, the twin studies have been presented useful and effective method to researchers for investigating the influence of heredity on dental development and observing the similarities and differences among twin pairs. Evaluation of dental development is among the most commonly used and reliable method for dental age determination using the morphological parameters of teeth on dental radiographs. Dental maturity, defined as a dental age (DA), is very important in forensic anthropology to identify cases and in dentistry for planning pedodontic and orthodontic treatment, and also determining a child's growth and developmental status. There are many dental age estimation methods which are mostly based on the morphological evaluation of dental growth observed from dental radiographs in children In order to estimate dental age, Demirjian's, Willems' and Nolla's methods were used. All panoramic radiographs were scored by one observer to eliminate the inter-observer error.

Official Title
-----------------
Genetic Influences on Dental Maturation: A Twin Study

Conditions
-----------------
Dental Age Estimation Methods

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: good quality of panoramic radiographs, presence of all permanent mandibular and maxillar teeth except the third molars healthy children with normal eruption of teeth, children with similiar etnic origin and socio-economic status Exclusion Criteria: Children with any syndromes, congenital or developmental anomalies and systemic diseases, Children undergoing or with previous orthodontic treatment history, Children with tooth agenesis, dental trauma history

Ages Eligible for Study
-----------------
Minimum Age: 5 Years
Maximum Age: 13 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Demirjian method<br>According to the Demirjian method, the development of the seven left mandibular permanent teeth (except the third molar) were rated on the eight-stage scale from A to H. Each stage of mineralization was given a score, total dental maturity score was evaluated according to standard tables for boys and girls | |
| Willems method<br>Willems' method was determined using the Demirjian calcification stages but scores were evaluated according to Willems' specific tables | |
| Nolla method<br>In the Nolla method, the development of seven left mandibular and maxillar teeth were defined on 10 stages. If the tooth was between stages an appropriate fraction (0.2, 0.5 or 0.7) was added. The total score was determined according to the tables prepared for girls and boys as recommended by Nolla | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Demirjian method | the development of the seven left mandibular permanent teeth (except the third molar) were rated on the eight-stage scale from A to H. Each stage of mineralization was given a score, total dental maturity score was evaluated according to standard tables for boys and girls | up to 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Willems method | Willems' method was determined using the Demirjian calcification stages but scores were evaluated according to Willems' specific tables | up to 3 years |