GENETICS IN ORTHODONTICS

Genetics is that branch of science which deals with the structure and function of genes in different organisms.

Father of genetics : GREGOR MENDEL

Gene forms the basic unit of inheritance.
A cell-nucleus-nucleolus-chromosome-DNA chains-nucleotides

GENETIC DISORDERS
The conditions that are caused due to disturbances in genes.they are of two types :

HEREDITARY DISORDERS
Those disorders which can be transmitted from one generation to the next

MUTATIONAL DISORDERS
Those disorders which arise in a previously unaffected individual as a result of damage to the germplasm.If it gets transmitted to the next generation ,it becomes a hereditary disorder.

METHODS OF STUDYING ROLE OF GENES :
Twin studies :Twins are compared
Pedigree studies :definite trait is studied in a family tree .Dominant traits are expressed here.
Inbreeding :certain communities practice polygamy and marriage within the family.Recessive traits are expressed here.

DENTOFACIAL DISEASES OF GENETIC ORIGIN :
Micrognathia
Macrognathia
Cleidocranial dysplasia
Cleft lip and palate
Bimaxillary protrusion
Class I ,II ,III malocclusion
Anomalies in shape ,size and number of teeth
Cherubism
Open bite
Deep bite

SIGNIFICANCE OF GENETICS :
To identify the hereditary influence og genes on a particular trait in a family
To know the progosis of orthodontic treatment results
To know exactly why and how malocclusion occurs and its prevelance
To segregate the genetic malocclusions from those caused due to environmental factors
To diagnose ,treat and prevent deformity from occuring in the next generation.

As relapse can be caused by genetic factors and may upset the treatment results.

CLINICAL IMPLICATIONS :
When the information is inadequate or presumptive ,there is a hazard in relying upon the hereditary data.
It has great clinical value in the prediction of growth rate and periodicity
However genetic variations in a family line does not alter the basis of treatment plan.

This field is yet to be developed more.

Some advances include gene mapping ,gene cloning ,gene therapy.