iDentistry The Journal September-December 2017 | Page 33

*Dr. Veneet Mehta
**Dr. Jagpreet Singh Sandhu
***Dr. Naveen Bansal
****Dr. Shilpa Gupta
The Journal
“Genetics in relevance to Malocclusion" - A Review
Malocclusions affect individuals worldwide, resulting in compromised function and esthetics.
Understanding the etiological factors contributing to the variation in dentofacial morphology
associated with malocclusions is the key to develop novel treatment approaches. Although etiology
of malocclusion is multifactorial, genes do have influence on this condition, beside their role in
mechanism of tooth movement and unwanted sequel like external root resorption following
orthodontic treatment. Orthodontists may be interested in genetics to help understand why a patient
has a particular occlusion and consideration of genetic factors is an essential element of diagnosis
that underlines virtually all the dentofacial anomalies. This article includes the information on the
association between orthodontics and genetics, an outline of the evidence based impact of heredity
on dentofacial development as a review of the etiological factors of skeletal anomalies from the
genetic point of view.
Introduction
Genetics is the branch of science concerned
with the means and consequences of
transmission and generation of the components
of biological inheritance. Genetics is the study
of genes, heredity, and genetic variation in living
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organisms.
In orthodontics, the effects of genetics on the
etiology of some dento¬facial characteristics
and pathologies have come to light.
Understanding the role of genetics is becoming
necessary in diagnosis and treatment planning.
Since the genetic proof is directly re¬lated to the
diagnosis of familial dentofacial prob¬lems,
modern orthodontists need to be aware of the
basis of the genetic sciences, recent advances
in the genetic researches and their application
in the orthodontic practice. Once the hereditary
fac¬tors are determined and isolated, the
clinician may clearly ascertain and distinguish
the environ¬mental factors and carry out the
treatment plan according to etiology. Therefore,
it is a necessity to clearly outline the association
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between genet¬ics and orthodontics.
Genetics began with the study of how the
characteristics of organisms are passed from
parents to offspring- that is how they are
inherited. Humans have a mere 30,000 genes
rather than the 100,000 predicted earlier.
However, it is also known that by alternative
splicing, 30,000 genes can give rise to greater
than 100,000 proteins. Genetics has revealed
that any two individuals share 99.9% of their
3
DNA sequences.
Malocclusions may be defined as a significant
deviation from what is defined as an ideal or
normal occlusion. Malocclusion is a
manifestation of both environmental and
genetic interaction on the development of the
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craniofacial complex.
Environmental factors known to contribute to
malocclusion include trauma, hormonal
imbalances, muscle dysfunction, poor nutrition,
illness, pituitary gland diseases, mandibular
posture habits, caries experience, premature
loss of primary teeth, history of prolonged
sucking or resting tongue habits, mouth
breathing, enlarged tonsils, atypical
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swallowing, and low socioeconomic status.
* Senior Lecturer, Department of Orthodontics & Dentofacial Orthopaedics, Genesis Institute of Dental Sciences & Research, Ferozepur, Punjab
** Professor, Department of Orthodontics & Dentofacial Orthopaedics, Genesis Institute of Dental Sciences & Research, Ferozepur, Punjab
*** Professor, Department of Orthodontics & Dentofacial Orthopaedics, Genesis Institute of Dental Sciences & Research, Ferozepur, Punjab
**** Reader, Department of Orthodontics & Dentofacial Orthopaedics, Sri Guru Ram Das Institute of Dental Sciences & Research, Amritsar, Punjab
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Vol. 13 No. 3
Sep-Dec 2017