Study focused on people with bruxism, malocclusions by us are not the cause of the dysfunction and CRGP factor levels in the blood. Malocclusion can only aggravate the symptoms of bruxism. Malocclusion are not the direct cause of bruxism

I do accept with Stefan Baron explanation.

hello;

there is a correlation between blood groups and malocculsion . 

one of the early books published was in  1968 by 

Patrick Michael Flannery

Loyola University of Chicago, 1969  the title o f  the book is "The ABO Human Blood Groups and Skeletal Class III Malocclusions"

in a recent article published by 2015

Sharma R, Preethi PN, Nagarathna C, Navin HK. Association of ABO Blood Groups with Malocclusion in

Population of Jaipur, India: A Prospective Study. Int J Sci Stud 2015;2(11):45-51.

they concluded that 

The evaluation of the relationship between blood and

malocclusions revealed that blood groups have association

with malocclusions. Statistical analysis with Chi-square test

revealed that the prevalence of malocclusions is highest in

blood group B, followed by A, O and AB with the least

prevalence. Hence, among all blood groups, blood group B

has the highest prevalence of malocclusion while blood

group AB has the least prevalence of malocclusion.

Further differentiations and other reasons should also

be considered, warranting a more comprehensive study.

More precise research tools and methods are required to

improve knowledge and understanding, which in turn is a

prerequisite to the appreciation of the potential for genetic

and/or environmental manipulation in orthodontic therapy

cheers

prof K.Galil

The ABO blood group system is the first and the most important system defined in 1901 by Karl Landsteiner

(who received a Nobel Prize in 1930 and together with

Weiner; he discovered Rh system in 1940). There are two

main antigens, A and B, in the ABO system, present on cell

membranes or secreted into the plasma and other fluids of the body. The presence or absence of these antigens results

in the four blood groups or blood types: A, B, AB, and O. These antigens are present on the 9th chromosome and

are inherited co-dominantly. Since the malocclusion and

blood groups both are related to genetic components, it

can be hypothesized that blood groups have an association

with malocclusions. In India as well as Western countries,

research has been done to find out the relationship between

ABO blood group and various systemic diseases, and

the results showed that some diseases like dental caries,

salivary gland tumors, chicken pox, malaria, oral cancer, hematological malignancies, ischemic heart disease,

cholera etc. were found to have significant association

with blood groups.