Multiple sclerosis, dental caries and fillings: a case-control study.
OBJECTIVE
To investigate the association between multiple sclerosis, dental caries, amalgam fillings, body mercury and lead.


METHODS
Matched case-control study.


METHODS
Leicestershire in the years 1989-1990.


METHODS
Thirty-nine females with multiple sclerosis (of recent onset) were matched with 62 controls for age, sex and general practitioner.


METHODS
Home interview of cases and controls within which there was an assessment of the DMFT index and blood and urine mercury and lead levels.


RESULTS
The odds of being a MS case increased multiplicatively by 1.09 (95% CI 1.00, 1.18) for every additional unit of DMFT index of dental caries. This represents an odds ratio of 1.213 or a 21% increase in risk of MS in relation to dental caries in this population. There was no difference between cases and controls in the number of amalgam fillings or in body mercury or lead levels. There was a significant correlation between body mercury levels and the number of teeth filled with amalgam (controls: r = +0.430, P = 0.006, cases: r = +0.596, P = 0.001).


CONCLUSIONS
There was evidence of excess dental caries among MS cases compared with the controls. This finding supports the strong geographical correlation between the two diseases. A further study of this association is recommended.
McGrother
C W
CW
Department of Epidemiology and Public Health, University of Leicester.
Dugmore
C
C
Phillips
M J
MJ
Raymond
N T
NT
Garrick
P
P
Baird
W O
WO
D000328:Adult; D015982:Bias; D001822:Body Burden; D016022:Case-Control Studies; D004245:DMF Index; D003723:Dental Amalgam / Q000009:adverse effects; D003731:Dental Caries / Q000209:etiology* / Q000378:metabolism; D003793:Dental Restoration, Permanent / Q000009:adverse effects*; D004739:England; D005260:Female; D006801:Humans; D007854:Lead / Q000032:analysis; D008628:Mercury / Q000032:analysis; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications* / Q000378:metabolism; D011897:Random Allocation; D012959:Socioeconomic Factors
D007854:Lead; D003723:Dental Amalgam; D008628:Mercury