recent public health reports have identified northwestern ontario and thunder bay for increased risk of coronary heart disease among several cohorts. the present study investigated the relationship between myocardial infarction and periodontal disease in individuals' aged 55 and over. as well, a biological mechanism, which may be an indicator to coronary heart disease and periodontal disease, was measured among the sample population. both myocardial infarction and periodontal disease can result from inflammation of the micro-vascular blood supply that provides oxygenated blood to the tissue of the heart and gums, respectively. several research studies have reported a link between periodontal disease and coronary heart disease/myocardial infarction. furthermore, the suggested association between myocardial infarction and periodontal disease is based on the simultaneous occurrence of the two events and therefore the potential co-incidence may have a measurable probability. in both coronary heart disease and periodontal disease clinicians may observe an increased concentration of c-reactive protein and/or fibrinogen. not only are these proteins prevalent in individuals who are diagnosed with coronary heart disease, myocardial infarction and periodontal disease, but also the presence of these proteins may further exacerbate the inflammatory condition and thereby, degrade the integrity of the micro-vascular system. thus suggesting that the underlying causal mechanism for both myocardial infarction and periodontal disease might be the presence of c-reactive protein and/or fibrinogen. participants were identified and recruited from a population of cardiac patients in the region of thunder bay. all participants have cardiac disease confirmed clinically and objectively by symptoms, stress test, cardiolite and/or angiogram. at least half of the selected participants had experienced a myocardial infarction within the past twelve months (february 2001 to february 2002) as verified by the cardiologist. the periodontal evaluation included, a count of the number of teeth present, a measure of gingivitis, the average probing depth (six sites- medial and distal), and the individual's bana hydrolase (will be referred to as bana from this point) test score. the composite of the measures was thus considered representative of the individual's periodontal disease. forty-two people were involved in this study as research participants. the results indicated that negative relationship was apparent between the risk of having a myocardial infarction and the measure of periodontal disease. however, a relationship was found between the risk of having a myocardial infarction and the blood measures of c-reactive protein and fibrinogen. this research has provided a baseline for future research, and many suggestions and recommendations have come from the results.