The medical history is considered the cornerstone of safe and effective 
patient management.The main 
parts of the history-taking process well known to practitioners 
are: "Presenting the current (existing) complaint", "the history of the 
current (existing) complaint" and "the current and past medical history". Many patients are surprised to find out how important a medical history 
is for dental care. There are many interrelationships between general 
health and oral health; there are also many interactions of drugs that 
affect dental care. Below are some explanations of why we, as dentists, 
need to know about health conditions. Keep in mind, however, that this 
is by no means a complete list of health conditions or medications that 
affect dental care. Patients should always tell us about any medical 
treatments they are receiving and all medications they are taking. The main parts of a patient history are well-established. It is important 
that practitioners follow a recognized systematic scheme of enquiry to 
minimize the risk of missing important information. All dental 
practitioners are familiar with the main components of the history taking 
process. The first component of a patient history is "Presenting the 
current (existing) complaint".It also includes details of any systemic signs or 
symptoms (such as fever); the success or otherwise of previous
treatments; and previous practitioners who have been consulted 
regarding the same or related condition(s).This includes the following: when the condition/problem 
first started; the overall duration and progression of the condition, 
including whether it is episodic or constant and the nature and timing of 
any symptoms.Presenting the complaint may best be 
expressed in the patient's own words.The information presented can 
then be summarized by the clinician.The second component is the 
"history of the current (existing) complaint".The starting point in the assessment and 
management of any patient depends on good history-taking.A chronological approach 
should be used.