DISEASES OF THE HARD TISSUE
Section I. GENERAL INFORMATION ON ORAL PATHOLOGY
a. Pathology is the study of disease, especially of the structural and functional
changes in tissues and organs that cause or are caused by disease. Oral pathology is
that branch of pathology concerned with diseases of the oral cavity. Microbiology is the
study of microorganisms, including bacteria, fungi, and viruses. Disease is a particular
destructive process in an organism, usually with a specific cause and with characteristic
signs and symptoms. A sign is objective evidence of disease that is detectable by the
health care provider; for example, redness or bleeding. A symptom is subjective
evidence of disease--in other words, what a patient tells the health care provider.
Examples of symptoms would be pain and weakness. The word asymptomatic refers to
a disease exhibiting no symptoms.
b. Terminology of a descriptive nature is used to define aspects of a pathological
process. Local (localized) means that the disease is restricted to a part or small area of
the body. Generalized means the disease affects all parts of the body or covers a large
area (many organ systems). Incipient refers to a disease or disorder that is just
beginning. Severe refers to an intense distress of prolonged duration caused by the
disease process. Acute relates to a sudden onset of symptoms, generally of short
duration. Chronic refers to a prolonged disease process, with symptoms generally of a
As you study this subcourse, you may wish to refer to Subcourse MD0501,
Dental Anatomy and Physiology.
INFLAMMATION OF TISSUES
When a tissue is injured or irritated by mechanical, chemical, thermal, or bacterial
agents, it becomes inflamed. Inflammation is the reaction of a tissue to an injurious
agent. The body does not always overcome the attack and so disease persists. For
example, the irritation produced by dental caries may result in inflammation of the pulp.
This pulpal inflammation is called pulpitis. (The suffix "itis" indicates that inflammation
exists). In every case, the inflammatory condition results from some form of irritation
and, in order to restore normal function to the tissues, the cause must be eliminated.
The function of inflammation is to activate all the defenses of the body and to bring them
to the site of the injury with the purpose of overwhelming the source of the injury or