Abrasion is when the tooth structure gets worn in the result of some not normal teeth use, such as improper brushing, holding objects between the teeth, etc.
Abscess means some local infection, which is usually caused by such factors as severe tooth decay, trauma and / or periodontal disease. Most common symptoms of abscess are swelling and pain. When it gets ruptured, it is usually accompanied by sudden relief from severe pain. It is also possible to feel some foul taste.
Abutment is the term, which is used to identify the teeth, located on either side of a tooth, which is missing.
Abutment Crown is the kind of an artificial crown, which is used for either the retention or for support of a dental prosthesis.
Acrylic Resin is the plastic, which is applied in dentistry in order to make dentures.
Active Eruption is the phenomenon of tooth appearance from its position in the jaw.
Adhesive Dentistry is the kind of dental restoration, which involves “bonding” of composite resin or porcelain fillings to the natural teeth.
Adjustment is the kind of a modification, which is made upon a dental prosthesis after it is completed and inserted into the mouth cavity.
Air Abrasion is the process, as well as the result of the tooth structure removal by blasting the tooth with air and abrasive, which is quite a modern technology.
Alginate is the kind of an impression material, which is widely applied by dentists for stone models production.
Alveolectomy is the kind of a surgical operation, during which the parts of the alveolar bone are removed.
Alveolar Bone is the bone, located around the root of the tooth. In case if this bone is lost, it is considered to be one of the signs of a severe periodontal disease.   
Alveolar Crest is the name of the highest part of the alveolar bone.
Alveolar Eminence means the outline of the tooth root on the facet part of the bone.
Alveolar Process is the part of either mandible or maxilla, which is situated around the root of a tooth.
Alveolus is the term, which is used to describe the bony socket where the root of the tooth is situated.
Alveoplasty is the kind of a surgical procedure, which is conducted in order to have the supporting bone structures recountered before the complete or partial denture.
Amalgam is also called silver filling. It is the alloy, which is widely used in direct dental restorations, and where mercury is one of the metals; moreover, it occupies the greatest part of the ingredients. Here comes the approximate percentage of the component elements:
Mercury Hg – about 50%;
Silver Ag – about 35%;
Tin Sn – about 13%;
Copper Cu – up to 3%;
Zinc Zn usually less than 1%.