abscess – severe and/or chronic localized inflammation in the gum tissue or at the tooth root that usually presents with infection, swelling, pain, and pus, and can cause damage to surrounding teeth and bone if left untreated

abutment – a natural tooth or dental implant that is used to support a fixed or removable dental prosthesis

acid etching – preparation of tooth enamel or dentin surface by the use of an acidic chemical to ensure successful bonding

acrylic resin – compound that may be used to fabricate dental prosthetics, such as denture teeth and crowns

ADA – American Dental Association, an organization of professional dentists within the United States, commonly known for providing public dental health education

adhesion – part of the bonding process, characterized by chemical or physical agents connecting two or more surfaces with or without the use of adhesive

adhesive – any substance that causes two or more surfaces to maintain connection with one another for an indefinite period of time

air abrasion – the use of a tool that blasts air and abrasive material at a tooth to remove small amounts of tooth structure

alloy/amalgam – compound made up of two or more elements and containing properties not found in the individual elements

alveolar – part of the jaw bone where teeth are anchored

anesthesia (local) – medication used to block pain in one area for treatment

anesthesia (general) – medication used to induce partial or complete unconsciousness during treatment

anterior – refers to teeth or tissues in the front part of the mouth

ANUG – Acute Necrotizing Ulcerative Gingivitis, a condition characterized by small ulcers in the gums and aggravated by stress or smoking

apex – tip of the tooth root

apicoectomy – surgical amputation of a tooth root to treat a dead tooth

appliance – oral device such as braces, mouth guards, or retainers

arch – curved structure of upper or lower teeth

archwire – metal wire used in braces to guide teeth into proper alignment

arthrogram – diagnostic x-ray involving injection of contrast dye into joint to view the bone structures

artificial crown – prosthetic tooth restoration that covers or replaces a tooth, may attach to partial tooth or dental implant

attrition – natural wear causing loss of structure

augmentation – procedure that treats a deficiency of soft tissue or bone structure

avulsion/evulsion – removal of tooth from socket due to trauma