Glossary Of Terms Aap

THE AMERICAN ACADEMY OF PERIODONTOLOGY

Glossary of Periodontal Terms 4th Edition Copyright 200 I by The American Academy of Periodontology Suite 800 737 North Michigan Avenue Chicago, Illinois 60611-2690 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, orotherwise without the express written permission of the publisher. ISBN 0-9264699-3-9 The first two editions of this publication were published under the title Glossary of Periodontic Terms as supplements to the Journal of Periodontology. First edition, January 1977 (Volume 48); second edition, November 1986 (Volume 57). The third edition was published under the title Glossary vf Periodontal Terms in1992.

ACKNOWLEDGMENTS
The fourth edition of the Glossary of Periodontal Terms represents four years of intensive work by many members of the Academy who generously contributed their time and knowledge to its development. This edition incorporates revised definitions of periodontal terms that were introduced at the in Periodontics, as well as at the

1996 World Workshop

1999 InternationalWorkshop for a Classification

of Periodontal Diseases and Conditions. A review of the classification system from the

1999 Workshop has been included as an Appendix to the Glossary.

Particular recognition is given to the members of the Subcommittee to Revise the Glossary of Periodontic Terms (Drs. Robert E. Cohen, Chair; Angelo Mariotti; Michael Rethman; and S. Jerome Zackin) who developedthe revised material.

Under the direction of Dr. Robert E. Cohen, the Committee on Research, Science and Therapy (Drs. David L. Cochran, Chair; Timothy Blieden; Otis J. Bouwsma; Robert E. Cohen; Petros Damoulis; Connie Drisko; James B. Fine; Gary Greenstein; James E. Hinrichs; Martha J. Somerman; Vincent J. Iacono, Board Liaison; and Robert J. Genco, Consultant), as well as Drs. Sigmund Socranskyand Henry Greenwell, served as peer reviewers for this edition of the Glossary.

--------i[A]IABERRANT: Varying or deviating from the usual or
normal course, form, or location.

ABUTMENT: Tooth, root, or implant used to support
and/or anchor a fixed or removable prosthesis.
INTERMEDIA TE A.: Abutment located between

other abutments.

ABFRACTION: Hypothetical tooth surface abrasionin conjunction with occlusal forces; data supporting this term as a discrete clinical entity are not yet available (See Abrasion; Erosion.)

ACANTHOLYSIS: Dissolution of the intercellular
attachments within the prickle cell layer (stratum spinosum) of stratified squamous epithelium. Classically seen in pemphigus vulgaris during vesicle and bulla formation.

ABRASION: Wearing away of asubstance or structure
through an abnormal mechanical process. Examples include gingival and dental abrasions due to incorrect brushing.

ACANTHOSIS: Hyperplasia of the prickle cell layer
(stratum spinosum) of stratified squamous epithelium, resulting in thickened rete ridges or widening of this layer.

ABSCESS: Localized collection of purulent exudate
(pus) in a cavity formed by the disintegrationof tissues.
ACUTE A.: An abscess of relative short duration,

ACATALASIA (Acatalasemia): Deficiency in the
blood and tissues of the enzyme catalase, sometimes resulting in oral ulceration and destruction of alveolar bone.

typically producing pain and local inflammation.
APICAL A.: Inflammatory condition characterized by

ACCRETION: Accumulation on the teeth of foreign
materials such asplaque, materia alba, and calculus.

formation of purulent exudate involving the dental pulp or pulpal remnants and the tissues sun'ounding the apex of a tooth.
CHRONIC A.: I. Abscess of comparatively slow

ACELLULAR: Lacking in cells. ACHE: Any dull, continuous pain. T hought to be the
psychological manifestation of c-fiber (slow, non­ myelinated) nociceptive impulses with origin outside...