ABP Periodontology key terms

The soft connective tissue layer between the tooth root cementum and the alveolar bone socket. It anchors the tooth, absorbs occlusal forces, and contains fibers, vessels, and nerve endings.

A thin mineralized tissue covering the tooth root surface. It provides insertion for periodontal ligament fibers and thickens over time, especially near the apex and in response to function.

The portion of jaw bone that forms and supports the tooth sockets. It develops with the tooth and resorbs after extraction, and its height and thickness determine periodontal support.

The shallow space between the free gingival margin and the tooth surface. In health it is lined by sulcular epithelium and contains gingival crevicular fluid.

A nonkeratinized epithelial band that attaches the gingiva to the tooth surface at the base of the sulcus. It forms the epithelial seal and migrates apically as attachment is lost.

The distance in millimeters from the gingival margin to the base of the probeable sulcus or pocket. It is measured at several sites per tooth and does not by itself indicate attachment loss.

The distance from a fixed reference point, usually the cementoenamel junction, to the base of the periodontal pocket. It estimates true support loss, unlike probing depth alone.

Destruction of the periodontal ligament and cementum attachment to bone, measured clinically as apical migration of the junctional epithelium. It is the defining feature of periodontitis.

Apical displacement of the gingival margin relative to the cementoenamel junction, exposing root surface. It may occur with or without attachment loss and can cause sensitivity or esthetic concern.

A pathologically deepened gingival sulcus. It may be a true pocket with apical migration of the epithelial attachment or a pseudopocket caused by gingival enlargement without attachment loss.

The visible line where attached gingiva meets alveolar mucosa. It separates keratinized masticatory mucosa from nonkeratinized lining mucosa and serves as a landmark for graft and flap planning.

Keratinized gingiva extending from the base of the sulcus to the mucogingival junction. It is firmly bound to underlying periosteum and bone and contributes to gingival stability during function.

Fluid that seeps from gingival tissues into the sulcus. Its volume and composition change with inflammation, and it carries cells, enzymes, and mediators used in periodontal research.

A structured community of bacteria embedded in a self-produced matrix on tooth and implant surfaces. Its accumulation initiates gingivitis and drives periodontitis when not disrupted.

Mineralized dental plaque that forms on teeth and restorations. It is covered by viable biofilm and cannot be removed by brushing, so scaling is required.

Reversible inflammation of the gingiva caused by plaque biofilm, with redness, swelling, and bleeding on probing but no attachment loss. It is treated by biofilm removal and improved hygiene.

A chronic inflammatory disease of the supporting tissues caused by dysbiotic plaque biofilm, producing attachment loss and progressive bone destruction. It is classified by stage and grade.

Bleeding elicited when a periodontal probe is gently passed along the sulcus. It indicates active inflammation and, when absent at repeated visits, suggests pocket stability.

The current classification framework for periodontitis. Stage describes severity and complexity of management, while grade estimates rate of progression based on history and risk factors.

A vertical bone defect in which the base of the pocket lies apical to the adjacent alveolar crest. Its morphology, especially depth and number of walls, affects regenerative treatment outcomes.

Loss of periodontal attachment and bone into the space between the roots of a multirooted tooth. It is graded by extent and complicates hygiene, prognosis, and treatment planning.

Instrumentation that removes plaque, calculus, and contaminated cementum from crown and root surfaces, usually under local anesthesia in deep pockets. It is the foundation of nonsurgical periodontal therapy.

A surgical technique using a barrier membrane to exclude gingival epithelium and connective tissue from a defect, allowing slower periodontal ligament and bone cells to repopulate the space.

Particulate or block material placed into a periodontal or surgical defect to support new bone formation. It may be autogenous, allograft, xenograft, or alloplast and acts as scaffold or osteoinductive agent.

A graft of epithelium and connective tissue harvested, usually from the palate, and placed to increase attached keratinized tissue. It is useful for root coverage and gingival augmentation.

Ongoing supportive care after active periodontal therapy, including reassessment, biofilm removal, and reinforcement of home care at planned intervals. It reduces the risk of disease recurrence.

Systematic evaluation of patient factors such as smoking, diabetes, plaque control, and history of disease that influence the likelihood of periodontal progression or treatment failure.

Direct structural and functional connection between living bone and the surface of a load-bearing implant, without an intervening soft tissue layer. It is the biological basis of implant success.

The ability of an implant to resist movement, derived from mechanical engagement initially and from bone apposition over time. It is assessed clinically and by resonance frequency analysis.

The application of occlusal force to an implant through its restoration. Timing may be immediate, early, or conventional, depending on primary stability and bone quality.

Reversible inflammation limited to the soft tissues around an implant, with bleeding on probing and no progressive bone loss. Treatment focuses on biofilm control and decontamination.

Inflammation of the tissues around an implant accompanied by progressive loss of supporting bone. It is diagnosed by bleeding, pocket depth, and radiographic bone change.

Regular professional and home care after implant placement to control biofilm and monitor tissue health. It includes probing, radiographs, and removal of prosthesis when indicated.

A surgical procedure that elevates the maxillary sinus membrane to create space for bone graft and allow implant placement in the posterior maxilla. It may be performed via a lateral window or crestal approach.

Mechanical engagement of an implant with bone at the time of placement, before any biological bonding. It depends on bone density, implant design, and surgical technique.

A noninvasive method that measures implant stability by vibrating the implant and analyzing its frequency response. Higher values generally indicate greater stability.

A surgical technique using a barrier membrane with or without graft material to exclude soft tissue and allow bone to fill a defect around or before implant placement.