Midterm

Structure of the periodontium (attachment apparatus) and location

  • trigeminal nerve

  • tissue surrounding teeth and attaches to the jawbone

    • gingiva, cementum, PDL, and alveolar bone

  • gingiva: tissue that covers the cervical portion of the teeth and alveolar processes

  • cementum: a thin layer of mineralized tissue that covers the root of the tooth

  • PDL: fibers that surround the tooth; attach to the socket on one side and the cementum of the root on the other side

  • Alveolar bone: bone that surrounds the root of the tooth, forms pockets that support the roots

Function of PDL

  • suspends and maintains the tooth in the socket

Function of gingival fibers (supragingival fibers)

  • network of rope-like collagen fiber bundles in the gingival connective tissue.

  • Located coronal to the crest of the alveolar bone and form soft tissue

Anatomical areas of the gingiva are missing when you see open spaces apical to the contact areas

  • interdental gingiva

periodontal health

  • Two types:

    • clinical gingival health on intact periodontium

    • clinical gingival health on a reduced periodontium

  • absence of bleeding on probing, erythema, edema, attachment loss, and alveolar bone loss

gingivitis

  • Definition: Inflammatory response resulting from the biofilm accumulation located below the gingival margin

  • two types: dental biofilm-induced or non-dental biofilm-induced

  • dental biofilm-induced gingivitis:

    • dental biofilm alone

    • mediated by systemic or local risk factors

    • drug-influenced gingival enlargement

  • Non-dental biofilm-induced gingival disease

    • genetic/developmental disorders

    • specific infections

    • inflammatory and immune conditions

    • reactive processes

    • neoplasm

    • endocrine, nutritional, and metabolic disease

    • traumatic lesions

    • gingival pigmentation

  • gingival health: <10%, localized gingivitis: 10%-30%, and generalized gingivitis: >30%

  • JE at CEJ; 3mm or greater; reversible

Periodontitis

  • results in progressive irreversible destruction of the periodontal ligament and supporting alveolar bone

  • JE on cementum; >4mm of pocket depth

  • characterization: apical migration of JE, loss of connective tissue attachment, and loss of alveolar bone

Staple Periodontitis

  • periodontal health on the periodontium with pre-existing loss of connective tissue and alveolar bone that is attributed to periodontitis but that has been successfully treated and is currently stable.

Junctional epithelium

  • specialized epithelium that forms the base of the sulcus and joins the gingiva to the tooth surface

  • functions: attachment, barrier, and host defense

Alveolar bone proper/cribriform plate/lamina dura

  • A radiopaque layer of bone that lines the alveolar socket

Structures to know:

  • mucogingival junction

    • clinically visible boundary where the pink attached gingiva meets the red, shiny alveolar mucosa

    • clinically visible (demarcations)

  • free gingival groove

    • A shallow linear depression that separates free and attached gingiva

    • rarely visible to the naked eye (demarcations)

  • alveolar crest

    • coronal-most portion of the alveolar process

    • in health, located 1 to 2 mm apical to CEJ

  • spongy and compact bone

    • Compact (cortical) bone forms the hard outer wall of the mandible and maxilla; it surrounds the alveolar bone proper

    • Cancellous (spongy) bone fills the inner portion of the alveolar process (between cortical bone and alveolar bone proper)

  • alveolar bone proper (cribriform plate)

    • thin layer of bone that lines the socket and surrounds the root

    • has foramina that allow blood vessels from cancellous bone to connect with the vessels of the PDL space

  • interdental col

    • valley-like depression in the portion of the interdental gingiva that lies directly apical to the contact area of 2 adjacent teeth and contacts the facial and lingual papillae

    • absent if adjacent teeth are not in contact

  • attached gingiva (where is it thinnest?)

    • continuous with the free gingiva is tightly bound to cementum on the cervical-third of the root and periosteum of the alveolar bone

    • lies between the free gingiva and the alveolar mucosa

    • thinnest in the premolar region

  • desmosomes

    • create cell-to-cell connections

    • found in the gingival epithelium

  • hemi-desmosome

    • create cell-to-basal lamina connection

    • found in the gingival epithelium

  • osteoblast

    • bone-formers that produce the bone matrix consisting of collagen fibers and protein fibers

  • osteoclasts

    • bone consumers; cells that remove the minerals and organic matrix of the alveolar bone

  • Sharpey’s fibers

    • Calcified terminal ends of PDL embedded in cementum and alveolar bone

    • attach when cementum and bone are forming

  • pathogenesis

    • sequence of the events that occur during the development of a disease or abnormal condition

  • anastomosis

    • vessels of the periodontium join together to supply blood

  • horizontal bone loss

    • most common in periodontitis

    • fairly even reduction in the height of the alveolar bone

  • vertical bone loss (angular bone loss)

    • less common

    • uneven reduction in the height of the alveolar bone

  • infrabony pockets

    • occurs when vertical bone loss is present

    • classified into infra-bony defects or osseous defects

    • JE is located apical to the crest of the alveolar bone

  • suprabony pockets

    • occurs when horizontal bone loss is present

    • base of the periodontal pocket is coronal to the alveolar crest

    • JE is located coronal to the crest of the alveolar bone

  • gingival pocket (pseudo-pockets)

    • deepening of the gingival sulcus as a result of swelling or enlargement of the gingival tissue

    • caused by: detachment of the coronal portion of JE and/or increased tissue size due to swelling

  • periodontal pocket

    • pathologic deepening of the gingival sulcus

    • results from either apical migration of the JE, destruction of the periodontal ligament fibers, or destruction of the alveolar bone

  • pseudo-pocket

    • no apical migration of the JE, coronal portion of the JE detaches from the tooth that results in increase probing depth

  • staging (severity) and grading (speed)

    • grade A: 1/3

    • grade B: 2/3 (most common)

    • grade C: 1/3

marginal gingivitis vs diffuse gingivitis

  • marginal gingivitis → affect gingival margin and papilla

  • diffuse gingivitis → extend to include the gingival margin, papilla, and attached gingiva

refractory vs recurrent periodontitis

  • refractory periodontitis

    • exhibits continuing attachment loss despite receiving periodontal therapy, self-care, and maintenance visits

  • recurrent periodontitis

    • return of destructive periodontitis that had been previously arrested by therapy; common

keratinization

  • process by which surface epithelial cells become stronger and waterproof

  • keratinized epithelial cells

    • no nuclei

    • form a tough, resistant layer on skin

  • nonkeratinized epithelial cells

    • nuclei

    • acts as a cushion

stippling

  • on the attached and interdental gingiva

  • present in 40% of pts with healthy gingiva

pyogenic granuloma

  • noncancerous, raised tumor in your skin or mucous membrane

  • associated with pregnancy-associated gingivitis

3 major forms of periodontitis in the current AAP Classifications

  • necrotizing periodontal disease

  • periodontitis

  • periodontitis as a manifestation of systemic disease

Vitamin C

  • also Ascorbic Acid; deficiencies cause ascorbic-acid-deficiency-gingivitis and scurvy

warning signs of periodontitis

  • accumulation of plaque biofilm and calculus

  • redness (erythema) and swelling (edema)

  • gingival bleeding

  • suppuration (pus)

  • periodontal pockets

  • clinical attachment loss and tooth mobility

common mucogingival deformity

  • gingival recession

What % of patients over 65 have at least one area of gingival recession

  • 88%

Miller gingival recession classification

  • Class I

    • marginal tissue that does not extend to MGJ

  • Class II

    • marginal tissue recession that extends to or beyond MGJ with no periodontal loss in the interdental area

  • Class III

    • marginal tissue recession that extends to or beyond MGJ with interdental bone or soft-tissue loss and/or mal-the positioning of teeth

  • Class IV

    • marginal tissue recession that extends beyond MGJ with severe loss of interdental bone to level corresponding to most apical extent of marginal tissue recession

Parts of an implant

  • implant body (implant fixture)

    • made of titanium (zirconia as an alternative) or a titanium alloy

    • acts as “root.”

  • abutment

    • connects the prosthesis to the implant body

    • titanium or zirconia

  • prosthetic crown or prosthesis

Diagnosis choices: peri-implant health, peri-implant mucositis, peri-implant gingivitis, and peri-implantitis

  • peri-implant health

    • absence of erythema, bleeding on probing, swelling, and suppuration

    • probing depths may be deeper at the site

  • peri-implant mucositis

    • visual signs of soft-tissue inflammation, presence of bleeding and/or suppuration upon probing, increased probing depth, absence of bone loss

  • peri-implant gingivitis

    • plaque biofilm-induced inflammation of soft tissue with no loss of supporting bone localized in mucosal tissues surrounding dental implant

  • peri-implantitis

    • plaque biofilm-induced inflammation and progressive loss of alveolar bone

    • inflammation, bleeding and/or suppuration upon probing, increased probing depth, progressive bone loss, radiographic evidence of bone level >3mm, and/or probing depth >6mm

uses of dental implants

  • replaces individual teeth or multiple teeth by supporting fixed bridges or removable dentures

  • indicator of implant failure → mobility

How often should radiographs be taken of dental implants

  • At least once a year

Radiopaque or Radiolucent

  • PDL

    • radiolucent

  • lamina dura

    • radiopaque

  • alveolar bone proper

    • radiopaque

  • amalgam restorations

    • radiopaque

  • marrow spaces in spongy (cancellous bones) 

    • radiolucent

  • enamel

    • radiopaque

  • cementum

    • radiopaque

  • dentin

    • radiopaque

  • pulp

    • radiolucent

  • periapical lesions

    • radiolucent

  • sialoliths

    • radiopaque

normal probing depths

  • 1–3 mm deep when healthy

The height of the Alveolar Crest is in health

  • 1-2mm apical to CEJ

Does epithelium have its own blood supply?

  • NO

  • WHY there’s 1-2mm between CEJ and alveolar bone; 1-2mm represents supra-crestal tissue attachment (STA) or biologic width, and supra-crestal attached tissue (SAT)