| What are the classification of Periodontal diseases | Gingival lesions
Periodontal lesions
Diagnosis, Prognosis and Treatment plan |
| The term periodontium arises from the Greek word meaning around | peri |
| field of dentistry that focuses on the prevention, diagnosis, and treatment of periodontal diseases (and conditions) and on the placement of dental implants to treat edentulism | Periodontology |
| The various diseases of the periodontium are collectively termed as | periodontal diseases. |
| "tissues investing and supporting the teeth" | periodontium |
| periodontium is composed of 2 hard tissues: | alveolar bone and cementum |
| 2 soft tissues of periodontium | periodontal ligament and supporting gingiva |
| covers the alveolar bone & tooth root to a level just coronal to the cementoenamel junction. | gingiva |
| this type of gingiva is free or unattached | marginal gingiva |
| located between adjacent teeth | Interdental papillae |
| The most apical point of the marginal gingival scallop is called | gingival zenith. |
| The most coronal portion of gingiva.
well-adapted to tooth surface but not attached to it. | Marginal(free) gingiva |
| firmly bound to the underlying tooth & alveolar bone. | Attached Gingiva |
| portion of free gingiva located in inter-proximal space created by contact between two adjacent teeth. | Interdental gingiva (papilla) |
| The shape of interdental papilla depends on: | the presence or absence of a contact point between the adjacent teeth,
the distance between the contact point & the osseous crest
Presence or absence of some degree of recession. |
| Facial & lingual papillae are connected together by a valley-like depression called _____ made up from non keratinized epithelium & represents the most frequent site for initiation of disease process. | "Col" |
| a -V- shaped shallow crevice around the tooth, bounded by the tooth surface in one side & the epithelial lining the marginal gingiva on the other side. | gingival sulcus |
| Clinical normal gingival sulcus depth: | 0-3 mm |
| Gingival Pocket- | periodontal disease |
| There is a fluid secreted from gingival C.T into the sulcus through the thin sulcular wall termed as | gingival fluid. |
| Components of sulcular fluid | 1. Cellular elements
2. Electrolytes
3.Organic compounds
4.Metabolic & bacterial products
5.Enzymes |
| Functions of Gingival (Crevicular) Fluid | ■ Its flow washes out irritants & prevent bacterial penetration.
■ Its plasma proteins improve epithelial adhesion to the teeth.
■ Has antibacterial effect upon many oral microorganisms.
■ Has defense mechanism by its immunoglobulin contents.
■ Essential growth factor for many microorganisms |
| Cells of the gingival epithelium | Keratinocytes |
| non keratinocytes: | Melanocytes
Langerhans cells
Merkel cells |
| keratinized stratified squamous epithelium arranged in 4 layers: | Stratum basale, Basal cell layer (The deepest)
Stratum Spinosum, prickle cell laye
Stratum granulosum, granular cell layer
Stratum corneum, Keratinized cell layer |
| lines the gingival sulcus facing the tooth extending from coronal limit of junctional epitht. the crest of gingival margin | Sulcular Epithelium |
| the tissue that joins the tooth on one side and to sulcular epith& C.T on the otherIt forms the base of the sulcus | Junctional Epithelium (Epithelial attachment) |
| Attachment of the junctional epith. to the tooth is reinforced by the | gingival fibers |
| the junctional epith. and the gingival fibers are considered a functional unit, referred to as the | dentogingival unit. |
| Three zones in junctional epith. have been described | apical, coronal and middle |
| Lamina propria consist of: | ■mainly Collagen fibers (60%)
■ Cells mainly fibroblasts(5%)
■Intercellular ground substance
■Blood vessels, lymphatic, Nerves |
| Primary gingival fibers: | Circular fibers:
Dentogingival fibers:
Alveologingival fibers:
Dentoperiosteal fibers:
Transseptal fibers: |
| Secondary Gingival Fibers | Semicircular fibers (SCF): from mesial surface of a tooth to distal surface of same tooth in a half circle
Transgingival fibers (TGF): these fibers traversing from CEJ to free gingiva of adjacent tooth
Intergingival fibers (IGF): extend along facial and lingual marginal gingiva from tooth to tooth. |
| They are the predominant cells, they are functioning to:
1.Synthesize and secrete collagen fibers, elastin, non-collagenous proteins, glycoprotein
2. Renewal of collagen fibers and other constituents
3. Regulation of gingival wound healing. | Fibroblast |
| nerve supply of the gingiva | maxillary and mandibular branches of trigeminal nerve. |
| Average width of PDL space is about | 0.25mm |
| The most important elements of PDL are the | principal fibers type I collagen |
| considered remnants of the Hertwig root sheath, which disintegrates during root development. | The epithelial rests of Malassez |
| Immune system cells: | neutrophils,lymphocytes, macrophages, mast cells & cosinophils. |
| Functions of PDL | 1. Provision of a soft-tissue "casing" to protect the vessels & nerves from injury by mechanical forces
2. Transmission of occlusal forces to the bone
3. Attachment of the teeth to the bone
4. Maintenance of the gingival tissues in their proper relationship to the teeth
5. Resistance to the impact of occlusal forces (shock absorption |
| Application of large forces results in _____ of PDL & alveolar bone | necrosis |
| Calcified avascular tissue that forms the outer covering of the root of the teeth & provide attachment to the periodontal ligament | Cementum |
| Has no vascular or nerve connection. | Cementum |
| Functions of cementum | provide anchorage, maintaining occlusal relationships |
| occurs in Paget's disease | hypercementosis |
| are globular calcified masses adherent to or detached from the root surface. | Cementicles |
| Fusion of the cementum & alveolar bone with obliteration of PDL. | Ankylosis |
| T or F.
Cementum is similar to bone but has no nerves. Therefore it is non-sensitive to pain | true |
| 2/3 inorganic matter mainly calcium + phosphate in the form of hydroxyapatite crystals
1/3 organic matrix mainly collagen type I | Extracellular matrix |
| the tissue lining the internal bone cavities is called | endosteum |
| flattened cells, in a plane parallel to the gingival surface | stratum granulosum |
| associated with kratin formation 1 micrometer in diameter, round in shape and appear in the cytoplasm of the cell | keratohyaline granules |
| stratum cornea retains | pyknotic nuclei |
| cohesion between cells is provided by numerous structures called | desmosomes |
| sensory in nature- respond to touch | tactile perceptors |
| forms the bulk of lamina propria, provides tensile strength to the gingival tissue | collagen type I |
| the periodontal ligament space has the shape of an _______ | hourglass |
| the width of periodontal ligament is approximately | 0.25mm (range 0.2-0.4 mm) |
| principal fibers of the periodontal ligament follow a____ course when sectioned longitudinally | wavy |
| formative cells | fibroblast
osteoblasts
cementoblasts |
| resorptive cells | fibroblasts
osteoclasts
cementoclasts |
| epithelial cells | remnants of hertwig epithelial root sheath |
| immune system cells | neutrophils, lymphocytes, macrophages, mast cells, eosinophils |
| extend interproximally over the alveolar bone crest and are embedded in the cementum of adjacent teeth | transseptal fibers |
| extend obliquely from cementum just beneath junctional epithelium to alveolar crest; prevents extrusion of tooth | alveolar crest group |
| extend at right angles to the long axis of the tooth from cementum to alveolar bone; resists tipping forces; prevents lateral movements | horizontal group |
| largest group, extend from cementum in a coronal direction to bone; bear brunt if vertical masticatory stresses and transform them into tension on alveolar bone | oblique group |
| radiate in an irregular manner from cementum to bone at apical region of socket;resist tipping forces and luxation; protects blood vessels and nerves | apical group |
| dan out from cementum to tooth in furcation areas of multirooted teeth' resist tipping, torquing and luxation | interradicular group |
| elastin fibers : | oxytalan and elaunin |
| small collagen fibers associated with principal fibers | indifferent fiber plexus |
| the palatal gingiva of maxilla drains to: | deep cervical lymph nodes |
| third molars and mandibular incisors drain to: | submandibular lymph nodes |
| the third molars drain to the: | jugulodigastric lymph nodes |
| the mandibular incisors drain to the: | submental lymph nodes |
| a theory that states "force applied to crown cause principal fibers first unfold and straighten and then transmit forces to the alveolar bone- an elastic deformation of bony socket" | tensional theory |
| theory that states "displacement of the tooth is largely controlled by fluid movements with fibers have only a secondary role" | visco elastic theory |
| theory that states "PDL behaves like a thixotrophic material a collagenous gel and that fibers are only artefacts" | thixotrophic theory |
| often site of periapical granuloma which proliferates to produce a cyst common pathological lesion | periodontal ligament in periapical area |
