Healthy Periodontium
Transcription
Healthy Periodontium
Healthy Periodontium Periodontal Morphology – Healthy Periodontium Alveolar Bone Root Cementum Periodontal Ligament Gingiva The Periodontium Gingiva Periodontal Ligament Root Cementum Alveolar Bone (Alveolar Process) Gingiva Alveolar mucosa Attached gingiva Free gingiva Interdental gingiva Gingiva Tissue covering the cervical portions of the teeth and the alveolar processes of the jaws Composed of thin outer layer of epithelium and an underlying core of connective tissue Provides a tissue seal around the cervical portions of the crowns Clinical Anatomy of the Gingiva Clinical Anatomy of the Gingiva Attached gingiva Free gingiva Free gingival groove Gingival margin Gingival sulcus (gingival crevice) Interdental gingiva Papilla/Papillae Col Alveolar mucosa Mucogingival junction Clinical Anatomy of the Gingiva Free gingiva Gingival margin Gingival sulcus (gingival crevice) Attached gingiva Mucogingival junction Alveolar mucosa Clinical Anatomy of the Gingiva Interdental gingiva Facial papilla Lingual papilla Clinical Anatomy of the Gingiva Col Proximal contact area Col Proximal contact area Clinical Anatomy of the Gingiva Free Gingiva Unattached portion of the gingiva that surrounds the tooth in the region of the cemento-enamel junction (CEJ). Located coronal to (above) the CEJ. It surrounds the tooth in a turtleneck or cufflike manner Also known as the unattached gingiva or the marginal gingiva Clinical Anatomy of the Gingiva Free gingiva characteristics Free gingiva Fits closely around the tooth but is not directly attached to it May be stretched away from the tooth surface with a periodontal probe Forms soft tissue wall of gingival sulcus Meets the tooth in a thin rounded edge called the gingival margin Gingival margin follows the contours of the teeth, creating a scalloped (wavy) outline around them Clinical Anatomy of the Gingiva Gingival Sulcus The space between the free gingiva and the tooth surface V-shaped, shallow space around the tooth Junctional epithelium – forms base of sulcus Clinical Anatomy of the Gingiva This periodontal probe is divided into 3 millimeter colored segments Periodontal probe being used to measure depth of the sulcus Gingival Sulcus The depth is 1-3 mm for a clinically normal gingival sulcus The depth is measured using a periodontal probe Dental floss being used to clean the gingival sulcus and the tooth Clinical Anatomy of the Gingiva Gingival Sulcus Probing the sulcus depth interproximally is best accomplished by angling the probe so its tip is located at the center of the root A = incorrect technique for interproximal probing B = correct probing technique C = incorrect probing technique Clinical Anatomy of the Gingiva Junctional Epithelium Specialized type of epithelium that attaches to the tooth surface Located at the base of the gingival sulcus Clinical Anatomy of the Gingiva Attached gingiva Gingiva that is tightly connected to the cementum on the cervicalthird of the root and to the periosteum (connective tissue cover) of the alveolar bone Lies between the free gingiva and the alveolar mucosa Clinical Anatomy of the Gingiva Attached gingiva functions Allows the gingival tissue to withstand mechanical forces Mastication, Speaking, Toothbrushing Prevents free gingiva from being pulled away from the tooth when tension is applied to the alveolar mucosa. Clinical Anatomy of the Gingiva Interdental gingiva The portion of the gingiva that fills the area between two adjacent teeth apical to the contact area Clinical Anatomy of the Gingiva Papilla The interdental (or interproximal) gingiva consists of two interdental papillae one facial papilla one lingual papilla Papilla (singular) Papillae (plural) Clinical Anatomy of the Gingiva Col Valley-like depression in the interdental gingiva Lies directly apical to the contact area The col is not present if the adjacent teeth are not in contact or if the gingiva has receded Clinical Anatomy of the Gingiva Left = incorrect vertical technique for probing interproximal craters Right = correct angled position of the probe to reach the depth of an interproximal crater Clinical Anatomy of the Gingiva Alveolar Mucosa Movable tissue loosely attached to underlying bone Nonkeratinized Thin, smooth and shiny epithelium Dark red in color Underlying vessels may be seen through the epithelium. Alveloar mucosa also covers the vestibule and floor of the mouth and becomes the buccal and labial mucosa Clinical Anatomy of the Gingiva Mucogingival junction The clinically visible boundary where the pink attached gingiva meets the red, shiny alveolar mucosa Microscopic Anatomy of the Gingival Epithelium Gingiva Oral epithelium (OE) Sulcular epithelium (SE) Junctional epithelium (JE) Gingival connective tissue Microscopic Anatomy of the Gingiva Sulcular epithelium Oral epithelium Gingival Epithelium Oral epithelium – faces Junctional oral cavity on outer epithelium surface of the free gingiva and attached gingiva Sulcular epithelium – lines the gingival sulcus Junctional epithelium – provides contact between the gingiva and the tooth. Often referred to as the epithelial attachment Microscopic Anatomy of the Gingiva OE = oral epithelium SE = sulcular epithelium JE = junctional epithelium CEJ = cementoenamel junction Gingival connective tissue – underlies the epithelium and provides support through an organization of collagen fibers Periodontal Ligament Periodontal Ligament (PDL) Layer of soft connective tissue Covers the root of the tooth Attaches the root to the bone of the tooth socket Composed mainly of fiber bundles Fibers attach on one side to the root cementum Fibers attach on the other side to the alveolar bone of the tooth socket. Periodontal Ligament Functions of the Periodontal Ligament Support - suspends and maintains the tooth in its socket Sensory - provides sensory feeling to the tooth; pressure and pain sensations Nutritive - provides nutrients to the cementum and bone Formative - builds and maintains cementum and the alveolar bone of the tooth socket Resorptive - can remodel the alveolar bone in response to pressure Example: pressure applied during orthodontic treatment (braces) Root Cementum Root Cementum Thin layer of hard, mineralized connective tissue Covers tooth from the cementoenamel junction to, and around, apical foramen Overlies and is attached to the dentin of the root Periodontal ligament attaches to the cementum Root Cementum Root Cementum Light yellow in color With normal gingival position, it is not visible but can be seen when gingival recession is present Gingival recession is present on the facial surface due to trauma from overly vigorous toothbrushing Alveolar Bone Alveola r proce Basal ss bone Alveolar Bone (also called alveolar process) The bony portion of the maxilla or mandible that extends occlusal to the basal bone and surrounds and supports the roots of the teeth The existence of the alveolar bone is dependent on the presence of teeth When teeth are extracted, in time, the alveolar bone resorbs so only basal bone remains If teeth do not erupt, the alveolar bone does not develop Alveolar Bone Function of Alveolar Bone Forms the bony sockets that provide support and protection for the roots of the teeth one Alveolar B Alveolar Bone Anatomical Areas of the Alveolar Bone: Alveolar crest Interproximal bone Interradicular bone (bone between the roots of the same tooth) Anatomical Areas of the Alveolar Bone Alveolar Crest Most coronal portion of the alveolar process Located 1-2 mm apical to the CEJs of the teeth (in health) Viewed from the facial aspect, alveolar crest meets the teeth in a scalloped (wavy) line that follows the contours of the CEJs Anatomical Areas of the Alveolar Bone Interproximal Bone The area of bone that lies between the proximal surfaces of two adjacent teeth Also known as interdental septum Anatomical Areas of the Alveolar Bone Crestal Contour of Interproximal Bone The contour of the crest of the interproximal bone is a good indicator of periodontal health In posterior sextants, the contour of the interproximal crest is parallel to an imaginary line drawn between the CEJs of the adjacent teeth Anatomical Areas of the Alveolar Bone Radiograph showing horizontal contour of the interproximal bone in the maxilla due to good tooth alignment Radiograph showing angular crest due to tilted mandibular second molar Horizontal Crest Contour Crest has horizontal contour when the CEJs of the adjacent teeth are at the same level Angular Crest Contour Crest has vertical contour when one of the adjacent teeth is tilted or erupted to different heights Anatomical Areas of the Alveolar Bone jaw Interradicular Bone (multirooted teeth only) Bone between the roots of a multirooted tooth Components of the Alveolar Bone jaw Cortical bone Supporting bone Alveolar bone proper Alveolus Periosteum Components of the Alveolar Bone Cortical bone Forms the hard, outside wall of the mandible and maxilla on the facial and lingual aspects Buccal cortical bone Thin in the incisor, canine, and premolar regions Thicker in the molar regions Components of the Alveolar Bone Defects of cortical bone Fenestration Window-like defect in the cortical bone Results in an isolated area of the root that is not covered by bone Dehiscence Cleft-like defect in the cortical bone Includes bone margin Components of the Alveolar Bone Supporting Bone Lattice-like bone Fills interior portion of the alveolar process Between the cortical bone and the alveolar bone proper Also known as spongy bone, cancellous bone Components of the Alveolar Bone Alveolar bone proper Thin layer of bone that lines each alveolus In radiographs, the alveolar bone proper is identified as the lamina dura Contains numerous holes that allow the blood vessels from the cancellous bone to connect with the vessels of the periodontal ligament space Components of the Alveolar Bone Alveolus The alveolus is the bony socket in the alveolar bone It is the cavity in the alveolar bone that houses the root(s) of a tooth Alveolus (singular) Alveoli (plural) Components of the Alveolar Bone Periosteum The thin layer of connective tissue that covers bone and is overlaid by the soft tissue (gingiva or alveolar mucosa)