Oral Anatomy Lesson 5

ORAL ANATOMY LESSON 5 PERIODONTIUM – the supporting and investing/surrounding tissues of the teeth

cementum in a coronal manner usually found at the apical portion of the tooth and supports against occlusal stress

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APICAL GROUP OF FIBERS – fibers running from the cementum at the root apex to the wall of the fundus of the bone

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INTERRADICULAR GROUP OF FIBERS – fibers of multi-rooted teeth running from the cementum from the furcation area of the root to the crest of the interradicular bone

ATTACHMENT APPARATUS – supporting tissues INVESTING TISSUES – gingival unit CEMENTUM – contains fibers extending to the periodontal ligaments that attaches to the periodontium PERIODONTAL LIGAMENT – regularly arranged fibrous connective tissues found in the periodontal space and helps form new cementum

ALVEOLAR BONE – the portion of the maxilla and mandible that surround the tooth

PERIODONTAL SPACE – space formed between the cementum and the alveolar bone containing periodontal fibers

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SUPERFICIAL CORTICAL PLATE OF BONE – begins at the crest of the alveolar bone and continues with plate of cortical bone and forms the vestibular and oral aspects (TABLE 1)

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ALVEOLAR BONE PROPER – forms the wall or lining if the sockets (TABLE 2)

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SPONGIOSA/CANCELLOUS BONE – softer part of the bone found between TABLES 1 & 2

FUNCTIONS OF PERIODONTAL LIGAMENT: • SUPPORTIVE/SUSPENSION FUNCTOIN • FORMATIVE OF DEVELOPMENTAL RESORPTIVE • NURTITIVE • SENSORY PERIODONTAL FIBERS – bear the stress of mastication PRINCIPAL BUNDLES OF FIBERS:

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FREE GINGIVAL LIGAMENT – fibers running from the cementum at the neck of the tooth to the connective tissue supporting the gingiva

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TRANSEPTAL/INTERDENTAL FIBERS – fibers running from the cementum of the mesial side of the tooth to the adjacent distal side of the tooth except for the 4 central incisors

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ALVEOLO-DENTAL FIBERS – fibers running from the cementum of the tooth to the alveolar bone

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ALVEOLAR CREST GROOVE – fibers running from the cementum of the cervical third of the tooth to the crest of the alveolar bone

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HORIZONTAL GROUP OF FIBERS – fibers running from the cementum to the wall of the alveolar bone horizontally OBLIQUE GROUP OF FIBERS – fibers running from the alveolar bone to the

DIVISIONS OF THE ALVEOLAR BONE:

GINGIVAL UNIT – the investing structure and the only portion of the periodontium that is visible in the oral cavity SUBDIVISIONS OF GINGIVA:

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FREE GINGIVA – gingival surrounding the neck of the tooth like a collar and fills the interproximal spaces between teeth

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MARGINAL GINGIVA – knife-like edge that extends along the cervical level

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INTERDENTAL GINGIVA – fills up the space between teeth

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ATTACHED GINGIVA – part of gingival that adheres tightly to the bone, possesses interdental folds and stippling

GINGIVAL SULCUS – a space about 1.21.8mm in length that could reach up to 3mm FREE GINGIVAL GROOVE – separates free gingival from attached gingiva INTERDENTAL FOLDS – depression between roots of the teeth

MUCOGINGIVAL JUNCTION – scalloped line that separates attached gingival from alveolar mucosa

- Rosette Go 071008 