Periodontology

The terminal edge of gingiva which forms a 1-2mm wide cuff around the neck of the tooth

• Marginal gingiva

• Attached gingiva

• Interdental gingiva

• Attached gingiva and center of interdental papilla

Answer explanation

Marginal gingiva is also called free gingiva as it is not attached to the underlying periosteum of alveolar bone.

It is demarcated from attached gingiva by the free gingival groove positioned at the level of CEJ.

It forms the tissue wall of the gingival sulcus, which is a shallow groove between tooth and normal gingiva.

Stippling is seen in

• Marginal gingiva

• Attached gingiva

• Interdental gingiva

• Attached gingiva and center of interdental papilla

Answer explanation

The pitted surface texture giving an orange peel appearance on the attached gingiva and center of interdental papilla is called a stippling.

Width of attached gingiva varies from 0-9mm, with the greatest width in the incisor region and least width in the premolar area.

The mucogingival junction is located between the

• Free gingiva and attached gingiva

• Free gingiva and tooth

• Base of the sulcus and alveolar mucosa

• Attached gingiva and alveolar mucosa

Answer explanation

Mucogingival junction is the interface between the apically located nonkeratinized alveolar mucosa and the coronally located parakeratinized attached gingiva

Col is found in

• Marginal gingiva

• Attached gingiva

• Interdental gingiva

• Alveolar mucosa

Answer explanation

Col is a valley like depression which connects the facial and lingual papilla

Interdental gingiva is the part of gingiva which is present in the interdental space beneath area of tooth contact.

In the presence of diastema, the interdental gingiva is absent.

It is made up of the oral epithelium, sulcular epithelium and the junctional epithelium

• Dentogingival junction

• Gingival fibers

• Periodontal fibers

• Alveolar mucosa

Answer explanation

The dentogingival junction or gingival epithelium is comprised of:

1. Oral epithelium - covers the crest and outer surface of marginal and attached gingiva

2. Sulcular epithelium - lines the gingival sulcus

3. Junctional epithelium - provides attachment and acts as barrier to the tooth, allow GCF flow and provide antimicrobial substances

Which of the following gingival fibers group does NOT provide attachment of gingiva to the tooth and to the bony structure?

• Transseptal fibers

• Dentoperiosteal fibers

• Alveologingival fibers

• Dentogingival fibers

Answer explanation

Dentogingival, dentoperisteal and alveologigival fibers provide attachment of gingiva to the tooth and to the bony structure.

Fibers of circular, semicircular, transgingival, intergingival and transseptal fibers connect teeth to one another.

The largest fiber group in the periodontal ligament is:

• Transseptal fibers

• Oblique fibers

• Horizontal fibers

• Apical fibers

Answer explanation

1. Transseptal group - cementum to cementum; reconstructed even after alveolar bone destruction

2. Alveolar crest group - cementum to alveolar crest; mainly prevent teeth extrusion

3. Horizontal group - cementum to alveolar bone at right angle

4. Oblique group - largest group; bear vertical stresses

5. Apical group - cementum to bone at apical region

6. Interradicular group - between roots of multi-rooted teeth

The ends of periodontal fibers that are embedded in alveolar bone and cementum are called...

• Gingival fibers

• Collagen fibers

• Sharpey's fibers

• Epithelial rests of Malassez

Answer explanation

On the cementum side, these Sharpey's fibers are much thinner in diameter and insert at closer intervals as compared with alveolar bone side.

The term lamina dura refers to the radiographic image of the

• Periodontal ligament space

• Alveolar bone proper

• Cortical plates

• Alveolar crest

Answer explanation

PARTS OF ALVEOLAR BONE

1. Alveolar bone proper - thin lamella of bone that surrounds the root of the tooth and gives attachment of periodontal ligament

2. Supporting alveolar bone

Cortical plates - compact bone forming the outer and inner plates of alveolar bone

Spongy bone - fills area between the plates and alveolar bone proper