Where the two tissue types meet is known as a mucogingival junction.

A mucogingival junction is an anatomical feature found on the intraoral mucosa.

Lugol's iodine may also be used to better visualize the mucogingival junction in the mouth.

The clinical importance of the mucogingival junction is in measuring the width of attached gingiva.

Because the palate is devoid of freely moveable alveolar mucosa, there is no mucogingival junction.

If the probe enters the sulcus and can descend up to or beyond the mucogingival junction, that area is said to represent a mucogingival defect.

The facial aspect of the attached gingiva extends to the relatively loose and movable alveolar mucosa, from which it is demarcated by the mucogingival junction.

There are three mucogingival junctions: on the facial of the maxilla and on both the facial and lingual of the mandible.

Progression of NUP into tissue beyond the mucogingival junction characterizes necrotizing stomatitis, which has many features in similar with cancrum oris.

If the destruction continues unabated apically and reaches the junction of the attached gingiva and alveolar mucosa, the pocket would thus be in violation of the mucogingival junction and would be termed a mucogingival defect.

Thus, if the entire height of the keratinized gingiva, from the free gingival margin to the mucogingival junction is 8 mm, and the probing depth on the tooth at that location is 2 mm, the effective width of attached gingiva is 6 mm.

Vazirani-Akinosi technique - Invented by Sunder J. Vazirani in 1960 and later reintroduced in 1977 by Oyekunle J. Akinosi, a closed-mouth injection technique, the syringe is "advanced parallel to the maxillary occlusal plane at the level of the maxillary mucogingival junction."

Using the mucogingival junction as the boundary demarcating the apical border of the attached gingiva, a periodontal probe in inserted into the gingival sulcus to measure how much of the keratinized gingiva coronal to the mucogingival junction is in fact attached to the underlying bone.