Gingiva
Gingiva
Also known as: gums, gingivae
The gingiva is the firm, keratinised masticatory mucosa that covers the alveolar processes and surrounds the necks of the teeth. It seals the tooth–gum junction against bacteria.
Overview
The free (marginal) gingiva forms a collar around each tooth. The shallow gingival sulcus between it and the tooth is up to about 3 mm deep in health. The attached gingiva is bound firmly to the alveolar periosteum and cementum and ends at the mucogingival junction, beyond which lies loose, red alveolar mucosa. The interdental papillae fill the spaces between teeth. At the base of the sulcus, the junctional epithelium attaches to the enamel by hemidesmosomes and a basal lamina. This is the weak point where periodontal disease begins.
- Location
Around the necks of the teeth and over the alveolar processes of the maxilla and mandible.
Anatomy
- Innervation
Upper gingiva: superior alveolar, greater palatine and nasopalatine nerves (V2). Lower gingiva: inferior alveolar/mental, buccal and lingual nerves (V3).
- Histology
Keratinised or parakeratinised stratified squamous epithelium with long rete ridges over dense collagenous lamina propria. The sulcular and junctional epithelia are non-keratinised.
Function
- Seals the periodontium from the oral environment.
- Resists friction during chewing (keratinised masticatory mucosa).
- Gingival crevicular fluid adds immune cells and antibodies to the sulcus.
Clinical significance
Gingivitis and gingival changes
Plaque-induced gingivitis (red, swollen gums that bleed) is reversible. Gingival overgrowth is caused by phenytoin, ciclosporin and nifedipine. Bleeding, swollen gums are a classic sign of scurvy (vitamin C deficiency). A blue-grey gingival line (Burton line) suggests lead poisoning.
Compiled from standard anatomy and physiology references — see the Digestive System sources. For education only; not medical advice.