Not included in oral cavity Ca -a) Base of tongueb) Gingivobuccal sulcusc) Soft palated) Hard palatee) Buccal mucosa
The vermilion border of the lips is the anterior boundary of the oral cavity, while the anterior tonsillar pillars, the posterior aspect of the hard palate, and the circumvallate papillae of the tongue are the posterior boundary.
Subsites are : -


The vermilion surfaces of the lips.
The alveolar process of the mandible.
The alveolar process of the maxilla.
The retromolar trigone, which is the mucosa overlying the ascending ramus of the mandible behind the last lower molar tooth.
The hard palate.
The buccal musoca, which lines the cheeks and inner aspects of the lips and includes the upper and lower buccoalveolar gutters.
The floor of the mouth.
The anterior two-third of the tongue (oral tongue), which is limited posteriorly by the circumvallate papillae and includes the tip, dorsum, lateral borders, and undersurface of the oral tongue.
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