Oral cavity designed for eating , talking and breathing . oral cavity extend anteriorly  from lips to posteriorly up to palatoglosaal  arch  and it is enclosed by the lips of and cheeks. Oral cavity consist of vestibule and oral cavity proper

Vestibule is the space between cheeks / lips and teeth /gums . vestibule communicate with exterior of mouth through oral fissure which is formed by lips. Internally vestibule communicate with oral cavity proper posterior to the 3^rd molar tooth .Parotid duct open into vestibule at opposite crown of the 2^nd upper molar tooth . Lips are fleshy fold line externally by skin and internally by mucus membrane. Lymphatics from Central part of lower lips drained into submandibular lymph node rest of lymph from lips drained into submandibular nodes. Cheeks are fleshy flaps form the large part of face.

Oral cavity proper is inside the teeth, gums, alveolar arch . posteriorly communicate with oropharynx through oro pharyngeal isthmus .Is roof is formed by hard and soft palette. Floor is formed by tongue Oral cavity is line with stratified squamous epithelium  .

Gums or gingivae are firmly attached to the periosteum of the alveolar bone and extend around nck of tooth