Vestibular lamina

The vestibular lamina also termed as lip furrow band is a proliferation of cells into ectomesenchyme tissue. Responsible for the formation of the vestibule (the space bordered by the junction of the gingiva and the tissue of the inner cheek), the vestibular lamina is usually contrasted with the dental lamina, which develops concurrently and is involved with developing teeth. Both the vestibular lamina and the dental lamina arise from a group of epithelial cells, called the primary epithelial band.

Explanation:- The vestibular lamina develops at 6th week of the intrauterine life as a result of proliferation of the primitive ectoderm that lines the primitive oral cavity labial and buccal to the dental lamina. The cells enlarge and then degenerate to form a cleft that separates the lips and cheeks at one side from the developing jaws and teeth at the other side. This cleft is the oral vestibule.

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