The characteristic stippling observed on the gingival surface is primarily due to the presence of the connective tissue papillae. This stippling gives the gingiva its dimpled appearance, which is often compared to the texture of an orange peel.

- The connective tissue papillae are projections of the underlying connective tissue that extend into the epithelium of the gingiva.
- These papillae create anchoring points and contribute to the distinctive textural pattern seen on the attached gingiva.
- The stippling is a result of the close interdigitation between the connective tissue papillae and the overlying epithelial rete pegs, leading to variations in surface contour.
- In contrast, the gingival sulcus epithelium and junctional epithelium are specialized epithelial layers related to the attachment and sulcus depth but do not contribute to surface texture.
- The alveolar mucosa is a movable, nonkeratinized tissue lacking stippling.

In summary, the presence of the connective tissue papillae underlying the gingival epithelium is responsible for the characteristic stippled appearance of healthy attached gingiva.

Reference: Oral Histology: Development, Structure, and Function, Volume 3, Chapter 5, Page 142