Three-dimensional architecture of the subepithelial connective tissue layer in the mouse retromolar region.

The three-dimensional architecture of the subepithelial connective tissue layer in the mouse retromolar region was studied by scanning electron microscopy after removal of the epithelial layer. The connective tissue papillae (CTP) of the taste bud papillae (the retromolar papillae) appeared as a barnacle-like in form and had the round depression, corresponding to the site of taste bud, on their top. The CTP of the retromolar papillae and the openings of the salivary glands were concentrated collectively in the narrow zone just posterior to the molar teeth. This topographical relationship seems to reflect a physiological function; i.e., the food ground by the molar teeth is dissolved in saliva and stimulates the taste buds in the retromolar papillae. Further, the conical or cylindrical CTP were arranged around the CTP of the retromolar papillae. It is suggested that the conical or cylindrical CTP play an important role in increasing the epithelial-connective tissue interface and in resisting the excessive force during mastication.