Next we’ll look at the submandibular gland. The submandibular gland lies under the posterior part of the body of the mandible.
We’ll start by looking at a dissection in which the gland has been removed. Again, we’ll take the opportunity to review the bony and muscular anatomy.
Here’s the body of the mandible, here’s the body of the hyoid bone. Here’s the anterior belly of the digastric, here’s the digastric tendon, passing through the stylohyoid muscle. Here’s the mylohyoid muscle, here’s the styoglossus. Here, deep to the digastric, is the the hyoglossus muscle.
Now we’ll add the submandibular gland to the picture. Here it is. The submandibular gland curls around behind the free border of the mylohyoid muscle, so that it has a superficial part, which we can see here, and a deep part. To see the deep part we’ll remove the superficial part.
Here’s the cut edge of the deep part of the submandibular gland, between the mylohyoid and styloglossus muscles. It extends forward to about here.
The saliva that’s produced by the submandibular gland passes into the submandibular duct, which runs forwards in the floor of the mouth. To see the duct, and also to see the third salivary gland, the sublingal gland, we’ll look at a specimen consisting of the mandible, the tongue, and the floor of the mouth. We’ll remove the alveolar process, and we’ll remove the mucous membrane.
Here, just beneath the mucous membrane, is the sublingual gland which we’ll see in a moment. For now, we’ll remove it too, to see the submandibular duct. The submandibular duct runs forward in the floor of the mouth alongside the base of the tongue. It ends here, just beside the frenum. To see where it starts we’ll go round to the back.
Here’s the submandibular duct, here’s the submandibular gland. The duct passes forward in the interval between the mylohyoid muscle, and the muscles of the side of the tongue, the hyo- and styloglossus muscles.
Now we’ll go round to the front again, and put the sublingual gland back in the picture. The sublingual gland is thin, flat, and somewhat diffuse. It lies alongside the base of the tongue, just lateral to the genioglossus muscle.
The saliva formed by the sublingual gland enters the oral cavity by way of several very small openings in the mucous membrane of the floor of the mouth. The openings are too small to see here.