Teeth *A highly mineralized outer part *inner pulp cavity. Mineralized tissues of teeth: 1- Enamel 2-Dentin 3-cementum 1-Enamel: a-Enamel prisms (in organic material) b-the prisms have cross striation 2-dentin: a-resembles that of bone. b-Originate from odontoblasts 3-cementum: a-composed of lamellae b-cementocytes with in lacunae c-A perforating cementum fibers extend into the bony socket which form periodontal membrane

Dental pulp 1-composed of connective tissue fibers matrix, cells, numerous blood vessels and nerves. Salivary glands 1-major salivary glands 2-minar salivary glands 1.major salivary glands: a-parotid b-mandibular c-sublingual d-zygomatic-carnivors e-molar- cat 2-minor salivary glands: a-labial b-lingual c-buccal d-palatine

parotid salivary gland: *serous glands *compound tubuloacinar gland *has lobular units *the lobule consists of acini secretory units *myoepithlial cells located between the secretory cells and the basement membrane *the lumen of the a sinus opens into a short intercalated duct which join the striated duct *striated salivary duct join the interlobular duct *interlobular ducts converge to form the main parotid duct.

Intercalated duct ---- striate salivary duct ----inter lobular duct---main parotid duct Mandibular salivary gland:  compound branched tubuloacinar gland. *mixed gland (both mucous and serous acini). *mucous secreting cells border the lumen, and serous demi lunes occur at the periphery. *myoepithlial cells are present. *intercalated ducts---striated ducts---interlobular ducts---main parotid duct. Minor salivary glands: lingual glands:- *located in the submucosa and between muscle bundles of the tongue. *secretory units are in the form of acini tubuloacinar or tubular ???

Figure1. The structure of submandibular (submaxillary) gland. The secretory portions are composed of pyramidal serous (light blue) and mucous (light yellow) cells. Serous cells are typical protein-secreting cells, with rounded nuclei, accumulation of rough endoplasmic reticulum in the basal third, and an apex filled with protein-rich secretory granules. The nuclei of mucous cells, flattened with condensed chromatin, are located near the bases of the cells. The short intercalated ducts are lined with cuboidal epithelium. The striated ducts are composed of columnar cells with characteristics of ion-transporting cells, such as basal membrane invaginations and mitochondrial accumulation. Myoepithelial cells are shown in the serous secretory endpieces.

Pharynx *mucosa:- *stratified squamous epithelium supported by lamina propria of connective tissue + mucous glands * Lacks a lamina muscularis *Adventitia : is a C.T. layer. Esophagus *tunica mucosa (ep. Mucosa ): stratified squamous epithelium. Lamina propria : connective tissue Lamina muscularis : smooth muscle bundles *Tunica submucosa : Losse C.T. +seromucosa, mucous acini *Tunica muscularis + striated M.-circular and longitudinal layer *Tunica adventitia : losse C.T. + BVs + nerve + lymph Vs.