Digestive system 1 ➢ Oral cavity: • Lips, cheeks • Tongue • Palate - hard - soft • Tooth • The tunica mucosa – epithelial lining – lamina propria /loose connect. tissue/ – lamina muscularis mucosae • The submucosa (tela submucosa) /loose connect. tissue + Meissner´s nerve plexus/ • The tunica muscularis externa – circular • myenteric nerve plexus /Auerbachi/ – longitudinal smooth muscle • The tunica serosa or adventitia /loose connect. tissue -/+mesothelium/ Common structure of the wall of GIT tube tela submucosa Oesophagus The oral cavity (the tunica mucosa) The epithelium non-keratinized stratified squamous epithelium Lamina propria loose connective tissue Lamina muscularis mucosae is missing Lamina propria → the submucosa (loose connect. tissue) / periost / muscle 3 functional regions of oral mucosa: • covering - lined with submucosa (lips, cheeks, soft palate, facies mylohyoidea of the tongue) • masticatory – submucosa is missing, mucosa firmly attached to the periost of the bone, so called mucoperiost (gingiva and hard palate) • specialized – forms papillae (dorsum linguae) Labium oris External surface - skin Mucous membrane Transitional zone (vermilion) hair follicles m. orbicularis oris gll. labiales sebaceous glands Labium oris (transitional zone) The epithelium is somewhat thicker than in other parts of the facial skin. C.t. papilla extend deep into the epithelium and are heavily vascularized. It is the proximity of these vessels to the surface of the epithelium which gives the prolabium it's red appearance (+ presence of protein eleidin in the epithelial cells). c.t. papillae with blood capillaries inner surface stratified squamous epithelium lamina propria Tongue dorsal surface the tunica mucosa – papillae filiformes, fungiformes, circumvallatae, foliatae (papillae = elevations of the oral epithelium and lamina propria) the submucosa is missing aponeurosis linguae inferior surface (facies mylohyoidea) the tunica mucosa – without specific papillae the submucosa is present slizničního vaziva krytý epitelem jazyka lamina propria skeletal muscle fibers Apex linguae dorsum linguae facies mylohyoidea gl. apicis linguae - Blandini Apex linguae – facies inferior gl. apicis linguae - Blandini facies mylohyoidea lamina propria tela submucosa Papillae circumvallatae The epithelial lining – stratified squamous epithelium – taste buds Lamina propria mucosae – dense connect. tissue – serous (von Ebner) glands - drain into deep grooves primary papilla secondary papillae gll. gustatoriae (Ebneri) Papilla circumvallata (HE) groove gland duct taste bud Taste buds Circular groove Soft palate nasal surface oral surface aponeurosis palatina - skeletal muscle + connect. tissue gll. palatinae - mucous gll. nasales - mixed - ciliated pseudostratif. columnar ep.(metaplasia) - gll. nasales (mixed gl.) stratified squam. ep. duct Palatum molle original basement membrane - nasal surface Palatum molle duct basement membrane gll. palatinae – mucous stratified squamous epithelium - oral suface Anatomy Corona dentis (crown) Collum (neck) Radix (root) Cavum et canalis radicis dentis (pulp cavity) Pulpa dentis Apex radicis dentis + foramen apicis radicis dentis (apical foramen) Alveolus Periodontal ligament - dense connective tissue Tooth (dens) Deciduous (baby) teeth - 20 Permanent teeth - 28-32 radix (root) Tooth – grinding cementum enamel dentin dentinal tubules with odontoblast processes Tooth – root (HE) 5x odontoblasts pulp dentinal tubules with odontoblast processes Decalcified tooth - enamel is missing predentin – unmineralized dentin with nerve fibers pulp with odontoblasts dentin dentin odontoblasts D E N T I N C E M E N T U M B O N E P E R I D O N T I U M Periodontal ligament – dense connective tissue Cementum Alveolar bone – woven bone gingiva libera gingiva affixa epithelial attachment of Gottlieb (junctional epithelium) = epithelium of gingiva is bound to the tooth enamel sulcus gingivalis Gingiva - stratified squamous epithelium - connective tissue papillae – dense collagen c.t. (no tela submucosa) dentin bone bone Digestive system – I Slides : 1. Labium oris (HE) 2. Apex linguae (HE) 3. Papilla circumvallata (HE) 5. Palatum molle (HE) 7. Tooth (HE) 11. Oesophagus (HE, HES) 97. Tooth – development (Azan) Atlas: Development of face (87) Pharyngeal (branchial) apparatus. Development of tongue (88) Tooth – development (99-100) Development of the face, stomodeum and cervical region – embryo, day 24 stomodeum brain pharyngeal membrane perikardiac cavity foregut chorda dorsalis proc. frontonasalis proc. maxillaris proc. mandibularis stomodeum cardiac bulge A – sagittal section B – frontal view Rathke‘s pouch body ectoderm Development of the face, stomodeum and cervical region – embryo, day 28 pharyngeal membrane (perforated) Rathke‘s pouch chorda dorsalis 1st– 4th endodermal pouch proc. frontalis proc. nasalis med. + lat. nasal placode proc. maxillaris proc. mandibularis 2nd and 3rd branchial arch pharynx Development of the face – embryo, end of week 5 nasal placode Development of pharyngeal (branchial) apparatus – embryo, week 6 pharyngeal (branchial) arches eminentia hypobranchialis oesophagus ectomesenchyme endoderm ectoderm nerve base of visceral muscles cartilage aortic arch (branchial artery) sensitive and motor branches of nerve development of tongue ECTODERMAL CLEFTS and ENDODERMAL POUCHES – embryo, week 5 pharyngeal arches 1-4 meatus acusticus ext. (cleft 1) sinus cervicalis (clefts 2, 3, 4) cavum tympani, tuba auditiva (Eustachii) sinus (fossa) tonsillaris gl. parathyreoidea inf. thymus gl. parathyreoidea sup. ultimobranchial corpuscle 1. membrana obturans  membrana tympani Development of tongue sulcus terminalis laryngotracheal diverticle (development of respiratory system) thyroid gland eminentia hypobranchialis epiglotic swelling arytenoid swelling ectodermal lining endodermal lining Development of palate – embryo, A – week 7, B – week 8, C – week 10 sensory epithelium septum nasi nasal cavity palatine processes tongue oral cavity palatine processes fusion tongue Development of the oral cavity and teeth – embryo, week 6 upper lip lower lip ectoderm cartilago Meckeli dental lamina + tooth bud dental lamina + tooth cap base of tonguevestibular band ectoderm organ of enamel dental papilla permanent tooth deciduous tooth labium vestibulum primary dental lamina Development of the teeth – embryo, week 6 primary dental lamina 1. stage of dental bud 2. stage of dental cap 3. stage of dental bell 4. stage of apposition (dentinogenesis and amelogenesis) 5. stage of eruption Developmental stages of tooth 1 2 3 54 Tooth – bell stage