Oral Structures Adapted to Function PDF

Oral structures adapted to function ILOs (objective): Anatomical structure of mouth and teeth and understanding the relationship of this to function by/Dr. Mohamed Abdulrahman Prof of Oral Biology Year 1 Director in MMDP Functions...

Oral structures adapted to function ILOs (objective): Anatomical structure of mouth and teeth and understanding the relationship of this to function by/Dr. Mohamed Abdulrahman Prof of Oral Biology Year 1 Director in MMDP Functions of the Oral Cavity Entry of food Entry of air (breathing) Mastication (chewing) Deglutition (swallowing) Sensation : taste (bitter, sour , salty, sweety ) & general (heat &cold) Speech – modification of sound Facial expression Extra hand Boundaries of the Oral Cavity Extends from oral fissure to pharynx Roof ( hard & soft palate) Walls (cheeks & lips) Floor ( muscles) vestibule oral cavity proper A: The Tongue Functions – Sensation Taste: so has tongue papilla with taste buds General sensation – Articulation: so freely mobile and has ability to form and deform – Swallowing: intrinsic &extrinsic muscles – Chewing: intrinsic muscles &lingual frenum What is it made of?  Ventral surface Dorsal surface Compare the color and texture of the dorsal and ventral surfaces. Why are they different? Tongue papillae with taste buds B- Teeth and their hard tissue: 1- 2 sets of dentition (primary and permanent) to accommodate increase in function from childhood to adulthood 2-Enamel : has 96% minerals. It is the hardest tissue to withstand masticatory force and protect underlying dentin so, it is formed of parallel rods or prisms with maximum strength at cusp tip, (which is the more stress bearing area). Enamel is extremely hard comparable to mild steel. 3-Dentin: Dentin: contains 76% minerals. It forms the main bulk of the tooth. It is viscoelastic (unlike enamel) when subjected to slight deformation. The elastic property is important for proper functioning of the tooth to provide flexibility and resistance to fracture of the overlying brittle enamel. Dentin is sensitive and its sensitivity considered a defense mechanism for protection vitality of the tooth Increase the thickness of dentin with increasing age aims in pulp protection 4- Variations in occlusal form of teeth come in accordance with the variation in function. muscles of mastication are located laterally to the mouth that enhance great force applied on molars area  C-Pulp Pulp is enclosed inside a well defined solid dentin room. In crown is called pulp chamber and in root called root canals Pulp is innervated tissue so it is the source of pain perception that limit the ingress of toxins and bacteria  D- Periodontal Ligament It is a specialized soft fibrous tissue occupy the periodontal space (around the tooth)  Lodging force Different orientation and direction with variation in origin and insertion help to well distribution of force.(what types of force ?).Lodging and dislodging Dislodging force  E- Salivary glands Are exocrine merocrine glands pour their saliva secretion into the oral cavity Major and minor glands Two types of secretions mucous and serous (watery) Saliva maintains the well-being of the mouth as it forms a film of fluid that coat the teeth and oral mucosa Protection, digestion , taste function, antimicrobial, wetting bolus of food facilitate swallowing  F-Oral mucosa Keratinized (has a layer of keratin above) oral mucosa protect the underlying tissue and withstand friction of food. found in hard palate and gingiva, (area subjected to friction and high force)  Gingival stippling accommodate to withstand impact force G-Tempro- Mandibular Joint Allow movement in all direction: lateral, ant post and rotational so attached to different muscles and ligament