Please enable JavaScript.
Coggle requires JavaScript to display documents.
Functional Anatomy of The Oral Cavity and Dentition - Coggle Diagram
Functional Anatomy of The Oral Cavity and Dentition
Components of the Oral Cavity
Boundaries
Vermillion border of upper and lower lip
Cheeks on the side
Hard and soft palate of the roof
Floor of the mouth
Upper jaw (maxilla) and lower jaw (mandible) support the teeth
Posterior boundary
palatoglossal folds
Opens into the oropharynx throguht he fauces
uvula extends from the soft palate and is located at the opening of the oropharynx, posterior to the oral cavity
Components
Upper and lower dental arches
Vestibule of the mouth
Oral Cavity proper
Tongue
Anterior 2/3 is visible in the oral cavity
Dorsal surface is rough with minute papillae and taste buds
Ventral surface is smooth with 2 thin serrated folds
Frenulum controls range of movement
Floor of the Mouth
Roof of sublingual space
Lined by mucous membrane
Inner surface of the body of the mandible where it becomes continuous
Centrally becomes continuous with the mucous membrane covering the anterior 2/3 of the tongue
Roof of the mouth
Cheeks
Opening of duct of parotid gland
Mucous membrane
Stratified squamous epithelium bound to underlying bone
Teeth and Gums
Alveolar process of maxilla and mandible support the teeth
Gingiva is the mucosa surrounding the tooth that is designed for chewing, attached in part to the cementum of the tooth and in part of the alveolar bone
Retromolar Region
Extends from the back of the last lower molar below to the back of last upper molar above
mucous membrane is firmly attached to the underlying muscle and bone and contains some mucous glands
Role in Digestion
Saliva moistens and compacts chewed food
Muscles of Mastication
Occlusion
Stable
Maximum support to muscles and joint
Unstable
muscles of mastication malfunction, increase in load/pressure on the TMJ, pain, damage, degeneration
TMJ
Components
Mandibular condyle: Round end of mandible, translates, rotates during function
Temporal Fossa: Socket for condyle
Articular Eminence: Hold disc to condyle; help stabilize joint
Articular Disc (meniscus): cartilage-like dense collagen; between condyle and fossa
Ligaments: hold disc to the condyle; help stabilize the joint
Connective tissue: hold disc to back of the joint; contains blood vessels and nerves
Masseter
Origin: zygomatic arch/zygomatic bone
Insertion: lateral surface of ramus and angle of mandible
Nerve supply: masseteric nerve from mandibular division of trigeminal nerve V
Action: Elevates mandible, powerful chewing muscle
Temporalis Muscle
Origin: Temporal fossa/temporal fascia
Insertion: Coronoid process and anterior surface of ramus of mandible
Nerve Supply: Anterior and posterior deep temporal nerves from mandibular of trigeminal nerve V
Action: Elevates mandible, retracts mandible
Lateral Pterygoid Muscle
Origin: Superior head-greater wing of sphenoid, Inferior head: lateral surface of lateral pterygoid plate
Insertion: Superior head - capsule and articular disc of TMJ, inferior head: Neck of Mandible
Nerve supply: lateral pterygoid branch of mandibular branch of mandibular divison of trigeminal nerve V
Action: protracts mandible, opens mouth
Medial Pterygoid Muscle
Origin: Medial surface of lateral pterygoid plate, pyramidal process of palatine bone, tuberosirty of maxilla
Insertion: Medial surface of ramus and angle of mandible
Nerve Supply: Medial pterygoid branch of mandibular division of trigeminal nerve V
Action: Elevates and protracts mandible
Tooth Anatomy
Calcified tissues
Enamel: Extremely hard, highly mineralized, crystalline structure, covers and protects the crown, and surface for chewing, grinding, crushing of food
Dentin: Bone-like core of the tooth, substructure for rigid enamel, unique structure of dentinal tubules
Cementum: Thin calcified covering of the root
Central pulp cavity: Connective tissue, blood vessels, nerves
Supporting structure: gingivae
Periodontal ligaments: Attaches root to the surrounding alveolar bone of the socket
Alveolar bone: Thin layer of compact bone that forms the tooth socket surrounding the roots
Primary and Permanent Dentition
Four types of teeth
Incisors (cutting teeth)
4 front-most teeth per jaw used for the initial biting of food
Canines
2 per jaw: used to bite into/tear food
Premolars
2 on each side per jaw: Similar to molars for form and function
Molars
2-3 on each side per jaw, larger than premolars, used for crushing and grinding food
Primary dentition
20 teeth - (Incisors, canines, molars), smallers, whiter, more prone to wear and important for maintaining space for developing permanent dentition
Mixed
Variable: transitional grouped into incisors, canines, molars, premolars, both primary and permanent in varying
Permanent
32 teeth - (incisors, canines, premolars, molars), more calcified stronger than primary teeth
Dental Anomalies
Ankyloglossia
Etiology
Lingual frenulum is abnormally short and thick
Malocclusion
The way teeth fit together
Factors involved in normal occlusal development
Malalignment of teeth (dental malocclusion), crowding, spacing, tipping, rotation, dental deterioration
jaw relationship discrepancy, airway, low muscle tone, oral habits
Anomalies of Tooth number
Supernumerary Teeth: Extra Teeth
Oligodontia: Congenitally Missing teeth
Anomalies of Tooth Structure
Amelogenesis Imperfecta: Heritable enamel defect
Dentinogenesis Imperfecta: Heritable dentin structure abnormality, may occur with osteogenesis imperfeta
Anomalies of tooth shape/size
Talon Cusp
Conical Supernumerary tooth
Conditions with associated anomalies
Turner's Syndrome: Enamel Hypoplasia
Ehlers-Danlos Syndrome: Irregular dentin tubules with inclusions, intrapulpal calcifications
Cleidocranial dysplasia: delayed exfoliation of primary, delayed eruption of permanent teeth, supernumerary teeth, roots lack cellular cementum
Cleft lip/Palate: Congenitally missing teeth, supernumerary teeth, enamel hypoplasia
Cleft Lip/Cleft Palate: Congenitally missing teeth, supernumerary teeth, enamel hypoplasia
Down Syndrome: Microdontia, Enamel hypoplasia, Oligodontia, Supernemerary teeth, tooth morphology, Rotated teeth, Delayed eruption
Ectodermal Dysplasia: Conical Crowns, oligodontia, maxillary hypoplasia, Delayed eruption