More Related Content
Similar to Anatomy of tooth
Anatomy of tooth
- 1. DENTAL ANATOMY & PHYSIOLOGY DrGangaprasad Waghmare
- 2. Dental Anatomy andPhysiology •Primary (deciduous) •Secondary (permanent) Definition (teeth): There are two definitions
- 3. Dental Anatomy andPhysiology A tooth is made up of three elements: •Water •Organic materials •Inorganic materials Elements
- 4. Primary (deciduous) • Consistof 20 teeth • Begin to form during the first trimester of pregnancy • Typically begin erupting around 6 months • Most children have a complete primary dentition by 3 years of age Dental Anatomy and Physiology Dentition (teeth): There are two dentitions 1. Oral Health for Children: Patient Education Insert. Compend Cont Educ Dent.
- 5. Dental Anatomy andPhysiology Secondary (permanent) • Consist of 32 teeth in most cases • Begin to erupt around 6 years of age • Most permanent teeth have erupted by age 12 • Third molars (wisdom teeth) are the exception; often do not appear until late teens or early 20s Dentition (teeth): There are two dentitions Mandible Maxilla Incisors Canine (Cuspid) Premolars Molars
- 6. Classification of Teeth: •Incisors (central and lateral) • Canines (cuspids) • Premolars (bicuspids) • Molars Dental Anatomy and Physiology Identifying Teeth Incisor Canine Premolar Molar
- 7. Dental Anatomy andPhysiology Identifying Teeth2 Incisor Canine Premolar Molar • Incisors function as cutting or shearing instruments for food. • Canines possess the longest roots of all teeth and are located at the corners of the dental arch. • Premolars act like the canines in the tearing of food and are similar to molars in the grinding of food. • Molars are located nearest the temporomandibular joint (TMJ), which serves as the fulcrum during function.
- 8. Dental Anatomy and Physiology •Apical • Labial • Lingual • Distal • Mesial • Incisal Teeth: Identification Tooth Surfaces Labial Apical Lingual Distal Apical Mesial Incisal Incisal
- 9. Dental Anatomy and Physiology •Apical: Pertaining to the apex or root of the tooth • Labial: Pertaining to the lip; describes the front surface of anterior teeth • Lingual: Pertaining to the tongue; describes the back (interior) surface of all teeth • Distal: The surface of the tooth that is away from the median line • Mesial: The surface of the tooth that is toward the median line Labial Apical Lingual Distal Apical Mesial
- 10. Enamel Alveolar Bone Pulp Chamber Dental Anatomyand Physiology • Enamel (hard tissue) • Dentin (hard tissue) • Odontoblast Layer • Pulp Chamber (soft tissue) • Gingiva (soft tissue) • Periodontal Ligament (soft tissue) • Cementum (hard tissue) • Alveolar Bone (hard tissue) • Pulp Canals • Apical Foramen The Dental Tissues: Dentin Odontoblast Layer Gingiva Periodontal Ligament Cementum Pulp Canals Apical Foramen
- 11. • Anatomic Crown •Anatomic Root • Pulp Chamber The 3 parts of a tooth: Anatomic Crown Anatomic Root Pulp Chamber Dental Anatomy and Physiology
- 12. Anatomic Crown Anatomic Root Pulp Chamber DentalAnatomy and Physiology • The anatomic crown is the portion of the tooth covered by enamel. • The anatomic root is the lower two thirds of a tooth. • The pulp chamber houses the dental pulp, an organ of myelinated and unmyelinated nerves, arteries, veins, lymph channels, connective tissue cells, and various other cells.
- 13. Dental Anatomy andPhysiology • Enamel • Dentin • Cementum • Dental Pulp The 4 main dental tissues: Enamel Dentin Cementum Dental Pulp
- 14. • Structure • Highlycalcified and hardest tissue in the body • Crystalline in nature • Enamel rods • Insensitive—no nerves • Acid-soluble—will demineralize at a pH of 5.5 and lower • Cannot be renewed • Darkens with age as enamel is lost • Fluoride and saliva can help with remineralization Dental Tissues—Enamel2 Dental Anatomy and Physiology
- 15. • Enamel canbe lost by:3,4 – Physical mechanism • Abrasion (mechanical wear) • Attrition (tooth-to-tooth contact) • Abfraction (lesions) – Chemical dissolution • Erosion by extrinsic acids (from diet) • Erosion by intrinsic acids (from the oral cavity/digestive tract) • Multifactorial etiology – Combination of physical and chemical factors Dental Tissues—Enamel2 Dental Anatomy and Physiology
- 16. • Softer thanenamel • Susceptible to tooth wear (physical or chemical) • Does not have a nerve supply but can be sensitive • Is produced throughout life • Three classifications • Primary • Secondary • Tertiary • Will demineralize at a pH of 6.5 and lower Dental Tissues—Dentin2 Dental Anatomy and Physiology
- 17. Three classifications: • Primarydentin forms the initial shape of the tooth. • Secondary dentin is deposited after the formation of the primary dentin on all internal aspects of the pulp cavity. • Tertiary dentin, or “reparative dentin” is formed by replacement odontoblasts in response to moderate-level irritants such as attrition, abrasion, erosion, trauma, moderate-rate dental caries, and some operative procedures. Dental Tissues—Dentin2 Dental Anatomy and Physiology
- 18. Dentin Pulp Tubule Fluid Nerve Fibers Odontoblast Cell DentalAnatomy and Physiology • Dentinal tubules connect the dentin and the pulp (innermost part of the tooth, circumscribed by the dentin and lined with a layer of odontoblast cells) • The tubules run parallel to each other in an S- shape course • Tubules contain fluid and nerve fibers • External stimuli cause movement of the dentinal fluid, a hydrodynamic movement, which can result in short, sharp pain episodes Dental Tissues—Dentin (Tubules)2
- 19. Dental Anatomy and Physiology •Presence of tubules renders dentin permeable to fluoride • Number of tubules per unit area varies depending on the location because of the decreasing area of the dentin surfaces in the pulpal direction Dental Tissues—Dentin (Tubules)2
- 20. Association between erosionand dentin hypersensitivity3 • Open/patent tubules – Greater in number – Larger in diameter • Removal of smear layer • Erosion/tooth wear Enamel Exposed Dentin Receding Gingiva Tubules Odontoblast Dental Anatomy and Physiology Dental Tissues—Dentin (Tubules)2
- 21. Dental Anatomy andPhysiology • Thin layer of mineralized tissue covering the dentin • Softer than enamel and dentin • Anchors the tooth to the alveolar bone along with the periodontal ligament • Not sensitive Dental Tissue—Cementum2
- 22. • Innermost partof the tooth • A soft tissue rich with blood vessels and nerves • Responsible for nourishing the tooth • The pulp in the crown of the tooth is known as the coronal pulp • Pulp canals traverse the root of the tooth • Typically sensitive to extreme thermal stimulation (hot or cold) Dental Tissue—Dental Pulp2 Dental Anatomy and Physiology
- 23. • Pulpitis isinflammation or infection of the dental pulp, causing extreme sensitivity and/or pain. • Pain is derived as a result of the hydrodynamic stimuli activating mechanoreceptors in the nerve fibers of the superficial pulp (A-beta, A-delta, C-fibers). • Hydrodynamic stimuli include: thermal (hot and cold); tactile; evaporative; and osmotic • These stimuli generate inward or outward movement of the fluid in the tubules and activate the nerve fibers. • A-beta and A-delta fibers are responsible for sharp pain of short duration • C-fibers are responsible for dull, throbbing pain of long duration • Pulpitis may be reversible (treated with restorative procedures) or irreversible (necessitating root canal). • Untreated pulpitis can lead to pulpal necrosis necessitating root canal or extraction. Dental Tissue—Dental Pulp2,5 Dental Anatomy and Physiology
- 24. • Gingiva • AlveolarBone • Periodontal Ligament • Cementum Periodontal Tissues6 Dental Anatomy and Physiology Gingiva Alveolar bone Cementum Periodontal Ligament
- 25. • Gingiva: Thepart of the oral mucosa overlying the crowns of unerupted teeth and encircling the necks of erupted teeth, serving as support structure for subadjacent tissues. Dental Tissue—Dental Tissue6 Dental Anatomy and Physiology Gingiva
- 26. • Alveolar Bone:Also called the “alveolar process”; the thickened ridge of bone containing the tooth sockets in the mandible and maxilla. Dental Tissue—Dental Tissue6 Dental Anatomy and Physiology Alveolar bone
- 27. • Periodontal Ligament:Connects the cementum of the tooth root to the alveolar bone of the socket. Dental Tissue—Dental Tissue6 Dental Anatomy and Physiology Periodontal Ligament
- 28. • Cementum: Bonelike,rigid connective tissue covering the root of a tooth from the cementoenamel junction to the apex and lining the apex of the root canal. It also serves as an attachment structure for the periodontal ligament, thus assisting in tooth support. Dental Tissue—Dental Tissue6 Dental Anatomy and Physiology Cementum
- 29. • Plaque • Saliva •pH Values • Demineralization • Remineralization Oral Cavity/Environment7,8 Dental Anatomy and Physiology
- 30. Dental Anatomy and Physiology Plaque:7,8 •is a biofilm • contains more than 600 different identified species of bacteria • there is harmless and harmful plaque • salivary pellicle allows the bacteria to adhere to the tooth surface, which begins the formation of plaque Oral Cavity
- 31. Dental Anatomy and Physiology Saliva:7,8 •complex mixture of fluids • performs protective functions: – lubrication—aids swallowing – mastication – key role in remineralization of enamel and dentin – buffering Oral Cavity
- 32. Dental Anatomy and Physiology pHvalues:7,8 • measure of acidity or alkalinity of a solution • measured on a scale of 1-14 • pH of 7 indicated that the solution is neutral • pH of the mouth is close to neutral until other factors are introduced • pH is a factor in demineralization and remineralization Oral Cavity 3. Strassler HE, Drisko CL, Alexander DC.
- 33. Dental Anatomy and Physiology Demineralization:7,8 •mineral salts dissolve into the surrounding salivary fluid: – enamel at approximate pH of 5.5 or lower – dentin at approximate pH of 6.5 or lower • erosion or caries can occur Oral Cavity
- 34. Dental Anatomy and Physiology Remineralization:7,8 •pH comes back to neutral (7) • saliva-rich calcium and phosphates • minerals penetrate the damaged enamel surface and repair it: – enamel pH is above 5.5 – dentin pH is above 6.5 Oral Cavity