Divisions, surfaces and tissues of the tooth; surrounding structures

Exam 1

1. Chapter 3 The Tooth and Its Surrounding Structures

2. Objectives At the completion of this chapter, you will be able to Identify the divisions, surfaces and tissues of the tooth and periodontium Describe location, composition, and function of each tooth tissue and surrounding structures

3. Divisions of the Tooth Divided into three sections Crown is the visible portion of the tooth covered in enamel Neck or cervix is where the crown joins the root Also referred to the cemento -enamel junction Root is the nonvisible area, located at the bone and covered in cementum

4. Divisions of the Tooth

5. Divisions of the Tooth As part of aging, bone and gingiva recede and a portion of the root is exposed When the crown and exposed root are visible together it is referred to as the clinical crown

6. Divisions of the Tooth

7. Surfaces of the Tooth Five surfaces each named according to its position in the arch Mesial is the surface closest to the midline Distal is the surface farthest/most distant from the midline

8. Surfaces of the Tooth Facial are the surfaces closest to the face or outer surfaces of the teeth, including Labial : facial surfaces of the anterior teeth; closest to the lips Buccal : facial surfaces of the posterior teeth or surfaces closest to the cheek Lingual are surfaces closest to the tongue or palate; all the inner surfaces

9. Surfaces of the Tooth Occlusal are chewing surfaces of the posterior teeth Incisal edge are biting surfaces of the anterior teeth The tooth has either an occlusal or incisal surface, they cannot have both.

10. Surfaces of the Tooth

11. Related Terms Other terms that relate to the surfaces of the teeth Proximal : surface that is next to adjacent tooth Interproximal : triangular space between adjacent teeth filled with interdental papilla Contact area : both the mesial and distal surfaces that touches the adjacent tooth

12. Related Terms Apex : tip of the root Line angle : area of the tooth where two surfaces meet Point angle : area of the tooth where three surfaces meet When describing the precise location of a tooth structure, divide the crown an root into thirds

13. Related Terms

14. Related Terms

15. Tissues of the Tooth Enamel : protective layer of the tooth Hardest tissue in body 96% inorganic, 4% organic matter and water Varies in thickness Cementum : covers the root Same density as bone 50% inorganic, 50% organic and water Can regrow itself

16. Tissues of the Tooth Dentin is major portion of crown and root Harder than bone 70% inorganic, 30% organic matter and water Organic matrix of dentinal tubules Tubules filled with dentinal fibrils, carry sensation from enamel to pulp

17. Tissues of the Tooth Pulp Assists in production of dentin Located at innermost portion of tooth and is the only soft tissue Pulp chamber in the crown and pulp canal in the root make up the pulp cavity Vessels of pulp enter and exit through a small apical foreman

18. Tissues of the Tooth

19. The Periodontium Structures that surround and support the teeth Cementum is considered a support structure containing fibers extending to the periodontal ligament Periodontal ligament are fibers that support and suspend the tooth in the alveolus or socket

20. The Periodontium Alveolar process supports and stabilizes the root, comprised of two layers of bone tissue The inner lightweight, porous is the cancellous or trabecular bone The compact or cortical bone is a more dense layer structured to endure stress

21. The Periodontium

22. The Periodontium Gingiva is mucosa covered epithelial tissue visible in the oral cavity; divided into two sections Free gingiva : surrounds the cervix of the tooth like a collar and fills the interproximal space. Unattached on inner surface, creating a space called gingival sulcus Attached gingiva : paler pink and can be observed on the external surface. Merges with free gingiva at the free gingival junction

23. The Periodontium

24. https://www.purposegames.com/game/tooth-surfaces-game https://www.animated-teeth.com/questions-answers/kids-tooth-anatomy/tooth-lesson-kids.html https://www.animated-teeth.com/questions-answers/dental-structures/dental-anatomy.html Practice Exercise 25

25. Summary Integrity of the tooth depends on the good health and stability of all the periodontal tissues Together, they provide and maintain the longevity of the dentition and protect it from injury