Periodontal Ligament, Alveolar Process and Cementum

1. Periodontal Ligament, Alveolar Process and Cementum DH110 ORAL HISTOLOGY AND EMBRYOLOGY Lesson 7 Tammy Fisher RDH BS

2. ROLL CALL What is your favorite food and restaurant?

3. Let’s Get Started Lesson 7 Objectives • Don’t forget the Smile Train donations! • Homework #3 graded and returned • Homework #5 part #2 returned for discussion • No homework due next week!

4. Journal Article What makes a good journal? Trade vs. Scholarly vs. Popular Ulrichsweb The Purdue Owl http://owl.english.purdue.edu/owl/ APA formatting (American Psychological Association 6th edition) Times New Roman 12 Who, When, What , and Where

6. References American Dental Association Council on Scientific Affairs (2006). The use of dental radiographs: update and recommendations. Journal of the American Dental Association, 137(9), 1304-1312. Centers for Disease Control and Prevention (2003). Guidelines for infection control in dental health-care settings-2003. Retrieved from, http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5217a1.htm Christensen, G. J. (2004). Why switch to digital radiography? Journal of the American Dental Association, 135(10), 1437-1439. Dentistry IQ (2010, September). Nomad: handheld x-ray receives accolades. Retrieved from, http://www.dentistryiq.com/index/display/articledisplay/4283591955/articles/dentisryiq/industry/2010/09/nomad-gets_innovation.html Health Physics Society (2010). Radiation exposure from medical exams and procedures. Retrieved from, http://hps.org/documents/Medical_Exposures_Fact_Sheet.pdf Standley, E. & Emmerling, H. (2011). Dental radiography: technology, infection control and exposure guidelines. RDH, 31(1), 69-73. Texas Department of State Health Services Radiation Safety Licensing Branch (2010). Guide for the preparation of operating and safety procedures for dental facilities. Retrieved from, http://www.dshs.state.tx.us/Layouts/ContentPage.aspx?PageID=35849&id=4541&terms=procedures+for+dental+facilities Wilkins, E.M. (2009). Clinical practice of the dental hygienist (10th ed.). Philadelphia, PA: Lippincott, Williams and Wilkins.

7. Quiz 3 Review Chapters 9-10 Dental Pulp and Cementum

8. Periodontium Alveolar Bone Proper Cementum Periodontal Ligament Gingiva

9. Periodontal Ligament Primary function is to support the teeth A fibrous connective tissue that attaches to the alveolar bone proper and the cementum Covers the cementum of the root and connects to the gingiva Decreases in size with age Highly cellular with vascular, neural, bone and cemental cells

11. Organization of the PDL • Gingival group = Gingival fibers • Transeptal • Attached gingival • Free gingival • Circumferential

13. Organization of the PDL • Dentoalveolar fiber group • Apical • Oblique • Horizontal • Alveolar Crest • Interradicular

18. Flash Cards • Interstitial space • An area between each group of fibers that contains a network of blood vessels, nerves, and lymphatics that maintains the vitality of the PDL.

19. Oxytalan Fibers • A type of connective tissue fibers chemically different from collagen fibers and found in the PDL and gingiva. They are elasticlike and support the vessels and fibers of the PDL.

20. Fundus or Fundic • The part of an organ that is farthest from its opening

21. Trabeculae • Small tissue elements in the form of a small beam, strut, or rod

22. Lamellae • Thin plate-like structures , often very close to one another with open space between. A thin leaf or plate, gill-like.

23. Lacunae • The very small cavities in bone that are filled with bone cells.

24. Aciniform • Fine pain receptors in the PDL. They function as a protective measure during mastication.

25. Cells of the PDL Fibroblasts Osteoblasts Cementoblasts Macrophages Osteoclasts Epithelial Rests Intercellular Tissue

26. Functions of the PDL Supportive Maintenance Sensory Nutritive

27. Aging of the Ligament Cell number and activity decrease due to diet and loss of function Scalloping occurs in cementum and alveolar bone Fibers attach to the peaks of scallops rather than entire surface of bone Good health and good oral hygiene can lead to a healthier periodontium

29. Hard Tissues of the Periodontium Alveolar Process Alveolar Bone Proper (Lamina Dura) Supporting Bone Cementum

32. Flash Cards • Fenestration • The area of alveolar bone loss where an apical root penetrates the bone.

34. Dehiscence • Alveolar bone loss in the coronal root.

36. Perforating Fibers/Sharpey’s Fibers • Penetrating connective tissue fibers by which the tooth is attached to the adjacent alveolar bone. These bundles of collagen fibers penetrate both the cementum and the alveolar bone.

38. Bundle Bone • Lamina Dura • Alveolar Bone Proper • A thin layer of hard compact bone lining the tooth sockets. Appears more dense radiographically than the adjacent supportive bone.

41. Supporting Bone Supporting Compact Bone Similar to Haversian Bone found in the body Supporting Cancellous Bone The supporting bone of the maxilla is filled with marrow tissue. Bone marrow makes up 4.5% of the body

43. Cemental Support Functions as support by attaching to perforating (or Sharpey’s)fibers Smaller and more numerous than the bundles of alveolar bone proper Cementum is more resistant to resorb than bone Cementum does not have a blood supply or nerves Cementum WILL resorb in cases of stress caused by traumatic occlusion or orthodontic treatment

44. Tooth Movement Physiologic Movement Orthodontic Movement

46. Leeway Space • The difference in the space in the arch required for the two primary molars and the successional permanent premolars replacing them. The leeway space in the maxilla is 1.3 mm and in the mandible is 3.1 mm.

47. Incisor Liability Factor • The replacement of the smaller primary incisors with larger permanent ones.

48. http://www.checkdent.com/en/videos/mesial-drift-120.html • General movement of a tooth or teeth anteriorly toward the midline of the jaw. • Mesial Drift