1. IN THE NAME OF GOD Dr:Nahvi Force eruption

2. Unerupted tooth Fractured tooth

3. Tooth eruption A permanent tooth should erupt: 6 months after natural exfoliation of its predecessor Eruption delayed : if the interval extends to more than 1 year.

4. Eruption of a tooth is considered to be delayed : The normal time for eruption has been exceeded. The tooth is not present in the dental arch and shows no potential for eruption. The root of the unerupted tooth is completely formed. The homologous tooth has been erupted for at least 6 months. J Can Dent Assoc 2010

5. Most commonly become impacted third molars maxillary canines maxillary central incisors mandibular second premolars

6. Causes of Delayed Eruption Localized Generalized

7. Localized the presence of supernumerary teeth (most common ) Odontoma dilaceration malpositioning of the tooth germ Crowding calcifying odontogenic cyst trauma to the corresponding deciduous tooth

8. systemic conditions cleidocranial dysostosis hypothyroidism Gardner syndrome Down syndrome

9. Criteria for Treatment chief complaint At least 3 mm of bone The tooth is mature J Can Dent Assoc 2010;76:a147

10. Alignment of an impacted tooth position and direction degree of root completion degree of dilacerations presence of space

11. Treatment planning: 1-surgical exposure 2-Attachment to the tooth 3-Orthodontic mechanics

12. surgical exposure (1) exposure of the entire labial aspect (the window approach) (2) a technique which exposes only 4–5 mm of the labial aspect

13. Attachment Gold chain Band Cast gold crown,onlay Threated pin Wire loop Direct bond attachment(the best)

14. General characteristics of orthodontic Forces Optimal:light,continuous -Ideal material Maintains elasticity Maintains force over a range of tooth movement

15. Force Continuous Interrupted Intermittent Extrusion 35-60gr

16. Continuous

17. Interrupted

18. Intermittent

19. Contemporary orthodontics

20. Direction of force parallel to the long axis avoid torquing forces Oral Maxillofacial Surg Clin N Am 16 (2004) 75-89

21. Force eruption Fixed appliances Removable appliances

22. Fixed appliances  Do not require special patient cooperation  precise coronal and root movements Removable appliances  less chairtime  better oral hygiene  More esthetic

23. Removable appliances retention clasps labial bow Hook(for attachment of elastics) Finger spring,Zspring,Canine retractor

24. Removable appliances at least 10 hours per day. Rest intervals,not to exceed five hours per day. wear the appliance 24 hours a day, removing it only for meals

25. the elastics should be changed every two or three days. Lingual tipping will be minimized when the labial bow is used for the extrusive force JCO/JULY 2002

27. Fixed appliances coil : maintains the space anchorage and balancing resistance J Can Dent Assoc 2010

28. Anchorage support for the extrusion—a minimum of one tooth on either side of a single-rooted tooth (2 anchors) or two teeth on either side of a multi-rooted tooth (4 anchors) Use a heavy square or rectangular NiTi wire to minimize tipping

29. J Can Dent Assoc 2010;76:a147

30. Magnetic force For a patient with other missing teeth Contemporary orthodontics

31. Elastics -light -medium(1/8 =3.18mm 127.58gr) -heavy Orthodontic Elastics (3/8", 5/16", 1/4", 3/16", 1/8") Shiraz Univ Dent J 2009; 10(1):7-15

32. clinical problems (canine) 1) Lateral root resorption 2) External cervical resorption 3) Dentoalveolar ankylosis 4) Calcific metamorphosis of the pulp and aseptic pulp necrosis. Dental Press J Orthod. 2010 Nov-Dec;15(6):18-24

34. Thank You