Contemporary Oral Maxillofacial Surgery Chapter 9 Principles of Management of Impacted Teeth (Indication & Contraindication Only)

1. Contemporary
Oral and
Maxillofacial Surgery
Chapter 9
Principles of Management of
Impacted Teeth
Textbook Reading
指導醫師：口腔外科全體
醫師
報告者：Int K 姚又勤

2. Introduction
• Impacted teeth do not erupt, which are retained
• Inadequate dental arch length and space i
• maxillary and mandibular third molars > maxillary
canines and mandibular pre-molars.
• As a general rule, all impacted teeth should be removed
unless removal is contraindicated.

3. Etiology
• During normal development, the lower third molar begins in a
horizontal angulation, and as the tooth develops and the jaw
grows, the angulation changes from horizontal to mesioangular
to vertical.
• Failure of rotation
• mesiodistal dimension of teeth versus the length of the jaw is
such that inadequate
• Average age 20 years, particularly in males, coming into final
position by age 25 years.
•

4. Space and Age
• Sufficient space
• Early removal reduces postoperative morbidity and allows
for the best healing. 2–6
• Periodontal healing and regeneration of the periodontal
tissues

5. Optimal Timepoint
• because bone is less dense and root formation is
incomplete.
• ideal time for removal of impacted third molars is when
the roots of teeth are one third formed and before they are
two thirds formed,
• Ages 17 to 20

6. Indication
• Prevention of Periodontal Disease
• Prevention of Dental Caries
• Prevention of Pericoronitis
• Prevention of Root Resorption
• Impacted Teeth under Dental Prosthesis
• Prevention of Odontogenic Cysts and Tumors
• Treatment of Pain of Unexplained Origin
• Prevention of Jaw Fractures
• Facilitation of Orthodontic Treatment

7. Prevention of
Periodontal Disease
• Decreases the amount of bone
• Gingival inflammation with
apical migration and deep
periodontal pockets
• Especially serious in maxilla.
• involve distal furcation of the
maxillary second molar.

8. Prevention of Dental
Caries
• distal aspect of the second
molar and impacted third
molar.
• which no obvious
communication between the
mouth and the impacted third
molar exists,

9. Prevention of Dental
Caries

10. Prevention of
Pericoronitis
• Infection of soft tissue around partially impacted tooth
• Operculum can be traumatized and become swollen.
• Trauma and swelling often interrupted only by removal of
maxillary third molar
• Entrapment of food under the operculum

11. Pericoronitis
• Figure 9-6 Pericoronitis in
area of impacted tooth #48
exhibiting classic signs of
inflammation with erythema
and swelling.

12. Initial Tx
• Treated initially by mechanically debriding by using
hydrogen peroxide or Saline solutions
• Mild infection, irrigation and curettage

13. Severe Condition
• Severe Condition : traumatized by maxillary third molar
• Severe Condition :
• Facial swelling
• Mild trismus resulting from inflammation extending
into the muscles of mastication
• Low-grade fever

14. Prevention of
Pericoronitis
• Patient should be informed that the tooth should be
removed to prevent recurrent infections.

15. Prevention of Root
Resorption

16. Impacted Teeth under
Dental Prosthesis
• After teeth extracted, alveolar process resorp
• Impacted tooth becomes closer to the surface
• Compress soft tissue onto impacted tooth
• Ulceration

17. Prevention of Odontogenic
Cysts and Tumors
• Follicular sac is frequently
retained.
• May undergo cystic
degeneration
• Follicular space around crown
> 3 mm

18. Treatment of Pain of
Unexplained Origin
• Retromolar region pain
• Etiology not obvious.
• Myofascial pain dysfunction and facial pain disorders
excluded
• Sometimes results in resolution of the pain

19. Prevention of Jaw
Fractures
• An impacted third molar in the
mandible occupies bone space.

20. Facilitation of
Orthodontic Treatment
• Retraction of first and second molars
• Placement of retromolar implants

21. Optimal Periodontal
Healing
• Preserve the periodontal health of the adjacent second
molar
• Optimal periodontal tissue healing depends on
• the extent of the preoperative infrabony defect
• patient’s age （ < 25 y/o )

22. Optimal Periodontal
Healing
• Asymptomatic completely bony impacted third molar
• > 30 years

23. Summary
• Prevention of Periodontal Disease
• Prevention of Dental Caries
• Prevention of Pericoronitis
• Prevention of Root Resorption
• Impacted Teeth under Dental Prosthesis
• Prevention of Odontogenic Cysts and Tumors
• Treatment of Pain of Unexplained Origin
• Prevention of Jaw Fractures
• Facilitation of Orthodontic Treatment

24. Contraindication
• Age
• Compromised Medical Status
• Probable Excessive Damage to Adjacent Structures

25. Age
• Impaction retained in alveolar process for many years
without periodontal disease, caries, or cystic degenera-tion
• Unlikely unfavorable sequelae occur
• 1 or 2 years interval F/U

26. Compromised Medical
Status
• If impacted tooth asymptomatic
• surgical removal elective

27. Compromised Medical
Status
• If symptomatic
• Working with physician to get a treatment plan

28. Probable Excessive Damage
to Adjacent Structures
• Jeopardize adjacent nerves, teeth, or previously
constructed bridges
• Weighed against potential future complications.

29. Summary
• First, the available room in the arch ︖
• Status of the impaction and age of the patient
• 20 and 25

30. Thanks for your
attention !