mandibular wisdom teeth, oral and maxillofacial surgery ;peri operative surgical management of impacted third molars

1. Peri-operative Management
of Impacted Third Molars
Dr Chamara Atukorala MD
Consultant Oral and Maxillofacial Surgeon

2.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

3.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

4. Impacted tooth is a one that has not erupted to its
functional position in the occlusion and does not
show clinical or radiological features indicating
that it may erupt.
Causes
• Angulation
• Hard or soft tissue obstruction
• Pathological lesions
• Lack of space

5.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

6. The management of asymptomatic, disease-free ITM
is controversial, the best evidence currently available
neither supports nor refutes extraction .
(Symptomatic ITM?)
Available Guidelines
Local- None
Foreign
NICE
AAOMS
What is a Guideline ?

8. Guidance
1.1 The practice of prophylactic removal of pathology-free ITM should be
discontinued .
1.2 The standard routine programme of dental need be no different.
1.3 Surgical removal of ITM should be limited to patients with evidence
of pathology. Such pathology includes unrestorable caries, non-treatable
pulpal and/or periapical pathology, cellulitis, abcess and osteomyelitis,
internal/external resorption of the tooth or adjacent teeth, fracture of
tooth, disease of follicle including cyst/tumour, tooth/teeth impeding
surgery or reconstructive jaw surgery, and when a tooth is involved in or
within the field of tumour resection.
1.4 The evidence suggests that a first episode of pericoronitis, unless
particularly severe, should not be considered an indication for surgery.

9. The Guidelines boil down to waiting for some
pathology to develop, (such as decay in the wisdom tooth or the
adjacent tooth, gum disease around the wisdom tooth,infection around the
tooth crown, cellulitis, abscess and including cyst / tumour,tooth / teeth
impeding surgery or reconstructive jaw surgery )
Why Do British Practice This ?
This is regarded by some as supervised
neglect.

10. The American Association of Oral & Maxillofacial Surgeons (AAOMS), the
professional organization representing more than 8,500 OMF surgeons in
the USA .
• “Asymptomatic” does not mean “Disease Free ” Pathology is always
present before symptoms appear. Once damage has occurred, it is not
always treatable
• 25% of wisdom teeth patients who perceive themselves as asymptomatic
actually already have inflammatory periodontal disease. Blakey GH, Marciani
RD, Haug RH, et.al: Periodontal pathology associated with asymptomatic third molars;
Journal of Oral and Maxillofacial Surgery. 2001;60:1227-1233

11. • The risk of future disease requiring removal of retained wisdom teeth in
asymptomatic patients who retain their wisdom teeth, exceeds 70%
after 18 years of follow-up. Venta I, Ylipaavalniemi P, Turtola L: Clinical outcome of
third molars in adults followed during 18 years. J Oral Maxillofac Surg. 62:182, 2004
• 20 years after UK adopts the “National Institute of Clinical Excellence”
(NICE) guidelines, volume of third molar surgeries decrease, with a
corresponding increase in mean age for surgical admissions and an
increase in “caries” and “pericoronitis” as etiologic factors. Renton T, Al-
Haboubi M, Pau A, Shepherd J, Gallagher JE: What has been the United Kingdom’s experience
with retention of third molars? J Oral Maxillofac Surg. 70:48-57, 2012, Suppl 1
• Retention of third molars is associated with increased risk of second
molar pathology in middle-aged and older adult men. Nunn, ME, et al.
Retained Asymptomatic Third Molars and Risk for Second Molar Pathology. Nunn et al. J DENT
RES published online 16 October 2013.
AAOMS firmly supports the surgical management of erupted and
impacted third molar teeth, even if the teeth are asymptomatic, if there
is presence or reasonable potential that pathology may occur caused by
or related to the third molar teeth. November 10, 2011

12. Indications for removal of ITM identified in the Parameters
and Pathways published by the AAOMS include
1. Pain , 2. Carious tooth , 3. Pericoronitis
4. Facilitation of the management of progression of periodontal disease
5. Nontreatable pulpal or periapical lesion
6. Acute and/or chronic infection (e.g., cellulitis, abscess)
7. Ectopic position (malposition, supraeruption, traumatic occlusion)
8. Abnormalities of tooth size or shape precluding normal function
9. Facilitation of prosthetic rehabilitation
10. Facilitation of orthodontic tooth movement and promotion of stability of
the dental occlusion
11. Tooth in the line of fracture complicating fracture management
12. Tooth involved in surgical treatment of associated cysts and tumors

13. 13. Tooth interfering with orthognathic /or reconstructive surgery
14. Preventive or prophylactic removal, when indicated, for patients with medical
or surgical conditions or treatments (e.g., organ transplants, alloplastic implants,
bisphosphonate therapy, chemotherapy, radiation therapy)
15. Clinical findings of pulp exposure by dental caries
16. Clinical findings of fractured tooth or teeth Impacted tooth
18. Internal or external resorption of tooth or adjacent teeth
19. Patient’s informed refusal of nonsurgical treatment options
20. Anatomic position causing potential damage to adjacent teeth
21. Use of the third molar as a donor tooth for tooth transplant
22. Tooth impeding the normal eruption of an adjacent tooth
23. Resorption of an adjacent tooth
24. Pathology associated with the tooth follicle
25. Abnormality of size or shape precluding normal function

15. When managing a patient with asymptomatic,
disease-free ITM, one must carefully review the
risks and benefits of extraction or retention, and
heavily weight the patient’s treatment
preference.

16. “A strong indication for removal of
impacted third molar should be
complemented with a strong
contraindicationtoitsretention”
– Mercier P., Precious D., Risk and benefits of removal of impacted third
molars, IJOMS 21:17, 1992.

17.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

18. Radiological Investigations
 Radiographs
Intra Oral
IOPA
Occlusal views
Extra Oral
DPT (OPG)
Lateral Oblique Views
 CT
Cone Beam CT
Conventional CT

20. Radiological Assessment Helps In
 Classification of the ITM
 Localisation and orientation of the ITM
 Assessment of the crown and root morphology of
the ITM
 Assessment of the ramal bone cover
 Assessment of the second molar tooth and its root
morphology
 Relationship of the ID canal to the roots of ITM
 Associated pathological lesions with the ITM

21.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

22. Systematic classification of the position of
Impacted Third molar ( ITM) teeth helps in
– Assessing the best possible path of removal of the
ITM
– Managing difficulties encountered during removal

23. Prediction of operative difficulty before the extraction
of ITM allows a design of treatment that minimises
the risk of complications.
Both radiological and
clinical information must be taken into account.

24. Classification of Impacted Mandibular 3rd
Molars
1. ADA-AAOMS Classification
2. Nature of the overlying tissues
3. Winter’s Classification
4. Pell & Gregory’s Classification

25. ADA-AAOMS Classification
 Impacted tooth-with overlying soft tissue.
 Impacted tooth-Partial bony impaction.
 Impacted tooth-complete bony impaction .
 Impacted tooth-complete bony impaction with unusual
surgical complications.

26. Nature of the overlying tissues
 Soft Tissue Impaction. is usually the
easiest of type of impacted tooth to remove.
 Hard Tissue ('Bony') Impaction.
– Partial Bony. The superficial portion of the tooth is
covered only by soft tissue but the height of the
tooth's contour is below the level of the surrounding
alveolar bone.
– Complete Bony. The tooth is completely encased in
bone so that when the gingiva is cut and reflected
back, the tooth is not seen. These are often the most
difficult tooth to remove

27. Winter's Classification
 Mesioangular - 45%
 Vertical - 40%
 Horizontal - 10%
 Distoangular – 5%
 Inverted
• Bucco-version
• Linguo-version
• Transverse

30. Pell & Gregory's Classification
Based on the relationship between the ITM to the ramus of the
mandible (lower jaw) and the 2nd molar (based on the space
available distal to the 2nd molar).
Class A. The highest portion of impacted 3rd molar is on a level
with or above the occlusal plane.
Class B. The highest portion of impacted 3rd molar is below the
occlusal plane but above the cervical line of the of 2nd molar.
Class C. The highest portion of impacted 3rd molar is below the
cervical line of the of 2nd molar.

33.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

34. Assessment
Case history
General medical status of the patient ( Fitness to undergo ITM
surgery)
Extra oral examination
Mouth opening and TMJ
Facial form, mental nerve functioning
Intra oral
Surgical site
ITM in question
 Assessment of the degree of difficulty of the ITM
surgery
Assess the radiological features

36. Assessment of the degree of difficulty of
the surgery
WAR (Winter’s) Lines
WHARFE’s ASSESSMENT by McGregor (1985)
PEDERSON’S DIFFICULTY INDEX

37. Category Score
1. Winters
classification
Horizontal
Distoangular
Mesioangular
Vertical
2
2
1
0
2. Height of mandible 1-30mm
31-34mm
35-39mm
0
1
2
3. Angulation of 3rd
molar
1° - 50°
60° - 69°
70° -79°
80° - 89°
90°+
0
1
2
3
44. Root shape Complex
Favourable curvature
Unfavourable curvature
1
2
3
5. Follicles Normal
Possibly enlarged
Enlarged
0
1
2
6. Exit (Path of exit) Space available
Distal cusp covered
Mesial cusp covered
Both cusp covered
0
1
2
3
Total 33
WHARFE’s
ASSESSMENT by
McGregor (1985)

38. PEDERSON’S DIFFICULTY INDEX
• Very difficult : 7 to 10
• Moderataly difficult: 5 to 7
• Minimally difficult : 3 to 4
Scoring
Mesio angular 1
Horizontal 2
Vertical 3
Distoangular 4
Level A 1
Level B 2
Level C 3
Class I 1
Class II 2
Class III 3

39. Radiological features indicating a close association
between IAN and ITM

42. If the ID nerve is closely associated indicating a
high risk of injury ; best is to assess using
advanced imaging methods
 Cone Beam CT
 Conventional CT

45. Important Anatomical Structures

46.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

47. ITM Management options
*Observation and periodic review
*Surgery
**Conventional
***Intra Oral
****Buccal Approach
****Lingual Split Technique
****BSSO
***Extra Oral Approach
• **Coronectomy
• ** Staged Removal

50. Planning

51. Observation and periodic review
For patients who elect retention, the frequency of follow
ups should be designed to match the symptoms or
disease associated with ITM
( physical and radiographic examination every 12 to 24
months by a health care professional trained to evaluate
third molars.)

52. Surgery
Set up of care
LA +/- sedation
GA

53.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

54. Steps In Surgical Removal
(Buccal Access)
Anesthesia
Incision and mucoperiosteal flap design and flap
reflection
Removal of bone
Sectioning of tooth/roots
Elevation/Extraction
Wound debridement and smoothening of bone
Achieve Haemostasis
Wound closure, Analgesics
Postoperative follow-up

56. Principles of flap design
Adaquate access
Viability of the flap ( Base> top)
Avoid vital structures
Plan ease of repositioning
Ability to extend if the need arises
Clean incisions

57. Types of flap designs
• Envelope flap
• L- shaped incision
• Bayonet shaped incision
• Triangular shaped incision
• Ward’s incision and Modified Ward’s incision.
• Comma shaped incision.
• S -shaped incision
• Szmyd and modified Szmyd incision
• Berwick’s tongue shape flap.

58. Ward’s incision
Modified Ward’s

59. Envelop flap
Incision Not to be extended
too distally-
 Bleeding from buccal vessels &
other arteries
 Postoperative trismus – temporalis
muscle damage
 Herniation of buccal fat pad
 Damage to lingual nerve (lingual
extention)

60. Triangular shaped Incision

61. Bone Removal
“Bone belongs to the patient
and tooth belongs to the
dentist”
 Minimize the amount of bone removal as possible
 Instead section the tooth and deliver in pieces
 Excessive bone removal results in poor healing and
bone defect.
 High risk of alveolar osteitis, post op pain and
trismus.

62.  Once the soft tissue is elevated and retracted, the
surgeon must make a judgment concerning the amount
of bone to be removed.
 Bone must be removed in an atraumatic, aseptic, and
non–heat-producing technique, with as little bone
removed and damaged as possible.
 The amount of bone that must be removed varies with
the depth of impaction, the morphology of roots, and the
angulation of tooth.
 No bone should be removed from lingual aspect so as to
protect the lingual nerve from injury.

63. Bone removal - Moore & Gillbe’s Collar
Technique

64. Tooth Division
“Rationale of tooth sectioning is to create
a space into which impacted tooth can be
displaced & thence removed.”
Tooth is sectioned in various ways depending on the type &
degree of impaction.
Tooth is sectioned ¾ of the way
towards the lingual aspect. A straight elevator is inserted
into the slot made by the bur and rotated to split the tooth

74. Extra Oral Approach

75. SSO

77. Coronectomy

79. Coronectomy
What is it ?
Indications
Technique
Post op Mx
Follow up

81. Staged Removal

82. Debridement of Wound & Closure
• Thorough debridement of the socket by Periapical curettage.
• Remove the follicle of the ITM.
• Smoothening of sharp bony margins by Bone file / burs.
• Thorough irrigation of the socket Betadine solution + Saline .
• Initial wound closure is achieved by placing 1stsuture just
distal to 2ndmolar, sufficient number of sutures to get a
proper closure.

83.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

84. Post Operative Instructions
• Pressure pack , Ice application
• Soft diet –1st two days
• 1st dose of analgesic should be taken before the
anesthetic effect of LA wears off.
• Avoid strenuous exercises for 1st 24 hrs.
• Avoid gargling / spitting / smoking / drinking
with straw.
• Warm water saline gargling after 24 hrs + mouth
wash regularly thereafter.
• Suture removal on 5th POD.

85. Antibiotics ?
Steroids?

86.  Definition
 Prevalence
 Indications for Surgical removal, /Guidelines
 Investigations and Diagnosis
 Classification
 Surgical management
Assessment
Planning
Execution
 Post op Management
 Complications and their Management
 Medico-legal Background

87. Complications and their Management
Intra Operative
1. During incision
a. Injury to facial artery
b. Injury to lingual nerve
c. Hemorrhage – careful history
2. During bone removal
a. Damage to second molar
b. Slipping of bur into soft tissue & causing injury
c. Extra oral/ mucosal burns
d. Fracture of the mandible when using chisel & mallet
e. Subcutaneous emphysema

88. 3. During elevation or tooth removal
a. Luxation of neighbouring tooth/
fractured restoration
b. Soft tissue injury due to slipping of elevator
c. Injury to inferior alveolar neurovascular bundle
d. Fracture of mandible
e. Forcing tooth root into submandibular space or
inferior alveolar nerve canal
f. Breakage of instruments
g. TMJ Dislocation – careful history

89. Post-operative complications
• Immediate
- Hemorrhage
- Pain
- Edema
- Drug reaction
• Delayed
- Alveolitis
- Infection
- Trismus

90. From Medico-legal point of view to avoid
getting in to problems.
• Make correct decisions
• Get patient actively involved in
decision making
• INFORMED CONSENT
• Proper investigations
• Correct treatment.
• Manage complications
• Communicate with the patient
• Be nice to your patient