Impaction

IMPACTION
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1
DR. SWATI SAHU
MDS FELLOW
DEPT. OF ORAL & MAXILLOFACIAL SURGERY

CONTENT
 Introduction & etymology
 Definition
 chronology
 Theories of tooth impaction
 Etiology
 Surgical Anatomy of 3rd molar
 Indications and contraindications
 Mandibular 3rd molar: classification
pre–op assessment
various incision
removal of tooth
complications
 Mandibular canine
 Mandibular 2nd molar
 Mandibular premolar
 Mandibular incisor
 References
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INTRODUCTION
 The management of impacted teeth is a basic component of most oral and maxillofacial surgery
practices.
 Although the majority of impacted teeth are third molars, any other tooth may be impacted.
 The usual care for impacted third molars is removal; however, the care for impacted teeth other than third
molars may include exposure (with or without attachment of an orthodontic bracket), uprighting,
transplantation, or removal. These teeth often pose challenges in treatment planning and surgical care
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ETYMOLOGY
 They are generally thought to be called wisdom teeth because they appear so late – much later than the
other teeth, at an age where people are presumably "wiser" than as a child, when the other teeth erupt.
The term probably came as a translation of the Latin dens sapientiae.
 Wisdom teeth usually appear between the ages of 17 and 25. a time of life that has been called the
"Age of Wisdom”.
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 Impacted tooth is a tooth which is completely or partially unerupted and is
positioned against another tooth, bone or soft tissue so that its further eruption is
unlikely, described according to its anatomic position.
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Malposed tooth is tooth, unerupted / erupted which is in an abnormal position in the
maxilla/mandible

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 Unerupted tooth is a tooth not having perforated the oral mucosa

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Ankylosed teeth is when cementum of the tooth is fused to the alveolar bone and there is no
periodontal ligament in between, a tooth is considered to be ankylosed

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Partially erupted when the tooth has failed to erupt into a normal functional position but has
crossed the bone barrier and has not reached the occlusal line.

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Ectopic/displaced teeth a tooth is ectopic if malpositioned due to congenital factors or
displaced by the presence of pathology.

DEFINITION
BY ARCHER –
“A tooth which is completely or partially unerupted beyond its chronologic age & is positioned against
another tooth, bone or soft tissue, so that further eruption is not possible is known as impaction”
ANDERSSON (1997) , FONSECA (2000) ,PETERSON & LASKIN
Impaction is defined as a cessation of eruption of a tooth caused by a clinically or radio graphically
detectable physical barrier in the eruption path or by an ectopic position of the tooth.
SHAFER-
Impacted teeth are those prevented from erupting by some physical barrier in the eruption path
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AMERICAN SOCIETY OF ORAL SURGEONS 1971
A tooth which is completely or partially unerupted and is positioned against another tooth, bone or soft
tissue so that its further eruption is unlikely, described according to its anatomic position.
LYTLE: --
Impacted tooth is one that has failed to erupt into normal functional position beyond the time usually
expected for such experience. Eruption is prevented by adjacent hard or soft tissue including
tooth, bone, of dense soft tissues.

11 year 14 year
18 year 25 year
Tooth germ -9 year
Cusp mineralization -2 year later
11 year- tooth located in anterior border of
ramus, occlusal surface facing anteriorly
Crown formation-14 years
Root-50% formed by 16 years
Root formation with open apex-18 years
24 years-95% of 3rd molars completed
eruption
chronology
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THEORIES OF IMPACTION
(ACCORDING TO DURBECK)
 Phylogenic Theory
 Mendelian Theory
 Endocrine Theory
 Orthodontic Theory
 Skeletal Theory
 Anthropological Theory
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www.indianjournals.com/%2Fijor.aspx?target=ijor:rjpt&volume=7

PHYLOGENIC THEORY
 Nature tries to eliminate that which is not used.
 Third molar occupies an abnormal position and may be considered as a vestigial
organ without purpose or function
• Individual receives small jaw from one parent and complement of large teeth from another parent.
Mendelian Theory
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ENDOCRINE THEORY
 Lack of growth of the jaws is due to the lack of the function of the anterior lobe of the pituitary
gland with the result that sufficient amount of growth hormone is not produced to ensure the
proper growth of jaws.
Orthodontic Theory
 Constricted and narrow dental arches of early mouth breathers affect the position and alignment
of permanent teeth.
 The third molars attempting to erupt at a time when the deformity is well established gets
impacted.
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SKELETAL THEORY
 Inadequate growth of the jaws due to an improper function of the functional matrix in which it is
enclosed leads to lack of space for eruption of the third molars.
Anthropological Theory
 During the course of evolution, increase in cranial capacity occur at the cost of decreasing jaw size
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ETIOLOGY
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LOCAL
CAUSES
SYSTEMIC
CAUSES
ACCORDING
TO
BERGER

ETIOLOGY – LOCAL CAUSES
 Obstruction for eruption
 Irregularity in position and presence of an adjacent tooth
 Density of overlying and surrounding bone
 Lack of space in dental arch
 Supernumerary teeth
 Crowding
 Ankylosis of primary or permanent teeth
 Over-retention of deciduous teeth
 Dilaceration of roots (trauma)
 Habits involving
 Tongue
 Finger
 Thumb
 Cheek
 Pencil Etc
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ETIOLOGY – SYSTEMIC
CAUSES Prenatal Causes
 Heredity
 miscegenation
 Post Natal Causes
 Rickets
 Anemia
 Tuberculosis
 Congenital Syphilis
 Malnutrition
 Endocrinal disorders of
 Thyroid
 Parathyroid
 Pituitary Glands disorders
like
 Hypothyroidism
 Achondroplasia etc
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 Hereditary Linked disorders
like
 Down’s Syndrome
 cleidocranial dysostosis
 Hurler’s Syndrome
 Osteoporosis
 oxycephaly
 Cleft Palate Etc.

cleidocranial dysostosis
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oral surg. oral med. oral pathol. 59~420-
425, 1985
ACCORDING TO ARCHER IMPACTED TEETH OCCUR IN THE
FOLLOWING ORDER OF FREQUENCY.
 Maxillary 3rd molars.
 Mandibular 3rd molars.
 Maxillary cuspids.
 Mandibular bicuspids.
 Mandibular cuspids.
 Maxillary bicuspids.
 Maxillary central incisors.
 Maxillary lateral incisors.
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RECENT
 Mandibular 3rd molars
 Maxillary 3rd molars
 Maxillary canine
 Mandibular canine
 Mandibular premolar
 Maxillary premolar
 Maxillary central incisors
 Maxillary lateral incisor

INDICATIONS
Sequelae of impaction
• Pericoronitis
• Caries
• Periapical Pathosis
• Focus Of Infection
• Anterior Crowding
• Retention Or Resorption Of 2nd Molar(pathologic Resorption)
• Increased Risk Of Angle Fracture
• Cyst And Tumors
• Facial Pain 14-04-2018 23

OTH
ER
 Periodontal Consideration
 Orthodontic Consideration
 Prosthodontic Consideration
 Involvement In Fracture Line
 Retention of 2nd Molar
 Orthognathic Surgery
 Prophylactic Removal
RETENTION OF 14-04-2018 24

PERICORONITS CARIES
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PERIAPICAL
PATHOSIS
PATHOLOGIC
RESORPTION
FORMATION OF
FOLLICULAR CYST
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CONTRAINDICATIO
NS
 Deeply, embedded, asymptomatic impacted molar.
 Poor systemic condition of patient
 Poor prognosis of 2nd molar.
 In case it can serve as abutment tooth.
 Extremes of age
 Question about the future status of the second molar
 Probable Excessive Damage to Adjacent Structures
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SURGICAL ANATOMY
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Relation with:
• lingual nerve
• long buccal nerve
• Inferior dental nerve
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CLASSIFICATION OF
IMPACTED MANDIBULAR
THIRD MOLAR
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Angulation
Impacted tooth
2nd MolarInferior alveolar canal
Thickness
of bone
Depth of impaction
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Classification Of Impacted Mandibular 3rd Molar Teeth
Winter’s classification(1926):---Angulation
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G.R.OGDEN METHOD
It compares the distance between
the roots of 2nd & 3rd molars with
that of 1st & 2nd molars

MODIFIED WINTER CLASSIFICATION-
(ARCHER, 1966):
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Pell and Gregory’s classification (1933)
Relationship of impacted third molar to ramus of mandible and second molar based on space available
distal to second molar
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PELL AND GREGORY’S
CLASSIFICATION(1942)
 Depth :- based on relationship to the occlusal plane of impacted tooth to that of second
molar
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Combined ADA and AAOMS
Classification for Impacted Teeth
 07220 :-overlying soft tissue (Impaction that requires incision of overlying soft tissue and the removal of
the tooth)
 07230 : -partially bony impacted (Impaction that requires incision of overlying soft tissue, elevation of a
flap, and either removal of bone and tooth or sectioning and removal of tooth)
 07240: -completely bony(Impaction that requires incision of overlying soft tissue, elevation of a flap,
removal of bone,and sectioning of tooth for removal)
 07241: -completely bony, with unusual complications (Impaction that requires incision of overlying
soft tissue,elevation of a tlap, removal of bone, sectioning of the tooth for removal, and/or presents
unusual difficulties and circumstances)
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1.Position & Angulation- Winter’s Classification
a) Erupted
b) Partly erupted
c) Unerupted
3. Number & pattern of roots
- Fused
-Multiple
-Favourable
-Unfavourable
2. State of eruption
-Two
KILLEY & KAY’S
CLASSIFICATION

BASED ON STATE OF
ERUPTION
Erupted
Partially Erupted
Unerupted
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BASED ON NUMBER
OF ROOTSFused Roots
Two Roots
Multiple Roots
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BASED ON TYPE OF TISSUE OVERLYING THE TOOTH
Soft Tissue
Partial Bony
Complete Bony impaction
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NEW CLASSIFICATION (2013)

14-04-2018 44J Oral Maxillofac Res. 2013 Apr-Jun; 4(2): e1

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CBCT RADIOLOGICAL CLASSIFICATION FOR
MANDIBULAR 3rd MOLARS

PRE-OPERATIVE
ASSESSMENT OF
IMPACTED MANDIBULAR
THIRD MOLARS
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Assessment of impacted tooth is done
1. History
2. Clinical evaluation
3. Radiographic evaluation

HISTORY
 Age
 General medical condition
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CLINICAL EXAMINATION
 Mouth opening
 Absence of local inflammatory conditions
 Determination of mobility characteristics of lips and cheeks
 Size and contours of the tongue
 Appearance of soft tissue overlying the impacted teeth
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RADIOGRAPHIC
EVALUATION
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SHOWS :
 Position and type of impaction.
 Relationship of impacted tooth to adjacent teeth.
 Size and shape of impacted tooth.
 Depth of impaction in bone.
 Density of bone surrounding impacted tooth .
 Relationship of the impacted tooth to various anatomic structures.
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Radiographic evaluation
A.INTRA-ORAL
1. Periapical (IOPA) x-ray – paralleling tech./distal oblique/bisecting
2. Bitewing x –ray
3. Occlusal x-ray – topographical/cross-sectional/modified lateral cross- sectional
Projection
B.EXTRA-ORAL
1. Lateral oblique mandible x-ray
2. Orthopantomogram
3. Computed tomography
4. Cone- beam CT scan
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PERIAPICAL RADIOGRAPHS

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According to winter (1926)
An ideal periapical X-ray should include
1. the whole third molar,
2. its investing bone,
3. the anterior border of ramus,
4. the inferior alveolar canal and
5. the adjacent second molar tooth.
• In a good film the lateral image of the second molar will be sharp without vertical shortening.
• In a poor film with incorrect angulation, the 'enamel cap' will be absent and there will be
overlapping of contact points of molars.
A. L. Mac Gregor, Geoffrey Hoe, Killey And Kay, Archer

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The specifications for an ideal IOPA radiograph as per G. B. Winter (Mac GREGOR)
• The buccal and lingual cusps of the erupted second molar must be
superimposed
• The area of contact of first and second molar must not show overlap.
• The film must be far enough back in the mouth to show only the distal root of the
first molar.
• The whole third molar should be seen.
According to G.L.Howe the standard IOPA must have typical ‘enamel cap’
appearance of second molar.

A. Root morphology
 The number of factors considered.
a) Length of the root - Optimal time is when the roots 1/3 +2/3 formed. When this is the
case, the ends of the roots are blunt and almost never fracture.
If the root development is insufficient less than 1/3of the tooth, it is difficult to remove.
b) Single/conical, separate/distinct roots are noted.
c) Curvature of roots
d) Total width of the roots in mesiodistal direction should be compared with the width of the
tooth at the cervical line.
e) Assess the periodontal ligament space. More the width the periodontal ligament space,
is the easier the tooth is to remove. 14-04-2018 60

B. Size of follicular sac
More follicular space
Less alveolar bone
Easy removal
C. Density of the surrounding bone
 Younger patient the bone is less dense, is more likely pliable and expands and blends
somewhat, which allows the socket to be expanded by elevators/by luxation forces by itself
and easier to cut with bur.
 Patients who are older than 35 years have dense bone and thus decreased ability to
expand. In these patients surgeon must remove all interfering bone, because it is not
possible to expand the bone socket. Bone cutting is difficult and bone removal process
takes longer.
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D. Contact with the 2nd molar
• Taken care if 2nd molar has carious/large restoration/root canal treated.
• Locked against second molar there is no space for elevation, then sectioning of the tooth should be
planned.
E. Nature of overlying tissues -is considered
• Soft tissue covering
• Soft tissue + Bone covering
• Bone

F. Inferior Alveolar Nerve and Vessels
 Are usually in true osseous canal in the ramus and body of the mandible. There may be
multiple branches of Inferior Alveolar Nerve, instead of single combined structure. When
Inferior Alveolar Nerve canal identified radiograhically, determine its relationship with
impacted mandibular 3rd molar. Usually canal will be inferior/buccal to the third molars,
but variations are common.
 Blending of the structure radiographically indicates that the root surround the canal and
its contents
 A thinning/narrowing of canal indicates displacement of the canal by the roots of the
tooth. 14-04-2018 64

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• Distinct lines of canal and of roots indicate an overlap
without encroachment.
• To locate the canal, Frank suggests that a modification of tube shift method can be used to
determine whether mandibular canal is medial to, lateral to/below an impacted mandibular 3rd
molar. This method first described by Richards.
• Two films in identical position used but position of the x-ray tube changed to determine the
position of impacted teeth.
• To accomplish this an x-ray angle must be shifted from 25 degree upwards and this 2nd film
compared with the film taken with the x-ray tube parallel to occlussal plane.

RELATIONSHIP OF INFERIOR ALVEOLAR NERVE TO THE ROOTS OF THE
THIRD MOLAR.
Deflected roots
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G. LINGUAL NERVE
 The studies by Kisselbach and Chamberlain demonstrated that the lingual nerve may be
located some time slighter superior to the crest of bony ridge medial to the mandibular 3rd
molar region and only 1/2mm toward midline in the lingual soft tissue. At this position
lingual nerve is at risk during flap reflection.
 Usual location is superior and inferior to mylohyoid muscle. The nerve may be in various
locations from crest of alveolar process to positions below mylohyoid muscle.
 More than one branch of the nerve may be present, and the position of the lingual nerve,
relative to the mandibular 3rd molar may vary depending on the intersection of the body of
the mandible and the ramus.
 The lingual nerve is relatively more superior and more directly associated with the soft
tissue immediately adjacent to the mandible and hence greater chance of damage during
surgery, in the class III and II relationships than in the class I . 14-04-2018 68

H. Relationship to Body and ramus of mandible is important surgical consideration. This
relationship described by Gregory and Pell.
 In Class III, the ramus begins immediately posterior to 2nd molar and no space consists for the impacted
tooth to erupt.
 In class II and class III relation there is reduced surgical access and close anatomic relationship with
lingual nerve exists.
I. Third molar and 2nd molar relationship
 The long axis of the third and 2nd molar is studied to determine whether impacted tooth is in
Mesioangular/ Vertical/Distoangular/Horizontal/inverted position.
 The level of the crown of third molar are determined whether it is crown to crown, crown to cervix, crown
to root and crown below 2nd molar.
J. Buccal to lingual position of third molar
If impacted 3rd molar is too lingually placed there may be chance of stretching of the lingual nerve.
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Mandibular Molar
External oblique ridge
Mylohoid ridge
Mandibular canal
Submandibular
fossa
ab
c
dd
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External oblique ridge. A continuation of the anterior border of the ramus, passing
downward and forward on the buccal side of the mandible. It appears as a distinct
radiopaque line which usually ends anteriorly in the area of the first molar. Serves as an
attachment of the buccinator muscle. (The red arrows point to the mylohyoid ridge).
facial view
Facial view
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Mylohyoid ridge (internal oblique). Located on the lingual surface of the mandible, extending from the
third molar area to the premolar region. Serves as the attachment of the mylohyoid muscle.
lingual view
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facial view
Mandibular (inferior alveolar) canal. Arises at the mandibular foramen on the lingual side of the ramus
and passes downward and forward, moving from the lingual side of the mandible in the third molar
region to the buccal side of the mandible in the premolar region. Contains the inferior alveolar nerve
and vessels.
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lingual view
Submandibular gland fossa. A depression on the lingual side of the mandible below the mylohyoid ridge.
The submandibular gland is located in this region. Due to the thinness of bone, the trabecular pattern of
the bone is very sparse and results in the area being very radiolucent. The fact that it occurs bilaterally
helps to differentiate it from pathology.
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The external oblique ridge (red arrows) and the mylohyoid ridge (blue arrows) usually run parallel with
each other, with the external oblique ridge always being higher on the film.
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The mandibular canal (red arrows identify inferior border of canal) usually runs very close to
the roots of the molars, especially the third molar. This can be a problem when extracting
these teeth. Note the extreme dilaceration (curving) of the roots of the third molar (green
arrow) in the film at left. The film at right shows “kissing” impactions located at the superior
border of the canal.
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BITEWING RADIOGRAPHS

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OCCLUSAL RADIOGRAPHS

DONOVAN TECHNIQUE IN OCCLUSAL
RADIOGRAPHY
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LATERAL RADIOGRAPHIC VIEW OF
MANDIBLE

LATERAL RADIOGRAPHIC VIEW OF
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 This is a accurate radiograph in class III horizontal
impacted third molar.
 It is a good substitute when IOPA cannot be taken.
 It shows the vertical depth of the mandibular bone.
 It shows the bone below the buried tooth ,ectopic teeth
and about any existing pathologies

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ORTHOPANTAMOGRAPH (OPG)

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The angle between the occlusal plane or line parallel to it and the longitudinal axis of the
impacted third molar, in turn, allowed objective classification of the third molars within the Winter
subclasses.

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CONE BEAM COMPUTED TOMOGRAPHY
(CBCT)

CT-scan
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Superior in showing tooth and root
Shape, crown/root relationship,
Tooth inclination and gives exact idea
Of the proximity of IAN and canal to the
Roots.

DIFFICULTY INDICES
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1. PELL & GREGORY DIFFICULTY INDEX
2. WAR LINES
3. PEDERSON’S DIFFICULTY INDEX
4. MODIFIED PARANT’S DIFFICULTY INDEX
5. YAUSA ET.AL. DIFFICULTY INDEX
6. WHARFE’S ASSESSMENT
7. INDEX PREDICTING RISK FOR PERIODONTAL DEFECTS – KUGELBERG 1990
8. DIFFICULTY INDEX BASED ON CLINICAL AND RADIOLOGICAL PARAMETERS

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PELL & GREGORY DIFFICULTY
INDEX

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WINTERS W.A.R. LINES

WAR lines Line extension significance
W-white line Drawn along the occlusal surface of
the erupted mandibular molar and
extends posteriorly over the third
region
Depth of the tooth within the
mandible relationship of
occlusal surface of impacted
tooth within the erupted
molars
A-amber line Drawn from surface of the bone distal
to the third molar to the crest of the
interdental septum between the first
and second molars
The height of the margins of
the alveolar bone enclosing
the tooth
Amount of vertical bone that
requires removal for the
extraction of 3rd molar
R-red line Perpendicular line drawn for the
ambar line to the imaginary point of
application for the elevator
Longer the line more difficult
the extraction
<5 mm-less difficult
For every 1 mm increase
after 5 mm difficulty
increases by 3 times
>5 mm-advised under GA
≥9 mm-very
difficult,denuding of distal of
second molar may mandate
the removal of second molar14-04-2018 95

Another method of judging the depth of the 3rd molar is to divide
the root of the 2nd molar into thirds. A horizontal line is drawn
from the point of application for an elevator to the 2nd molar. If
the point of application is adjacent to the coronal, middle or
apical root third, then the tooth extraction is assessed as easy,
moderate or difficult respectively.

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PEDERSON’S SCALE

DIFFICULTY INDEX : THE INDEX FOR PREDICTING THE DIFFICULTY IN THE REMOVAL OF
MANDIBULAR
THIRD MOLARClassification. Value
Spatial relationship
 Mesioangular 1
 Horizontal/transverse 2
 Vertical 3
 Distoangular 4
Depth
 Level A 1
 Level B 2
 Level C 3
Ramus relationship/space available
 Class I 1
 Class II 2
 Class III 3
Index
7-10(very difficult),5-6(moderately difficult),3-4(minimally difficult)
Pederson Scale(1988)
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MODIFIED PARANT'S DIFFICULTY INDEX
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YAUSA et al DIFFICULTY INDEX

14-04-2018 102Yuasa H, Kawai T, Sugiura M. Classiﬁcation of surgical difﬁculty in extracting impacted third
molars. Br J Oral Maxillofac Surg 2002;40:26–31.

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WHARFE’S ASSESSMENT – MACGREGOR 1985

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INDEX PREDICTING RISK FOR PERIODONTAL
DEFECTS – KUGELBERG 1990

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Variable name Classification Value
Preop plaque index (distal to 2M )
Not visible 0
Visible 1
Preop probing depth (distal to
2M)
≤ 6mm 0
> 6mm 1
Preop intrabony defect ( distal to
2M)
≤ 3mm 0
> 3mm 1
Sagittal inclination of 3rd molar
≤ 50˚ 0
> 50˚ 1

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Contact area 2nd and 3rd molar
Small contact 0
Large contact 1
Resorption distal root of 2nd molar
No 0
Yes 1
Pathologically widened follicle of 3rd
molar
No or Distal 0
Mesial ≥ 2.5 mm 1
Smoking habits
Non-smoker 0
Smoker 1
CONTD…..

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Level of risk indicated by RISK INDEX M3 - Kugelberg
Risk index
M3
Index Score
No risk ≤1
Low risk 2
Moderate risk 3
High risk ≥ 4
Risk index
M3
Predicted
IBD (mm)
0-2 2.0-3.0
3-4 3.5-4.0
≥ 5 >4.0
IBD – intrabony defect

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DIFFICULTY INDEX BASED ON CLINICAL AND
RADIOLOGICAL PARAMETERS

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J. Maxillofac. Oral Surg. DEC 2014

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SURGICAL ANATOMY

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LOCATION:
 Lower 3rd molar is situated at the distal end of the body of
the mandible where it meets a relatively thin ramus.
 Embedded b/w thick buccal alv bone buttressed by
external oblique ridge & the narrow inner cortical plate.
 Ramus offset by 20°
 Retro Molar triangle- depressed roughned area post. to 3rd
molar

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MUSCLES:
Vestibule is formed by the attachment of buccinator
buccally and mylohyoid lingually.
Along the anterior border of the ramus - tendinous
insertion of temporalis Excessive stripping of these
muscle will cause hematoma, pain and trismus.
Lingual pouch – perforation of roots along the lingual
cortical plate.
- may cause # of lingual cortical plate
- displacement of fractured root fragments below the
mylohyoid

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ARTERIES
• Facial artery & facial vein run in close approximation with
lower 2nd molar near the anterior border of masseter.
• Mandibular vessels in retro molar triangle which supply
temporalis tendon.
• Hemorrhage can occur during surgical removal of
impacted tooth if distal incision is not taken laterally
towards cheek.

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INFERIOR ALVEOLAR NERVE
• Lies just below the roots of mandibular molars but
slightly buccally placed in inferior dental canal.
• In case of deep seated impaction special care should be
taken to protect this neurovascular bundle during bone
drilling & tooth sectioning.
• Calcification of inferior alveolar canal is completed
before the roots of 3rd molar are formed. Thus growing
roots may impinge upon the canal or get deflected. So
blind elevation is not advisable.

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ARMAMENTARIUM
FOR THIRD
MOLAR SURGERY

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General Technique
of Third Molar
Removal
Oral Maxillofacial Surg
Clin N Am 19 (2007)
23–43

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The instruments used for surgical removal of impacted teeth are essentially a combination of
instruments used for transalveolar extraction and soft tissue surgery in the mouth. There are only a
few special instruments that are required.
Very often the selection of instruments is a matter of personal preference. It is essential that the
bare minimum instruments are used depending on the case with provision to meet exigencies. This
is because a large collection of unfamiliar instruments and an elaborate tray set-up will cause
embarrassment for both the patient as well the operator and interfere with efficient progress of the
surgery
k. George Varghese, Killey & Kay, Archer, Geoffrey L. Howe

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SURGICAL TECHNIQUE FOR
REMOVAL OF IMPACTED
TOOTH

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PATIENT POSITIONING
• The dental chair is adjusted in such a manner which is comfortable for the patient and at the
same time enables the operator and the assistant to have a clear view of the surgical site.
• Generally, for operative procedures in mandible the occlusal plane of lower teeth should be
parallel to the floor and for the maxillary teeth the occlusal plane of the upper teeth at 45°
angles to the floor

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• The instruments are arranged in a rational order of their intended use (not cluttered) on a sterile
towel placed over the instrument tray of the dental chair or more preferably on a separate
instrument trolley.
• If there is delay in starting the surgery, the instruments should be covered with another towel to
avoid contamination and to maintain the sterility of the instruments.
• The surgeon and the assistant then wear cap and face mask.
• This is followed by scrubbing the hands
• After scrubbing a sterile gown is worn by the surgeon and the assistant.

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Preparation of the surgical site:
• Before preparing the intraoral surgical site it is always desirable to wipe the patient's face with
an antiseptic solution like povidoneiodine (Betadine).
• The third molar area is then swabbed with 0.5% solution of chlorhexidine or betadine.
• Alternatively the patient can be given a mouth wash of the above antiseptic. This is followed
by the administration of local anesthetic injection.

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Draping the patient:
Ideally the head and the front part of the body of the patient should be draped, thus exposing only the
face.
For this the patient's head is covered with a sterile towel, the edge of which is brought under the chin and
fixed with towel clip.
This ensures that the head, neck and shoulders are covered and only the face is exposed.

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Palpation of Anatomical Landmarks
• Before starting the surgical procedure, palpation of the region and locating the anatomical
landmarks is essential.
• The pterygomandibular fold covering the pterygomandibular raphe is usually very prominent
when the mouth is opened wide.
• The external oblique ridge is then located.
• Next, the anterior part of the ramus with the coronoid notch and medially the retromolar fossa
should be identified followed by the medial tendon of temporalis.
• The lingual shelf is palpated.
Locating the anatomical landmarks will give information regarding the underlying bone and will help
the operator as to where the incision is to be given.

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The standard operative plan can be divided into the following stages:
1. Incision to gain access to the area
2. Removal of adequate amount of bone
3. Sectioning and delivery of tooth from the socket
4. Debridement
5. Closure of the incision

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INCISIONS & FLAP DESIGN

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 Incision – 3 parts: Anterior, posterior & intermediate limb
 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)

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The first step in removing the impacted tooth is to reflect a mucoperiosteal flap.
The flap should be
1. Of adequate size to permit access, & exposure of operative site.
2. Allow adequate visibility
3. It should have wide base to assure good blood supply to the soft tissue
4. it should be large enough so that soft tissue surrounding the operative site is not
traumatized during the operation and so that when the flap is replaced, the edges rest on
wide shelf of bone
5. Ensure unhindered healing without periodontal pocket formation distal to second molar
Archer, Killey & Kay, Alling And Alling

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The most important factor in designing the flap is the position of the
third molar which in turn dictates the amount of bone removal required
and the need for tooth sectioning.
More over, due consideration should be given for the lingual nerve,
buccinator muscle and the periodontium distal to second molar while
designing the flap.

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Flap designs
• A small artery, the buccal artery, is sometimes encountered while giving the releasing incision, the injury of
which will lead to mild bleeding.
• The incision should not be continued posteriorly in a straight line, because the mandible diverges laterally.
• If the incision is extended straight, the blade will enter the sublingual space and is likely to damage the
lingual nerve.
• The lateral extension also avoids small vessels emerging from the retromolar fossa.

The base of the flap should be larger than the apex. Essentially, the
releasing incision(s) should be divergent in relation to the site of exposure
so as to not undermine the blood supply of the raised flap.
• The flap should be raised and released in such a manner as to prevent
tearing of the flap. Tearing might lead to a compromised blood supply and
necrosis.
• The ratio between the height of releasing incision(s) and length of base
should not exceed 2:1.
The type of flap used in third molar surgery is classified as full thickness,
which describes an incision that is made from the epithelial
surface to the underlying bone
Basic principles of flap
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• GROOVE’S & MOORE INCISION
• ARCHER’S APPROACH
• ENVELOP FLAP
• L-SHAPED INCISION
• BAYONET SHAPED INCISION
• TRAINGULAR SHAPED INCISION
• LINGUAL BASED TRIANGULAR INCISION
• WARD’S INCISION
• MODIFIED WARD’S INCISION
• NAGESHWAR COMMA SHAPED INCISION
• MODIFIED SZMYD INCISION
• BERWICK’S TONGUE SHAPED FLAP
• BUCCAL EXTENSION FLAP

ENVELOPE
FLAPS
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The most commonly used flap
is the envelope flap, which
extends from just posterior to
the position of the impacted
tooth anteriorly to the level of
the first molar. The posterior
end of the incision is directed
buccally along the external
oblique ridge.
SZYMD FLAP

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Incision is made
horizontally along the
crest of the ridge or in
the buccal gingival
crevice.
Has no vertical
incision.
For shallow or
superficial impactions

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Most common approach.
ADVANTAGES:
1. Generous visibility.
2. Mesial extension possible.
3. The osseous defect can be safely covered .
4. Blood supply up to the margins is adequate.
DISADVANTAGES:
1. The distal component can cut across the insertion of the temporalis tendon.
2. The flap margins lies over the bony defect so formed.
3. Wound dehiscence at the distofacial edge of the preceding second molar is frequent.

Modification of the envelope flap described by Szmyd
(1971).
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1. Free buccal gingival tissue around first and
second molars is spared.
2. Minimal reflected periosteum.
3. Broad-based blood supply to the flap.
4. Adequate exposure and visibility.
5. Good bony support for the soft tissue flap.
6. Closure can be effected with a single suture
and the distal aspect of the third molar
socket.
ADVANTAGES OF MODIFIED FLAP

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TRIANGULAR FLAP
A small ‘V’ shaped incision, made with one point at
distobuccal line angle of the second molar.
One vertical limb followed the external oblique ridge, and
the other avoided the gingival sulcus and extended down
to the mucogingival junction, doen’t involve papilla of
mandibular 2nd molar.

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ARCHER’S APPROACH

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Standard incision(Ward’s incision,1968)

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PARTS OF INCISION

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Limb C - 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)
• In case of unerupted tooth ,intermediate incision is not needed.The limb A is extended upto the
middle of the distal surface of the 2nd molar

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• This incision is started from a point approximately 6.4 mm (14 in)down in the buccal sulcus appox at the junction of
posterior and middle thirds of second molar; the line passes upwards to distobucaal angle of second molar at gingival
margin.
• The incision now passes cervically behind the tooth to middle of its posterior surface if third molar is unerupted.
• It is then extended posteriorly and laterally along the anterior border of the ramus for a maximum of 25.4 mm
• Extension of the incision further posteriorly may result in prolapse of buccal pad of fat or lead to marked trismus and
swelling postoperatively.

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MODIFIED Ward’s incision
Anterior incision is commenced at
the distobuccal corner of the crown of
mandibular 1st molar instead of 2nd molar

BAYONET FLAPS
• Similar to the molar sulcus incision
• The incision is similar to the second molar sulcus incision with the
addition of an oblique vestibular extension in the sulcus area
which is angled forward.
• However, oblique vestibular extension is made in the sulcus
region .
• This extension should be angled forward to facilitate suturing and
to optimize blood supply to the anterior part of the flap.
• This type of incision gives excellent buccal visibility. A variant of
this incision is to limit the sulcus incision buccal to the second
molar only to the distobuccal part of the gingiva .
• This flap offers limited visibility and should only be used for
superficially and buccally placed third molars. 14-04-2018 145

‘L’ SHAPED FLAP• L flap is similar to the bayonet flap only difference being that the incision is
made a couple of millimeters away from the marginal gingiva. It optimizes
marginal attachment healing next to the second molar.
• Vertical relieving incision is given at 45˚ angle to the long axis of the 2nd
molar and runs straight anteriorly and downwards.
• This procedure optimizes marginal attachment healing next to the second
molar but requires that the main surgical approach to the third molar is at a
distance from the second molar.
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LINGUAL FLAP
• This flap is used with a lingual approach for third molar removal.
• The incision starts on the ascending ramus aiming at the distobuccal corner of the
second molar, follows the distal surface of the second molar as a sulcular incision, and
then continues lingually to the first molar region.
• A sulcular incision is also made along the buccal aspect of the second molar
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BUCCAL EXTENSION
FLAP

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VESTIBULAR TONGUE SHAPED FLAP
BY BERWICK’S
(1966)

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• Extended onto the buccal shelf of the mandible
• Incision line did not lie over the bony defect created by
the removal of the impacted teeth
• Its base at the distolingual aspect of the second molar

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GROOVE & MOORE
• In the year 1970 they designed three flaps
• Produced an apparent decrease in pocketing distal
to 2nd molar
• A collar of tissue was preserved around the 2nd
molar hence decreasing pocket formation
• A lingual extension of the incision allowed for
exposure of the lingual aspect as well

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NAGESHWAR’S COMMA SHAPED
INCISION (2002)

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• Begins at a point distal to the second molar, smoothly curved up
to meet the gingival crest at the distobuccal line angle of the
second molar.
• The incision is continued as a crevicular incision around the
distal aspect of the second molar.
• Allows reflection of a distolingually based flap adequately exposing the entire third molar area.
• The incision and flap design seems best suited to cases in which the third molar is completely covered
with soft tissues.
• In cases in which part of the impacted tooth is visible in the mouth, a small modification is made.

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Advantages
• No part of wound lies on resultant bone defect
• Less postoperative pain and swelling

FLAP ELEVATION
Distolingual spur
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• The sharp end of the periosteal elevator is inserted in the region of vertical incision to ensure that the
incision has reached up to bone.
• If not, the sharp tip of the instrument is employed to sever the remaining attachment.
• The blunt end of the instrument is then passed beneath the mucoperiosteum to reflect the soft tissue in
the correct plane.
• Care should be taken not to strip the periosteum from the mucosa while reflecting.

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• The mucoperiosteal flap is then reflected
laterally to the external oblique ridge with a
periosteal elevator and held in this position
with an retractor (third molar retractor).
• The flap reflection should be limited to
external oblique ridge laterally, because
reflecting beyond this area leads to
increased dead space resulting in more
edema postoperatively.

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• The next major step is to remove the bone around the impacted
tooth.
• The amount of bone removal varies with the depth of impaction.
• This can be accomplished either by use of bur, or chisel and mallet or
a combination of the two methods.
• Whatever may the method used (which may be of individual
preference), the aim is to remove sufficient amount of bone to free the
tooth from obstruction and to provide a point of application for the
elevator.

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• If adequate amount of bone covering the tooth has been removed, an attempt can be made to elevate
the tooth from the socket.
• Application of a great amount of force without adequate bone removal can result either in fracture of
the tooth or fracture of the mandible.
• Due to the above risk dental extraction forceps and elevators with great mechanical efficiency like
cross bar elevators are contraindicated for the removal of impacted third molar.

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• Once the obstructing bone has been removed, only a slight amount of force alone is needed to
deliver the tooth.
• Elevators with less mechanical efficiency like Warwick James elevator (straight and curved type)
and Coupland chisels are recommended for this purpose.
• The # 301, Crane pick and Cogswell B elevators also serve this function well.

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• It is a common practice to use a broad elevator between the buccal surface of the impacted tooth
and the external oblique ridge in order to elevate a tooth or root fragment.
• This technique places the external oblique ridge, one of the buttresses of the mandible and the
lingual plate at risk of fracture.
• If such a fracture is unrecognized, a substantial late presenting sequestrum or immediate lingual
nerve injury is possible (Farish and Bouloux, 2007).

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• At the time of elevating the tooth, the index finger of the operator's left hand should rest on the
occlusal surface of the wisdom tooth to judge its movement and the other fingers support the
mandible.
• Because the impacted tooth has never sustained occlusal force, their periodontal ligament space is
wider and less tenacious and they can be easily displaced if adequate bone is removed and
elevation forces are applied in a proper direction.

DIFFERENCES BETWEEN BUR & CHISEL
TECHNIQUE
Sl.No Criteria. Chisel&Mallet Bur
1. Technique Difficult Easy.
2. Controll over bone cutting Uncntrolled&chances
of fracture is more.
Controlled.
3. Patient acceptance. Not tolerated in L.A. Well tolerated in L.A.
4. Healing of bone. Good Delayed Healing
5. Postoperative edema Less More.
6. Dry socket. Less. More.
7. Postoperative Infection. Less. More.
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BONE REMOVAL WITH BUR (MOORE & GILBE COLLAR
TECHNIQUE)
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• No. 7 or 8 round bur can be used in the range of 5000-10,000 rpm.
• Use of bur should always be done with copious saline irrigation to prevent thermal injury.
• Bone should be removed from the occlusal surface of the tooth.
• A channel is formed in the bone lateral and posterior to the impacted third molar to the cervical
level of the crown contour.
• Adequate amount of trough should be created to remove any bony obstruction for exposure and
delivery of the tooth.
• Careful bone removal should be done around the distal and distolingual aspect of the tooth without
damaging the lingual nerve which lies in the vicinity of the lingual plate adjacent to the third molar

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• Conventional tech of using bur.
• Rosehead round bur no.3 is used to create a gutter along the buccal side & distal aspect of
tooth.
• A point of elevation is created with bur.
• Amount of bone sacrificed is less.
• Can be used in old patient.
• Convenient for patient.

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LATERAL TREPHINATION TECHNIQUE
(BOWDLER HENRY; 1969)
• Indicated for removal of unerupted third molars
in the age group of 9 to 18 years.
• A extented S shaped incision is made from the
retro molar fossa across external oblique ridge.
• Such an incision leaves behind 5mm cuff of
attached mucosa at the
distobuccal region of second molar.

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• A round toller bone bur is used to trephine the crypts of
third molar. After anterior posterior length of crypt has
been determined, a vertical cut is made through
external plate
• A second cut is made through the outer plate at the
posterior end of crypt at an angle of 45̊ from the row of
trephine bur.
• A chisel is applied in vertical direction to out fracture
outerplate

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Complications:-
∙ A transient anaesthesia in post-operative period
∙ Buccal vessel may be cut during the incision.
∙ Damage to 2nd molar roots
∙ Fracture of mandible during bone cutting
∙ Bleeding
Advantages
∙ Bone healing is excellent without any loss of alveolar bone around 2nd molar.
∙ Local anaesthesia preferred over general anaesthesia

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SPLIT BONE / LINGUAL SPLIT TECHNIQUE /
SIR WILLIAM KELSEY FRY(1933)
• Described by Sir William Kelsey Fry (1933).
• Later popularized by Terence G ward(1956)
• Specially for lingually placed tooth.
• Modified by Dr. Davis in 1960 & Lewis in 1980

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• The technique involves the use of a chisel and mallet to remove or displace the lingual plate
of bone adjacent to lower third molar teeth.
• A small amount of buccal bone is often removed to facilitate exposure of the crown and provide
a point of application for a dental elevator.
• Although tooth division is usually not required, it usually can be achieved with the chisel.
• Although the lingual split technique is well suited to patients receiving sedation or general
anesthesia, it is generally not well suited to surgery conducted purely under local anesthesia.

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ARMAMENTARIUM -

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• An incision is made from the retromolar area to the mesial aspect of the first molar or the distal
aspect of the second molar, depending on whether an envelope incision or a triangular flap is
used. The latter approach involves a vertical buccal relieving incision on the distal aspect of the
second molar and is preferred by the author (GFB) because it allows better retraction and
improved visibility.
• The buccal flap is raised in a subperiosteal plane using a #9 periosteal elevator.
• The flap should be extended just slightly beyond the external oblique ridge to prevent
excessive dead space beneath the flap.
• A 2-0 silk retraction suture is placed through the apex of the triangular flap.
• The suture should be clamped with a heavy hemostat 6 to 8 inches from the flap, which is then
allowed to rest on skin of the cheek, where it serves to keep the flap retracted.

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• The flap should be raised along a broad length before proceeding deeper.
• This latter approach reduces the tension placed on the lingual nerve, which adheres to the
periosteum.
• The flap should extend from the mesial of the second molar to the lingual aspect of the anterior
ramus.
• The inferior aspect of the pterygomandibular raphe and superior constrictor muscle together
with a small portion of the mylohyoid muscle are included in this flap.
• The lingual nerve enters the sublingual space by passing between the superior constrictor and
mylohyoid muscles; at this location the nerve is immediately beneath the periosteum and at
risk from trauma.

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• After lingual flap elevation, a left or right Hovell’s retractor (depending on
which side of
the mandible is being operated) is placed beneath the flap and allowed to sit
passively.
• The buccal flap, previously secured with the silk suture, is retracted in part
from the weight of the heavy hemostat.
• The first finger and thumb grasp the 3-mm chisel while the second or third
finger is placed on the first molar or alveolus to stabilize the instrument.
• The blade of the chisel is kept vertical, with the bevel facing posteriorly, and
a vertical cut is made at the mesial aspect of the third molar.

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A 5-mm chisel is then used to create a horizontal
cut from the inferior aspect of the previously
made vertical cut to the distobuccal aspect of
the third molar

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The bevel should be kept facing superiorly for this
osteotomy cut.
The superior aspect of the buccal cortex adjacent
to the third molar is delivered and exposes a portion
of the third molar crown and provides a mesial
or buccal point of elevation/access

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After completion of the buccal osteotomies, the
crown of the impacted tooth is completely visible, with
good access for application of elevators.

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The most difficult and crucial aspect of
the lingual split follows. The 5-mm chisel is then
positioned with the edge of the blade located
just posterior to the distolingual aspect of the
crown of the third molar. The chisel edge should
lie just lateral to the lingual cortex, and the cutting
edge should be kept parallel to the sagittal plane

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The handle of the chisel should be approximately
45to the horizontal.
Positioning the chisel meticulously helps ensure that
when the chisel is struck with the mallet, the cutting
edge penetrates the superior aspect of the alveolus
just inside the lingual cortex and results in
displacement of the cortex lingually.

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• The anterior aspect of the fractured lingual cortex
usually extends as far as the mesial of the third molar,
whereas the posterior aspect may extend up to 1 cm
distally.
• The posterior extent of the fracture is
limited by the natural bony lingual concavity
behind the third molar.
• When the chisel blade is originally positioned for the
osteotomy, the cutting edge can be rotated from
parallel to the sagittal plane to shorten the posterior
extent of the fracture.
• The inferior extent of the fracture typically involves the
mylohyoid ridge

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(A) With vertical mandibular impactions (Pell and Gregory classes B and C) it is necessary to
remove bone overlying
the occlusal surface of the tooth. This procedure may be completed before or after removal of
the buccal cortex.
(B) The thin overlying bone has been removed with a chisel after the buccal osteotomy was
completed, which often can be completed without the mallet using hand pressure alone.

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(A) With mesioangular mandibular impactions
a variable amount of overlying bone must be removed.
(B) The overlying bone has been removed with a chisel
after the buccal osteotomy has been completed. Note
that the inferior extent of the buccal osteotomy does
not have to extend to the inferior extent of the tooth
but only as far as is needed to obtain a buccal point of
application for luxation before displacing the tooth
lingually.

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(A) With horizontal impactions a significant
amount of overlying bone may need to be removed.
This approach occasionally may necessitate the use of
a bur.
(B) Adequate removal of buccal and occlusal
bone provides a point of elevation and exposes the
distolingual aspect of the tooth.

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Coupland #1 or straight Warwick James used
to engage mesial aspect and provide initial mobility.
Occlusal view illustrates use of a Coupland elevator
buccally to displace the tooth lingually.

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Occlusal view illustrates displacement of the
tooth lingually for easy retrieval.

INCISION VERTICAL STOP CUT
HORIZONTAL CUT SPLIT OF DISTOLINGUAL BONE
REMOVAL OF PENINSULA BETWEEN
BUCCAL & DISTOLINGUAL BONE ELEVATION
REMOVAL OF DISTOLINGUAL
BONE CLOSURE
Split Bone / Lingual Split Technique
Sir William Kelsey Fry(1933)

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ADVANTAGES
• Faster tooth removal.
• Less risk of inferior alveolar nerve damage.
• Reduces the size of residual blood clot by means of saucerization of the socket .
• Decreased risk of damage to the periodontium of the second molar.
• Decreased risk of socket healing problems.

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DRAWBACKS
• Risk of damage to the lingual nerve. The incidence of lingual nerve and inferior alveolar
nerve damage has been reported as 1-6.6% .
• Increased risk of postoperative infection
• Patient discomfort due to the use of a chisel and mallet for lingual bone removal or fracturing.
• Only suitable for young patients with elastic bone

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• Davis's technique mentions not to separate the mucoperiosteom from lingual area of bone. The
bone was released in segments to allow tactile control of osteotome to prevent penetration of the
osteotome into soft tissue. More than one osteotome per impaction was usually used to ensure sharp
cutting edge. Wedging the osteotome between tooth and bone should be avoided to prevent fracture
of the mandible.
• Lewis technique: Lewis (1980) modified the lingual split-bone technique by minimizing periosteal
reflection and buccal bone removal and by preserving the fractured lingual plate. He claims that
these modifications reduce the possibility of lingual nerve damage, minimize periodontal pocket
formation, and improve the chances for primary wound healings.
Modified distolingual bone splitting technique

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TOOTH SECTIONING

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• Rationale of tooth sectioning is to create a space into which impacted tooth can be displaced &
thence removed.
Indication:
• Multi-rooted teeth with different lines of withdrawal
• Tooth division may be done using a bur, an osteotome or tooth-splitting forceps (tooth shear
forceps).
Tooth Sectioning
Bone belongs to the patient
and the tooth belongs to the
surgeon

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Mesioangular mandibular impaction removal.
(A) Buccal and distal trough created and tooth elevated
distally with a #301 elevator or a purchase point and a
Cogswell B elevator.
(B) Distal portion of crown sectioned and removed
followed by elevation of the mesial crown segment and roots.
(C) Sectioning the roots with elevation of the distal segment
followed by elevation of the mesial segment.

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Horizontal mandibular
impaction removal.
(A) The crown is sectioned from root and
removed as a unit or may
need to be sectioned longitudinally for
removal.
(B) Elevation of roots with a purchase point
and a Cogswell B elevator.
Roots may need to be sectioned into two
pieces and removed separately, with upper
followed by lower.

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Vertical mandibular
impaction removal.
(A) Buccal and distal trough created and
purchase point placed and
elevation with a #301 elevator or a
Cogswell B elevator.
(B) Distal crown segment sectioned and
removed followed by a purchase point in
the roots for elevation with a Cogswell B or
a #301 elevator.
C) Tooth and root units split
and removed distal followed by mesial with
purchase points for Cogswell B and #301
elevators as required.
(D) Crown removed horizontally and roots
split for removal distal followed by mesial
with purchase points for Cogswell B and
#301 elevators as required.

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Distoangular mandibular
impaction removal.
(A) Buccal and distal trough created and
distal portion of crown sectioned
followed by a purchase point in the
mesial of the remaining tooth structure
followed by elevation.
(B) Crown sectioned horizontally and
removed followed by sectioning of the
remaining roots and elevation of each
root independently.

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(A) Elevation of a remaining root fragment with a Cryer- or Winter-type elevator in a distal
direction removes intraseptal bone but forces the root against the intact distal socket wall, where
it resists removal.
(B) A well-placed purchase point in the distal of the root fragment allows a Cogswell B or
Heidbrink elevator to guide the root mesially, where it meets no resistance to removal.

Luxation of the mesial segment of an impacted tooth using a straight elevator.
a Diagrammatic illustration. b Clinical photograph
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Segments of tooth after
removal
Empty socket after extraction of tooth
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a Removal of follicle using a hemostat and periapical curette.
b Surgical field after placement of sutures
14-04-2018 201

a Radiograph showing impacted mandibular third molar (partial bone impaction) with
a distoangular position.
b Clinical photograph of the area of impaction
14-04-2018 202

The horizontal incision extends as far as the mesial aspect of the first molar.
14-04-2018 203

Diagrammatic illustration (a) and clinical photograph (b)
showing the horizontal incision upon completion
14-04-2018 204

Reflection of the mucoperiosteal flap, and partial exposure of the crown of the
impacted tooth.
a Diagrammatic illustration. b Clinical photograph 14-04-2018 205

Removal of bone on the buccal and distal aspects of the crown of the tooth. The
groove is created to facilitate luxation.

Sectioning of the distal portion of the crown of the impacted tooth using a fissure bur.
14-04-2018 207

Removal of the distal part of the crown using a straight elevator.
14-04-2018 208

Luxation of the impacted tooth in the distal direction, after creating a pathway for
removal.

Tooth after removal Surgical field after suturing
14-04-2018 210

a Radiograph showing impacted mandibular thirdmolar in the horizontal position.
b Clinical photograph of the area of the impacted tooth.
14-04-2018 212

Horizontal incision using a scalpelwith a no. 15 blade.
14-04-2018 213

Reflection of flap and retraction with the broad end of a periosteal elevator.
a Diagrammatic illustration b Clinical photograph
14-04-2018 214

Removal of bone using a round bur, to expose the crown of the impacted tooth.
14-04-2018 215

Sectioning of tooth at the cervical line using a fissure bur.
The diagrammatic illustration (a) shows the position
beyond which the bur must not proceed, to avoid injury of the inferior alveolar nerve
14-04-2018 216

Separation of crown from the root, with rotation of the elevator in a groove created
on the impacted tooth
14-04-2018 217

Diagrammatic illustration (a) and clinical photograph (b)
showing removal of the crown of the tooth using a straight elevator
14-04-2018 218

Luxation of the root of using an elevator.
14-04-2018 219

a Operation site after removal of tooth. b Surgical field after
suturing 14-04-2018 220

BUCCAL
CORTICOTOMY
• Used in deeply impacted mandibular teeth.
• in this tech a trapezoidal flap is raised in mandibular
molar regions, and rectangular window is made over
deeply to impacted tooth using a narrow fissure bur, with
the mesial and distal cuts almost reaching the inferior
border of mandible.
• the buccal cortictomy window is removed. Deeply molar
is exposed, divided a bur and removed the molar.
• Bony fragments removed at buccal corticotomy is
replaced and secured with wires or plates and screw at
mesial and distal edges, and wound is sutured.
14-04-2018 222

14-04-2018 223
DEBRIDEMENT & CLOSURE

14-04-2018 224
• Once the impacted tooth is delivered from the alveolar process the surgeon must pay strict
attention to debriding the wound of all particular bone chips and other debris.
• This is best accomplished by mechanically debriding the socket and the area under the flap with
a periapical curette.
• A bone file is used to smooth any rough and sharp edges of the bone. Instead an acrylic trimmer
on a handpiece also can be used.
DEBRIDEMENT

14-04-2018 225
• A mosquito hemostat is employed to remove any remnant of the dental follicle in order to
prevent the formation of a cyst later on.
• Fractured interdental septum or large pieces of bone is also removed using a hemostat.
• In certain instances a fractured portion of lingual plate may remain. Using a hemostat it is
palpated to determine whether it is mobile. If it is having adequate attachment it may be left as
such.

14-04-2018 226
• If the vitality of the fractured piece is doubtful it may be detached gently from the periosteum
without causing injury to lingual nerve which may be lying nearby.
• Finally the socket and the wound margins (including under surface of mucoperiosteum) is
irrigated with saline to remove bone and tooth debris.
• It has been observed that, the more irrigation is used, the less likely the patient is to develop a
dry socket, delayed healing, or other complications.

14-04-2018 227
Wound Closure
• Bleeding from the socket is completely arrested before attempting
closure.
• Troublesome bleeding from the socket can be controlled using bone
wax, surgicel or gelfoam.
• The flap is then returned to its original position and the initial suture
placed just distal to the second molar.
• It is opined that this suture reduces the possibility of the development
of periodontal pocket distal to the second molar.

14-04-2018 228
• In cases where the anterior vertical incision has been carried forwards up to the mesial aspect of
second molar, the wound is closed with two sutures.
• Here the first suture is placed between the first and second molar by passing the needle from
lingual to buccal side through the interdental space between the two.
• After this the second suture is placed in the usual position distal to second molar.

14-04-2018 229
• If the flap is not repositioned properly and sutured correctly it may be heaped up over the crown of
the second molar.
• This will lead to its ulceration due to impingement of the upper teeth during closure of the mouth
and final breakdown of the wound.
• The patient is then asked to bite firmly on a gauze piece for 30 mts. to one hour or till the bleeding
stops.
• Following the procedure oral and written postoperative instructions can greatly help the patient
and also ensure better patient compliance.

14-04-2018 231
POST – OPERATIVE CARE

14-04-2018 232
The patient and the by stander should be informed that unnecessary pain and complications like
infection, bleeding and swelling can be minimized if the instructions are followed carefully.

14-04-2018 233
Immediately Following Surgery
• Bite on the gauze pad placed over the surgical site for an hour. After
this time, the gauze pad should be removed and discarded. It may be
replaced by another gauze pad if there is bleeding.
• Avoid vigorous mouth rinsing or touching the wound area following
surgery. This may initiate bleeding by dislodging the blood clot that has
formed.
• To minimize swelling, place ice packs to the side of the face where
surgery was performed.

14-04-2018 234
• Take the prescribed pain medications as soon as
possible so that it is digested before the local anesthetic
effect has worn off. Avoid taking medications in empty
stomach to avoid nausea and gastritis.
• Restrict activities on the day of surgery and resume
normal activity when one is comfortable. Excessive
physical activity may initiate bleeding.
• Do not smoke under any circumstances.

14-04-2018 235
Bleeding
• A certain amount of bleeding is to be expected following surgery.
• Slight bleeding or oozing causing redness in the saliva is very common. For this reason, the gauze will
always appear red when it is removed.
• Excessive bleeding may be controlled by first gently rinsing with ice cold water or wiping any old clots
from the mouth and then placing a gauze pad over the area and biting firmly for sixty minutes. Repeat
as necessary.

14-04-2018 236
• If bleeding continues, bite on a moistened tea bag for thirty minutes. The tannic acid in the tea bag
helps to form a clot by contracting the bleeding vessels. This can be repeated several times.
• To minimize further bleeding, sit upright, maintain constant pressure on the gauze (no talking or
chewing) and avoid exercise.
• If bleeding does not subside after 6-8 hours, inform the doctor.

14-04-2018 237
Swelling
• The swelling that is normally expected is usually proportional to the surgery involved.
• Simple tooth extraction generally do not produce much swelling.
• However, if there was a fair amount of cheek retraction and bone removal involved with the
surgical procedure, mild to moderate swelling can be expected on the affected side.

14-04-2018 238
• The swelling will not become apparent until the evening or the day following surgery. It will reach its
maximum on the second or the third day postoperatively.
• The swelling may be minimized by the immediate application of ice bag following the procedure to the
side of the face where surgery was performed. If ice bag is not available sealed plastic bag filled with
crushed ice may be used.
• The ice bag should be applied for 20 minutes on and five minutes off for the afternoon and evening
following the surgery. After 24 hours, ice has no beneficial effect.
• Warm mouth washes and vigorous swishing should be avoided for 12 to 24 hours following surgery
since it may interfere with formation of blood clot. This eventually results in postsurgical bleeding.

14-04-2018 239
Once, the initial oozing of blood has stopped (i.e. after 12 to 24 hours) warm saline mouth
washes (half teaspoon salt in a glass of water) may be used fourth hourly. The mouth should be
filled with normal saline as hot as the patient can tolerate and the head is held to one side in such
a way the fluid lies over the area of surgery. When the fluid cools it should be expectorated and
the process repeated. Regular use of mouth wash markedly relieves the pain and edema.

14-04-2018 240
Pain
• Postoperative pain is only mild or moderate and is
controlled easily by the use of mild analgesics like
aspirin, paracetamol, ibuprofen or combinations of
aspirin, phenacetin and codeine.
• Pain or discomfort following surgery is expected to last 4 to 5 days. For many patients, on the third and
fourth day require more pain medicine than on the first and second days. Following the fourth day pain
should subside more and more everyday.
• If the pain is very severe it indicates the possibility of something going wrong and the most likely cause
is the development of infection. In such an instance the doctor should be contacted.

14-04-2018 241
Antibiotics
• Antibiotics are not given as a routine procedure after oral surgery. The over use of antibiotics leading
to the development of resistant bacteria is well documented.
So careful consideration is given to each circumstance when deciding whether antibiotics are
necessary.
In specific circumstances, antibiotics will be given to help prevent infection or treat an existing infection.

14-04-2018 242
Diet
• Drink plenty of fluids. Try to drink 5 to 6 glasses on the first day.
• Drink from a glass or a cup and do not use a straw. The sucking motion will suck out the healing
blood clot and start the bleeding again.
• Avoid hot liquids or food till the anesthesia effect wears off. Otherwise, it can result in
burning/scalding of lips and tongue.
• Soft food and liquids can be eaten on the day of surgery. The act of chewing does not damage
anything, but should avoid chewing sharp or hard objects at the surgical site for a week.
• Return to a normal diet as soon as possible unless otherwise directed. Eating multiple small
meals is easier than three regular meals for the first few days.

14-04-2018 243
Oral Hygiene
• Good oral hygiene is essential to proper healing of any oral surgery site.
• Brushing of teeth can be resumed from the night of surgery onwards. Avoid disturbing the surgical
site so as not to loosen or remove the blood clot.
• Mouthwashes have an alcohol base and it may irritate fresh oral wounds. After a few days, dilute
the mouthwash with water and rinse the mouth.

14-04-2018 244
Stiffness of Jaw (Trismus)
• Perform active jaw opening from the next day of surgery to prevent development of jaw
stiffness. This will not cause tearing of the suture.
• If the muscles of the jaw become stiff, chewing gum at intervals will help to relax the muscles.
Use of warm, moist heat to the outside of the face over these muscles also will help to relieve
this.

14-04-2018 245
Activity
• Keep physical activities to a minimum for 6-12 hours following surgery.
Suture Removal
• Sutures should be left in place for about seven days.

14-04-2018 246
Summary of Instructions to Patient Following Surgical Removal of Impacted
Tooth
1. Remove the gauze pack after 30 mts to one hour.
2. Apply ice (ice cubes taken in a polythene bag) on the face for the first 24 hours.
3. For the first day take cold liquids or semisolids.
4. Avoid warm saline gargle in the first 24 hours.
5. There may be mild to moderate swelling on the side of the face for three to four days.

14-04-2018 247
6. Mild bleeding/oozing of blood can be there from the surgical site for one to two days. In the event
of excessive bleeding bite on a fresh piece of sterile gauze and inform the doctor.
7. In the first few days difficulty may be experienced in opening the mouth. To avoid this, from the
next day of surgery onwards try to open the mouth
forcefully.

14-04-2018 248
8. From the next day onwards after surgery or once the oozing of blood has completely stopped, warm
saline mouth-baths can be used at fourth hourly
intervals. Avoid application of dry heat on the face.
9. Tooth brushing have to be done from the next day on wards.
10. Take the drugs prescribed by the doctor at regular intervals.
11. Avoid alcohol, smoking, physical exercise and long journey for the next few days.
12. Report for review to the doctor as suggested for suture removal.

14-04-2018 250
INTRA – OPERATIVE COMPLICATIONS

 During incision
• Bleeding from retromolar vessels
• Bleeding from facial vessels
• Damage to lingual nerve
14-04-2018 251

DURING BONE REMOVAL
USE OF BURS
• Accidental burns
• Injury to IAC
• Injury to adjacent tooth
• Injury to lingual nerve
• Laceration of soft tissue
• Necrosis of bone
• Emphysema
USE OF CHISEL
• Splintering of bone
• Fracture of mandible
• Displacement of tooth into
lingual pouch
• Injury to lingual nerve
• Injury to adjacent tooth
• Soft tissue injury
252

COMPLICATION DURING SECTIONING OF
TOOTH
USING BUR
• Incorrect line of
sectioning of tooth
• Injury to mandibular
canal
• Breakage of bur
USING OSTEOTOME
253

14-04-2018 254
• Fracture of root/tooth
• Luxation of neighboring tooth/ fractured restoration
• Soft tissue injury due to slipping of elevator
• Injury to inferior alveolar neurovascular bundle
• Forcing tooth root into submandibular space or inferior alveolar nerve canal
• Breakage of instruments
• TMJ Dislocation – careful history
DURING ELEVATION OR TOOTH REMOVAL

14-04-2018 255
POST – OPERATIVE COMPLICATIONS

14-04-2018 256
Post-operative Complications
• IMMEDIATE
- Hemorrhage
- Pain
- Edema
- Trismus
• DELAYED
- Alveolitis
- Infection
- Trismus
- Nerve injury
a. IAN
b. LINGUAL NERVE

14-04-2018 258
TOPICAL HAEMOSTATIC AGENTS
• MECHANICAL AGENTS-
1. bone wax (non-resorbable)
• CHEMICAL AGENTS- styptics
1. Vasoconstrictor- epinephrine
2. Ferric sulphate
• BIOLOGIC AGENTS
1. Thrombin
• ABSORBABLE MECHANICAL HAEMOSTATIC AGENTS
Intrinsic action agents
1. Gelatin- gelfoam; spongostan
2. Absorbable collagen- collatape; actifoam
3. Microfibillar collagen hemostats- avitene
Extrinsic action agents
surgicel

• SWELLING
This is an expected squeal of 3rd molar surgery.
Patients with round puffy face frequently develop more swelling.
Parenteral administration of corticosteroids is found to be extremely useful to minimize postoperative edema.
The role of ice pack applied intermittently for first 24 hours.
14-04-2018 259

TRISMU
S
 Is defined as prolonged, tetanic spasm of the jaw muscles by which the normal opening of the mouth is
restricted.
Problem
 Acute phase –
 Pain is produced by haemorrhage
 Chronic phase –
 Hypomobility is due to organization of haematoma with subsequent fibrosis and
scaring
14-04-2018 260

 Management
 Heat therapy – 20 min every hour
 Warm saline rinse
 Analgesic
 Muscle relaxant
 Physiotherapy
 If Condition does not improve in 48 – 72 hr
 suspect infection
 Antibiotics
14-04-2018 261

14-04-2018 263
DRY SOCKET
DEFINITION
“postoperative pain in and around the extraction site, which increases in severity
at any time between 1 and 3 days after the extraction accompanied by a partially or
totally disintegrated blood clot within the alveolar socket with or without halitosis.”
First described by CRAWFORD in 1876
SYNONYMS
➢alveolar osteitis(AO)
➢alveolitis
➢localized osteitis
➢ alveolitis sicca dolorosa
➢localized alveolar osteitis
➢fibrinolytic alveolitis
➢septic socket
➢necrotic socket
➢alveolalgia

14-04-2018 264
ONSET AND DURATION
• Mostly 1-3 days after extraction
• Unlikely –before first operative day
Because the blood contains anti-plasmin that must be consumed before clot
disintegration can take place.
• The duration of AO varies depending on the severity of disease ,but it usually ranges from 5-10
days
• The incidence of alveolitis was 2.7 times greater among females than among males

14-04-2018 265
SIGNS AND SYMPTOMS
• The denuded alveolar bone is painful and tender
• Some patients may also complain of intense
continuous pain radiating to the ipsilateral ear, temporal
region or the eye
• Regional lymphadenopathy(occasionally)
• Unpleasant taste(occasionally) but foul order
▪ Trismus
▪ Confirmation by probing

14-04-2018 266
• Alveolar osteitis is a condition in which the blood clot
disintegrates. At first the clot has a dirty grey
appearance, and then it falls out leaving a bony socket
bare of granulation tissue.
• Suppuration is absent, but a foul odour is present, and
severe neuralgic pain persists for days. The condition
is also known as “dry socket.”
• The symptoms generally set in on the second or third
day after the extraction of the tooth, and last from 10 to
40 days
Thoma

14-04-2018 267
The diagnosis is confirmed by passing a small curette into the extraction
wound; in dry socket, bare bone is encountered which is extremely
sensitive.
The socket is not always open; it may contain necrotic granulation tissue
not as yet expelled, or the orifice may be covered by a flap of tissue so
that detection is difficult.
On account of the extreme radiating pain of prolonged duration, this
complication is without doubt one of the most distressing postoperative
sequelae to extraction. It occurs in spite of the most careful aseptic proce-
dure, and regardless of the ability and judgment of the surgeon
Thoma

14-04-2018 268
Theories of aetiology
• Catellani (1989)
Stated that the pyrogens secreted by the bacteria are in
direct activators of the fibrinolysis in vivo.
• Simpson (1969)
Demonstrated through microscopic studies on the monkey
that the fragments are commonly observed in any
extraction and do not necessarily cause problems
although they might cause inflammation and some delay
in chronology of alveolar repair.

14-04-2018 269
• Nitizans(1978)
Demonstrated a possible relationship between the presence of aerobic microorganism and aetiology of
dry socket.
They also reported high Fibrinolytic activity in the cultures of anaerobic Treponema Denticola found in
the periodontal disease.
• Mitchell (1986)
Identified periodontal pathogen bacteria that produce enzymes with Fibrinolytic activity such as
porphyromonas gingivalis, fusobacterium nucleatum.
• Hedstrom and Sjogren (2007)
Concluded that local treatment with tetracyclines and chlorhexidine 0.12% mouthwash (Preoperatively
and postoperatively 7 days) was clinically significant in preventing dry socket in mandibular 3rd molar
extraction.

14-04-2018 270
• Tjernberg 1979-Existing infection around apex of the
tooth
• Lehner 1958- effect of epinephrine- dec bleeding
• Traumatic extraction
• Excessive irrigation or curettage of the alveolous after
extraction
• Physical dislodgement of the clot
• Local blood perfusion and anaesthesia
• Oral contraceptives-estrogens, like pyrogens, will
activate the fibrinolytic system indirectly

14-04-2018 271
∙ Birn theory (1973)
Suggested that trauma and infection cause inflammation of bone marrow with the resultant
release of tissue activators that convert the plasminogen in clot to plasmin. The Fibrinolytic
agent then dissolves the blood clot and at same time release kinins or kinogens, which is
also in the clot dissolution, leading to severe pain.
Birn considered that the trauma resulting from extraction as well as aggressive curettage
might harm the alveolar cells causing inflammation of the alveolar osseous medulla and
release of all mediators to the alveolus where they cause fibrinolysis activity increasing the
risk of dry socket.

14-04-2018 272
PATHOGENESIS
BIRN FIBRINOLYTIC THEORY

14-04-2018 274
RISK FACTORS
• Previous experience of AO
• Deeply impacted mandibular third
molar (risk factor is directly
proportional to increasing severity of impaction)
• Poor oral hygiene of patient
• Active or recent history of acute ulcerative gingivitis or
pericoronitis associated with the tooth to be extracted
• Smoking (especially >20 cigarettes per day)
• Use of oral contraceptives
• Immunocompromised individuals

14-04-2018 275
MANAGEMENT
• The degenerated and lost blood clot in the tooth socket must be replaced.
• With the loss of the protective blanket of a healthy, organizing blood clot, the denuded bony
socket walls are exposed to the various irritants of the oral milieu—bacteria, saliva, food
debris, and atmospheric air.
• After a protective dressing is inserted into the affected socket
• The dressing should serve not only as a covering mantle for the denuded bone but also as a
vehicle whereby appropriate anodynes can be brought into close contact with the alveolar and
thus obtund the pain emanating from exposed nerve endings.

14-04-2018 276
Oil of cloves is probably the original material, but
• eugenol,
• guaiacol,
• benzocaine,
• polyethylene glycol,
• lignocaine,
• domiphen bromide,
• zinc oxide,
• whitehead’s varnish,
• thymol iodide,
and many other substances have been used.
An agent that has proven topical anodyne properties and is not unduly irritating or caustic to the oral
tissues is all that is needed. The agent need not be complicated, and, as is so often the case, the
simpler the method, the better, so long as it is effective.

14-04-2018 277
A common formula that has been used with much success is as follows:
Eugenol 46%
Balsam of Peru 46%
Chlorobutanol 4%
Benzocaine 4%

14-04-2018 278
ALVOGYL
• most widely used palliative treatment.
• The alvogyl contains
❑ Butamben – 25.7gm
❑ Idoform – 15.8gm
❑ Eugenol- 13.7 gm
❑ Phenqhwer- 3.5 gm
• Eugenol inhibits the inflammatory process and
provide analgesic effects by inhibiting the actions
of prostaglandins.

14-04-2018 279
NERVE INJURIES
• 0.6-5% of all the third molar surgeries are involved with nerve damages of which 0.2%
are irreversible
• IAN: immediate disturbance - 4-5% (1.3-7.8%)
permanent disturbances - <1% (0-2.2%)
• Lingual N: immediate - 0.2-22%
permanent - 0-2%
• 96% IAN injuries show spontaneous recovery within 9 months, better than lingual nerve
which is about 87%
• Beyond 2yrs recovery is unlikely

14-04-2018 280
The incidence of neurologic injuries from third molar surgery may be related to multiple factors
such as:
a. Experience of the surgeon
b. Proximity of tooth to the inferior alveolar nerve (IAN)
c. Deep horizontal and distoangular impactions
d. Surgery performed under general anesthesia (GA)-
e. Patients age over 35 years
f. Completely formed roots
g. Depth of impaction
h. Use of rotary instruments
i. Surgical sectioning of tooth

14-04-2018 282
IANI-RISK REDUCING PROCEDURES

14-04-2018 283
CORONECTOMY
• A method of removing the crown of a tooth but leaving the roots untouched, which may be intimately
related with the inferior alveolar nerve, so that the possibility of nerve injury is reduced.
• first proposed in 1984 by Ecuyer and Debien.
• Also known as intentional partial odontoectomy, partial root removal and deliberate vital root
retention
BASIS FOR CORONECTOMY
It is common practice for broken fragments of the root of vital teeth to be left in place and most heal
uneventfully.
• Renton et al.and Leung et al. (randomised clinical trial), Hatano et al. (case control study) and
O’Riordan (retrospective study) provided evidence that coronectomy decreases the risk of IDNI
when compared to traditional extraction of MTMs

14-04-2018 284
Coronectomy:A, cutting crown below cement-enamel junction (arrow);
B, trimming cutted surface to less than 3 to 4 mm below alveolar crest.

14-04-2018 286
FATE AFTER CORONECTOMY
• Bone formation over the retained root fragment.
• Root migration is more in distoangular impactions and in older individuals
• Dry socket can be treated in the conventional manner with irrigation and dressing, if it
occurs.
• There does not appear to be any need to treat the exposed pulp of the tooth.

14-04-2018 287
PREOPERATIVELY 1 WEEK POSTOPERATIVELY
36 MONTHS POSTOPERATIVELY

14-04-2018 288
CASES TO AVOID
• Teeth with associated infection, particularly infection involving the root portion
• Teeth that are mobile
• Teeth that are horizontally impacted along the course of the inferior alveolar nerve
DRAWBACKS OF CORONECTOMY
• Root walk out during surgery(FAILED CORONECTOMY)
• deep periodontal pockets on the distal of the second molar,
• delayed postoperative root migration with the possible need of a second procedure
• postoperative pain
• dry socket
• infection

14-04-2018 289
RESISTANCE TO THE ACCEPTANCE BECAUSE
• concern about leaving a large section of root in the
mandible.
• Retained root may develop a radicular cyst leading to
further surgery and morbidity.
• post-operative infections
• root eruption leading to reoperation

14-04-2018 290
ORTHODONTIC EXTRUSION
•Risk of direct trauma to IAN is eliminated
•A potential problem with this technique is soft
tissue damage from impingement on the
mucosa of the cheek and the gingva.
•Difficult in working in this area because the
action of the masseter muscle leads to cheek
compression against the orthodontic
appliances
• no value in case of ankylosed teeth.
•It is time consuming and not always
successful

14-04-2018 291
PERICORONAL OSTECTOMY
The removal of the overlying bone to allow for the tooth to erupt away from the IAN,
in cases of incomplete root formation in younger patients 14 to 18 years old

14-04-2018 292
ACCIDENTAL DISPLACEMENT OF THIRD MOLARS
CAUSES
• Excessive apical force during the use of elevators .
• incorrect surgical technique.
• In mandibular third molar, the thinness of the lingual
cortical bone predisposes to displacement in a lingual
direction.
• Distolingual angulation of the tooth predisposes to the
displacement.

Impaction

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