The document provides an overview of the surgical anatomy of the mandible. It discusses the parts and features of the mandible, including the body, rami, coronoid and condylar processes. It details the growth and development of the mandible from the prenatal period through adulthood. Key anatomical structures are described, such as ligaments, muscles, nerves, blood vessels and lymph nodes associated with the mandible. Clinical considerations for surgical procedures involving the mandible are also mentioned.

1. SURGICALANATOMY OF
MANDIBLE
SURGICAL ANATOMY OF MANDIBLE

2. CONTENTS :
 Introduction
 Anatomy of mandible
 -parts of mandible
 -body of mandible
 FEATURES OF EXTERNAL SURFACE
OF BODY
 FEATURES OF INTERNAL SURFACE OF
BODY
 Growth & development of mandible
 OSSIFICATION
 Sex & age determination
 Attachments & relations
 Muscles controlling mandible
 Nerve supply of mandible
 Blood supply of mandible
 Lymphatic’s
 Anatomical spaces
 Clinical and antomical
consideration in mandible for
surgical procedure.
 Surgical consideration in implant.
 Conclusion.
 Reference.

3. INTRODUCTION :
 Mandible is the bone of lower jaw.
 The word mandible derived from Latin word mandibula-"jawbone" or inferior
maxillary bone.
 Only movable bone in the skull.
 It provides structural and protective support for the oral cavity.
 The mandible is articulated in ball and socket fashion at the condylar process.
 Strength resides in its dense cortical plates

4. SURGICAL ANATOMY
knowledge of anatomical facts
which have local significance in
relation to surgical therapy
 Primary emphasis is placed on an
understanding and awareness of important
structures that may be encountered during
surgery or which place limits on the nature of
the planned surgery, rather than on a detailed
and precise knowledge of systematic anatomy.

5. ANATOMY MANDIBLE :
PARTS OF
MANDIBLE
BODY OF
THE
MANDIBLE
RAMI
BORDERS
EXETERN
AL
INTERNAL
SURFACES
UPPER
LOWER

6.  Symphysis Menti: faint median ridge on external surface of body.
 Mental Protuberance-symphysis menti expands below into a triangular elevation
 Mental Tubercles- the base limit of point of chin on each side
 Mental foramen: below premolar teeth; provides passage to mental nerve and vessels
 External Oblique line: continuation of anterior border of ramus, runs downwards and
forwards towards mental tubercle.
 Incisive fossa: shallow depression just below incisor teeth.
FEATURES OF EXTERNAL SURFACE OF BODY

8.  Genial tubercles-inner aspect of symphysis menti possesses four tubercles
 Mylohyoid line-prominent oblique ridge that runs obliquely downwards and
forwards from behind the 3rd molar tooth to the symphysis menti below the genial
tubercles
 Submandibular fossa-slightly hollowed out area below the posterior part of the
mylohyoid line and lodges submandibular gland
 Sublingual fossa-shallow area above the anterior part of the mylohyoid line and
lodges sublingual gland.
 Mylohyoid groove-below the posterior end of the mylohyoid line
 Digastric fossa- Inferior border or base of the mandible presents a small
depression

10. Body ;Superior & Inferior borders
• The upper border, the alveolar part which lodges the teeth.
The lower border ,the base extends
posteriolaterally from the symphysis into
that of ramus behind the third molar.

11. RAMUS OF MANDIBLE
Is a quadrilateral vertical plate of bone that
projects upwards from posterior part of
body.
FEATURES:
2 surfaces: lateral and medial
4 borders: Superior, inferior, anterior and
posterior
2 processes: Coronoid
and condylar processes

12. RAMUS :Lateral surface/external surface:
Flat and bears a number of oblique ridges

13. RAMUS : Medial surface/Internal surface
Mandibular foramen
Lingula
Mylohyoid groove

14. CORONOID PROCESS

15. RAMUS :CONDYLAR PROCESS

16. GROWTH OF MANDIBLE
PRENATAL

17. • 4th week of intra-uterine life,a
prominent bulge appears on
the ventral aspect of the
embryo
• Below the bulge a shallow
depression-----the primitive
mouth --------- stomodeum.
• The floor of the stomodeum is
formed by the buccopharyngeal
membrane that separates the
stomodeum from the foregut
PRENATAL

26. INTRAMEMBRANOUS
BONE FORMATION
The first structure to develop in the primodium of the lower
jaw is the mandibular division of trigeminal nerve that precedes
the mesenchymal condensation forming the first [mandibular]
arch.
At around 36 – -38
days of intrauterine life
there is
ectomesenchymal
condensation
Some mesenchymal cells
enlarges , acquire a
basophilic cytoplasm and
form osteoblasts
These osteoblasts secrete
a gelatinous matrix called
osteoid and result in
ossification of an
osteogenic membrane.

27. The resulting intramembranous
bone lies lateral to meckel’s
cartilage of first [mandibular ]
arch.
In the 6th week of the
intrauterine life a single
ossification centre for each
half of the mandible arises
in the bifurcation of inferior
alveolar nerve into mental
and incisive branches

28. During 7th week of intrauterine life
bone begin to develop lateral to
meckel’s cartilage & continues until the
posterior aspect is covered with bone.
Between 8th & 12th week of
intrauterine life mandibular growth
accelerate , as a result mandibular
length increases
Ossification stops at a piont ,
which later become mandibular
lingula, the remaining part of
meckels cartilage continues to
form sphenomandibular ligament
& spinous process of sphenoid.
Secondary accessory cartilage appear
between 10th & 14th week of intrauterine
life to form head of condyle , part of
coronoid process & mental protuberance.

30. ENDROCHONDRAL
BONE FORMATION
Endrocondral bone formation is
seen in 3 areas of mandible
1)The condylar process
2) The coronoid process
3) The mental process
THE CONDYLAR
PROCESS
At 5th week of intrauterine life , an area of mesenchymal
condensation is seen above the ventral part of developing
mandible
At about 10th week it develops in cone
shaped cartilage.
It migrate inferior & fuses with mandi bular
ramus at about 4 month

31. This cone shaped cartilage is
replaced by bone but its upper end
persists acting as growth cartilage
& articular cartilage

32. THE CORONOID
PROCESS
Secondary accessory cartilage appear
in region of coronoid process at about
10- 14 week of intrauterine life.
This cartilage become incorporated
into expanding intramembranous
bone of ramus & dissapear before
birth

33. THE MENTAL REGION
In mental region , on either side of
symphysis , one or two small
cartilage appear and ossify in
seventh week of intrauterine life to
become mental ossicles.
These ossicles become incorporated
into intramembranous bone when
symphysis ossify completely

34. NEONATAL
MANDIBLE
Rami - low and wide
Coronoid - large and
projects above the condyle.
Body - open shell
containing tooth buds.
Mandibular - low in body

35. GROWTH OF
MANDIBLE
In adults developmentally and
functionally divided into –
• Body
• Condyle
• Coronoid
• Ramus
• Angle
• Lingual tuberosity
• Chin
Condylar cartilage
Posterior border of rami
Alveolar ridge
Symphysis – limited.
MAJOR GROWTH SITES

36. RAMUS
The ramus moves progressively
posterior by a combination Of
deposition and resorption
Resorption occur on the anterior
part
deposition occur on the posterior
region
POSTERIOR DIRECTION

37. CORPUS /BODY OF MANDIBLE
Body of mandible lengthens as the ramus
exhibits bone deposition on the posterior
aspect and resorption on the anterior
aspect.

38. ANGLE OF MANDIBLE
 On the lingual side :
 Resorption takes place on the posterio-inferior
aspect.
• Deposition occurs on the anterio- superior
aspect.
 On the buccal side:
 Resorption occurs on the anterio-superior
part.
 Deposition occurs on the posterio-inferior
part.
 Flaring of the angle of the mandible as age
advances

39. THE LINGUAL TUBEROSITY
Grows posterior and medial by
deposition
Resorptive field below –lingual fossa

40. THE ALVEOLAR
PROCESS
As the teeth erupt the alveolar
process develops and increase in
height by bone deposition at the
margins.
the height and thickness of the
body of the mandible.
absence of teeth -- fails to
develop and it resorb

41. THE CONDYLE
The role of condyle in the growth
of mandible has remained
controversy.
growth of soft tissue including the
muscles and connective tissue carries
the mandible forward away from the
cranial base (cary awray phenomenon)

42. THE THE CORONOID PROCESS
ONOID PROCESS
It follows Enlow”s
“V” principle
In longitudinal section –
from posterior aspect,
deposition occurs on the
lingual surface of the left
and right coronoid
process

43. THE THE CHIN
1-2 YR – Chin prominence is
seen
The mental protuberance
forms by bone deposition.
The change in the contour
occur by following two
mechanism:
1.The area just above the
chin and the base of the
alveolar process, is a
resorptive.
2. There is forward
translation of chin as
mandible grows forward

46. LIGAMENTS ATTACHED TO
MANDIBLE
1. Stylomandibular ligament- attached to angle of
mandible
2. Temporomandibular- attached to lateral aspect
of neck of mandible
3. Sphenomandibular ligament- attached to
lingula
4. Pterygomandibular raphae/ligament- attached
behind the last molar tooth to upper end of
mylohyoid line.

48. MUSCLES CONTROLLING MANDIBULAR
MOVEMENTS
VERTICAL MOVEMENTS
Elevate mandible:
• Masseter
• Temporalis
• Medial pterygoid
Depress mandible:
• Lateral pteyigoid
• Geniohyoid
• Ant. Diagastric
• Mylohyoid
ACCESSORY
MUSCLES
 -GENIOHYOID
 ANT DIAGASTRIC
 MYLOHYOID
 STYLOHYOID
MUSCLES OF
MASTICATION
• MASSETER
• TEMPORALIS
• MEDIAL PTERYGOID
• LATERAL
PTERYGOID

49. SIDE TO SIDE MOVEMENT
Lateral pterygoid
Medial pterygoid
SAGITTAL MOVEMENTS
Protrusion
Lat. & medial pterygoid together
Retrusion
Post. Fibres of temporalis

50. MUSCLES OF MASTICATION

52. SUPRAHYOID MUSCLES :
•Importance: facial deformities such as mandibular retrognathia and
open bite ,the actions of suprahyoid muscle maybe determinantal to the
stability of the surgical repairs, and therefore they may have to be
partially released along their inferior mandibular insertions
• ( Steinhauser,1973)

53. FORAMINAAND RELATION
1) Mental foramina - mental nerve
and vessels
2) Mandibular notch - massetric
nerve and vessels
3) Medial side of neck - auriculo
temporal nerve
4) Mylohyoid groove - mylohyoid
nerve and vessels
5) Mylohyoid groove in front of
ramus - lingual nerve
6) Mandibular canal and foramina
- inferior alveolar nerve and
vessels

54. TEMPORAMANDIBULAR JOINT
This is a synovial joint of condylar
variety.
ARTICULAR SURFACES:
The upper articular surface is
formed by the following part of
temporal bone:
A:articular tubercle
B: anterior part of mandibular fossa
The inferior articular surface is
formed by the head of the
mandible.
The articular surface is covered
with fibro cartilage.
The joint cavity is divided into
upper and lower parts by an intra –
articular disc.

56. NERVE SUPPY OF MANDIBLE
1. Lingual nerve- runs on the inner surface of body close
to medial side of root of 3rd molar.
2. Inferior alveolar nerve- enters mandibular foramen and
pass through mandibular canal.
3. Mylohyoid nerve- runs in the mylohyoid groove.
4. Mental nerve- comes out of mental foramen.
5. Nerve to masseter- runs through mandibular notch.
6. Auriculo temporal- runs to medial side of neck.
7. Marginal mandibular nerve- across the lower border
of mandible.

58. BLOOD SUPPLY OF THE MANDIBLE
Arterial supply
• Mainly by Maxillary artery, Branch of external carotid artery ,by its
branches, mainly through inferior alveolar artery

60. As the external carotid artery
ascends the face, it will branch
into six arteries: the superior
thyroid artery, lingual artery,
ascending pharyngeal artery,
facial artery, occipital artery,
and posterior auricular artery.
The external carotid artery
will terminate and become
the superficial temporal
artery and the maxillary
artery.
The maxillary artery is what branches into
the inferior alveolar artery
The inferior alveolar artery is a small muscular artery that
branches from the first portion of the maxillary artery.
The course of the inferior alveolar artery is similar to the
inferior alveolar nerve

61. LINGUAL ARTERY
The lingual artery arises from the anterior surface of
the external carotid artery at the level of the hyoid bone
between the superior thyroid and facial arteries
It first runs upward and medialward to the greater
cornua of hyoid bone.
It then passes deep to the hyoglossal muscle extending
downward and forward to form a characteristic loop
Finallly ascending almost perpendicularly to the tongue
turns forward on its lower surface as far as the tip
under the deep lingual artery .

62. • The preparation of a grafting osteotomy
in the midline can potentially resect
these blood vessels if they fall in the
path of the vertical preparation.
• If this occurs, the sectioned extension of
the lingual artery can prolapse back into
the floor of the mouth.
• The severed vessel may release arterial
blood flow in the sublingual space,
potentially raising the tongue to a point
that compromises the airway.
• Immediate emergency intervention to
maintain the airway is critical, and in
some cases this requires use of a
tracheostomy until the blood flow has
been controlled.

63. FACIAL ARTERY
The facial artery arises from the anterior surface of the
external carotid artery slightly above the origin of the
lingual artery
and has a tortuous route along the nasolabial fold
towards the medial canthus of the eye. It moves beneath
the digastric and stylohyoid muscles and it will pass
through the submandibular gland.
The artery will then curve over the body of the mandible
(deep to platysma), as the anteroinferior angle of the
masseter, will ascend forwards and upwards across the
cheek, to the angle of the mouth and along the side of
the nose. It terminates near the medial aspect of the eye.
In the region of the head, the facial artery runs roughly
parallel to the facial vein, although not adjacent to it.

64. Venous supply of
mandible
Drains into
•Internal jugular vein
• external jugular
vein through
maxillary
vein
•Facial vein and
pterygoid plexus

65. LYMPHATICS
Most of the mandible & lower teeth drain into the submandibular
group of lymph nodes .
Except a small wedge in the symphysis region & the lower incisors
which drain into the submental group of lymph nodes.
From the submental group the lymph drains to the submandibular
group of nodes.
Most of the submandibular nodes ultimately drain to the jugulo-
omohyoid group of deep cervical lymph nodes.
Few extremely posterior submandibular nodes drain to jugulo-
digastric group of deep cervical lymph nodes.

67. ANATOMICAL SPACE

70. SUBMENTAL SPACE.
Boundaries
Deep or lateral : Anterior belly of
digastric
Superficial or medial : Investing
layer of deep cervical fascia
Superior : Mylohyoid muscle
Inferior: Investing layer of deep
cervical fascia
Anterior : Inferior border of
mandible
Posterior : Hyoid bone

71. CLINICAL FEATURES
Extraoral findigs
 Distinct,firm swelling in midline,beneath the chin.
 Skin overlying the swellig is board like and taut.
 Fluctuation may be present.
Intraoral findings
 The anterior teet,are eiether nonvital,fractured or carious.
 The offending tooth may exhibit tenderness to percussionn and may
show mobility .
 The patient may experience considerable discomfort on swallowing.

73. SUBLINGUAL SPACE
sub mucosal connective tissue of the floor of
the mouth.
Contains :
sublingual gland Wharton's Duct
The commonest cause :
• dental caries
• sialoadenitis
• infection tracking via the submandibular
duct from the submandibular gland
The posterior border of the sublingual space
is open and communicate with
submandibular space

74.  Inferiorly: Mylohyoid muscle
 Laterally : Medial surface of
mandible
 Medially : Hyoglossus,genioglossus
& geniohyoid
 Posteriorly :Submandibular space
 Laterally and inferiorly : Mylohyoid
muscle & lingual side of mandible

75. CLINICAL FEATURES

77. SUBMANDIBULAR SPACE
If the apex of the tooth is inferior to the muscle(third molar),
the submandibular space is involved

78.  Anteromedially: mylohyoid muscle
 Posteromedially : hyoglossus muscle
 Superolaterally : medial surface of
mandible
 Anterolaterally: anterior belly of digastric
 Posteromedially : posterior elly of
digastric,stylohyoid & stylopharyngeus
muscle
 Superficial : platysma and skin
 Deep : Mylohyoid,hyoglossus & superior
constrictor

79. Causes:
Infection from mandibular molar
Infection from sublingual space
Infection from middle third of
tongue
Posterior part of floor of the mouth
From submental space/submental
lymph
nodes
Infection from the submandibular
gland.
CONTENTS:
Superficial portion of
submandibular gland.
Submental and submandibular
lymph nodes.
Facial artery and vein
Fat and belly of diagastric.

80. INCISION AND
DRAINAGE

81. PTERYGO -MANDIBULAR SPACE
Superiorly : lower head of lateral
pterygoid muscle
Laterally : medial surface of ramus.
Medially: medial pterygoid muscle
Posteriorly :deep part of parotid
Anteriorly :pterygomandibular raphe

82. Infection primarily from the third molar or
from infected needle track.
CONTENTS:
Inferior alveolar neurovascular
bundle.
Lingual
Auriculotemporal nerve
Mylohyoid nerve and vessels

83. PARAPHARYNGEAL SPACE
The parapharyngeal space lies at the
base of the skull medial to the
medial pterygoid muscle and is
delineated by fascial membranes.
It communicates anteriorly - buccal,
sublingual, and pterygomandibular
spaces.
Medially with the
retropharyngeal space.
Inferiorly with the spaces of the
neck.

84. CLINICALAND ANTOMICAL CONSIDERATION IN
MANDIBLE FOR SURGICAL PROCEDURE.
INFERIOR ALVEOLAR NERVE
BLOCK
LANDMARKS
Coronoid notch
Pterygomandibular raphe
Occlusal plane of mandibular posteriors

85. LANDMARKS
Coronoid notch
Pterygomandibular raphe
Occlusal plane of mandibular
posteriors
TECHNIQUE: 3 Parameter to consider
(1) the height of the injection
(2) the anteroposterior placement of the
needle
(3) the depth of penetration
Depoite :
IAN :1.5
Lingual nerve:.2

86. COMPLICATIONS
Hematoma
Trismus
Facial paralysis
Due to L.A penetration to
parotid gland capsule
Rx:Transient ,self
correcting with in 3 hr or
less
CAUSES:
 Trauma to
muscle
Or blood vessels
in infratemporal
fossa.
 Contaminated
LA
large volume of

87. BUCCAL NERVE BLOCK
Anesthetized: Soft tissue and periosteum
buccal to the mandibular molar teeth
Insertion: Distal, Buccal of last molar
Land mark: Mucobuccal
fold
Deposit : 0.3mL

88. MENTAL NERVE BLOCK
Anesthetized :Provides sensory input for
the lower lip skin, mucous membrane,
pulpal/alveolar tissue for the premolars,
canine, and incisors on side blocked
AREA OF INJECTION: Mucobuccal fold
at or anterior to the mental foramen. This
lies between the mandibular premolars
Deposite: 0.5-1.ml of
L.A

89. SURGICAL ANATOMY
 Location of muscle
attachments
 Thinness /absence of
radicular bone
Mentalis muscle
→ Prevent
surgeon from ↑
zone of attached
gingiva /
deepening the
vestibule
ANTERIOR FACIAL REGION

90.  The plate of bone overlying the facial and lingual root
surfaces of the anterior teeth is usually quite thin.
 When surgical therapy is required in this area, a
technique may be chosen which leaves the bone covered
with periosteum and connective tissue to
 prevent possible postoperative osseous and gingival
recession over these roots.
 A prominent mental tuberosity on occasion may also
limit the depth of the vestibule by forming a flat
projection in the midline of the mandible. Deepening of
the vestibular fornix may not be possible in such a

91. As mucogingival
problems are very
common in the anterior
region.
The coronal level of the
muscle attachment is
often approached in
attempts to apically
position the
mucogingival junction.
Since it is a thick
attachment, its more
coronal fibers may be
removed to gain the
necessary depth for
adequate surgical
results.

92. Large or high Genial
tubercle upon which
several muscles attach
Tubercle could
approximate deep
osseous defects →
Prevent lingual osseous
Recontouring during
periodontal surgery
ANTERIOR LINGUAL REGION

93. POSTERIOR FACIAL REGION
Periodontal surgery in the mandibular posterior facial
region is most often complicated by the presence of a
prominent external oblique ridge
If the periodontal osseous defects extend below
the level of the ridge, osseous recontouring in
an attempt to eliminate these defects would
require extensive and unwanted removal of
large amounts of bone.

94. Loose areolar
mucosa found
attached by a
narrow ring of
gingiva – distal
surface of last
Molar

95. Surgical correction of distal defects
in these areas which attempt to widen
the band of attached tissue are
hampered by the vertical bony
prominence of the ramus.

96. Buccinator
muscle forms
medial
wall of buccal
space
If perforated while
elevating a Buccal
flap → Buccal
space entered →
Infection
Buccal space ↔
Parapharyngeal
space → Spread
into other spaces (
Head & Neck )
Thin attachment
BM
Limit
extension
of
vestibule

97.  An additional operative hazard exists in the molar region where the
facial artery passes under the inferior border of the mandible.
 The vessel normally continues its course deep within the cheek and is
not disturbed while elevating mucosal flaps from the mandible.

98. .
MENTAL FORAMEN

99. POSTERIOR LINGUAL
REGION
An unusually wide mylohyoid ridge or a lingual
mandibular torus offer the same complications in
osseous surgery as previously mentioned
concerning the oblique ridge on the facial surface.

100. The while performing surgery on the superficial
structures which lie just under the thin mucosa which
forms the floor
of the mouth.
The lingual nerve is most easily damaged as it
lies very close to the mucosal surface in the
region of the second and third molars.
Major precaution --lingual aspect of the
mandible is to avoid incising

101. Whenever the attached gingiva is
elevated from the lingual aspect
of a mandible, or when the
mucosal lining of the floor of the
mouth is perforated, the
sublingual space .
Submandibular gland and
duct are less likely to be
violated because of their
deeper position.
mylohyoid muscle attachment would
result in opening into the submandibular

102. With wide zones of keratinized gingiva present
or a short mandible, a sulcular incision may be used.
A periosteal elevator is used to reflect the mucoperiosteal flap
toward the base of the mandible to the level of the “pogonion” (most
anterior point of mandible), thus ensuring that the inferior border
of the mandible remains intact.
This will leave the most facial aspect of the periosteal attachment
intact and prevent “ptosis” of the chin by avoiding “degloving”
of the mandible.

103. MANDIBULAR FRACTURE
INCIDENCE OF MANDIBULAR FRACTURES
•Body fractures 33.6%
•Subcondylar fracture 33.4%
•Fractures at the angle 17.4%
•Alveolar fractures 6.7%
•Ramus fractures 5.4%
•Midline fractures 2.9%
•Fracture of coronoid process 1.3%
Oikarinen & Malmstrom 1969

104. TYPES OF FRACTURE
 Simple
Greenstick fracture (rare, exclusively in
children)
Fracture with no displacement (Linear)
Fracture with minimal displacement
 Displaced fracture
 Comminuted fracture
Extensive breakage with possible
bone and soft tissue loss
 Compound fracture
Severe and tooth bearing area fractures
Pathological fracture
(osteomyelities, neoplasm and
generalized skeletal disease)

106. Ludwig’s angina: Perimandibular
spaces are bilaterally involved in an
infection.
Rapidly spreading
cellulitis that can
obstruct the airway
and it spreads
posteriorly to the
deep fascial spaces
of the neck.
Patients usually
has sever
indurated
swelling with
:Tongue
elevation
Trismus
Drooling
Difficulty in
swallowing and
breathing
Rx:
I&D
Antibiotics

113. SIGNIFICANCE OF LINGUAL NERVE
DURING PERIODONTAL/IMPLANT
SURGERY
• The lingual nerve is a branch of the mandibular nerve. This nerve
provides sensory innervation to the mucous membranes of the
anterior two thirds of the tongue and lingual tissues.
• The proximity of this nerve to the mandibular third molar region is a
concern when performing flap surgery in this area.
• On average, it is located 3 mm apical to the osseous crest and 2 mm
horizontally from the lingual cortical plate in the third molar area.
BEHNIA H et al 2005

114. • To reduce the chance of injuring this
nerve, some procedures have been
advocated.Incisions distal to the third
molar should be made on the buccal
aspect of the ridge and always on the
bone. The elevator should be used to
protect the nerve in the flap, and the
tissue should be managed gently.

115. AGE DETERMINATION OF MANDIBLE
Mostly determined by
1) Eruption of temporary & permanent teeth
2) Condition of socket of teeth

116. 1) Mental
foramena
Near to lower
border
midway Near upper
border
2)Angle of
mandible
Obtuse ( near 180 ) about Right
angle(110 -120)
Obtuse (140)
3) Coronoid &
condyloid process
Coronoid is larger
& above condyloid
Condyloid is above
coronoid
Condyloid is above
coronoid
4)Mandibular canal Above mylohyoid
line
Parallel to
mylohyoid line
Run close to upper
border
5)Symphysis menti Present & 2 halves
are united by
fibrous band
As faint ridge only
on upper part
Not recognizable
or absent

122. SURGICAL CONSIDERATION FOR IMPLANT
Implants can strengthen the jawline and create a
more balanced facial structure by augmenting
the mandibular body, angle, and ramus

124. MANDIBULAR ANTERIOR
REGION
•Minimum of 7 mm from
inferior border of
mandible to the crestal
ridge is needed
•In resorbed ridge
mental foramina located
on top of the ridge;care is
necessary to prevent
damage to it and possible
paresthesia.
•This region between
mental foramina has
adequate bone for 4-6
implants.
MYLOHYOID RIDGE
Careful palpation – a
concavity below the
mylohyoid ridge.
Implant placed in the
posterior mandible are at
risk of entering this
region,which is highly
vascularized ,with
resultant risk of
haemorrhage.

125. APPLIED ANATOMY
-implant installation planning should be done on three-dimensional edentulous
jaw segment (EJS) pattern
-EJS consists of alveolar and basal bone
-EJS describes planned implant bed relation to present anatomical borders such
as mandibular vital structures
• The vertical dimension of the planned implant site in
mandible is determined by the distance between
crestal ridge of the alveolar process and mandibular
vital structures (EJS height) -mental foramen (MF) ,
-mandibular canal (MC),
-mandibular incisive canal
(MIC),
-anterior loop of mental
nerve (AL)
• horizontal dimensions are determined by the

126. Mental Foramen(MF)
-round/oval
-2.5mm-5.5mm diameter
-location
I LPM –caucasians
II LPM- Mongoloids
- Vertcal positio irt premolars
I PM- 38.6% coronal
15.4% apex
46% below apex
II PM – 24.5% coronal
13.9% apex
61.6% below apex

127. AGE CHANGES IN LOCATION OF
MANDIBULAR FORAMEN
• For greater accuracy in anesthetic procedures, dentists
should relate the locational changes in the mandibular
foramen with age when performing block anesthesia for
the inferior alveolar nerve
• 3 yrs …….. 4.12 mm below (mandibular
occlusal plane)
• 9 yrs …….. At level
• Adult ……. 4.16 mm above
• Old age ….. Further ABOVE

128. Mandibular zone of safety( Misch
1980)
- An area with in the bone that can safely support
implants without fear of impingement on the
mandibular neuro vascular bundle

129. ANOMALIES OF
DEVELOPMENT
CONGENITAL
• Agnathia
• micrognathia
• Macrognathia
• facial hemihypertrophy
• Facial hemiatropy
DEVELOPMENTAL
• Infantile cortical
hyperostosis
• Achondroplasia
• Torus mandibularis
• Stafne’s cyst
• Odontogenic cyst

130. Agnathia
Micrognathia
Macrognathia
Hemifacial
hypertrophy

131. Infantile cortical
hyperostosis
Stafne cyst
Mandibular tori

132. Some of the syndromes associated with mandibular abnorma
• Down’s syndrome
•Marfan syndrome
•turner syndrome
•Klinfelter syndrome
•Pierre-robin syndrome
•Treacher- collins syndrome

133. Marfan
syndrome Pierre-robin
syndrome
Treacher- collins
syndrome

134. PATHOLOGY OF JAW
ODONTOGENIC CYSTS
Inflammatory. Radicular cysts
Developmental: Dentigerous cysts
Lateral periodontal cysts
Odontogenic keratocyst
Radicular cysts
OKC

135. OSTEORADIONECROSIS (ORN) – INJURY TO BONE
Osteoradionecrosis (ORN) is
a condition of nonvital
bone in a site of radiation
injury.
The absence of reserve
reparative capacity is a
result of the prior radiation
injury.
trauma such
as denture-
related
injury, ulcers,
or tooth
extraction
GRADE I:Bone exposure
respond to HBO
GRADE II: Bone exposure
not respond to HBO,need
sequestromy/
saucerisation.
GRADE III: pathological
fracture

136. CONCLUSION
The mandibular movement is considered as the chewing apparatus of masticatory
system. All the events taking place during development of mandible play an
important role in determining the final structure of mandible, any deviation of
which can give rise to various abnormalties in oro facial region.
Finally, three things we should keep in mind: (a) constantly revise your
knowledge of anatomy; (b) constantly think of the local anatomy in relation to
injury and disease; and (c) never take a knife in your hand without picturing in
your mind's eye the structures in and adjacent to your operative field, however
small that field may be .

137. REFERENCES
• -Gray’s anatomy ; williams ;37th edition
• Human anatomy ; Chaurasia B.D. 3RD Edition
• Human embryology; Inderbir singh ;7th edition
• Killey’s fracture of mandible ;Peter bank: 4th edition
• Anatomical considerations in periodontal surgery by micheal a et al vol 42 jop 1991
• SURGICAL ANATOMY OF THE JAWS
• Lecture delivered at the Royal College of Surgeons of England on 28th May 1963 by Ian H.
Heslop, M.B., B.S., B.D.S., F.D.S.R.C.S.

138. • Vishram Singh Textbook of Anatomy -Head, Neck, and Brain- 2nd edition
• -Juodzbalys G, Wang HL. Guidelines for the Identification of the Mandibular Vital
Structures: Practical Clinical Applications of Anatomy and Radiological Examination
Methods. J Oral Maxillofac Res 2010 (Apr-Jun);1(2):e1 doi:10.5037/jomr.2010.1201
• --Greenstein G, Cavallaro J, Tarnow D. Practical application of anatomy for the dental
implant surgeon. J Periodontol. 2008;79(10):1833-1846. doi:10.1902/jop.2008.080086
• John Nguyen; Hieu Duong. Anatomy, Head and Neck, Inferior Alveolar Arteries

139. THANK YOU