The Middle Third Of The Facial Skeleton Is Defined As An Area Bounded, Superiorly –Line Drawn Across The skull from the Zygomatico frontal Suture across the Frontonasal & Frontomaxillary sutures to the Zygomaticofrontal suture on the opposite side Inferiorly –by the occlusal plane of the upper teeth./upper alveolar ridge. Posteriorly-The region is demarcated by the sphenoethmoidal junction but includes the free margin of the pterygoid laminae of the sphenoid bone inferiorly. Inferiorly –by the occlusal plane of the upper teeth./upper alveolar ridge. Posteriorly-The region is demarcated by the sphenoethmoidal junction but includes the free margin of the pterygoid laminae of the sphenoid bone inferiorly. It is made up of the following bones: 1. Two maxillae 2. Tw o palatine bones 3. Two zygomatic bones and their temporal processes 4. Two zygomatic processes of the temporal bone 5. Two nasal bones this presentation describes about each bone individually and its applied anatomy

1. Presenter: Dr. Shalini Sampreethi A MDS
Assistant professor
Oral and Maxillofacial Surgery
MNR Dental College and Hospital

2.  INTRODUCTION
 EMBRYOLOGY
 BONES IN MID FACE
 ANATOMY OF MID – FACIAL BONES
 MAXILLARY SINUS
 APPLIED ANATOMY OF MIDFACE
 REFERENCES

4.  There are 10 bones in mid face
 PAIRED BONES:
 Maxillae
 Zygomatic bones
 Zygomatic process of the temporal
bone
 Palatine bones
 Nasal bones
 Lacrimal bones
 UNPAIRED BONES:
 Vomer
 Ethmoid &its attached bones
 Inferior conchae
 Pterigyoid plates of spenoid bones

6. Face is derived from the
following structure that
lie around the
stomatodaeum :
1.Fronto-nasal process
2.Mandibular arch of
each side

7. Ectodermal fronto-nasal
process shows bilateral
thickening called NASAL
PLACODESNA NASAL
PITS
Medial
nasal
process
Lateral
nasal
process
UPPER LIP
 LOWER LIP

8. When one or two maxillary process do
not fuse - medial nasal process ,
unilateral or bilateral cleft
Defective development of lowermost
part of fronto-nasal process  midline
defect of upper lip
When the two mandibular process don’t
fuse  lower lip may extend upto the jaw
Non fusion of maxillary process with
lateral nasal process gives the cleft running
from the medial angle of eye to
mouth(OBLIQUE FACIAL CLEFT) in this
nasolacrimal duct is not formed

9. Maxilla  Plalatal processes
2 palatal process + primitive
plate -fronto nasal process
palate
Palates process fuses + posterior
margins of primitive maxilla &
both the palatal process fuse with
each other
Later mesoderm of hard palate
undergoes intramembranous
ossification to form hard palated

10.  Inadequate fusion of maxillary & mandibular process
may give rise to MACROSTOMIA, lack of fusion may
lead to “LATERAL FACIAL CLEFT”where as
MICROSTOMIA is wise versa of it
 If the entire 1st arch is under deve
-eloped the promince of cheeks
May be lost &ear may be displaced
Ventrally& caudally.This called as
MANDIBULO-FACIAL DYSOSTO
-IS or FIRST ARCH SYNDROME

11. The body of the maxilla is
pyramidal in shape ,with its
directed medially at the nasal
surface & apex directed
laterally at zygomatic process .
It has 4 surfaces and encloses ,
the large cavity the “
MAXILLARY SINUS” the
surfaces are:
Anterior/facial surface
Posterior/infra-temporal
surface
Superior/orbital surface
Medial/nasal surface

12. Depression above incisor teeth,
the incisive fossa gives origin to
DEPRESSOR SEPTI
 Below the fossa it gives
INCISIVES, superio lateral to it
along the nasal notch there is a
origin of NASALIES
Lateral to canine fossa there is
depression gives LEVATOR ANGULI
ORIS
Above the canine fossa  Infra
orbital foramen  Infra orbital
nerves & vessels (paresthesia)
between the foramen &margin it
gives LEVATOR LABII SUPERIORIS

13. It is convex and directed
backwards and laterally
It forms the anterior wall of the
infra temporal fossa , separated
from the anterior surface by
zygomatic process &rounded
ridge which desends from the
process to 1st molar
Near the center gives 2 or 3
alveolar canals for posterior
superior alveolar nerves &vessel

14.  Postero inferiorly , there is a
rounded eminence , articulates
with pyramidal process of palatine
bones &gives origin to superficial
head of medial pterygoid muscle
( gagging of molar in lefort
fractutes)
 Above the maxillary tuberosity ,
the smooth surface forms anterior
wall of pterygopalatine fossa and is
grooved by maxillary nerve

15. Above the hiatus , parts of air
sinuses are completed by ethmoid
& lacrimal bones.
Below the hiatus  part of
inferior meatus of nose
Behind the hiatus artilculates
with perpendicular palatine bone
enclosing greater palatine canal
gurein`s sign in Lefort fracture
Infront of the hiatus,
nasolacrimal groove is converted to
naso lacrimal canal transmits
nasolacrimal duct to inferior –
meatus block in NOE Fractures

16. More anteriorly , an
oblique ridge forms the
conchal crest for
articulation with inferior
nasal conchae .
Above the crest shallow
depression forms the part
of the atrium of middle
meatus

17. Superior surface is smooth,
triangular & concave , form
greater part of the orbit.
Anterior border forms a part of
infra orbital margin medially, it
is continuous with lacrimal crest
of frontal process.
Posterior border it forms most
of the anterior margin of infra
orbital fissure , in the middle it
is notched by infra orbital
groove.

18. Medial border presents anteriorly
lacrimal notch which is converted into
naso lacrimal canal , behind the notch
border articulates lacrimal,
labyrinthine of ethmoid , orbital
process of palatine bones
The surface presents infra orbital
groove to infra orbital canal which
gives infra orbital foramen it gives infra
orbital nerves &vessels near midpoint
the canal gives off a branch canalis
sinvous, for passage of anterior
superior alveolar nerve and vessels
Infra oblique muscle arises from
depression just lateral to lacrimal
notch at anterio medial angle.

19. o There are four process of
maxilla :-
o The Zygomatic process
oThe Frontal process
oThe Alveolar process
oThe Palatine process

20. The zygomatic process is
pyramidal lateral projection on
which anterior, posterior and
superior surface of maxilla
converge.
In front and behind, it is
continous with corresponding
surfaces of the body , but
superiorly it is rough for
articulation with zygomatic
bone

21. I. The frontal process
projects upwards and
backwards to articulate
above with nasal margin of
frontal bone in front with
nasal bone , and behind
with lacrimal bone
II. Below the conchal crest ,
there lies the inferior
meatus of the nose with
nasolacrimal groove
ending just behind the
crest

22. 
The alveolar process forms half of
the alveolar arch, bears the sockets for
the roots of upper teeth.
Buccinator arises from the posterior
part of its outer surface extending up
to 1st molar teeth
A rough ridge , the maxillary torus
sometimes present on inner surface of
molar sockets

23. Palatine process is a thick horizontal
plate projecting medially from the lowest
part of the nasal surface.
 Inferior surface is concave,& 2palatine
process forms 3/4th of the bony palate . It
presents numerous vascular foramina&
pits for palatine glands posterio laterally ,
marked by 2 anterio posteriorly groove
for greater palatine vessels &anterior
palatine nerves
Groove between the nasal crest of 2
maxilla receives lower border of vomer

24. Anterior surface ends medially
into a deeply concave border
called “NASAL NOTCH ,
Posterior surface is convex.
 Alveolar border with the socket
faces downwards with its
convexity facing outwards
Fronto-nasal process is the
longest process facing upwards
Medial surface is marked by the
large irregular opening,the
MAXILLARY HIATUS.

25. 1. Superiorly , it articulates with 3 bones : The nasal,
frontal and lacrimal
2. Medially , it articulates with 5 bones, the ethmoid ,
inferior concha ,vomer, palatine and opposite maxilla
3. Laterally, it articulates with one bone, the zygoma

26. Maxilla ossifies in membrane from 3
centers, 1 for the maxilla proper & 2 for
os incisivus or premaxilla . The center
for maxillar proper appears above
canine fossa during 6th week of intra
uterine life.
Of 2 pre maxillary centers, main
centre appears above incisive fossa
during . The 2nd centre appears at the
ventral margin of nasal septum during
10th week & soon fuses with palatal
process of maxilla.

27.  Though pre maxilla begins to fuse with alveolar
process almost immediately after ossification begins.
 The evidence of pre maxilla as a separate bone may
persists until the middle decade

28.  At the birth:-
a) The transverse & anterio posterior diameter are each
more than vertical diameter.
b) Frontal process is well marked
c) Body consists of a little more than alveolar process tooth
socket reaching to floor of the orbit
d) Maxillary sinus is a mere furrow on lateral wall of the
nose
 In the adult:-
a) Vertical diameter is greatest due to development of
alveolar process & increases size of the sinus
 In the old:-
a) The bone reverts to infantile condition .Its height is
reduced as a result of absorption.

29. This voluminous but feater weight
bone comprises much of the roof of
nose, contributing minimally floor
of the anterior cranial fossa , and to
the medially wall of the orbit & thus
parts of lateral wall of the nose.
The perpendicular plate forms
body of the nasal septum & projects
above into the floor of the anterior
cranial fossa as the crista galli
through this olfactory nerves enters
the nose

30. The foramina contacts with dura matter above nasal
periostium below ( CSF rhinorrea)
Olfactory nerves, being the extension of the brain , do
not regenerate after division as the case with periferal
nerve , and post traumatic anosmia & it is perminant

31. They are also called as malar
bones.
Each zygomatic bone forms
the prominence of a cheek.
Forms lower outer margins of
orbits.
It is roughly quadrangular
having 3 surfaces and 5 borders

32. 1. Lateral/facial surface-zygomatico facial foramen
zygo maticus major
posteriorly & minor anteriorly
2. Postero medial/temporal surface- zygomatico
temporal foramen
3. Orbital surface- zygomatico orbital foramina
which represent the
openings of canals leading to zygomatico facial
and zygomatico temporal foramina

33.  FRONTAL PROCESS: A thick three sided process ; projects
upwards .Possesses:
i. 3surfaces: 1. anterior 2. posterior 3. lateral
ii. 3 borders: 1. anterior 2. posterior 3. medial
iii. 1 end : upper end, lower end is fused with the main part.
 Anterior surface: slightly convace ; continuous with
orbital surface of the body , i.e the main part of the bone
 Posterior surface: concave ; continuous with temporal
surface of the body
 Lateral surface: narrow & convex ;continuous with lateral
surface of bone

34.  TEMPORAL PROCESS: A small, triangular and
pointed process , projecting backwards from the
posterio inferior part of the bone.
 Presents: 1. serrated upper edge which articulates with
anterior end of zygomatic process of the temporal
bone thus completing the zygomatic arch.
2. lower non articular border : continuous with
posterio-inferior border of the main part. Gives origin
to some fibers of MASSETER .

36.  Two palatine bones lies together at the posterior part
of the nasal cavity between maxillae & pterygoid
processes of sphenoid bone; resembles the letter “L” in
shape.
 It helps to form
I. floor & lateral wall of nasal cavity .
II. Roof of oral cavity .
III. Floor of the orbit.
IV. Pterygopalatine & pterygoid fossae.
V. Inferior orbital fissure.

37. PARTS
2 plates : 1. Horizontral
2. Perpendicular.
3 processes : 1. Pyramidal
2. Orbital
3. Sphenoidal.

38.  They are two in number . Thin , paper like , rectangular bone
lying in the anterior part of the medial wall of orbit of its own
side between frontal process of maxilla in front and orbital plate
of labyrinth of the ethmoid bone behind .
 It is smallest & easily breakable of all cranial bones .
 Possesses : 2 surfaces : 1. lateral (orbital)
2. medial (nasal)
4 borders : 1. anterior 2. posterior
3.superior 4. inferior
• Lateral surface forms medial wall of orbit, posterior lacrimal
crest gives attachments to i,lacrimal fascia ii,origin to lacrimal
head of the ORBICULARIS ORIS .
• Lacrimal fossa the grooved lateral surface forms fossa for the
lodgement of lacrimal sac

40.  Two in number ; lie side by side between the frontal
processes of the two maxillae, helps in forming the bridge of
the nose
 Each posesses : 2 surfaces : External(lateral)
Internal (medial)
4 borders: upper, lower, medial, lateral
 Upper border is short & thickest
 Medial border in its upper part projects backwards as a thin
edge, it has a groove running from above downwards to
lodge anterior ethmoidal nerve
 Lateral surface is smooth & concave covered by the
transverse part of the NASALIS and PROCEROUS muscles.

42.  It is a thin, quadrilateral, flat plate of bone which
forms the postero-inferior parts of the septum of nose.
possesses : 2 surfaces :one on either side
4 borders: superior, inferior,
anterior and posterior
SURFACES: vomer lies in the medial plane as part of the
nasal septum though it is commonly deviated form
mid line; the two surfaces , one on either side, form
medial wall of the corresponding nasal cavity.
 Each surface presents an oblique groove made by the
passage of naso palatine vessels and nerve.

43. BORDERS :
1.Superior border :
expanded: splits into 2
projecting alae; fissure
between the alae articulates
with rostrum of sphenoid
2.Inferior border: articulates
with nasal crest formed by
maxillae and palatine bones
3.Anterior border: its upper
part articulates with
perpendicular plate of
ethmoid bone.
4.Posterior border : free &non
articular

44. 
 Two in number ; curved, thin flat
pieces of bones which lie in the
lateral walls of the nasal cavity .
Each possesses :
2 surfaces : medial & lateral
2 borders : superior& inferior
2 end : anterior & medial
3 processes : lacrimal , ethmoid
maxillary
Posterior end is more tapering &
directed backwards
Superior border is directed
upwards & in its intermediate part
bares 3 processes

45.  In superior border it is again divided into 2 parts anterior part
which articulates with the conchal crest of maxilla, posterior
border articulates with the conchal crest of palatine bones.

46. The palatine bone effectively
completes the posterio-medial
corner of the maxilla on each side ,
contributing to maxilla & the
lateral wall of nose.
Behind , it is supported by the
strong pterygoid plates of the
sphenoid bone.
These are substantial ,since they
form the only origin in the central
middle third for muscle of any
substance

47. This is made up of vomer perpendicular
plate of ethmoid bone & septal cartilage
It does not contribute materially in
resistance to the applied forces since begin
thin , it is flexible & in addition its
articulation in the nasal floor is weak.
The bony component of the septum is
not much stronger, being paper thin.
The lateral nasal wall is made up of the
maxilla , the ethmoid & the perpendicular
plate of the palatine bone , with the minor
contributions from the both inferior
conchae and the nasal bone

48. 1. The naso maxillary & zygomatico
maxillary buttress of the strong bone
forms the vertical pillars in the plane
of the lateral nasal wall at its anterior
& posterior end.
2. The external nasal skeleton is
composed of the pyriform aperuture
of the maxillae, their frontal process
,nasal bones & the upper & lower
cartilages.
3. The tip of the nose is largely
supported by the septal cartilage, the
alar & nasal cartilage.

50.  LATERAL PTERYGOID PLATES : The lateral pterygoid
plate is broad thin and everted , its lateral surface,being
part of the medial wall of the infratemporal fossa , gives
attachment of the lower part of lateral pterygoid ,its medial
surface is the lateral wall of the pterygoid fossa and to it
most of medial pterygoid is attached.

51. The upper part of its anterior border is a
pterygo maxillary fissure;the lower part articulate
with the palatine bone.
Its posterior border is free
 Medial pterygoid plate
The medial pterygoid plate narrower and longer
than the lateral ; its lower end curves into the
lateral , unciform pterygoid hamulus

52.  Pterygoid hamulus deflects the tendon of tensor veli
palatini and pterygomandibular raphe attached to it.
 The lateral surface is the medial wall of the pterygoid fossa
, the TENSOR VELLI PALATINE adjoins it.
 The medial surface is lateral boundary of the posterior
nasal aperture.
 The frontal bone, the body and greater and lesser wings of
the sphenoid are not usually fractured. In fact, they are
protected to a considerable extent by the cushioning effect
achieved as the fracturing force crushes the comparitively
weak bone comprising the middle third of the facial
skeleton.

53. The maxillary sinus is a large
cavity in the maxilla. It is pyramidal
in shape.
The sinus opens middle meatus of
the nose usually by 2 openings one
of which is closed by the mucous
membrane.
The larger bony hiatus of the sinus
is reduced in the bony skull by
following bones
a) From above, uncinate process
of ethmoid bone & desending
process of lacrimal bone
b) From below, by inferior conchae

54.  From behind , by the perpendicular plate of palatine
bones.
 Size is variable . Average measurements are height
3.7cms, width 2.5 cms,anterio posterior depth 3.7 cm
 Maxillary sinus is first to develop at 4th week of intra
uterine life & grows rapidly during 6 to 7 yrs & reaches
full size after the eruption of all the permanent life.

55.  Middle third of the face receives its nerve supply from
the second division of the fifth nerve.
 Branches to the teeth pass through the outer cortex of
the bone.
 The infraorbital nerve innervates the soft tissues of the
lower eye lid, the cheek and the lateral aspect of the
nose and upper lip.
 Palatine branches innervate the mucosa of the palate.
 The nasopalatine nerve passes anteriorly in the
mucosa of the nasal septum bilaterally .

57. • Although there are zones of weakness in the midface , there are pillars
of stronger bone
• These pillers are called buttresses of the face and consist of thicker
bone that transmits the chewing forces to the supporting regions of the
skull.
• These pillers are the pterygomaxillary, Zygomatic, nasomaxillary
• At least the nasomaxillary, pteryomaxillary buttress resist atropy and
osteoporotic changes in older adults to certain degree, where as the
zygomatic buttress can become weak ofter tooth loss.
• The thicker bones facilitate the placement of screws and plates for
internal fixation of fractures.
• Tension developed by muscular pull and the distribution of force by
soft tissues.
• The buttress system of the face can be considered a combination of
pillars that resist compression and trusses that resist tension.

59. APPLIED
SURGICAL
ANATOMY

60. This classification was given by Rowe & william`s :-
I. Fractures not involving the occlusion
1. Central region:-
A. Fractures of the nasal bones and/ nasal septum:-
i. Lateral nasal injuries
ii. Anterior nasal injuries
B. Fractures of the frontal process of maxilla.
C. Fractures of the type a & b which extend into the
ethmoid bone
D. Fractures of the type a , b,& c which extend into
frontal bone (fronto-orbital-nasal dislocation)

61. 2. Lateral region:- Fractures involving the zygomatic
bone, arch 7 maxilla excluding the dento-alveolar
component
a) Dento alveolar fracture
b) Subzygomatic
i. Le fort-I ( low level or Guerin)
ii. Le fort-II (Pyramidal)
3.Supra zygomatic :-
Le fort-III (high level or cranio-facial dysjunction)
These fractures may occur unilaterally or associated
indepedently with a fracture of the zygomatic
complex.

62.  By marciani 1993 (NOE, ZMC)
 Le Fort I – low maxilary fracture
Ia-low maxillary fracture/multiple segment
 LeFort II-pyramidal fractures
IIa-pyramidal & nasal fracture
Iib-pyramidal & NOE fracture
 LeFort III-craniofacial dysjunction
IIIa- +nasal fracture
IIIb- +NOE fracture
 LeFort IV-LeFort II or III fracture & cranial base fracture
IVa- +supraorbital rim fracture
IVb- +anterior cranial fossa & supraorbital rim fracture
IVc - +anterior cranial fossa & orbital wall fracture

64. NASAL SEPTUM
LATERAL PYRIFORM RIM
BELOW THE ZM JUNCTION
PTERYGOMAXILLARY
JUNCTION TO INTERRUPT
PTERYGOID PLATES

65.  EXTRA ORAL SIGNS:-
 Swelling of upper lip
 Increased vertical dimensions of face
 Epistaxsis
 Pain
 INTRA ORAL SIGNS:-
• Buccal sulcus ecchymosis
• Guerin`s sign
• Labial mucosal laciration
• Anterior open bite
• Posterior gagging of occlusion
• Tenderness at nasal aperture
• Tenderness at zygomatic buttress
• Mobility of maxilla
• Dull hallow sound on percussion of teeth

68. AT / BELOW THE
NASOFRONTAL SUTURE
FRONTAL PROCESS OF MAXILLA
LACRIMAL BONES
INFERIOR ORBITAL FLOOR
NEAR INFRA ORBITAL
FORAMEN
ANTERIOR WALL OF
MAXILLARY SINUS
UNDER THE ZYGOMA ACROSS
PTERYGOMAXILLARY FISSURE &
PTERYGOID PLATES

69. 1 .EXTRA ORAL SIGNS:-
• Moon face
• Increased vertical dimensions
• Dish face deformity
• Bilateral circum orbital ecchymosis
• Sub conjunctival hemorrage
• Chemosis
• Increased inter canthal distance
• Epistaxsis
• Patients may have CSF rhinorrhea
• Tenderness + step defect infra
orbital region
• Infra orbital nerve
paresthesia/anesthesia

70. • INTRA ORAL SIGNS:-
• Anterior open bite
• Molar gagging
• Mid palatal split
• Buccal ecchymosis
• Dull sound on percussion of teeth
• Mobility of maxilla at infra orbital level

71. NASOFRONTAL &
NASOMAXILLARY SUTURE
MEDIAL WALL OF ORBIT
THROUGH NASOLACRIMAL
GROOVE & ETHMOID BONES
FLOOR OF THE ORBIT ALONG
INFERIOR ORBITAL FISSURE
LATERAL ORBITAL WALL
THROUGH ZYGOMATICO
FRONTAL JUNCTION &
ZYGOMATIC ARCH

72. • EXTRA ORAL SIGNS :-
• Moon face
• Panda face appearance
• Sub conjunctival hemorrhage
• May have diplopia, restricted eye
movement,enoptholmas
• Increased intercanthal distance
• Depressed nasal bridge
• Epistaxis
• Elongation of face
• Tenderness + step deformity
• Altered papillary level
• Hooding of the eye

73.  INTRA ORAL SIGNS:-
 Anterior open bite
 Molar gagging
 Mid palatal split
 Mobility of maxilla at FZ and nasal bone level

74.  Communition of ethmoid –in Lefort I,& II fracture
leading to dural tear in cribriform plate area resulting
in to CSF leak.—CSF Rhinorrhoea
 Injury to the Infra Orbital nerve and zygomatic nerves
may occur in Zygomatic & lefort II fractures either
unilaterally or bilaterally leading to anesthesia/
paresthesia.
 The anterior, middle and posterior superior alveolar
nerves are frequently damaged.
 Cranial Nerves within the orbit may be involved in
superior orbital fissure syndrome-opthalmoplegia

75.  Globe of the EYE & Optic Nerve are well protected due
to prominence of Zygomatic bone & ring of compact
bone of the optic foramen
 Alteration in the position of globe –Hooding of eye
 Diplopia-fracture of floor of the orbit
 En ophthalmos-fracture of floor of the orbit
 Injury to nasolacrimal duct –epiphora
 Detachment of medial canthal ligament –Traumatic
telecanthus .

76.  In zygomatic complex and lefort I, II, and III fractures, the
maxillary sinuses are involved.
 Bleeding into the cavity and inward herniation of buccal
pad of fat results in one or more opaque on radiological
examination.
 Apart from the routine reduction and repositioning of the
fracture, no special treatment is required in the treatment
of antral wall fractures and the radiological appearance of
the sinuses will clear after about 6 weeks.

77.  Intra oral approach by gingiva buccal sulcas (sub
labial) incision (or) marginal gingival (sulcular)
incision.
 Lower Eyelid Approach.
 Trans conjunctival lateral canthotomy approach.
 Upper Lid Blepharoplasty Approach.
 Brow incision.
 Coronal Approach.
 Weber Ferguson Incision

78.  Midface fractures occur in a wide variety of patterns.
 The various extended access approaches can be
tailored to these fracture patterns.
 Restoration of the facial buttresses is crucial in
reestablishing the pretruamatic aesthetic structure
and function of the facial skeleton.

79.  ROWE AND WILLAMS VOLUME-I
 GRAY`S ANATOMY
 B.D CHAURASIYA `S
 FONCISA – ORAL & MAXILLO FACIAL TRAUMA
SURGERY
 SURGICAL APPROCHES TO FACIAL SKELETON –
EDWARD ELLIS-III
 INDERBER SING- EMBRYOLOGY
.

80.  THANK YOU