Maxilla anatomy, development & surgical anatomy

1. DEPARTMENT OF ORAL & MAXILLOFACIAL SURGERY RUNGTA COLLEGE OF DENTAL SCIENCES & RESEARCH KOHKA, BHILAI PRESENTED BY – DR. SHEETAL KAPSE

2. ANATOMY, DEVELOPMENT & SURGICAL ANATOMY OF MAXILLA

3. INCLUSIONS - INTRODUCTION FEATURES OF MAXILLA DEVELOPMENT SURGICAL ANATOMY CONCLUSION RESOURCES

4. INTRODUCTION 2 nd largest bone of face 2 maxillae forms whole of upper jaw Each maxilla contributes in formation of – Face Nose Mouth Orbit Infratemporal fossa Pterygopalatine fossa

5. FEATURES OF MAXILLA Each maxilla has – A body 4 processes – frontal zygomatic alveolar palatine

6. BODY OF MAXILLA Shape – pyramidal It has – Base – directed medially at nasal surface Apex - directed laterally at zygomatic process 4 surfaces – anterior / facial posterior / infratemporal medial / nasal superior / orbital Encloses a cavity – maxillary sinus

7. ANTERIOR / FACIAL SURFACE Directs laterally Incisive fossa -depressor septi Incisivus – alveolar margin Nasalis – superiolateral , along nasal notch

8. Canine fossa – levator anguli oris Infraorbital foramen levator labii superioris Medially – the nasal notch - anterior nasal spine

9. POSTERIOR / INFRATEMPORAL SURFACE Concave Directed – backward & laterally Forms – anterior wall of infratemporal fossa Separated from anterior surface 2-3 alveolar canals for – posterior superior alveolar nerve Posteroinferiorly – maxillary tuberosity & superficial head of medial pterygoid muscle Above maxillary tuberosity -anterior wall of infratemporal fossa, grooved by maxillary nerve

10. SUPERIOR / ORBITAL SURFACE Smooth, triangular & slightly concave Forms – Greater Part Of Floor Of Orbit Anterior border forms – part of inferior orbital margin continues with lacrymal crest of frontal process

11. Posterior border – smooth & rounded Forms most anterior margin of inferior orbital fissure In middle – infraorbital groove Medial border – Anteriorly lacrymal notch, converted into nasolacrymal canal Behind the notch, articulation with - Lacrymal Labrynth of ethmoid Orbital process of palatine bone

12. The superior surface presents – Infraorbital groove & canal Canalis sinosus Inferior oblique muscles

13. THE MEDIAL /NASAL SURFACE Part of lateral wall of nose Posterosuperiorly – maxillary hiatus Above the hiatus – air sinuses Below the hiatus – anterior part of inferior meatus Behind the hiatus – articulates with perpendicular plate of palatine bone & encloses greater & lesser palatine canals

14. THE MEDIAL /NASAL SURFACE Infront of the hiatus – nasolacrymal groove articulates with descending process of lacrymal bone & lacrymal process of inferior nasal concha to forms nasolacrymal canal

15. THE MEDIAL /NASAL SURFACE More anteriorly – conchal creast for articulation with inferior nasal concha . Above the conchal crest – atrium of middle meatus .

16. PROCESSES OF MAXILLA FRONTAL ZYGOMATIC ALVEOLAR PALATINE

17. FRONTAL PROCESS Projects upward & backwards to articulate above – nasal margin of frontal bone infront – nasal bone behind – lacrymal bone Lateral surface – divided by anterior lacrymal crest into anterior smooth & posterior grooved anterior lacrymal crest gives attachment to lacrymal fascia & medial palpebral ligament

18. FRONTAL PROCESS Medial surface – forms lateral wall of nose from above downwards – Uppermost roughened area for articulation with ethmoid Ethmoidal crest – a horizontal ridge, articulates with middle nasal concha Below the ethmoidal crest – atrium of middle meatus conchal crest inferior meatus

19. Pyramidal lateral projection Anterior, posterior & superior surfaces converge here Superiorly – rough, to articulate with zygomatic bone ZYGOMATIC PROCESS

20. Forms half of alveolar arch Bears socket for maxillary teeth In adults = 8 sockets Buccinator arises from posterior part of its outer surface upto 1 st molar tooth. Maxillay torus (occasionally) ALVEOLAR PROCESS

21. Thick horizontal plate Projecting medially Forms largest part of roof & floor Inferior surface – concave & forms anterior 3/4 th of bony hard palate. PALATINE PROCESS

22. Various foramina & pits Posterolaterally – greater & lesser palatine foremen Superior surface –concave from side to side & forms floor of nasal cavity.

23. Medial border – Thicker anteriorly Groove between nasal crest of 2 maxilla receives lower border vomer Anterior part of ridge – incisal crest & anterior nasal spine, Incisive canal Posterior border articulates with horizontal plate of palatine bone Lateral border is continuous with alvolar process

24. ARTICULATIONS OF MAXILLA Superiorly – 3 bones Frontal Nasal Lacrymal Laterally – 1 bone Zygomatic bone

25. ARTICULATIONS OF MAXILLA Medially – 5 bones Ethmoid Inferior nasal concha Vomer Palatine Opposite maxilla

26. AGE CHANGES IN MAXILLA AT BIRTH – Transverse & anterioposterior diameter > vertical diameter Well marked frontal process Body consists of little more than alveolar process Tooth sockets – close to orbit Maxillary sinus is a mere furrow on the lateral wall of nose IN ADULTS – Vertical Diameter Is More due to – Developed alveolar process Increased size of maxillary sinus IN OLD – Infantile condition Resorption of alveolar bone

27. DEVELOPMENT OF MAXILLA MAXILLA develops from ossification in mesenchyme of maxillary process of 1 st arch. No arch cartilage / primary cartilage Center of ossification – close to the cartilage of nasal capsule Center of ossification – in angle between division of infraorbital nerve From this center the bone formation spreads – Bony trough for infraorbital canal is formed . Posteriorly – below the orbit toward the developing maxilla Anteriorly – toward the future incisor region Superiorly – to form frontal process Medially – to form palate

28. From this trough a downward extension of bone forms the lateral alveolar plate. Medial alveolar plate – from junction of palatal process & main body of forming maxilla. These plates forms a trough of bone around the maxillary tooth germ. There is contribution of secondary cartilage. Zygomatic / malar cartilage adds in development of maxilla.

29. According to B.D. Chaurassia’s human anatomy 4 th edition vol. 3 The Head & Neck MAXILLA ossifies from 3 centers in the membrane – 1 center for maxilla proper – 6 th week of IUL, above the canine fossa 2 centers for premaxilla Of 2 premaxillary centers- Main center above the incisive fossa - 7 th week of IUL Second center – ventral margin of nasal septum - 10 th week of IUL soon fuses with palatal process of maxilla. Premaxilla begin to fuse with alveolar process almost immediately after the ossification begins.

30. SURGICAL ANATOMY OF MAXILLA

31. Normal Anatomy Face ( midface ) is the region from supraorbital rims to maxillary alveolar process

32. Major structures are labeled in the picture. Nasofrontal suture Zygomaticofrontal suture Zygomaticotemporal suture SOF = Superior orbital fissure IOF = Inferior orbital fissure Orbital ‘rim’ 3D CT Anterior View

33. Nasofrontal suture Zygomaticofrontal suture Zygomaticotemporal suture 3D CT Left Lateral View

34. Axial view Key structures A = Frontal sinus, anterior wall B = Frontal sinus, posterior wall *Note: The right frontal sinus is not pneumatized in this case. Posterior wall of frontal sinus fracture may coexist with brain injury

35. • Do not confuse the suture between nasal bone and frontal process of maxilla for a fracture • Look for a piece of fracture in the optic foramen, it is the true emergency of facial fracture Key structures D = Orbit, medial wall E = Orbit, lateral wall F = Suture between sphenoid and zygomatic bones  = Nasomaxillary suture 1 = Globe 2 = Ethmoid sinus 3 = Sphenoid sinus 4 = Nasal bone 5 = Maxilla, frontal process 6 = Orbit, lateral rim 7 = Sphenoid bone 8 = Optic foramen  Axial view

36. Clear maxillary sinuses can almost rules out certain fractures such as ZMC, LeFort , blowout fractures Key structures F = Groove for infraorbital nerve G = Maxillary sinus, posterolateral wall 5 = Maxilla, frontal process 9 = Maxillary sinus 10 = Zygomatic arch 11 = Pterygoid bone 12 = Nasolacrimal duct 13 = Mandible, condyle Axial view

37. Key structures H = Maxillary sinus, anterior wall I = Maxillary sinus, medial wall J = Medial pterygoid plate K = Lateral pterygoid plate 9 = Maxillary sinus 14 = Mandible, ramus Fracture of the pterygoid plates may represent LeFort fracture Axial view

38. Lucency in midline of the maxilla is a normal finding seen occasionally Key structures J = Medial pterygoid plate K = Lateral pterygoid plate L = Maxilla, spine 14 = Mandible, ramus 15 = Maxilla bone/ hard palate Axial view

39. Coronal section • Remind yourself that CT can miss subtle tooth fracture, although with the coronal and sagittal reformation. Obtain orthopanthogram or dedicated tooth film when in doubt Key structures L = Maxilla, spine * = Nasomaxillary suture 4 = Nasal bone 5 = Maxilla, frontal process

40. Key structures D = Orbit, medial wall M = Nasal septum 5 = Maxilla, frontal process 15 = Maxilla bone/ hard palate 16 = Frontal sinus 17 = Mandible, body Coronal section

41. Key structures M = Nasal septum N = Ethmoid bone, perpendicular plate O = Orbit, roof P = Orbit, floor Q = Maxillary sinus, posterolateral wall **= Zygomaticofrontal suture 1 = Globe 2 = Ethmoid sinus 6 = Orbit, lateral rim Coronal section

42. Key structures J = Medial pterygoid plate K = Lateral pterygoid plate N = Ethmoid , perpendicular plate 3 = Sphenoid sinus 10 = Zygomatic arch 14 = Mandible, ramus 18 = Mandible, angle Coronal section

43. Key structures P = Orbit, floor 7 = Pterygoid bone 9 = Maxillary sinus 15 = Maxilla bone /hard Palate • Orbital blowout fracture is best seen in sagittal and coronal images • Facial CT is not completed without image reconstruction Sagittal section

44. Key structures 3 = Sphenoid sinus 4 = Nasal bone 15 = Maxilla bone/ hard palate Mid saggital section

45. WATER’S VIEW The most comprehensive single projection display Excellent view of Maxilla Maxillary sinuses Zygoma Zygomatic arches Rims of orbits, esp. floor Nasal bones

46. WATER’S VIEW Rule: smooth, nondisrupted , same contour on both sides Key structures 1 = Frontal sinus 2 = Maxillary sinus 3 = Frontal process of Zygoma 4 = Body of Zygoma ( malar eminence) 5 = Temporal process of Zygoma Dotted line = zygomaticofrontal suture Dolan’s lines of reference Line A, B, C

47. Line A Begins at inner surface of Zygomaticofrontal suture, follows orbital surface of zygoma , maxilla, frontal process of maxilla and arch of nasal bone If drawn to both sides, the line is similar to lazy ‘W’ or half frame of reading glasses Line B Begins at lateral and inferior margin of maxilla and extends along lateral wall of maxillary sinus and inferior surface of zygomatic Arch Ends at glenoid fossa

48. Line C Begins at lateral and inferior margins of maxilla, extends along lateral wall of maxillary sinus and inferior surface of zygomatic arch Ends at glenoid fossa “Friendly Line” Medial half of Line C is the anterolateral wall of the maxillary sinus. If it is disrupted, the possibilities of fracture include 1) Isolated maxillary antrum 2) Zygomaticomaxillary complex (ZMC) 3) LeFort

49. Mc Grigor’s /Campbell’s line

50. Caldwell’s View Excellent view of Entire rim of orbit, esp. superomedial rim Ethmoid sinus Floor of orbit may be well seen in petrous bones are projected below the inferior orbital rim (not in this example)

51. Key structures 1 = Ethmoid sinuses 2 = Orbit Line A , B , C , D = superior, lateral, inferior and medial walls of the orbit, respectively Line E = midline nasal septum and vomer Rule: Ethmoid sinuses density should be equal, darker than orbit Smooth nondisrupted orbital walls 2

52. Lateral cephalogram Excellent view of Frontal sinus : anterior wall Maxillary sinus: anterior and posterior wall Sphenoid sinus Pterygoid plate, hard palate Floor of anterior cranial fossa,

53. Key structures 1 = Frontal sinus 2 = Maxillary sinus 3 = Sphenoid sinus 4 = Hard palate 5 = Anterior wall of temporal fossa Between green arrows = Pterygoid plate Line A = Anterior wall of frontal sinus Line B = Anterior cranial fossa Line C = Anterior wall of maxillary sinus Line D = Posterior wall of maxillary sinus

54. TOWN’S VIEW Key structures 1 = Zygomatic arch Line A = Posterolateral wall of maxillary sinus Rule: Smooth, nondisrupted line Excellent view of Maxillary sinus: posterolateral wall Zygomatic arch

55. Hot Sites

56. Maxillary Fractures  Types of maxillary fractures -  Maxillary sagittal fracture (maxillary sinus fracture)  Palate fracture  Alveolar process fracture  LeFort fractures  LeFort I fracture  LeFort II fracture  LeFort III fracture  Combination (bilateral, hemi-)

57. Maxillary sagittal fracture  Maxillary sinus fracture  Fracture of a maxilla in sagittal plane, involving anterior-lateral wall of a maxillary sinus ( LeFort fractures represent bilateral maxillary fractures)  Due to direct blow to either right or left midface  Plain film shows opacified maxillary sinus, however it is usually inadequate for diagnosis

58. 68-year-old man was found down. There is a sagittal plane fracture of the left maxillary sinus (red arrow) with hemosinus (H)

59. Isolated alveolar process fracture Fracture of any portion of the alveolar process Clinically evident by malalignment and displacement of teeth contained within fractured segment Even on CT, fracture may be subtle and easily overlooked Further imaging may be needed when the diagnosis is made X-ray of the teeth or a panoramic view (look for dental injuries) Chest radiograph (look for aspirated teeth)

60. Middle age women fell onto her mouth. Red arrows show the comminuted fractures of the maxillary alveolar process on the right side. These fractures are considered ‘open’ as they are connected to the oral cavity.

61. LeFort Fractures Among the most severe fractures seen in face and associated with high-energy trauma Named after René LeFort , a French physician, who studied facial fractures in cadavers. Result was published in 1901  Key facts - In each type, there is a partial or complete separation of maxilla from the remainder of the facial skeleton All LeFort fractures must extend through posterior face, transects the pterygoid processes Any combination of LeFort I, II, and III patterns can occur

62. LeFort I fracture  Definition: transmaxillary fracture  Transverse (horizontal) fracture of inferior maxillae, involving maxillary sinuses (all except superior walls), lateral margin of nasal fossa, nasal septum and pterygoid plates  Clinical: free floating and movable hard palate with maxillary teeth  Imaging findings  Opacified bilateral maxillary sinuses  Transverse fracture through the inferior maxillae above hard palate  Best shown and confirmed by coronal and sagittal reformatted CT images

63. 48-year-old man was kicked by a horse. LeFort I fracture line along bilateral maxillary sinuses (red arrows). Pterygoid plate fractures are not shown H = Hemosinus , Blue arrow = Mandibular fracture

64. LeFort II fracture Pyramid-shaped maxillary fracture, involving maxillary sinuses (anterior-lateral walls), inferior orbital rim, orbital floor and nasofrontal suture Clinical: free floating, movable midface including maxillary teeth, hard palate and nose  Imaging findings:  Opacified bilateral maxillary sinuses and orbital emphysema  Fractures of anterior/lateral walls of maxillary sinuses, inferior orbital rims/floors and disruption of nasofrontal suture  Best seen and confirmed by coronal reformatted CT images

65. Middle age man in motor vehicle accident. Fracture lines are demonstrated in red arrows. Fracture of pterygoid plates are present in all type of LeFort fractures. H = Hemosinus

66. LeFort III fracture  Craniofacial disjunction This fracture separates calvaria (skull) from the facial bones. Most severe of all LeFort fractures  Definition: separation of facial bones from the skull  Zygomas separated from sphenoid at zygomatico -sphenoid sutures  Nasal bones and medial orbital walls separated from frontal bone at nasofrontal sutures Best seen in coronal images Clinical: movement of face relative to the skull  Imaging findings:  Plain film will underestimate degree of injury to severe soft tissue swelling obscuring the bony details. CT is recommended due

67. 32-year-old man, unrestrained driver in a motor vehicle accident. Blue arrows define LeFort II fracture. Red arrows define the LeFort III fracture.

68. malar fractures- Trauma to infraorbital margin may cause sensory loss of infraorbital skin. Sometimes injury to nasolacrymal duct – epiphora .

69. Imaging Approach - Plain Film  Friendly line ( anterolateral antral wall of maxillary sinus)  Both intact  NO ZMC or LeFort fractures  Blowout fracture  Isolated fractures of lateral orbital wall, zygomatic arch  One disrupted  ZMC fractures  Maxillary sagittal fracture (isolated sinus fracture)  Both disrupted  LeFort fractures

70.  Clear sinus sign (= all sinuses and mastoid are clear of fluid), there are three possible facial fractures:  Nasal bone fractures  Isolated zygomatic arch fractures  Mandible fractures  Bloody sinuses  Pterygoid plate fracture present - probable LeFort fracture  Maxillary wall fractures  Orbital floors, NOE region fractures  ZMC fractures  With fracture of lateral margin of nasal fossa = LeFort I  With fracture of inferior orbital rim = LeFort II  With fracture of zygomatic arch = LeFort III

71. TRAJECTORIES OF MAXILLA According to Bennignhoff – Vertical trajectories Frontonassal buttress Malarzgomatic buttress Pterygoid buttress horizontal trajectories Hard palate Orbital margin Zygomatic arches Palatal bone Lesser wing of sphenoid

72. Maxilla is spongy bone & houses paranasal sinuses - absorbs the energy of blunt trauma Articulation with frontal process & zygoma – stability. Porous – ample blood supply – prevents spread of infection. Boney defect > 5 mm = grafting.

73. SINUS LIFT PROCEDURE

74. ECTOPIC INFRAORBITAL NERVE IN A MAXILLARY SINUS SEPTUM: ANOTHER POTENTIALLY DANGEROUS VARIANT FOR SINUS SURGERY P. Mailleux1, O. Desgain2, M.I. Ingabire1 Evidence in Health and Social Care (Online journal) www.rbrs.org/dbfiles/journalarticle_0814.pdf World Neurosurg . 2011 Sep-Oct;7 2010, 93: 308-309 ; discussion 266-7

75. POSITION OF INFRAORBITAL FORAMEN Sárka Bejdová a,*, Václav Krajícek b, Miroslav Peterka a,c , Pavel Trefný a,d , Jana Velemínská a Variability in palatal shape and size in patients with bilateral complete cleft lip and palate assessed using dense surface model construction and 3D geometric Morphometrics , Journal of Cranio - Maxillo -Facial Surgery 40 (2012) 201e208 Skulls 196 sides

76. Majority – Oval in male skull (54.7%) & on left side (52.8%) Round on right side (34) & oval in left side (23) Directed inferomedially – 65.8 % in males - 67.8 % in females Present in vertical line with 1 st premolar = 70/196 sides no gender predilection Mean distance between infraorbital margine & infraorbital foramen = 7.39 ±1.63 mm 4/ 100 skulls – accessory foramina 1 accessory foramina – 2 male & 1 female 2 accessory foramina – 1 male skull mostly on left side & oval in shape.

77. Variability in palatal shape and size in patients with bilateral complete cleft lip and palate Sárka Bejdová a,*, Václav Krajícek , Miroslav Peterka , Pavel Trefný ,Jana Velemínská ; Variability in palatal shape and size in patients with bilateral complete cleft lip and palate assessed using dense surface model construction and 3D geometric morphometrics ; Journal of Cranio - Maxillo -Facial Surgery 40 (2012) 201e208.

78. Flatter & narrower in bilateral cleft lip & palate cases. Most notable size difference is in area in between maxilla & maxilla, even premaxilla can remain separate from rest of the palate. Mean Palatal configuration of premaxilla & adjacent palatal area in lateral projection is – concave in normal individuals clefted in bilateral cleft lip & palate cases Palate of clefted patient is more conical anteriorly than posteriorly.

79. Anatomical variation and morphology in the position of the palatine foramina in adult Maria Piagkou , Theodore Xanthos , Sophia Anagnostopoulou , Theano Demesticha , Evangelos Kotsiomitis, Giannoulis Piagkos, Vassilis Protogerou , Dimitrios Lappas , Panayiotis Skandalakis , Elizabeth O. Johnson ; Anatomical variation and morphology in the position of the palatine foramina in adult human skulls from Greece; Journal of Cranio - Maxillo -Facial Surgery 40 (2012) e206ee210

80. The study was conducted on 71, Greek dry, adult human skulls of the twentieth century available in the Anatomical Museum of the Department of Anatomy, Faculty of Medicine, Athenian University. The investigated normal skulls with fully erupted 3rd maxillary molars were evaluated to describe the intraoral landmarks of the GPF and related structures.

81. High tuberosity block – for maxillary anesthesia. Control hemorrhage in cases of repair of nasal septum ( septorhinoplasty ). Greater palatine artery can damage in fracture of – Medial wall of maxillary sinus Lateral wall of maxillary sinus Pterygomaxillary dysjunction Downfracturing of maxilla Greater palatine foramen is also important in closure of oroantral communication with palatal flap.

82. Mean distance of greater & lesser palatine foramina from midsagittal suture greater palatine foramina = 1.53 cm lesser palatine foramina = 1.46 ± 0.22 cm ( rt ), 1.47 ± 0.17 cm ( lt )

83. Mean distance of greater palatine foramina from posterior border of maxilla Rt side = 0.46 ± 0.10 cm Lt side = 0.47 ± 0.11 cm

84. Mean distance of greater & lesser palatine foramina from alveolar ridge Rt side = 0.31 ± 0.17 cm Lt side = 0.29 ± 0.16 cm Avarage = 0.3 cm Rt side = 0.41 ± 0.19 cm Lt side = 0.38 ± 0.02 cm

85. Diameter - Average anteroposterior diameter = Average transverse diameter = Position of greater palatine foramen 76.2% cases = between proximal distal surface of maxillary 3 rd molars Position of lesser palatine foramen 71.9 % cases = at the junction of palatine bone & inner lamella of pterygoid plate Rt side = 0.53 ± 0.09 cm Lt side = 0.54 ± 0.09 cm Lt side = 0.27 ± 0.05 cm Rt side = 0.26 ± 0.06 cm

86. Number of lesser palatine foramen– 53.45 % cases = 1 31% cases = 2 (bilaterally) 2.1 % cases = 5 (rare)

87. CONGENITAL DEFECTS Macrostomia Microstomia

88. Oblique cleft lip Bilateral cleft lip cleft lip & cleft palate

89. SYNDROME ASSOCIATED

90. ROMBERG / PARRY ROMBERG SYNDROME – progressive hemifacial atrophy

91. CROUZON SYNDROME/ CRANIFACIAL DYSOSTEOSIS – midface hypoplasia , underdeveloped maxilla

92. APERT SYNDROME/ ACROCEPHALOSYNDUCTYLY – middle third of face is markedly retruded

93. Marfan syndrome

94. DYCROCYSTORHINOSTOMY

95. Some important structures related to posterior wall of maxilla

96. MAXILLOFACIAL TRAUMA

97. MECHANISM OF INJURY Middle third of face is a complex of bones & cartilages organized in a system of buttresses. In adults it is extensively pneumatized. The maxilla a box like bone has been harder to assess as an entity; NAHUM (1975) tested the thin anterior wall of maxilla & found that this shattered at quite low force loadings in the range 150-300 lbs (0.67-1.34kN). 208- 475 lb for zygoma > 75 lb for nasal bone

98. STANLEY & NOWARK (1985) did cephalometric study about the cadaver facial impacts where they stresses on importance of angle of impact in relation to the horizontal buttress of the facial skeleton. Impact on the nasion at 30-60 o above the horizontal = Le Fort III fracture (craniofacial disjunction)

99. Horizontal impacts along the Frankfort plane = Le Fort II fracture pyramidal fracture

100. 3. Direct horizontal or angular blow at the level of upper teeth but below the anterior nasal spine = Le Fort I or horizontal maxillary fracture.

101. Riu et al 1960 Blanton & Biggs 1969 proposed that – when force is transmitted from below the honeycomb ( Blanton & Biggs ) pyramidal ( Riu et al ) configuration of paranasal sinuses , with maxillary sinus forming the base & sphenoid sinus forming the apex, forms an architectural structure that is particularly well suited to a protective energy absorbing role.

102. GEOMATRIC CONCEPT OF THE CRANIOFACIAL SKELETON These models represents simplified interpretations of the complex anatomy of the bony structural pillars that transmits the forces of mastication, devised to further understanding of fracture patterns .

103. Rowe & Killey (1955) emphasized the mechanical strength of 3 paired girders in transmission of force evenly to the skull base – Alveoli & transpalatal arch Palatine-pterygoid buttress posteriorly Zygomaic complex laterally Additionl support in the central buttress of vomer & ethmoid vertical plate The arched palate & infraorbital rim join the anterior & lateral girders.

104. In a functional analysis of the facial skeleton Sicher & Du Brul 1975 considered that the facial structures are anchored to the skull base by 3 pairs of curved vertical pillars – Canine pillar Zygomatic pillar Pterygoid pillar These authors gave greater importance to the horizontal pillars connecting the curved vertical pillars, specially the supraorbital bar.

105. Sturla et al 1980 performed cadaver impaction studies & proposed a lattice shaped structure of facial skeleton. They emphasized on the importance of vertical pillars & transverse plateforms – the hard palate below & frontal sphenoid bone above.

106. Manson et al 1983 and Gruss & Mackinnon 1986 advised that anterior vertical buttress are reconstituted to preserve the facial height, in case of trauma.

107. Gentry et al 1983 studied the thin axial section CT scan of cadaver & identified 3 horizontal sturts Superior Middle / orbital Inferior / palatal

108. 3 sagittal sturts – Median / septal Parasagittal Lateral

109. 2 paired posterior coronal sturts – Posterior maxillary pterygoid

110. IMPORTANCE OF OHNGREN’S PLANE

111. MAXILLARY OSTEOTOMY History - 1859 Langenbeck 1921 Cohn Stock

112. Osteotomy Segmental maxillary osteotomies Single tooth osteotomy Corticitomies Anterior segmental osteotomy Posterior segmental osteotomy Horse shoe osteotomy

113. Total maxillary osteotomies Le Fort I osteotomy Le Fort II osteotomy Le Fort III osteotomy

114. Le Fort I osteotomy

115. Vascular structures

116. Seibert (1997) – palatal contribution to blood supply of mobilized Le Fort I segment , which is mainly by – Ascending palatine branch of facial artery Ascending pharyngeal branch of external carotid artery.

117. Le Fort II osteotomy

118. Le Fort III osteotomy

119. Segmental maxillary osteotomy

120. Anterior segmental osteotomy

121. Posterior segmental osteotomy

122. SAME (surgically assisted maxillary expansion)

123. External Sinus Surgery Andrew H. Murr , MD JOURNAL OF AMERICAN RHINOLOGY SOCIETY Revised 6/2011 care.american-rhinologic.org/ external _ sinus _ surgery

124. Caldwell-Luc Approach George Caldwell (1893); New York & Henri Luc (1897); Paris

125. PNEUMATIZATION OF MAXILLARY SINUS Increase pneumatization – thinning of walls Mattila & Westerholm 1968- continuation of widening of sinus after dental extraction. Young v/s adult maxillary sinus Killey & Kay 1972 – 9/362 oroantral communication in 0-15 years of age group.

126. RESOURCES TEXT BOOK – B.D. Chaurassia’s human anatomy 4 th edition vol. 3 The Head & Neck. Gray’s Anatomy 39 th edition. Ten Cate’s Oral Histology, 6 th edition. The Head & Neck by- Hennry Hollinshed Killey’s fracture of middle third of facial skeleton Orthognathic Surgery By – George Dimitroulis , M. Franklin Dolwick , Joseph E. Van Sickels . Craniomaxillofacial trauma by – D.J. David, D.A. Simpson. Oral & maxillofacial surgery fonseca vol. 2 by – Betts & Turvey . The Maxillary Sinus & Its Dental Implications by – Killey & Kay.

127. RESOURCES OTHER SOURCES - Reoperative midface trauma.Yang RS, Salama AR, Caccamese JF. Oral Maxillofac Surg Clin North Am. 2011 Feb;23(1):31-45, v. Epub 2010 Dec 3. Gruss JS, Phillips JH. Complex facial trauma: the evolving role of rigid fixation and immediate bone graft reconstruction. Clin Plast Surg. 1989 Jan;16(1):93-104 Evidence in Health and Social Care, World Neurosurg . 2011 Sep-Oct;7 2010, 93: 308-309 ; discussion 266-7 P. Mailleux , O. Desgain , M.I. Ingabire;Ectopic infraorbital nerve in a maxillary sinus septum:another potentially dangerous variant for sinus surgery Maria Piagkou , Theodore Xanthos , Sophia Anagnostopoulou , Theano Demesticha , Evangelos Kotsiomitis, Giannoulis Piagkos, Vassilis Protogerou , Dimitrios Lappas , Panayiotis Skandalakis , Elizabeth O. Johnson ; Anatomical variation and morphology in the position of the palatine foramina in adult human skulls from Greece; Journal of Cranio - Maxillo -Facial Surgery 40 (2012) e206ee210 Sárka Bejdová a,*, Václav Krajícek , Miroslav Peterka , Pavel Trefný ,Jana Velemínská ; Variability in palatal shape and size in patients with bilateral complete cleft lip and palate assessed using dense surface model construction and 3D geometric morphometrics ; Journal of Cranio - Maxillo -Facial Surgery 40 (2012) 201e208.

128. THANK YOU

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