Maxillary sinus imaging

Maxillary sinus imaging

1. Maxillary Sinus Imaging

2. CONTENTS

3. INTRODUCTION 1

4. Introduction

5. Maxillary sinus

6. “Maxillary sinus is the pneumatic space that is lodged inside the body of maxilla and that communicates with the environment by way of the middle meatus and nasal vestibule.” 6 Drake, Richard; Vogl , A. Wayne; Mitchell, Adam W. M.  Gray's Anatomy for Students E-Book London: Churchill Livingstone, 2009

7. 7 First described by British surgeon- Sir Nathaniel Highmore in 1651

8. 8 Possible relation between dental pathology and spread of infection to the maxillary antrum was described by Scottish surgeon- Sir John Hunter

9. Development of Maxillary Sinus First paranasal sinus to develop 4th month of fetal life : shallow groove between the oral cavity and the floor of the orbit. At birth : slit like out-pouching of the nasal cavity Develop as an evagination of the mucous membrane of the lateral wall of the nasal cavity at the level of the middle nasal meatus forming a minute space that expands primarily in an inferior direction into the primordium of the maxilla. Grows rapidly by a process known as ‘ Pneumatization ’ during the eruption of deciduous teeth Reaches half its adult size by 3yrs of age Reaches full size after eruption of permanent dentition

10. Development of Maxillary Sinus Courtesy: White SC, Pharaoh MJ. Oral Radiology: principles and Interpretation. 5 th ed.St.Louis (US): Mosby/Elsevier; 2004.p.177-180.

11. Development of Maxillary Sinus

12. Pneumatization Courtesy: White SC, Pharaoh MJ. Oral Radiology: principles and Interpretation. 5 th ed.St.Louis (US): Mosby/Elsevier; 2004.p.177-180. At young age, sinus growth by pneumatization α growth of the maxilla With the advance of age, pneumatization exceeds maxillary growth. Thus the antrum will expand at the expense of the maxillary process.

13. 13 In old age pneumatization becomes more pronounced, the floor of the sinus moves at more downward position particularly when the maxillary teeth are lost.

14. Functions Of The Maxillary Sinus 14

15. 15

16. Out of all the Paranasal sinuses, Maxillary sinus is the most important for an Oral Physician due to its close proximity to the roots of maxillary teeth

17. Normal Anatomy Located within the body of the maxillary bone Pyramidal in shape Apex: directed laterally, is formed by the zygomatic process Base: directed medially, is formed by the lateral wall of nose Floor: formed by the alveolar process of the maxilla

18. Anatomical Relations Mediolaterally Central air-filled cavity Roof : bounded by the orbit Medial wall : bounded by the nasal cavity Lateral wall : related to the zygoma and cheek Anteroposteriorly Anterior wall : related to the facial surface of maxilla Posterior wall : related to the pterygopalatine fossa Floor : related to the apices of the maxillary posterior teeth 18

19. 19

20. Anatomical Relations It communicates with the middle meatus of the nasal cavity in the lower part of the hiatus semilunaris through opening called ostium maxillare It is about 3-6mm in diameter A second opening is usually seen at the posterior end of the hiatus 20

21. Anatomical Relations The internal surface of the maxillary sinus may have bony septa that partially divide it into intercommunicating compartments Separate ostia may be found in relation to these compartments 21

22. Maxillary Sinus Height (opposite first molar tooth)-3.5cm Width -2.5cm Antero-posterior depth- 3.25cm Average volume -15ml 22

23. Blood Supply 23

24. Lymphatic Drainage Lymphatic drainage from the maxillary sinus is relatively poor. Lymphatics from the skin over the anterolateral wall drains to the submandibular nodes. From the antrum it drains into retropharyngeal lymph nodes and then to the upper deep cervical lymph nodes 24

25. Histology of Maxillary Sinus Contains air Lined by mucoperiosteum with a pseudostratified ciliated columnar epithelium 25

26. Histology of Maxillary Sinus Maxillary sinus is lined by three layers: epithelial layer, basal lamina and sub epithelial layer with periostium . Epithelium is pseudo stratified, columnar and ciliated. As cilia beats, the mucous on epithelial surface moves from sinus interior towards nasal cavity. 26

27. Clinical Examination 27

28. Palpation 28

29. Transilllumination 29

30. Intraoral Examination Intraoral examination should be performed looking for the following in upper molar and premolar region:- Alveolar ulceration Expansion Tenderness Paresthesia 30

31. Radiological Investigations 31

32. Radiological Investigations Conventional Intraoral Periapical Occlusal Lateral Occlusal Extraoral Water’s view Standard occipitomental - 0 OM True lateral skull Caldwell view Submentovertex Advanced imaging CT MRI CBCT

33. Periapical Radiograph Radiolucent area above apices of maxillary molars. Floor appears as a thin radiopaque line Septa appear as radiopaque lines within the sinus 33 Area of Antrum shown Base of antral cavity Relationship with maxillary posterior teeth

34. Periapical Radiograph Borders of the maxillary sinus appear as a thin, delicate radiopaque line . (White & Pharoah 2000) In the absence of disease it appears continuous, but on close examination it has small interruptions in its smoothness or density . The roots of maxillary molars usually lie in close apposition to the maxillary sinus and may project into the floor of the sinus, causing small elevations or prominences. 34

35. Relation between maxillary posterior teeth roots and inferior wall of sinus Acc to Sharan et al 0- the root is not in contact with the cortical border of sinus 1- an inferiorly curving sinus floor with the root in contact with the cortical border of sinus 2- an inferiorly curving sinus floor with the root projecting laterally on the sinus cavity but with the root apex outside the sinus boundary 3- an inferiorly curving sinus floor with the root apex projecting into the sinus cavity 4- a superiorly curving sinus floor enveloping part or all of the tooth root 35 Sharan A, Majdar D. Correlation between maxillary sinus floor topography and related root position of posterior teeth using panoramic and cross-sectional computed tomography imaging 2016 3:102 375-381

36. Maxillary Lateral O cclusal 36 Area of Antrum shown Floor Lower half of antral cavity Relationship with upper posterior teeth

37. Panoramic Radiograph 37 1. Floor of Maxillary Sinus 1 2 2. Posterior wall maxillary sinus Area of Antrum shown Floor Posterior wall Base of antral cavity Relationship with upper posterior teeth Medial wall Comparison of both sides

38. Extraoral Landmarks used in Patient Positioning Median plane of the head (Mid Sagittal plane): Vertical plane passing through the mid sagital suture dividing the skull into two half's. Frankfort horizontal line: This line passes from the lower most border of the bony orbit to the upper border of the external acoustic meatus 38

39. Extraoral Landmarks used in Patient Positioning Orbitomental line( Canthomeatal line): Imaginary line from the outer canthus of the eye to the tragus of ear. This is also known as radiographic base line 39

40. Water’s View 40 Area of Antrum shown Antral cavity Roof of the antrum Lateral and medial wall Comparison of internal radiopacities

41. Occipitomental 41 Area of Antrum shown Main antral cavity Lateral Wall Roof or upper border Medial wall Allows comparison of both sides

42. True Lateral Skull 42 Area of Antrum shown Main antral cavity Posterior wall Anterior wall Relation to hard palate and maxillary posterior teeth (Note: Superimposition of one antral shadow on the other)

43. Caldwell View 43 Area of Antrum shown Medial wall Mid portion of the antral roof 1- Frontal sinus 2- Ethmoid sinus 3-Petrous apex 4-Inferior orbital fissure 5-Maxillary sinus obscured by petrous apex *- Site of anterior ethmoidal artery

44. Submentovertex View 44 Area of Antrum shown Lateral and posterior walls Comparison of both sides

45. Systematic approach to examine the Antra Compare antral shadows on both sides- they should be radiolucent Compare the radiodensity of the antrum on each side with the density of the soft tissue shadow lateral to it The antra should be more radiolucent Check the integrity and shape of the roof and lateral walls Also check the medial wall even though it is the least well defined and difficult to interpret 45

46. COMPUTED TOMOGRAPHY 46 A-Frontal sinus B- Ethmoid sinus C- Maxillary sinus D- Nasal septum E- Eye socket Black - Air Gray - soft tissue White - Bone Area of Antrum shown Main antral cavity Floor All walls Roof or upper border Surrounding structures Allows comparison of both sides Hard and soft tissue images

47. COMPUTED TOMOGRAPHY 47 Coronal CT 81- maxillary sinus Axial CT 81- maxillary sinus

48. CBCT 48

49. MRI 49 Coronal T1 weighted MRI Axial T1 and T2 weighted MRI Area of Antrum shown Main antral cavity Floor All walls Roof or upper border Surrounding structures Allows comparison of both sides Hard and soft tissue images

50. Ultrasonography Ultrasound is becoming the diagnostic tool of choice for more and more physicians in detecting sinusitis. Offers fast, reliable and radiation free method or diagnosing sinusitis and has been used successfully in Finland for around 15 years ( Landman 1986) Ultrasound beam sent out by the sinus ultra is reflected from the posterior wall of the sinus when the sinus contains fluid and from the anterior wall when sinus contains air. 50

51. 51 Periapical (paralleling or bisected angle technique) Floor Base of antral cavity Relationship with upper posterior teeth Panoramic Radiograph Floor Posterior wall Base of antral cavity Relationship with upper posterior teeth Medial wall Allows comparison of both sides 0° occipitomental (0° OM) Main antral cavity Lateral wall Roof or upper border Medial wall Allows comparison of both sides

52. 52 Upper Oblique Occlusal Floor Lower half of antral cavity Relationship with upper posterior teeth True lateral skull Main antral cavity Posterior wall Anterior wall

53. 53 Linear or spiral tomography in coronal or sagittal plane Main antral cavity Floor Anterior wall Lateral wall Posterior wall Medial wall Roof or upper border Allows comparison of both sides (coronal only) Computed tomography (CT) or MRI Main antral cavity Floor All walls Roof or upper border Surrounding structures Allows comparison of both sides Images hard and soft tissue

54. Thank You 54

55. Maxillary Sinus Imaging – Session 2

56. Radiology and Radiography Radiology : The science or study of radiation as used in medicine, a branch of medical science that deals with the use of x-rays, radioactive substances, and other forms of radiant energy in the diagnosis and treatment of disease Radiography : The art and science of making radiographs by the exposure of film to x-rays Dental Radiography : The production of radiographs of the teeth and adjacent structures by exposure of film to xrays Haring JI, Howerton LJ. Dental Radiography : Principles and Techniques. 3 rd Ed. Elsevier.

57. Radiology and Radiography Radiology : The branch of medicine concerned with the use of radiation including x-rays and radioactive substances in the diagnosis and treatment of disease. Radiography : The technique of examining the body by directing the x-rays through it to produce images on photographic plates or fluorescen t screens. L.M Harrison. The Pocket medical Dictionary. 1 st ed 1986

58. Radiology and Radiography Radiology : The branch of health sciences dealing with radioactive substances and radiant energy and with diagnosis and treatment of disease by means of both ionizing and non ionizing radiation Radiography : The making of film records of internal structures of th e body by passing x-rays or gamma rays through the body to act on specially sensitized films. Dorlands . The Pocket medical Dictionary. 1 st ed 1995

59. Radiology Radiology : It is the study and use of radiant energy including roentgen rays, radium and radioactive isotopes as applied to medicine and dentistry. Sikri VK. Fundamentals of Dental Radiology. 1 st ed 1992.

60. Maxillary Sinus Lining 60 The lining membrane of paranasal sinuses is a respiratory mucosa – 1mm thick When inflamed – increase in thickness 10-15 times Mucosal membrane thickening greater than 3 mm is most likely pathologic Radiographically – radiopaque band more radiopaque than air filled sinus, paralleling bony wall of sinus

61. Occlusal Radiograph 61 MAXILLARY CROSS SECTIONAL VIEW Area of Antrum shown Antero-inferior aspects of each antrum Relationship with upper posterior teeth

62. Radiography Of Paranasal Sinuses Radiography of paranasal sinuses Posteroanterior projection ( occipito frontal projection of nasal sinuses) 2 methods for obtaining this Posterior Anterior (Granger projection) Modified Method, inclined posterior anterior (Caldwell Projection) Radiography of maxillary sinuses Standard occipitomental projection (0° OM) Modified method (30° OM projection) Bregma Menton PA Waters 62

63. Postero -anterior of the skull (PA skull )/ occipitofrontal (OF) The main clinical indications include: • Fractures of the skull vault • Investigation of the frontal sinuses • Conditions affecting the cranium, particularly: — Paget's disease — multiple myeloma — hyperparathyroidism • Intracranial calcification. 63

64. Posteroanterior (Granger) Projection E xcellent for evaluating the inner and middle ear because the petrous pyramid can be viewed through the orbits. 64

65. Caldwell View 65 Area of Antrum shown Medial wall Mid portion of the antral roof 1- Frontal sinus 2- Ethmoid sinus 3-Petrous apex 4-Inferior orbital fissure 5-Maxillary sinus obscured by petrous apex *- Site of anterior ethmoidal artery

66. Occipitomental 66 Area of Antrum shown Main antral cavity Lateral Wall Roof or upper border Medial wall Allows comparison of both sides Projection taken with patients mouth open for investigation of sphenoidal sinus

67.  Examine the 0° OM using an approach based broadly on that suggested originally by McGregor & Campbell (1950), often referred to as Campbell's lines. 67

68. 68

69. 30° Occipitomental (30° OM) This projection also shows the facial skeleton, but from a different angle from the 0° OM, enabling certain bony displacements to be detected . The main clinical indications include: Detecting the following middle third facial fractures : — LeFortI — Le Fort II — Le Fort III • Coronoid process fractures 69

70. Bregma Menton View This projection used primarily – walls of maxillary sinus- especially in posterior areas, the orbits, the zygomatic arches and the nasal septum Demonstrated medial or lateral deviations of the mandible 70

71. Water’s View 71 Area of Antrum shown Antral cavity Roof of the antrum Lateral and medial wall Comparison of internal radiopacities

72. Maxillary Sinus Septa First mentioned – Underwood in 1910 Formation Bony septa originating in sinus floor – Underwood Septa. Divide the sinus into multiple compartments known as posterior recesses. Location Present in maxillary sinus, act as walls to divide the sinus floor Septa Origin : Classification Underwood – maxillary sinus floor divided into three basins Small anterior one over the premolar region A large median one descending between roots of first and second molars Small posterior one corresponding to third molar region 72

73. Maxillary Sinus Septa Krenmair et al divided septa into primary and secondary. Primary septa corresponding to those first described by Underwood, arising from development of maxilla Secondary septa arising from irregular pneumatisation of the sinus floor following tooth loss Variations with age Other authors classified septa related to the presence/absence of maxillary teeth. Primary septa located superior to maxillary teeth and secondary septa located on edentulous maxillae. 73

74. Diseases of the Maxillary Sinus 74

75. Diseases of the Maxillary Sinus

76. Intrinsic Diseases 76

77. Extrinsic Diseases 77

78. 78

79. Inflammatory Diseases 79

80. Mucositis Thickened mucosa Non corticated band more radiopaque than the air filled sinus, parallelling the bony wall of sinus 80

81. Sinusitis 81 Radiographically there is thickening of sinus mucosa The appearance of thickened mucosa helps to differentiate between an allergic reaction and an infection In case of allergic reaction, the mucosa tends to be more lobulated In case of infection, the mucosal outline is more smoother with the contour following the sinus wall

82. 82 According to Veterans Affairs general medicine clinic study, the accuracy of diagnosing sinusitis increases to more than 80% if the following criteria are considered in the water’s view: 1. Presence of air fluid level 2. Sinus opacity 3. Mucosal thickening greater than 6 mm

83. 83 The resolution of acute sinusitis becomes apparent on radiograph as a gradual increase in the radiolucency of the sinus The thickened mucosa gradually shrinks In time it again becomes radiographically invisible In chronic sinusitis the inflammation may stimulate the sinus periosteum to produce bone resulting in thick sclerotic borders of the maxillary antrum

84. Staging of Sinusitis Kennedy’s Staging 1992, based on history, CT finding and endoscopic appearance Four stages; Stage I, Stage II, Stage III and Stage IV 84 Harvard Staging 1994, similar to Kennedy's Thickening of inflammatory disease 2mm is normal thickness, anything more than 2mm is disease Levine and May Staging 1993, considers involvement of osteomeatal complex Lund-Mackay Staging 1993, most accepted Stage 0: No abnormality Stage 1: Partial Opacification Stage 2 : Total Opacification

85. Retention Pseudocyst 85 Well defined, non corticated, smooth, dome shaped, homogeneous radiopaque mass

86. Retention Pseudocyst Radiographic features Cysts usually found projecting from the floor of the sinus, though some form on the lateral walls Base may be narrow or broad Dodd and Jing – Mucous cysts are more likely to have a broad base, serous more pedunculated Mucous cyst smaller than serous cyst Mucous cyst associated with thickened mucosa 86

87. Polyp Thickened mucous membrane Maxillary sinus shows radiopacity ; which is present despite of the position in which the radiograph is taken. Usually, the radiopacity has convexity pointing upward 87

88. 88 Pseudocyst Odontogenic cysts Dome shaped More rounded or tear drop shaped Lacks corticated border as that of a cyst Floor of antrum is displaced Corticated border of cyst becomes coincident with the bony sinus floor In case of radicular cyst, the lamina dura of involved tooth is not intact Pseudocyst Antral polyps Solitary Often multiple Adjacent mucous membrane lining is not apparent More commonly associated with a thickened mucous membrane Benign neoplasms are usually separated from the sinus cavity by a radiopaque border Malignant neoplasms may destroy the osseous border of the sinus and are less likely to be dome shaped

89. Anthrolith Radiopaque masses having a well defined periphery which may be smooth or irregular in shape Internal density- Homogenous or heteogenous 89

90. Mucocele Radiographically : Uniform radiopacity with a more circular or hydraulic shape Bony expansion with thinning of bony walls Displacement or resorption of teeth Erosion of septa and of bony walls may be seen 90

91. Dental Cysts 91

92. Odontogenic Cysts Radicular cyst, dentigerous cyst, odontogenic keratocyst 92

93. Radicular Cysts Cause elevation of floor of sinus - Appears as a halo 93

94. 94

95. Odontogenic Keratocyst 95

96. Odontogenic Keratocyst 96

97. 97

98. Large Cysts 98 Odontogenic cysts Sinusitis Cyst wall is often thicker and more regular A cyst that occupies the entire sinus causes expansion of medial wall of sinus Loculation - round shape with a cortex, appears more radiolucent than the fluid within the cysts

99. Tumors 99

100. Papilloma 100 Jaiganesh S, Radha S. SINONASAL NEOPLASIA – CLINICOPATHOLOGICAL PROFILE AND IMPORTANCE OF COMPUTED TOMOGRAPHY.JCDR 2015 (6):9

101. Osteoma 101 Borumandi F, Lukas H, Yousefi B, Gaggl A. Maxillary sinus osteoma : From incidental finding to surgical management. J Oral Maxillofac Pathol 2013;17:318

102. Ameloblastoma Ameloblastoma , solid/ multicystic , maxilla; 80-year-old female with painless swelling in vestibule and palate Axial CT image shows scalloped expansive process with destruction of palate and cortical bone defects ( arrow) Coronal CT image, soft-tissue window, shows well-defined soft-tissue mass without cortical outline palatally or buccally ( arrow) 102

103. Squamous Cell Carcinoma 103

104. 104

105. Fibrous Dysplasia Posterior maxilla The normally radiolucent maxilla may be partially or totally replaced by radiopacity of this lesion ‘ground glass’ appearance on extra oral radiographs ‘orange peel’ appearance on intra oral views 105

106. Fibrous Dysplasia Fibrous dysplasia; 23-year-old female with painless swelling of cheek. 3D CT image, of face shows expanded right maxilla and zygoma ( arrow) with elevated orbital floor. Axial CT image shows ground-glass appearance ( arrow). 106

107. Pseudotumour 107

108. Traumatic Injuries 108

109. Traumatic Injuries to Maxillary Sinus Oro Antral Fistula Oroantral fistula is an abnormal communication between the oral cavity and the maxillary sinus . It can result due to several causes such as extraction of teeth, massive trauma, surgery to maxillary sinus, osteomyelitis of maxilla, malignant tumor , infected upper implant denture, Malignant granuloma Radiograph may show break in continuity of floor of maxillary sinus  109

110. Traumatic Injuries to Maxillary Sinus Root Or Foreign Body In The Antrum The inadvertent displacement of a root, even a whole tooth into the maxillary sinus may cause an oro antral fistula Following incomplete extraction of a tooth the apical segment remaining in the socket may be dislodged by injudicious use of elevators into the sinus A root tip in the sinus does not have lamina dura around it. may change its position in the sinus which changes with patient’s head position. It will not change its position when it is trapped between the mucosa and floor of the sinus.  110

111. Traumatic Injuries to Maxillary Sinus Blow Out Fracture Blow to the eye – pressure exerted against orbital walls Pressure of blow forces the inferior periorbital contents (fat and muscle) through the fracture – become entrapped Radiographically – opacification of maxillary sinus with or without fluid level, soft tissue mas sin upper portion of sinus, image of depressed bone fragments In Water’s projection – fractures of the thin walls are imaged as “bright lines” (white) superimposed over sinus 111

112. Traumatic Injuries to Maxillary Sinus Isolated Fractures Isolated fractures of paranasal sinuses involve only a single wall Radiographs –identified by fracture line “bright line” Clouding of involved sinus 112

113. 113

114. 114

115. Role In Forensics It has been reported that maxillary sinuses remain intact, although the skull and other bones may be badly disfigured in victims who are incinerated. Hence maxillary sinuses can be used for identification. Maxillary sinus imaging plays an important role in analysis of maxillary sinus based on its volume, shape and dimensions to determine ethnicity and gender It can assist in giving accurate dimensions for which certain formulae can be applied to determine the gender. 115

116. CONCLUSION 116

117. 117 REFERENCES Whaites E. Essentials of Dental Radiography & radiology. 4 th ed. Spain: Churchill Livingstone;2007. White SC, Pharoah MJ. Oral Radiology Principles and Interpretation. 6 th ed. India: Elsevier;2010. Balaji SM. Textbook of Oral & Maxillofacial Surgery. New Delhi: Elsevier;2009. Chaurasia BD. BD Chaurasia’s Human Anatomy Volume 3. 4 th ed. New Delhi: CBS Publishers & Distributers;2006. Bricker SL, Langlais RP, Miller CS. Oral diagnosis, Oral Medicine and Treatment Planning. 2 nd ed. London: BC Decker Inc;2002 .

118. 118 REFERENCES Karjodkar F. Textbook of Dental & Maxillofacial Radiology. 2 nd ed. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2011 . . Sharan A, Madjar D. Maxillary sinus pneumatization following extractions: A radiographic study. Int J Oral Maxillofac Implants 2008; 23: 48-56. Westesson PL, Larheim TA. Maxillofacial imaging. Germany: Springer; 2006. Fernandes CL. Forensic ethnic identification of crania: the role of the maxillary sinus--a new approach. Am J Forensic Med Pathol .   2004 Dec;25(4):302-13.

119. 119 REFERENCES Haring JI, Howerton LJ. Dental Radiography : Principles and Techniques. 3 rd Ed. Elsevier 2000 RENNIE, C.; HAFFAJEE, M. R. & SATYAPAL, K. S. Shape, septa and scalloping of the maxillary sinus. Int. J. Morphol ., 35(3):970-978, 2017 R Fuhrmann , A Bücker , P Diedrich . (1997) Radiological assessment of artificial bone defects in the floor of the maxillary sinus.. Dentomaxillofacial Radiology 26:2, 112-116. Janner SFM, Caversaccio MD, Dubach P, Sendi P, Buser D, Bornstein MM. Characteristics and dimensions of the Schneiderian membrane: a radiographic analysis using cone beam computed tomography in patients referred for dental implant surgery in the posterior maxilla.
 Clin . Oral Impl . Res .  2011

120. 120 REFERENCES Ohba T, Katayama H. Comparison of panoramic and Waterís projection in the diagnosis of maxillary sinus disease. Oral Surg 1976;42:534-538 Waters CA, Waldron CW. Roentgenology of the accessory nasal sinuses describing a modification of the occipito -frontal position. Halstead CL. Mucosal cysts of the maxillary sinus: report of 75 cases. J Am Dent Assoc 1973;87:1435-1441 Bretschneider JH, de Visscher JG, van der Waal I . Diseases of the maxillary sinus: an overview. Ned Tijdschr Tandheelkd. 2012 Apr;119(4):199-204

121. 121 REFERENCES Kaplan BA, Kountakis SE. Diagnosis and pathology of unilateral maxillary sinus opacification with or without evidence of contralateral disease. Laryngoscope. 2004 Jun;114(6):981-5 . Roque-Torres GD, Ramirez-Sotelo LR, Vaz SL, Bóscolo SM, Bóscolo FN. Association between maxillary sinus pathologies and healthy teeth . Braz J Otorhinolaryngol. 2016 Jan-Feb;82(1): 33-8 An inquiry into the anatomy and pathology of the maxillary sinus. By ARTHUR S. Underwood

122. THANK YOU 122