Maxillomandibular defects and treatment.pptx

includes general guidelines for rehabilitating maxillomandibular defects including classification and treatment planning

1. Maxillomandibular defects Dr Avneesh Saxena 2 nd year resident Guided by Dr Deeksha Gupta 1

2. Table of content Introduction Anatomy of maxilla Classification of maxillary and mandibular defects Maxillary defect treatment part 1 Mandibular defects 2

3. Maxillofacial Prosthetics - The art and science of anatomic, functional, or cosmetic reconstruction by means of nonliving substitutes of those regions in the maxilla, mandible, and face that are missing or defective because of surgical intervention, trauma, pathology, or developmental or congenital malformations. Maxillofacial prosthetics is the branch of prosthodontics concerned with the restoration and/ or replacement of stomatognathic and craniofacial structures with prostheses that may or may not be removed on a regular or elective basis. -GPT 9. 3

4. Anatomy • Roof - Floor of the orbit. • Lateral walls - Lateral walls of the maxillary sinuses zygomatic bone • Central portion - Maxillary sinus. • Anteriorly, it comprises the midface supporting the nose and anterior teeth. Overlying the posterior pterygoid region of the maxilla is the cranial base. 4

5. 5

6. Congenital Defects:- These defects most commonly occur because of two main reasons, when the mother during pregnancy is practicing pernicious habits like smoking, alcoholism and drug abuse or during the developmental phase of the fetus some obstruction hampers the normal development of tissues. 6

7. most accepted classifications of maxillary and mandibular clefts Davis and Ritchie (1922) classified the congenital clefts and divided it into three groups according to the position of the cleft in relation to the alveolar process: Group I:- prealveolar clefts, unilateral, median, or bilateral. Group II:- postalveolar clefts involving the soft palate only, the soft and hard palate or a submucous cleft. Group III:- alveolar clefts, unilateral, bilateral, or median 7

8. Spina (1974) gave the classification as follows:- Group I:-. Pre-incisive foramen clefts (clefts lying anterior to the incisive foramen). Clefts of the lip with or without an alveolar cleft- a. Unilateral b. Bilateral c. Median Group II:- Transincisive foramen clefts (clefts of the lip, alveolus, and palate)- a. Unilateral. b. Bilateral. Group III:- Postincisive foramen clefts. Group IV:- Rare facial clefts. 8

9. Veau’s Classification (1931):- The Veau classification system divides the cleft lip and palate into 4 groups, which are Group I:- Defects of the soft palate only (A). Group II:- Defects involving the hard palate and soft palate (B). Group III:- Defects involving the soft palate to the alveolus, usually involving the lip (C). Group IV:- Complete bilateral clefts (D). 9

10. Modified Kernahan and Stark Classification (1971):- 10

11. Acquired defects Surgery is first choice for early cancers and for cancers that do not respond to radiation and chemotherapy in the form of salvage. Unfortunately surgery can result in cosmetic, functional and psychological impairment greatly affecting the patient‟s quality of life. Such kind of ablative surgeries gives rise to a wide range of maxillofacial defects; such defects are called as acquired defects of the maxillofacial region 11

12. Acquired palatal defects  Lack of continuity of originally intact palatal structures through the whole or part of its length. Etiology Surgical e.g. tumor removal. Traumatic fracture of maxilla. Pathological conditions e.g. osteomyelitis, T. B., and syphilis and mucormycosis 12

13. Classification of maxillectomy defects Ohngren's classification system for maxillectomy defects in 1933 13

14. 14

15. In its early stages, cancer originating in the anteroinferior quadrant may irritate the middle or anterior branch of the superior alveolar nerve and elicit pain in the incisors, canines, and premolare . Later, the tumor causes bulging of the cheek, gingivolabial fold, or hard palate. Anterosuperior quadrant includes the infraorbital canal and the anterior roof of the sinus. Cancer in this quadrant produces numbness over the upper lip or cheek and pain or numbness in the incisors and canines 15

16. Molar teeth may become loose or painful when cancer originates in the posteroinferior quadrant Posterosuperior quadrant, the infraorbital canal may be separated from the sinus cavity by a layer of relatively thick bone. Cancer originating at this site usually remains asymptomatic until infraorbital symptoms and bloody nasal discharge reveal far-advanced disease. 16

17. Lederman’s classification 2 horizontal lines pass through floor of orbit and maxillary sinus producing supra structure :ethmoid sphenoid, frontal sinus, olfactory area of nose Mesostructure : maxillary sinus and respiratory part of nose Infrastructure: alveolar processes 17

18. Aramany’s Classification for Maxillectomy Defects :- categories based on the relationship of the defect with the abutment teeth . Class 1:- Resection is performed in the anterior midline of the maxilla, with abutment teeth present on one side of the arch. Class 2:- The defect is unilateral, retaining the teeth on the contralateral side. Class 3:- Defect occurs in the central portion of the hard palate and may involve part of the soft palate. Class 4:- Defect crosses the midline and involves both sides of the maxilla, with abutment teeth present on one side. Class 5:- Defect is bilateral and lies posterior to abutment teeth. Class 6:- Anterior maxillary defect with abutment teeth present posterior to the defect on either sides of the remaining maxilla. 18

19. 19

20. Spiro’s Classification of Maxillary Defects- Spiro et al reviewed 403 maxillectomies performed between 1983 and 1993. They suggested the following classification 1. Limited Maxillectomy- Any maxillectomy in which one wall of the maxillary antrum is removed. 2. Subtotal Maxillectomy- Maxillectomy in which at least two walls of the antrum are removed including the palatal wall. 3. Total Maxillectomy- Complete resection of the maxilla 20

21. Liverpool Classification of Maxillectomy Defects:- Vertical Component- Class 1:- Maxillectomy not causing oro -nasal fistula. Class 2:- Maxillectomy not involving the orbit. Class 3:- Maxillectomy involving the orbital adnexae with orbital retention. Class 4:- Maxillectomy with orbital enucleation or exenteration. Class 5:- Orbitomaxillary defect. Class 6:- Nasomaxillary defect. Horizontal Component- Letter a:- Palatal defect only. Letter b:- Less than or equal to half of the bilateral maxilla. Letter c:- Less than or equal to half of unilateral maxilla. Letter d-:-Greater than half of the maxillectomy. 21

22. 22

23. Cordeiro’s Classification of Maxillary Defects Type 1:- Limited maxillectomy, one or two walls of maxilla resected with preservation of palate. Type 2:- Sub-total maxillectomy, 5 out of 6 walls of maxilla are resected preserving the orbital floor. Type 3:- Total maxillectomy, resection of all 6 walls of maxilla. This type is further divided into two parts Type 3a:- Total maxillectomy with orbital contents preserved Type 3b:- Total maxillectomy with orbital exenteration. Type 4:- Orbito-maxillectomy, orbital exenteration with resection of 5 walls of maxilla, preserving the palate 23

24. 24

25. Reconstruction Algorithm:- Type 1 Defect:- Reconstruction with free non vascularized bone may be required to replace bone in critical area. Further obliteration can be done by using Radial Forearm Faciocutaneous Flap (RFFF). Type 2 Defect:- RFFF can be used to reconstruct missing palate. An osseo - facio -cutaneous RFFF can be used to reconstruct anterior maxilla, which will also provide good lip support. Type 3a Defect:- Free non vascularized bone can be used to reconstruct the orbital floor and the remaining defect can be closed by using rectus abdominus or temporalis flap. Type 3b Defect:- Reconstruction can be done by using rectus abdominus flap with skin paddles to reconstruct palate, nasal wall or facial skin. Type 4 Defect:- Reconstruction can be done by using rectus abdominus flap with or without skin paddles. 25

26. Cantor and Curtis Classification of Mandibular Defects Class I:- Radical alveolectomy with preservation of mandibular continuity. Class II:- Lateral resection of the mandible distal to the cuspid area. Class III:- Lateral resection of the mandible to the midline. Class IV:- Lateral bone graft and surgical reconstruction. Class V:- Anterior bone graft and surgical reconstruction. Class VI:- Anterior mandibular resection without surgical reconstruction 26

27. 27

28. Jewer’s and Boyd’s Classification of Mandibular Defects:- H- Lateral defects of any length up to midline including condyle. C- Defects involve central segment containing 4 incisors and 2 canines. L- Lateral defects excluding the condyle 3 lower case letters describe soft tissue component s– Skin. m– Mucosa. sm - Skin and mucosa 28

29. 29

30. Materials used in maxillofacial prosthetics Ideal biological properties The cured material and any released materials should not irritate the supporting tissues. Cured material and any released materials should be nonallergenic. Cured material and any released materials should be non-toxic. · The cured material should not support the growth of microorganisms 30

31. Ideal physical and mechanical properties of maxillofacial prosthetic materials 1. Dynamic properties comparable to tissues 2. High edge strength 3. High elongation 4. High resistance to abrasion 5. High tear strength 6. High tensile strength 7. Low coefficient of friction 8. Low glass transition temperature 9. Low specific gravity 10. Low surface tension 11. Low thermal conductivity 12. Odourless , 13. Non-inflammable 14. No water sorption 15. Softness compatible to tissue 16. Translucent 31

32. Acrylic Resins. Acrylic resins are used in the fabrication of both intra- and extraoral prostheses. In powder form, these resins can be injection- and compression- molded or, in dough form, they can be molded in gypsum molds. Those resins obtained from acids, CH2 =CHCOOH, and methacrylic acids polymerize by additional polymerization. Also, it is easily repaired or relined with either a tissue conditioner, or temporary denture reliner , and it can be quickly and easily processed. 32

33. Polymethyl Methacrylate. Polymethyl methacrylate is a transparent resin of remarkable clarity; it transmits light into the ultraviolet range to a wave length of 0.25. The resin is extremely stable; it will not discolor in ultraviolet light, and it exhibits remarkable aging properties. It will soften at 260°F (125°C), and it can be molded as a thermoplastic material. Between this temperature and 400°F (200°C), depolymerization takes place. 33

34. Silicone Elastomers Polydimethyl siloxane, commonly referred to as silicone, are a combination of organic and inorganic compounds The long-chained polymers, when tied together at various points (cross-linked), create a network that can be separated only with difficulty. This network makes the silicones especially resistant to degradation from ultraviolet light exposure. The process of cross-linking the polymers is referred to as vulcanization. Vulcanization occurs both with and without heat and depends on the catalytic or cross-linking agents utilized. 34

35. Silicones are classified into 4 groups, according to their applications 1.) The first classification is Implant Grade, 2.) The second classification is Medical Grade, which is approved for external use only. This is the material most commonly used in fabrication of maxillofacial prostheses 3.) Clean Grade. 4.) Industrial Grade, which is mostly used for industrial applications. 35

36. HTV silicones Designed for higher tear resistance in engineering applications, this type of polymer requires more intense mechanical milling of the solid HTV stock elastomer compared with the soft putty RTV silicone, especially for incorporating the required catalyst for cross-linking, and for pigmentation. 36

37. Types of HTV Silicones Silastic 4-4514, 4-4515 Q7-4635, Q7-4650, Q7-4735, SE-45240 37

38. Advantages They have improved physical and mechanical properties compared to RTV silicone single component system with unlimited shelf life. Disadvantages they do not possess sufficient elasticity to function in movable tissue beds. Polydimethylsiloxane oligomer may be added to reduce the stiffness and hardness Opaque, difficulty in intrinsic colouration , high superficial surface hardness, and difficulty in processing 38

39. RTV SILICONES Designed for rapid room temperature curing, the RTV silicones continue to serve the needs of maxillofacial restorations but with some limiting aspects. With some grades, internal colouring is difficult. elastomer with the catalyst for the curing (vulcanizing), air entrapment persists in the finished cured prosthesis, which tends to initiate tear and accumulation of skin exudates 39

40. Types of RTV silicones MDX4-4210: Cosmesil A-2186 A-2000 and A-2006 Chlorinated polyethylene Polyphosphazenes 40

41. Metals for framework of definitive obturators Metal frameworks for obturator prosthesis are typically made of Co-Cr alloy; however, Ni, Co or Cr may sometimes cause sensitivity, including not only local responses such as gingivitis and stomatitis but also generalized manifestations like eczema or dermatitis with or without mucosal lesions Titanium and its alloys have very high biocompatibility and excellent corrosion resistance in the oral cavity as titanium oxide that is formed on its surface is highly stable and inert. 41

42. Titanium is less dense than conventional alloys, which is of key importance in view of the large size of obturator prostheses. Titanium frameworks have been reported to be 40 % lighter than Co-Cr frameworks and 60 % lighter than Ni-Cr frameworks. The use of visible light-polymerized (VLP) resins not only reduces weight but also improves oral hygiene since these resins demonstrate a much lower porosity than autopolymerized resins 42

43. MANAGEMENT OF MAXILLARY DEFECTS Resection of the hard and soft palate and related structures result in a variety of anatomic and functional defects in the oral cavity and Oropharynx. Methods of Resection: Palatectomy – The mucosal incisions are outlined to give appropriate margin around the tumour , depending upon the histopathology observed in the biopsy If the soft palate is also involved a generous margin or the entire soft palate is resected. 43

44. If the lesion approaches the greater palatine foramen, then the posterior alveolar ridge and the pterygoid plates should also be resected. After resection, the bony edges are smoothened and contoured, then covered with the periosteum and mucosa. Packing is placed in the defect and an immediate surgical obturator is inserted and wired to the teeth or alveolar ridge Maxillectomy: It is required if the tumour is very malignant and invades the nasal cavity or paranasal sinuses. 44

45. Complete exposure of the maxilla is obtained by the Weber- Fergusson Incision in which the lip is split and the incision extended around the nose up to the orbit and along the eyelid. The orbital rim is spared if the orbital contents have not been invaded The pterygoid plates and the soft tissues of the pterygomaxillary space are resected at the base of the skull using a curved osteotome The wound is packed, the immediate surgical obturator is placed and the Weber- Fergusson incision closed. 45

46. ‘Obturator'. The most common of all intraoral defects of the maxilla are in the form of an opening into the nasopharynx. The prosthesis needed to repair the defect is termed as an 'obturator’ Definition: According to Glossary of Prosthodontic Terms, obturator is a prosthesis used to close a congenital or acquired tissue opening primarily of the hard palate and/or contiguous alveolar/soft tissue structures 46

47. Chalian in 1971 described an obturator as a disc or plate, natural or artificial which closes an opening or defect of the maxilla as a result of cleft palate or partial or total removal of the maxilla for a tumor mass. Obturator is a maxillofacial prosthesis used to close, cover, or maintain the integrity of the oral and nasal compartments resulting from a congenital, acquired, or developmental disease process, i.e. cancer, cleft palate, osteoradionecrosis of the palate. It helps to restore the continuity of the hard palate and oral cavity from nasal cavity, maxillary sinus, and orbit from the oral cavity 47

48. Ideal requirements for maxillary obturator 1. To carry out natural functions such as phonation, deglutition, and mastication 2. Life-like appearance to aid function 3. The design of the prosthesis should easily & swiftly be placed in position both comfortably and securely 4. The prosthesis should be durable for a reasonable period of time, retain its polish and finish 5. Should be easy to clean to maintain hygiene. 48

49. Functions of obturator 1. To close the defect 2. For feeding purpose 3. To keep wound or defective area clean, thus enhance healing of traumatic or postsurgical defects. 4. As a stent to hold dressings or packs post surgically 5. To reduce the postoperative hemorrhage 6. Help to reshape and reconstruct the palatal contour and/or soft palate 7. Improve speech 49

50. Classification of obturator A) The origin of discrepancy: a) Congenital defect obturator. b) Acquired defect obturator. B) The location of the defect a) Labial or buccal reflex obturator. b) Alveolar obturator c) Hard palate obturator d) Soft palate obturator e) Pharyngeal obturator 50

51. C) The type of obturator attachment to the basic maxillary prosthesis a) Fixed obturator b) Hinged or movable obturator c) Detachable obturator D) The physiologic movement of the oral, nasal & pharyngeal tissues adjacent or functioning against the obturator a) Static obturator b) Functional obturator E). Depending on the material used a). Metal obturator b). Resin obturator c). Silicon obturator 51

52. General Outline For Prosthetic Rehabilitation Of Hard Palate Defects Patient is rehabilitated in three phases by an obturator prosthesis that supports the patients through various stages of healing. It involves three phases of treatment a. Immediate surgical obturator b. Transitional obturator c. Definitive obturator 52

53. Immediate surgical obturator or maxillary surgical prosthesis Surgical obturator is defined as a temporary prosthesis used to restore the continuity of the hard palate immediately after surgery or traumatic loss of a portion or all of the hard palate and/or contiguous alveolar structure – GPT Objective-To restore and maintain oral functions at reasonable levels during the postoperative period until healing is substantially completed. 53

54. Advantages of immediate surgical obturator Provides a matrix on which the surgical packing can be placed. -The prosthesis reduces oral contamination of the wound during the immediate post-surgical period. -Enables the patient to speak more effectively postoperatively by reproducing normal palatal contours and by covering the defect. -The prosthesis permits deglutition, thus the nasogastric tube may be removed at an earlier stage. -The prosthesis lessens the psychological impact of surgery by making the postoperative course easier to bear. -The prosthesis may reduce the period of hospitalization, 54

55. Procedure of fabrication of surgical obturator in edentulous patients Alginate impression is made, and cast is obtained If any tumor bulk is present that area of the cast is reduced to normal contour. Avoid extent of the surgical peripheries, especially in soft palate and pterygoid area. Surgical packing will close discrepancies in surgical defect margin & prosthesis margin. Prosthesis can be fabricated with heat-cure resin or autopolymerizing resin (clear resin) to facilitate visualization of the underlying tissues at the time of placement and during initial healing period. 55

56. Surgical obturator in dentulous patients Fabrication of the obturator should be according to a conservative line of resection still allowing the obturator to be used for larger resections. This method allows the surgeon to utilize the obturator regardless of the size of the defect to perform intraoperative adjustments to the obturator. Fabricate the surgical obturator for the most extreme surgical resection, making it fit best even in a difficult situation. The prosthodontist can guide at the time of surgery to perform the modifications & able to modify the obturator to accommodate the teeth that are not resected. 56

57. Transitional or Interim Obturator Definition: Prosthesis that is made several weeks or months following the surgical resection of a portion of one or both maxilla including replacement of teeth in the defect area. This prosthesis when used replaces the surgical obturator that is placed immediately following the resection & subsequently replaced with a definitive obturator – GPT 57

58. Interim obturator is placed when surgical obturator is removed on which surgical dressing is supported. Interim obturator constructed from the postsurgical master cast serves the patient for 4–6months till the maxillary defect heals and matures. Patient should routinely be taught about home care procedures for the regular cleaning of the residual defect, remaining teeth, and the prosthesis. 58

59. -----------------------------------to be continued------------------------------- 59

60. Definitive obturators It is defined as a prosthesis that artificially replaces part or all of the maxilla and the associated teeth lost due to surgery or trauma – GPT Timing will vary depending on - i . Size of the defect -ii. Progress of healing -iii. Prognosis for tumor control -iv. Effectiveness of the present obturator -v. Presence or absence of teeth. 60

61. Reasons for fabrication of a new prosthesis. Periodic edition of interim lining material increases the bulk and the weight of the prosthesis and this temporary material may become rough and unhygienic if anterior teeth are resected, addition can be of psychological benefit if retention and stability are inadequate occlusion contact on the defects side may result in improvement 61

62. Types of obturators Hollow bulb (Closed). Roofless (Open bulb) 62

63. If the obturator is left open- nasal secretions accumulate leading to odour and added weight, if secretion occurs then ,small diagonal opening may be for drainage. - Dificulty in polishing and cleaning the internal surface, from saliva, mucous crusts, food accumulation ,inability to obtain support from the superior aspect in the defect area. 63

64. Advantages of a hollow bulb obturator  Weight of the obturator is reduced, comfortable and efficient.  No excessive atrophy & physiological changes in muscle balance.  Reduces the self-consciousness of wearing a denture  Improves retention & increases physiological function so that teeth and supporting tissues are not stressed unnecessarily.  Decrease, in pressure- aids in deglutition and encourages the regeneration of tissue 64

65. Movement of the obturator prostheses Degree of movement will vary with number and position of teeth available for retention, the size and configuration of the defect, the amount & contour of the remaining palatal shelf, height of the residual alveolar ridge, the size, contour, and lining mucosa of the defect and the availability of undercuts. Lack of retention, stability and support are common prosthodontic treatment problems for patients who have had a maxillectomy. 65

66. Retention Retention is the resistance to vertical displacement of the prostheses 1. Teeth: The number, position, and periodontal status of the remaining teeth are the most critical factors in evaluating the amount of stress that the remaining teeth absorb. Fixed splinting of all remaining teeth indicated to provide dissipation of the stresses directed to primary abutment teeth. If the defect is small & remaining teeth stable- intracoronal retainers might be considered . If the defect is large & some or all remaining teeth are weak- extracoronal retainers should be used 66

67. 2. Alveolar ridge A large ridge with a broad crest is more retentive than a small or tapering ridge crest. Broad palate is more retentive than the high tapering palate. Square arch form is more conducive to retention than the tapering or ovoid arch form. Within the defect retention 3. Residual soft palate: It provides a posterior palatal seal which will minimize the passage of food and liquids above the obturator prosthesis. Extension of the obturator prosthesis onto the nasopharyngeal side of the soft palate will help in this purpose and will also provide retention. 67

68. 4. Residual hard palate: Depending on the location of the line of palatal resection, there will be varied degrees of undercut along this line into the nasal or paranasal cavity. The objective of prosthesis extension is to provide resistance to vertical and horizontal displacement. 5. Lateral scar band: A scar band results after surgical resection at about mucobuccal fold. the lateral scar band also tends to stretch with continued use which may necessitate sequential additions to the prosthesis 6. Height of lateral wall: Utilized for indirect retention. A high lateral wall of an obturator will undergo less vertical displacement with a given defect wall flexure than will a shorter prosthesis lateral wall. 68

69. Stability Resistance to prosthesis displacement by functional forces. Residual maxillary stability: Bracing components of the prosthesis framework can be used to minimize movement in all three directions. Stability within the defect - Maximal extension of the prosthesis in all lateral directions must be provided. Contact of the obturator portion of the prosthesis with these structures like medial line of resection, the anterior and lateral walls of the defect, the pterygoid plates, and the residual soft palate minimizes anteroposterior, mediolateral and rotational movement of the prostheses 69

70. 3. Occlusion: The most important aspect of stability is occlusion. Maximal distribution of occlusal force in centric and eccentric jaw positions is imperative to minimize the prostheses' movement by correctly selecting an occlusal scheme and eliminating premature occlusal contacts. Acrylic resin teeth with a reduced occlusal contact area may be indicated. Altering the cusp angle of posterior teeth may influence the stability of the prosthesis. 70

71. Support Resistance to movement of a prosthesis towards the tissue. Residual maxilla In the residual maxilla, the primary areas available for support are the residual sound teeth, the alveolar ridge, and the residual hard palate. Only sound teeth should be selected to provide support in the remaining segment for a large prosthesis. 71

72. 72

73. 73

74. 74

75. 75

76. 76

77. 77

78. REHABILITATION OF SOFT PALATE DEFECTS The term velum is often used interchangeably with the preferred soft palate. Abnormalities of the soft palate can occur in different ways. The resultant defects can be grouped into three categories: congenital, acquired, or developmental. When some or all anatomic structure of the soft palate is absent, the term palatopharyngeal insufficiency is applied. When the soft palate is of adequate dimensions but lacks movement because of disease or trauma affecting muscular and/or neurologic capacity, the term palatopharyngeal incompetence applies. 78

79. The term palatopharyngeal inadequacy includes incompetence and/or insufficiency but may also suggest a reduction or absence of pharyngeal wall function. A pharyngeal obturator prosthesis, which may also be called a speech aid or speech bulb prosthesis, extends beyond the residual soft palate to create separation between the oropharynx and nasopharynx helps to provides a fixed structure against which the pharyngeal muscles can function to effect palatopharyngeal closure 79

80. 80 PRO S T H EIS PALATAL OBTUR ATOR PALATAL LIFT PROSTH E SIS SPEECH BULB PROSTH E SIS

81. Palatal lift prostheses. The prosthetic management of VP insufficiency is carried out by means of a pharyngeal obturator, whereas VP incompetence is traditionally managed by a palatal lift prosthesis A palatal lift prosthesis addresses palatopharyngeal incompetence by physically displacing the dysfunctional soft palate in the hope of closing the palatopharyngeal part enough to mitigate hypernasal speech and/or prevent nasopharyngeal regurgitation of liquids or solids during the pharyngeal phase of swallowing. 81

82. Advantages of palatal lift prostheses The gag response is minimized because of the superior position and the sustained pressure of the lift portion of the prosthesis against the soft palate. The physiology of the tongue is not compromised because of the more superior position of the palatal extension. The access to the nasopharynx for the obturator is facilitated. The lift portion may be developed sequentially to aid patient adaptation to the prosthesis. - Application to a diverse patient population. 82

83. Fabrication of Prosthesis: Surgical treatment is not considered as an option, Upper and lower perforated stock trays are selected. Upper trays are modified with orthodontic wire, and wax extension is made into the defect to record the defect. Upper & lower preliminary impressions are made with irreversible hydrocolloids. The upper impression also recorded the defect and diagnostic casts are fabricated 83

84. 84

85. Autopolymerizing acrylic resin having pharyngeal extension with following factors are to be kept in mind that 5 mm gap between the bulb and posterior pharyngeal wall is kept and angle of the bulb is kept approximately 20° relative to the palatal plane. 85

86. Border molding with low-fusing impression compound - by recording all the functional movements of the soft palate, by asking the patient to perform side to side movement, bend head in front and back direction following a circular path. Patient is asked to swallow which helps to record the anterior and posterior tonsillar pillars, Passavant’s ridge, and the anterior tubercle of the atlas 86

87. Upper final impression was made with medium body polyvinyl siloxane and lower with ZnOE 87

88. 88

89. SPEECH BULB PROSTHESIS A speech bulb obturator, also known as a speech aid appliance, is also a removable device that is used for the treatment of VP insufficiency . When the velum is short relative to the depth of the posterior pharyngeal wall, resulting in a VP opening during the speech, the bulb serves to fill in the pharyngeal space. The bulb sits in the nasopharynx to occlude the VP port during the speech. This improves the speech and can also improve swallowing because it eliminates nasal regurgitation. It can also be combined with partial or complete dentures. 89

90. 90

91. MEATAL OBTURATOR It is special type of obturator that extends up to nasal meatus. It establishes closure with nasal structures at a level posterior & superior to posterior border of hard palate. The closure is established against the conchae & roof of nasal cavity. It separates oral & nasal cavities. Indicated in patients with extensive soft palate defects 91

92. 92

93. 93

94. DISADVANTAGES OF MEATAL OBTURATORS Nasal air emission cannot be controlled because it is in an area where there is no muscle function. Nasal resonance will be altered. 94

95.   Prosthetic management of Cleft lip and palate Surgical closure It is the treatment of choice for palatal cleft closure. It superior to prosthetic closure by obturator. If cleft involves the lip, it is advisable to repair it as early as possible (6 wks. after birth) to facilitate feeding and improve appearance. Surgical closure of palatal cleft is better to be done before the end of the second year of age. B. Prosthetic restoration feeding appliance Simple palatal plate to close cleft. Speech aid obturator. C. Orthodontic treatment and arch expansion. 95

96. Time consideration in treatment of cleft palate 96

97. 97

98. FEEDING OBTURATOR Neonates born with a cleft palate have difficulty in feeding, which leads to failure to thrive Oro-nasal communication diminishes negative pressure, makes suckling difficult & causes nasal regurgitation. Orogastric and nasogastric tubes can be effective but should be used only for a limited length of time. 98

99. Advantages It helps in feeding Reduces nasal regurgitation Prevents tongue from entering the defect Allows spontaneous growth of palatal shelves Contribute to speech development Reduces incidence of otitis media and other pharyngeal infections 99

100. 100

101. Presurgical naso alveolar moulding As the clefts are deficient in hard and soft tissue elements, they present a significant surgical challenge to achieve a functional and cosmetic outcome. Even a mild incomplete unilateral cleft lip in the absence of a cleft palate can be associated with a nasal deformity. The primary aim of PNAM is a reduction in the soft tissue and cartilaginous cleft deformity to facilitate surgical soft tissue repair in optimal conditions under minimum tension to minimize scar formation. 101

102. It allows stimulation and redirection of growth for the controlled predictable repositioning of the alveolar segments and gives the ideal arch form, normalizes the tongue position, aids in speech development, improves appearance and gives a psychosocial boost, and improves feeding and bone contour. 102

103. Objectives of presurgical nasoalveolar molding To provide symmetry to severely deformed nasal cartilages To achieve projection of the flattened nasal tip To provide nonsurgical elongation of the columella To improve the alignment of the alveolar ridges and reduce the distance between the cleft lip segments. 103

104. 104

105. Treatment of congenital defects Effects of cleft palate and lip 1. Speech – lack of valvopharyngeal closure leads to escape of air through the nose (nasal speech) 2. Deglutition – greatly impede the feeding, regurgitation and escape of fluids through the nose takes place . 3. Mastication – impaired due to escape of food through the nasal cavity and due to missing teeth and malocclusion . 4. Esthetics is affected seriously especially in cleft palate/lip. 5. Deterioration of the general health 6. Psychological trauma . 7. Recurrent infection of the air ways and middle ear . 105

106. ----------------------------------To be continued--------------------------------- 106

107. Cantor and Curtis Classification of Mandibular Defects Class I:- Radical alveolectomy with preservation of mandibular continuity. Class II:- Lateral resection of the mandible distal to the cuspid area. Class III:- Lateral resection of the mandible to the midline. Class IV:- Lateral bone graft and surgical reconstruction. Class V:- Anterior bone graft and surgical reconstruction. Class VI:- Anterior mandibular resection without surgical reconstruction 107

108. Class 1 defect TISSUES RESECTED Portion of alveolar process and body of mandible Lingual and buccal sulcus mucosa Portion of base of tongue and mylohyoid muscle Lingual and inferior alveolar nerves Sublingual and Sub maxillary salivary glands Sometimes anterior part of digastric muscle 108

109. FEATURES Least debilitating. Can raise the floor of the mouth causing reduction in tongue mobility. Ability to shape and control the tongue may be lost due to loss of some intrinsic muscles. 109

110. Class 2 defect TISSUE RESECTED condyle, ramus and body of mandible distal to canine mylohyoid, hypoglossal, ant belly of digastric, Internal pterygoid,masseter , external pterygoid, Pharangoglossal & palatoglossal muscles, most of intrinsic muscles of tongue. hypoglossal , lingual and inferior alveolar nerves adjacent buccal and lingual mucosa 110

111. FEATURES Speech, swallowing, saliva control, manipulation of food impaired. Facial disfigurement Disarticulation and loss of muscles of mastication which will hamper mandibular movements Taste ,sensory and motor losses more extensive as compared to class 1 111

112. Class 3 defect TISSUE RESECTED all those described in class 2 additionally anterior portion of the mandible, geniohyoid, genioglossus, remaining portion of mylohyoid muscle with lingual and buccal mucosa. 112

113. FEATURES Restricted tongue mobility due to loss of the tip of tongue and genioglossus muscle Speech, swallowing, saliva control, and manipulation of food severely restricted. Facial disfigurement is worse due to loss of the anterior part of the mandible Disarticulation and reduction in the amount of basal bone reduce prosthodontic prognosis. 113

114. Class 4 defect Lateral bone and split-thickness skin or pedicle graft can be performed on patients who have had: radical alveolectomies resection of mandible distal to cuspid with or without disarticulation. 114

115. Class 5 defect. TISSUE RESECTED anterior portion of the mandible large bilateral portions of mylohyoid, geniohyoid genioglossus and anterior digastric muscles bilateral lingual and inferior alveolar nerves bilateral submaxillary and sublingual salivary glands mucosa of lower lip anterior floor of mouth ventral surface of tongue 115

116. Class 6 defect It is similar to a class V patient, but the continuity of the mandible has not been restored surgically. Because each lateral fragment moves independently, the prognosis for a removable prosthesis is poor and fabrication is not recommended 116

117. With only one-half or two-thirds of the mandible remaining, the stability, support, and retention of the mandibular denture are compromised. Due to radiation therapy either prior to or after surgery, the oral mucosa is atrophic and fragile, predisposing to soft tissue irritation and ulceration. The reduction in saliva output, and the thick mucinous nature of the saliva that remains after therapeutic levels of radiation, impairs retention and stability of the future prosthesis. 117

118. The angular pathway of mandibular closure induces lateral forces upon the dentures which dislodge them. The deviation of the mandible creates abnormal jaw relationship which prevent ideal placement of the denture teeth over their supporting structures The impairment of motor and sensory control of the tongue, lips and cheek impairs the ability of the prosthesis to stay in its original position 118

119. Factors affecting treatment of mandibulectomy patients 119

120. 1.Location & Extent of Mandibular Defect Marginal defects have better prognosis than discontinuity defects . Marginal alveolectomy -Least debilitating Main problems – loss of vertical ridge height and vestibular depth 120

121. The farther anterior the defect, the more disfiguring and functionally debilitating it is likely to be. Reason: Loss of key muscle attachments(genioglossus and geniohyoid) located in anterior mandible that control tongue function and mobility. Defects of the symphyseal region are most debilitating and difficult to treat. 121

122. 2. Presence of remaining natural teeth/pre-existing implants Greater the number of teeth ,better the prognosis Remaining natural teeth in linear relationship are unlikely to provide adequate abutments for prosthesis than teeth arranged in two dimensions 122

123. 3.Degree of post mandibulectomy rotation and deviation Mandible deviates towards the defect and rotation of mandibular occlusal plane inferiorly During mandibular closure, mandible rotates around occlusal contacts on un-resected side, and remaining teeth on resected side drop further out of occlusion. This movement is called FRONTAL PLANE ROTATION. 123

124. Deviation: Due to Primarily due to loss of tissue involved in surgical resection. Rotation: Due to Pull of the suprahyoid muscles on the residual fragment causing inferior displacement and rotation around the fulcrum of the remaining condyle. And Gravity. 124

125. 5.Available mouth opening Trismus –due to surgical trauma Physical therapy should be started immediately. Scar tissue formation will further reduce mouth opening 125

126. 6.Functional limitation of tongue Frequently the surgical wound is closed by suturing the remaining tissues of the floor of the mouth or tongue to the remaining buccal tissues 126

127. This compromises: - Speech - Swallowing - Mastication - Control of food bolus - Ability to control removable prosthesis In such cases consideration is given to lowering the anterior occlusal plane or arranging the teeth slightly lingually. 127

128. 7.Compromised vestibular extensions Vestibular depth is critical for stability and peripheral seal It is also critical when mandibular continuity is restored with bone grafting and implants are 128

129. 8.Skin grafting Skin grafts are used for surgical reconstruction either as lining for the surface of resected soft tissue or as part of skin and connective tissue grafts such as pedicle flaps, free flaps etc. Advantages 1. Effective load-bearing tissue. 2. Can withstand pressure and chafing from the prosthesis. 3. Protects underlying bone and connective tissue well due to rapid turnover of keratin-producing cells. Disadvantages 1. No sensory innervations. 2. Full-thickness grafts may incorporate hair 129

130. 9.Radiation therapy Irradiated tissue is fragile ,sensitive to manipulation, desiccated, slow to heal, prone to infection and at risk of osteoradionecrosis 130

131. 10. Altered anatomic relationships following restoration of mandibular continuity Reconstruction of anterior defects grafting frequently results in a graft that is deficient anteriorly. - Results in a severe Class 2 like situation. The prosthodontic difficulties seen in rehabilitating such a patient are:- - Inability to provide proper lip support. - Speech problems associated with mandibular dentition placed too far lingually. - Inability to control food bolus due to lack of motor control 131

132. Excessive display of mandibular teeth due to patients inability to maintain normal lip posture. Difficulty gaining adequate space for prosthesis placement without encroaching on function of tongue. Misalignment of remaining un resected mandibular fragments and resultant relationship between maxillary and mandibular teeth. 132

133. Reconstruction of posterior defects - More predictable from prosthodontic point of view as compared to anterior defects. 133

134. 11. Previous experience with removable prosthesis Indicator of how successful rehabilitation will be, particularly edentulous patients 134

135. Prosthodontic rehabilitation 135

136. All basic principles of complete denture construction must be considered and modified because of the unusual anatomic and functional situation. TREATMENT PLAN  Exercise regimen  Reconstruction  Definitive Guidance Prosthesis 136

137. Impressions Maximum extension and tissue coverage should be recorded with the preliminary impression Irreversible hydrocolloid is used with an altered/sectional stock tray. Conventional border molding and Master impression is used to achieve better peripheral seal. 137

138. Jaw relations Centric relation does not exist in partially mandibulectomy patients with discontinuity defects because there is only one condyle to guide the mandible. Interestingly they do have proprioception for a repeatable area but not a repeatable point contact when asked to open wide and close the mandible 138

139. In the maxilla, the wax rim used to record the centric occlusion registration record is widened on the un resected side towards the palatal side in order to account for deviation of the mandible. Vertical dimension of occlusion is difficult to determine due to mandibular deviation and impaired motor and sensory function. Traditional methods are contraindicated hence VDO is recorded with mandible closing as much as possible. VDO determination should rely on lip competence, facial appearance and speaking space parameters. 139

140. The patient is instructed to move the mandible as far as possible toward the untreated side. Then patient was asked to close with his own muscular force when the mandible was manually guided. This records a functional maxillo mandibular relationship which the patient can attain. 140

141. Teeth selection and arrangement Artificial denture teeth of zero degree cuspal angulations are selected and arranged to achieve monoplane occlusion and to allow for lateral freedom of mandibular movements. With the lingual inclination of the residual mandible, and with elevation of the buccal shelf, placement of posterior teeth to the buccal of the residual alveolar ridge centers the forces of occlusion more favorably After all the mandibular teeth and the maxillary teeth have been arranged, ramps are developed for the maxillary prosthesis in base plate wax. These ramps usually 5-10mm wide and should provide 2-4mm horizontal overlap with the mandibular posterior teeth. 141

142. Depending upon severity of deviation, the ramp on the nonsurgical side usually extends palatal to the maxillary alveolar ridge, and the ramp on the surgical side extends buccal to the alveolar ridge 142

143. Cast partial denture 143 Indicated for patients with marginal mandibulectomies Ideal prosthesis bearing surface is split thickness graft ; it is thin, firmly attached to the mandible and will not move with movement of tongue, floor of mouth or cheek.

144. Management of mandibular deviation Use of skin grafts and flaps for wound closure Inter maxillary fixation at time of surgery Intense physiotherapy to minimize deviation Mandibular Guidance Prosthesis 144

145. IMF • This type of fixation maintains the residual mandible in the proper maxillo mandibular position and permits healing of the defect and the associated scar formation with the teeth in occlusion. If Inter maxillary fixation is used in immediate postoperative period, very little muscle retraining may be needed. • The degree of deviation seems to be inversely proportional to the length of time the imf has been done. 145

146. MANDIBULAR GUIDANCE PROSTHESIS In discontinuity defects mandibular guidance therapy can be instituted to retrain the patient’s neuromuscular system to provide an acceptable maxillo-mandibular relationship of the residual portion of the mandible which permits occlusion of the remaining natural teeth 146

147. Classification. Palatal-based guidance prosthesis • Maxillary inclined plane prosthesis. • Positioning prosthesis with palatal flange Widened maxillary occlusal table 2) Mandibular-based guidance prosthesis 147

148. Maxillary inclined plane prosthesis The prosthesis is retained using inter proximal ball clasps or adam’s clasps. Mandibular closure results in the progressive sliding of the remaining mandibular teeth up the incline in a superior and lateral direction until the occlusal contact is reached. 148

149. Positioning prosthesis with palatal flange Patients who are able to use their presurgical inter cuspal position after mandibular resection often complain of mandible deviating towards the defect side during sleep. • On awakening they have difficulty reestablishing normal occlusal contact and also muscle pain. Flage extending from palate inferiorly into the lingual vestibule between lateral border of tongue & lingual surface of the mandible can be formed in the mouth with auto polymerizing acrylic resin. 149

150. Prevent medial deviation of un resected mandible even when the mouth is open. The flange should contact only the lingual surfaces of mandibular teeth and it should not impinge on the lingual mucosa of the mandible throughout the opening and closing movements. 150

151. Widened maxillary occlusal table Patients who cannot attain the ideal medio lateral position of the remaining segment and an acceptable occlusal contact of the teeth, in spite of the use of various guidance prostheses, a palatal ramp or a widened maxillary occlusal table using double row of teeth may be used. This provides a surface against which the remaining mandibular teeth occlude against the maxillary teeth 151

152. 152

153. 153

154. Mandibular lateral guide flange prosthesis Used in patients who can achieve proper medio lateral position of the mandible but cannot hold that position for adequate mastication 154

155. The guide flange is attached to a cast mandibular removable partial denture. It can be either molded in wax at the try-in stage and processed in clear acrylic resin or a heavy wire loop may be used. The guide flange is extended into maxillary muco-buccal fold superiorly & diagonally on non defect side without impinging on the muco-buccal fold. 155

156. CONCLUSION 156

157. Reference. Ackerman AJ The prosthodontic management of oral and facial defects J Prosthet Dent,1955;5:413-432 Scannel JB Practical considerations in dental treatment of patients with head and neck cancer J Prosthet Dent,1965;15:764-778 Kelly EK Partial denture design applicable to the maxillofacial patient J Prosthet Dent,1965;15:168-173 • Swoope CC Prosthetic management of resected edentulous mandibles J Prosthet Dent,1969;21:197-201 Cantor R and Curtis TA Prosthetic management of edentulous mandibulectomy patients Part 1 J Prosthet Dent,1971;25:447-455, Part 2 J Prosthet Dent,1971;25:547-555, Part 3 JProsthet Dent,1971;25:671-78. 157