Treatment planning for the edentulous maxilla.pptx

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1. REDDY PRIYA DARSHINI Treatment planning for the edentulous maxilla

2. Contents Introduction Diagnosis Extra oral examination Facial and lip support Smile line and lip length. Intra oral examination Mucosal thickness Bone quantity and quality Interarch space Incisal edge position

3. Implant treatment plan Occlusal forces Implant size determination Implant number Implant design Guidelines for implant location Arch form Treatment selection Fixed restorations Implant overdentures (RP – 5 and RP – 4 )

4. Sinus augmentation procedures. Subantral option 1 Subantral option 2 Subantral option 3 Subantral option 4 Sinus balloon lift. Conclusion References

5. introduction Tooth extraction in anterior part of maxilla – horizontal and vertical resorption. Vertical distance between alveolar crest and base of the nasal sinuses provides a limiting factor for placement of implants. Posteriorly – vertical and horizontal atrophy Pneumatisation of maxillary sinuses.

6. introduction A fixed restoration or an implant over denture should be decided only after all the diagnostic criteria are evaluated. These include quality and quantity of bone available to support the implants, lip line, lip support and aesthetic demands. Implants should be placed only after a definitive treatment plan has been established as implant positions vary depending on the type of prostheses to be delivered.

7. Extra-oral examination Facial and lip support Assessment of the patient’s facial support with and without the denture in place with the patient facing forward and in profile needs to be made so we can determine which type of prostheses would be more suitable Facial support if inadequate is obtained mainly by the buccal flange of a removable restoration Lip support is derived from the alveolar ridge shape and cervical crown contours of the anterior teeth Jiv raj etal ; British dental journal; vol 201, no 5, 2006

8. Smile line and lip length Movement of the upper lip during speech and smiling should be evaluated. High smile line additional gingiva exposed and Low smile line less than 75% of the maxillary anterior teeth are displayed.

9. Intra – oral examination mucosal thickness Provisional restorations in the mouth. Interdental papillae are very difficult to generate in full arch implant rehabilitations. The aesthetics must be visualised in provisional restorations. Pink porcelain was used to close interdental spaces and provide improved aesthetics and speech

10. Mucosal thickness When there is excessive hard and soft tissue loss and the appearance of interdental papilla can only be made up through the use of gingival coloured ceramics or acrylic resin . A thick mucosa is easier to mould for an interimplant trigonum than a thin mucosa. Thick mucosa can also help hide abutment margins and facilitates correct emergence of the clinical crown. Where angulated abutments are required the mucosa can facilitate hiding the pronounced titanium collar. Thin tissue – consideration soft tissue grafting in order to change the tissue type to a more favourable one.

11. Bone quality and quantity In the pre maxilla the tooth position may be much further forward than the implant position and this may pose certain biomechanical disadvantages. In the posterior maxilla the resorption pattern may be so severe that a cross bite relationship may have to be used or alternatively the tooth position may have to be cantilevered facially so as to re-create the vertical and horizontal tooth relationships that existed prior to extraction.

12. Bone quality and quantity Computed tomography scans and tomograms reveal the three dimensional architecture of the bone and provide the surgeon with precise representation of the availability and location of bone . To obtain maximal benefit from such a scan a radiographic template can be used. Titanium pins or gutta percha markers should be incorporated into an acrylic resin duplicate of the diagnostic denture set up The markers oriented perpendicular to the occlusal plane and should end apically at the height of the prospective clinical crown margin.

13. Bone quality and quantity When a patient has been edentulous for a significant period of time, pneumatisation of the sinuses makes placement of implants very difficult. Maxillary sinus lift procedures, augmentation with iliac bone graft can be done. But, these procedures are traumatic procedures. So, With information from the CT scan implants can be inclined to avoid the maxillary sinuses, or alternative procedures that use existing anatomical sites that offer reduced morbidity and minimal invasion of the existing structures can be used.

14. Bone quality and quantity Zygomatic implants can be placed to engage the zygomatic bone inferolateral to the orbital rim and provide anchorage for a fixed prosthesis in conjunction with anterior implants. Implants can also be placed in the maxillary tuberosity to provide support

15. Bone quality and quantity In the edentulous maxilla type 3 or type 4 bone quality is often found. This quality of bone often dictates over engineering at time of implant placement. Additional implants are placed when the surgeon experiences bone of poor quality, the rationale being if one implant were to fail the restorative dentist would still be able to progress with the anticipated prosthesis.

16. Inter arch space Conventional screw retained implant prostheses have been constructed with 10-12 mm between the edentulous ridges and the opposing occlusal plane. It provides sufficient space for bulk of restorative material and also permits a prosthesis design to establish aesthetics and hygiene. If space is limited, re-establishing a patient’s vertical dimension or altering the opposing occlusion should be considered

17. Inter arch space A conventional overdenture requires additional space. Guidelines for space requirements are between 12-16 mm. Heat processed resin requires 2-3 mm to provide adequate strength as a denture base material. Space is also required for the prosthetic tooth. In the maxilla it is advisable to splint implants when used for overdenture prostheses and as a result 2-3 mm of space may be required to accommodate the necessary bulk for the tissue bar and any retaining clips

18. Incisal edge position The axial inclination of the central incisor should be placed so as to provide adequate support for the upper lip. Once the crown length, angulation and coronal form have been determined the distance between the cervical crown margin and residual bone crest can be assessed. To determine if a fixed or removable restoration would be appropriate a wax try in is done without a flange.

19. For a fixed restoration – clinical crown should ideally end up at the soft tissue level of the alveolar ridge. In this situation minimal resorption would have occurred, inter arch space will be favorable and an optimal tooth lip relationship is present

20. When a large vertical distance exists between the cervical aspect of the tooth and the alveolar ridge but the tooth-lip relationship is favourable pink ceramic may be used to disguise the tooth length and a fixed restoration is still possible

21. When there is both a vertical and horizontal discrepancy between the ideal position of the tooth and the alveolar ridge, and the tooth lip relationship is not optimal this may be an indication for use of a removable prosthesis. The flange will provide adequate lip support and the teeth can be positioned appropriately to satisfy the parameters of aesthetics

22. Implant treatment plans High occlusal forces Bite force in posterior > anterior teeth Anteriors – 35-50 lb/in². Molar region – 200-250 lb/in². Maxillary molars have 200% more surface area than the premolars. These features reduce stress as well as strain to bone.

23. Implant size determination Primary factor for implant size – necessary distance from adjacent implant. 3mm between 2 implants – to accommodate eventual bone loss and maintain interseptal bone levels. Ideal diameter of implant should also consider faciopalatal bone width. If < 1.5mm bone, vertical defect becomes horizontal defect and tissue recedes when it is thin, or forms pocket when thick.

24. Implant size determination Amount of force transmitted to implant body and abutment screw is also a consideration for implant diameter. Larger the diameter, less stress to crestal bone and components. If larger implant diameter has less surrounding soft tissue and is more difficult to control the creation of a papilla, then smaller diameter implants are indicated in esthetic zone.

25. Implant size determination When implants are out of the esthetic zone, diameter of implant is more related to the amount of force applied to the implant – bone – prosthetic system. 3.7mm to 4.2mm diameter implant in premolar and 5mm diameter implants in molars, because force factors are greater and bone density poorer. Ideal implant diameter is 5 – 6mm for maxillary molars. Because Ti is 5-10 times more rigid than natural teeth, the modulus of elasticity for an implant of sizes greater than 6mm may be too great and may cause shielding and bone loss.

26. Implant size Implant diameter – effective method to increase surface area. In a 12 year retrospective study conducted by Fanuscu etal of 653 sinus grafts revealed 14 implant failures by implant fracture at the neck of small diameter implants Minimum 4 mm or 5 mm implants encouraged Length of implants directly related to implant width, design, amount of forces and bone density. Eg : 4mm threaded root form implants should be 12mm of length in D3 bone, or 5mm of atleast 12mm in D4 bone.

27. Implant number Decrease crestal stresses One implant for each missing tooth If stress factors are magnified, 2 implants for each missing molar Implants should always be splinted together to reduce stresses to the bone.

28. Implant design Threaded implant 30 - 200% greater surface area Roughened surface conditions or HA coatings– Increase the rate of osseous adaptation to implants, provide greater initial rigid fixation, increase the surface of bone contact and amount of lamellar bone, and give relative greater strength of the coronal bone around the roughened surface implants.

29. Arch form Dental arch form - Number and position of implants Residual ridge form

30. Edentulous arch forms are Ovoid-most common. Tapering- found in class II skeletal patients as a result of Para functional habits during growth and development. Square. may result from initial formation of the basal skeletal bone Labial bone resorption of the premaxilla region when anterior teeth are lost earlier than the canine and posterior teeth.

31. Square arch form Due to canine position – lateral and central incisors not cantilevered facially. Mandibular excursions and occlusal forces reduced on canine implants. Reduced forces – forces lowest in incisor region Square arch in maxilla has less cantilevered forces

32. Ovoid arch form Three implants in premaxilla. 2 canine and 1 central incisor. Additional implant – resists additional forces created in this arch form, enhances prosthesis retention, and reduces risk of abutment screw loosening.

33. Tapered arch form Anterior teeth are cantilevered facially from canine position, with increased forces in centric occlusion and during mandibular excursions 4 implants in premaxilla

34. Guidelines for implant locations Bilateral midcanine position is a key implant position and is planned for 4mm diameter implants. Center of first premolar is planned 7mm distal to center of canine implant. This is an optional implant site when parafunction is moderate to severe. Center of second premolar is 7mm distal from first premolar site. For 4.1mm diameter implant on each side. Key implant position.

35. Guidelines for implant locations 4. Center of first molar is 8-10mm distal from mid second premolar implant. This places the implant in the distal of first molar and increases the A-P spread. Implant should be 6mm in diameter. Key implant position. 5. Centre of second molar is 8-10mm distal from centre of first molar. This position is most important for edentulous arch with tapered dentate arch form, D4 bone types, or severe force factors.

36. Edentulous maxilla Complete denture Implant retained and supported over denture No treatment Fixed implant supported restorations Implant retained and tissue supported over denture

37. Implant overdentures 2 treatment options are available for maxillary implant overdentures. Independent implants and cantilever bars are not recommended because bone quality and force direction are severely compromised. 2 treatment options are – RP – 5 restoration with 4 - 6 implants with some posterior soft tissue support. RP – 4 restoration with 7 – 10 implants which is completely supported, retained, and stabilised by implants.

38. Option 1 : maxillary rp – 5 implant overdenture Maxillary denture – good retention, stability, support Maxillary RP – 5 Implant Overdenture – rock and has more movement than a denture, as the anterior implants act as a fulcrum under the prosthesis. Major advantage – maintainence of anterior bone and less expensive treatment option. Implant number and location important than implant size But, implant should be atleast 9mm in length and 3.5mm in diameter.

39. Implant position Key implants – bilateral canine regions. Atleast 1 implant in central incisor region Secondary implants – first or second premolar region

40. Benefits – Retention and stability from implants Posterior support from soft tissue Maintenance of premaxilla bone – implant stimulation

41. Option 2: maxillary rp - 4 implant overdenture 7 – 10 implants Rigid during function Maintains greater bone volume Lip support – labial flange if loss of bone in premaxilla

42. Key implant position Bilateral canines Distal half of first molar Additional implants Bilateral 2 nd premolar Atleast 1 anterior implant between canines Option 2: maxillary rp - 4 implant overdenture

43. When force factors greater – second molar position to increase A-P spread and improve biomechanics of system Tapered arch – 1 implant in premaxilla Implants splinted together. 4 or more attachments positioned around arch. Palatal coverage – prevents speech problem and food impaction. Option 2: maxillary rp - 4 implant overdenture

44. Fixed prosthesis design More than 15mm crown height space – removable prosthesis favourable If fixed restoration is considered – elongated teeth and needs gingival tone. Greater impact force on implant and increased crown height – results in increased moment of forces on implants, risk of material fracture.

45. Zarb etal 1987 – fixed complete denture hybrid prosthesis When CHS is 15mm or more Has a smaller metal framework, denture teeth, acrylic resin Advantages- Esthetic Replaces teeth and soft tissue in appearance Light weight Easier to repair. As Acrylic resin acts as intermediary between porcelain denture teeth and metal substructure, impact force during dynamic occlusal loading may be reduced compared with porcelain metal restoration.

46. Maxillary sinus

47. Expansion of the maxillary sinus Primary pneumatization – 3 months of fetal development Second pneumatization – prenatally Postnatally and until 3 months of age – growth of sinus -pressure exerted by eye on the orbit floor and developing dentition

48. 5 months – triangular area Sinus grows apically Progressively replaces space occupied by developing dentition

49. 12 years – extends to plane of lateral orbital wall , sinus floor level with floor of nose Main development of antrum – eruption of permanent dentition Anteroposteriorly – sinus expansion – growth of midface – eruption of third molars

50. 4 th expansion – loss of posterior teeth in inferior lateral aspects

51. Treatment of posterior maxilla Avoid sinus Place implants and perforate sinus floor

52. Treatment of posterior maxilla Use subperiosteal implants Perform horizontal osteotomy, interpositional bone grafting, endosteal implants Elevate sinus floor during implant placement

53. Treatment of posterior maxilla Lateral wall approach sinus graft and simultaneous or delayed implant placement

54. Treatment selection 4 options – available bone height between floor of the antrum and the crest of the residual ridge

55. Treatment Height (mm) Procedure Healing time (months) graft Healing time (months) implant SA – 1 > 12 Div A root form implant 4-6 SA – 2 10-12 Sinus lift; simultaneous Div A root form placement 6-8 SA – 3 5-10 Lateral wall approach sinus graft; delayed Div A root form placement 2-4 4-8 SA – 4 < 5 Lateral wall approach sinus graft; delayed Div A root form placement 6-10 4-10

56. Sufficient available bone height for placement of endosteal implants. 12 mm implant height ,4 mm diameter threaded implant Subantral option 1 : Conventional implant placement

57. Subantral option 1 Narrower bone volume (Division B ) – osteoplasty or bone augmentation Less than 2.5 mm of width is available (Division c-w) – increase width with onlay autogeneous bone grafts Progressive loading in D3 or D4 bone

58. Subantral Option 2 : Sinus lift and simultaneous implant placement 10- 12 mm of vertical bone present Antral floor elevated through implant osteotomy

59. Depth of osteotomy is 1-2 mm short of floor of antrum and involved several instruments. Curettes – remove bone until reaching floor of sinus Once exposed floor was fractured with an osteotome and membrane elevated with cupped shaped osteotome. OSTEOTOME TECHNIQUE by tatum Khoury; Bone Augmentationin Oral Implantology

60. OSTEOTOME TECHNIQUE Extensive surgical procedure can be avoided and can be performed simultaneously with implant placement. The disadvantages are the uncertainty of possible perforation of the sinus membrane, ridge fracture (extremely narrow ridge), and patient discomfort (tapping). Indicated for a flat sinus floor, when residual bone height is at least 5 mm, and when crestal bone width is adequate for implant installation. The osteotome technique is contraindicated in patients with a history of inner ear complications and vertigo and for an oblique sinus floor (> 45° inclination). The Maxillary Sinus: Challenges and Treatments for Implant Placement Georgios Tasoulis, Suellan Go Yao, The Compendium of Continuing Education in Dentistry

61. OSTEOTOME TECHNIQUE by summers Increase Primary stability of implants at posterior maxilla. Concept – maximum preservation of osseous tissue by compressing trabecular channels and increasing their density The osteotome is pushed apically, laterally displacing the buccal and palatal bones, while the concave tip with a sharpened end of the osteotome pushes bone apically. Contact between instrument and schneiderian menbrane avoided – to protect its integrity. Khoury; Bone Augmentationin Oral Implantology

62. OSTEOTOME TECHNIQUE The osteotomy is prepared to within 1 mm to 2 mm of the sinus floor, then widened with the Nos. 2 and 3 osteotomes . Bone is placed into the osteotomy , and the osteotome is advanced with light malleting (no more than 2 mm). More bone is added, and the procedure is repeated at least three times. When the sinus floor is displaced and the graft is freely moving, the implant is tapped into place and acts as the final osteotomy Summers RB. The osteotome technique, Compend Contin Educ Dent . 1994;15(6):698-710 Khoury; Bone Augmentationin Oral Implantology

63. Nkenke etal – 2001- Study was conducted to analyse bone remodelling after implant placement using osteotome technique – study showed increased new bone formation, and improved bone implant contact- thus improving primary stability. Nkenke , Microscopic analysis of bone remodelling after installation of implants using osteotome technique, Clin. Oral Implants Res 2002; 13:592-602 OSTEOTOME TECHNIQUE

64. Subantral Option 2: Sinus lift and simultaneous implant Worth and Stoneman – Halo formation – phenomenon of bone growth under an elevated sinus membrane. They observed natural elevation of sinus around teeth with periapical disease. This elevation of sinus resulted in new bone formation once the tooth infection is eliminated Carl E.Misch; Contemporary implant dentistry

65. Subantral option 3: Sinus graft with immediate or delayed endosteal implant placement At least 5 mm of vertical bone and sufficient width present Tatum lateral maxillary wall approach -performed superior to residual alveolar bone Graft – space occupied by the sinus Carl E.Misch; Contemporary implant dentistry

66. Contraindications are excessive interarch distance due to unfavorable crown-to-root ratio, acute or chronic unresolved sinusitis, current sinus pathology (eg, cysts or tumors), lodged root tips in the sinus, history of heavy smoking, a systemic compromise, and psychological problems. Subantral option 3: Sinus graft with immediate or delayed endosteal implant placement Carl E.Misch; Contemporary implant dentistry

67. The decision to use the one- or the two-stage technique is mainly based on the amount of residual bone available and the possibility of achieving primary stability for the inserted implants. One-stage sinus floor elevation with simultaneous implant placement Two-stage sinus elevation (delayed installation of the implant). The grafted site matures in approximately 6 to 10 months, according to Wallace et al. Subantral option 3: Sinus graft with immediate or delayed endosteal implant placement

68. Endosteal implants inserted the same time as sinus grafts > 5mm bone height 6mm bone width No sinus pathology No history of sinusitis No relative contraindications No parafunction on RPD transition No sinus membrane perforation Subantral option 3: Sinus graft with immediate or delayed endosteal implant placement Carl E.Misch; Contemporary implant dentistry

69. Delayed implant placement > 5mm bone height (D4) < 6mm bone width Treated sinus pathology History of sinusitis Relative contraindications Parafunction on RPD transitional Sinus membrane perforation during surgery Subantral option 3: Sinus graft with immediate or delayed endosteal implant placement Carl E.Misch; Contemporary implant dentistry

70. Implant placed 4 months after graft Rate of healing can be assessed Decreased risk of losing the graft and implant if Postoperative sinus graft infection Implant in middle of graft doesn’t provide a source of blood vessels. Bone width augmentation along with sinus graft – larger implants- delayed technique Bone denser in sinus graft – delayed placement Carl E.Misch; Contemporary implant dentistry

71. Subantral option 4: sinus graft healing and extended delay of implant insertion < 5 mm bone present between residual crest and floor of the sinus Inadequate vertical bone and less recipient bone to act as vascular bed for graft. Larger antrum and minimal host bone

72. Better surgical access – antrum closer to crest Medial wall of sinus elevated at least 16 mm Augmented bone matures for 6-10 months before rentry for placement of endosteal implants. Implant surgery at re entry – periosteal flap on lateral side elevated Subantral option 4: sinus graft healing and extended delay of implant insertion Carl E.Misch; Contemporary implant dentistry

73. A muco-periosteal flap is elevated The site for implant is accomplished initially with a special, 3mm long, pilot drill. DOTT. COSCI FERDINANDO, 1994 DOTT. COSCI FERDINANDO, 1994, www.sinuslift.com

74. A special, 3mm. long, intermediate drill is usednow to prepare the site for the lifting drill A lifting drill is inserted as long as the actual height of the ridge measured on the x-Ray DOTT. COSCI FERDINANDO, 1994, www.sinuslift.com

75. Probing the site can confirm the integrity of the Schneider membrane. Trephine is used to collect some autologous bone for the graft The grafting material is prepared and pushed up into the implant site with the body lifting DOTT. COSCI FERDINANDO, 1994, www.sinuslift.com

76. The Radiograph confirms the membrane lift Consequential fillings are then performed till the desired lifting DOTT. COSCI FERDINANDO, 1994, www.sinuslift.com

77. Insertion of the screw implant DOTT. COSCI FERDINANDO, 1994, www.sinuslift.com

78. Sinus lift balloon Straight – 3.5mm Micro mini – 1.9mm Angled – 3.5 mm

79. Sinus lift balloon Atraumatic sinus membrane elevations. Lifts the Schneiderian membrane gently and uniformly- reduces perforation Volume of graft material required - direct proportion to the amount of fluid used to inflate the balloon. 1cc of fluid corresponds with 1cc of graft material. Traditional procedures result in 2-3mm of sinus height lift With 1cc of saline the Sinus Lift Balloon’s expected sinus elevation is 6mm

80. The Zimmer Sinus Lift Balloon procedure provides even pressured elevation of the Schneiderian membrane

81. conclusion Implant rehabilitation of the edentulous maxilla is one of the most challenging endeavours facing the restorative dentist. Comprehensive evaluation and precise evaluation of the patients needs, followed by appropriate treatment planning provide the restorative dentist with the platform to satisfy patient expectations

82. References Carl E Misch, Contemporary implant dentistry, Second edition, Mosby publications, 193-206 Michael S Block , John Kent , Luis Guerra, Implants in dentistry, W B Saunders company, 206-222 Fouad khoury; Bone augmentation in oral implantology. Quintessence books. 321-339

83. Jivraj ; Treatment Planning In Edentulous Maxilla; British Dental Journal, 2006, Vol 206, Sep, 261-279 Steven ; Implant retained maxillary overdentures, dent clin n am (48) 2004, 585-601

84. References Georgios Tasoulis; The Maxillary Sinus: Challenges and Treatments for Implant Placement, The Compendium of Continuing Education in Dentistry . Summers RB. The osteotome technique, Compend Contin Educ Dent. 1994;15(6):698-710 Nkenke , Microscopic analysis of bone remodelling after installation of implants using osteotome technique, Clin. Oral Implants Res 2002; 13:592-602

85. References www.sinuslift.com zimmerdental.com