8. • Indications
– Alveolar bone height less than 10mm
– Systemic health
– Condition of the remaining dentition
– Likelihood of a beneficial outcome
Appropriate patient selection
Careful Evaluation of the anatomy
Identification and management of any pathology
Sound surgical procedures
Appropriate post-surgical management
TREATMENT
SUCCESS
9. • Contraindications
– Local factors
• Tumors or pathologic growth in the sinus
• Severe chronic sinusitis
• Surgical scar/ deformity of sinus cavity
• Dental infection involving or in proximity to sinus
• Severe allergic rhinitis/ sinusitis
• Chronic topical steroid use
– Systemic Factors
• Radiation therapy involving maxillary sinus
• Metabolic disease
• Excessive tobacco use
• Drug/ Alcohol abuse
• Psychologic / Mental Impairment
12. Presurgical Evaluation of Maxillary sinus
• Radiographic techniques
– Panoramic projections
– CT or (CBCT) Cone beam computed tomography
– Look for any Masses, Pathology or Septa…also for any
major vessels in the lateral wall
13. DENTASCAN
• Specialised CT study
• CT image is interpreted by the
software (GE Systems)
• 1mm sections
• Volume and density
measurements
17. • Less than 10 mm….greater than 7mm
• Idea:
– Compresses the bone internally against the floor of the
sinus…Controlled inward fracture.
• Initial osteotomy site prepared…approx 2-3mm short of floor
of maxillary sinus
• Osteotomes…controlled compressive forces...gradually
adding incremental quantities of the bone graft
material...until fracture
18. • How much increase bone height…2-7mm ( 3.8mm
average )
• Crestal approach…approx 4mm
• If more bone … lateral wall approach may be more
advantageous
• Contraindicated in:
– Acutely sloped sinuses
– Septa in the location of the planned osteotomy
19.
20.
21.
22.
23. Clinician comments:
• Clin Perspective 1:
– Repeated tapping of the osteotomes with a mallet….
• Bothersome …..those not sedated
• Thick cortical bone
• Clin Perspective 2:
– Alignment of the osteotome
– Open wide …wide… wider please!!!
– Offset osteotomes
25. • Disturbance of blood supply is restricted to a minimum
• Sufficient coverage of the surgical wound is ensured.
– Incision ….on top of the alveolar ridge, or slightly on the
palatal side, through the keratinized, attached mucosa.
– This way the wound closure can be solid and with
sufficient overlap to deal with a possible dehiscency.
Flap design
26. • Preparation of the door be a threat to the neuro-vascular
bundle
• Possibility of mechanical damage by the wound retractor
• There is no reason for such high preparations
– There is no need for such a high ‘‘door’’.
• Door being too large for the width of the sinus,
making it impossible to raise it to a horizontal level.
– This problem may also be encountered with the
combination of ‘‘normal’’ sized doors and very narrow
sinuses.
Orbital Foramen
27. • Shape of the door should ideally follow the inner shape of
the maxillary sinus which usually is curved.
– Pre-op planning with OPG, CT or CBCT
– Clinical aspect of the lateral sinus wall will provide
information of the extent of the maxillary sinus.
• In most patients the lateral sinus wall is quite thin
and looks greyish-blue showing the circumference of
the sinus
• The rounded corners have also the surgical
advantage of a reduced chance of damaging the
Schneiderian membrane.
Sinus Floor
28. Lateral sinus wall preparation
• 2 methods…
– Cut out a window and push it in
– Thin the superficial bone and reach the membrane
• To thin out ..
– Start..Large carbide bur
– Finish Large diamond bur
• The healthy membrane will look dark greyish-blue. In
smokers the Schneiderian membrane may look
atrophic and be extremely thin and fragile to touch
29. • Chronic sinusitis is recognized by a thick, spongy
Schneiderian membrane…..
– Contraindicated
– Radiographic assessments ….
• Allergic conditions may also lead to chronical reactive
mucosa changes and can therefore also form a contra-
indication.
30.
31. Door Luxation
• Best performed with finger pressure…
• Not only can the surgeon feel the resistance and the
fracture of the door hinge, but also it will prevent any sharp
instrument from perforating the sinus mucosa.
• The aim is to bring the trapdoor in a horizontal position.
32. The Schneiderian Membrane
• The normal anatomy of the sinus will allow the door to turn
in an up-into horizontal position, however, only if the
Schneiderian membrane is sufficiently lifted.
• Special instruments… Tatum
• Start at the caudal edge slowly and carefully working
towards the mesial and distal sides of the sinus
• Only when the whole caudal membrane is prepared free
from the sinus bottom can the door be lifted
33. • The door will more or less remain in that position showing
that all mucosa-tissue is lifted to that level up to the medial
part of the sinus.
• Filling of the Graft material…
– Overfilling will cause necrosis of the membrane…loss of
the graft into the sinus
– Tidwell et al. 1992;
– Raghoebar et al. 1997;
– Timmenga et al. 1997
34. Dental root shaped configurations, that makes preparation of the
mucosa difficult.
35. It can be even more difficult at
longitudinal rims sinus floor
convolutions and root tip
expressions.
Luxating the Schneiderian
membrane from septa can be
difficult
36. • Previous sinus surgeries..
– Scar tissue impedes the separation of the membrane.
• When the alveolar bone is totally absent in some places
(due to resorption or traumatic bone loss after tooth
extractions, e.g. sinus perforation) the sinus mucosa can be
in immediate contact with the oral mucosa
– Schneiderian membrane cannot be kept intact.
• May lead to large perforations at very difficult sites,
making further preparation impossible.
38. Schneiderian Membrane Perforations
• Frequent, threaten coverage of graft
• Most likely to happen at sharp edges and ridges
– Small
• Where the elevated mucosa folds together when
lifting the door there is no need for further
measurements.
– Larger and located in an unfavorable area
• The perforation needs to be closed and covered in
order to prevent loss of the graft.
• Covering the defect with a resorbable membrane.
39. • Quite Large…………..Mission Aborted !!!
• Re-entry might be considered: 6 to 8 weeks later
(Chanavaz 1990).
40. Maxillary Sinus Septa
• Incidence - 16% and 58% ..
• Division into recesses…or may be complete….smaller
sinuses
• Carry the masticatory forces…dentate....thus lost in
edentulism
• Low septum… normal door preparation
• High septum….W shaped window…or 2 trap-doors
44. Haemorrhages
• Arterial Supply
• Hemorrhages during sinus grafting are rare,
– Main arteries are not within the surgical area.
– Minor bleed….stopped by slight gauze pressure.
– Electro-surgery will cause necrosis of the membrane
and therefore threaten the coverage of the graft
45. Bone Grafting, Bone healing and Remodeling
• Placement of graft…
• Healing and remodeling
– Vascularisation of the Schneiderian membrane and the
buccal mucoperiosteal flap and the bone segments of
the former sinus floor and the elevated lateral sinus wall.
– Save the bony trapdoor (Tatum 1986)
– Make cortical perforations in the inner aspect of the
former sinus bottom to create a bone-inductive stimulant
from the bone marrow
46. Primary alveolar bone height and width
• 4 mm of bone height of the original alveolar process for a
one stage procedure
Misch 1987; Watzek 1996; Ulm et al. 1995
• If Insufficient … 4 -6months later
• Width of the alveolar bone…. At least 5mm
Second stage procedure???
Insert the implant simultaneously
47. Implant following the Sinus Elevation
• Local anatomy after sinus floor elevation is normally very
favorable for implant surgery
• The ‘‘elevated’’ sinus floor normally allows implants with a
length of 12 mm.
53. Endoscopically Controlled Sinus floor Augmentation
Success with Sinus Augmentation : 75% - 93%
Jensen et al.1990
Tidwell et al. 1992
Morbidity compared to conventional is relatively high
Small et al.1993
Sinuscopy is routinely used as a diagnostic procedure
Pleiderer 1987
Fisher and Croft 1989
54.
55. • Potential Advantages:
– Excludes sinus pathology
– Low invasive
– Reduces risk of mucoperiosteal perforations
– Allows control of graft position
– Reduces the risk of Oro-antral fistula
56. After the Sinus surgery…..
• General Instructions…
• Midfacial Heaviness
• Sneezing
• Antihistaminics
• Nasal decongestants
57. • Safe technique with high predictability of success
Hirsch & Ericsson 1991;
Misch et al. 1991;
Smiler et al. 1992;
Raghoebar et al. 1993;
Betts & Miloro 1994;
Hürzeler et al. 1996
• Autogenous bone remains the material of choice currently
available for bone reconstructive procedures
Wood & Moore 1988;
Hirsch & Ericsson 1991;
Moy et al.1993
Sinus Augmentation: [Postscript]
60. • Greatest challenge in terms of regenerating bone for implant
placement
– Onlay block graft
– Particulate hydroxyapatite grafts
– Recent attempts have been with Guided Bone
regeneration
Failure due to
Resorption
61. Methods
• 4 Methods:
1. Osteoinduction By use of appropriate growth
factors
2. Osteoconduction…use of graft material that acts as
a scaffold
3. Distraction osteogenesis…surgically fractured
fragments are slowly pulled apart
4. Guided tissue regeneration…space is maintained to
be filled by new bone
70. Classification of Associated Complications
Type I : Mild to moderate bruising (Limited to chin)
Type II: Advanced bruising (Including neck)
Type III:Paresthesia of the mandibular dentition and/ or soft
tissues that recovers in two months
Type IV: Paresthesia of the mandibular dentition and/ or soft
tissues that does not recover in ≥ 6months
Type V: Facial deformities of muscle prolapsing of the chin
72. Outline
Anterior, Superior and the posterior cuts
Incision : Classical 3rd molar flap
Harvest : Similar to sagittal split
osteotomy
73. • The anterior cut:
– Made in the mandibular body,
• Inferior cut:
– From the distal of the first molar region. The length of the
cut is governed by the inferior alveolar nerve and the
dimensions of the required block.
• The posterior superior cut:
– Made on the lateral aspect of the ramus, perpendicular
to the external oblique osteotomy.
74.
75. • Complications
– Potential damage to the inferior alveolar nerve, limitation
of graft size and shape, which can be minimized by
adequate radiographic planning.
– Postoperative Trismus
– Potential damage to the lingual nerve during flap
incision.
• Suggested reference :
– D Brener. The mandibular ramus donor site. Australian Dental
Journal 2006;51:(2):187-190
76. Retromolar Area
Khouryet al. 1993; Raghoebar et
al. 1993;
Von Arxet al. 1996;
Misch 1997;
Schlegel et al.1998;
Khoury 1999;
Misch 1999;
Pikos 1999.
82. Anterior versus Posterior Approach
• Patients having anterior iliac surgery usually have a
noticeable postoperative limp, whereas those with posterior
iliac surgery have minimal limp, but may have difficulty
climbing stairs and rising from a chair.
• Most frequent complication from either approach is damage
to the cutaneous nerve supply.
• Blood loss is slightly greater in posterior surgery (200-
500cc).
93. • Involves gradual, controlled displacement of surgically
created fractures which results in simultaneous expansion of
soft tissue and bone volume.
• Gavriel Ilizarov, a Russian orthopedic surgeon,
– Credited with developing the armamentarium and
describing the biologic basis of this process for the
management of orthopedic limb deformities
94. Alveolar Distraction Osteogenesis
• Displacement of the osseous segment results in positioning
of a healthy portion of bone into a previously deficient site
• Expansion of the soft tissue adjacent the bone segment
• Original location fills by bone
• Filling with bone instead of fibrous tissue is a function of
the surrounding, healthy cancellous bone walls and location
within the skeletal functional matrix
95. • Growth phenomena …..determined by continuous tension
inside the tissues that precipitates a growth in the volume
and number of cells.
• This process ends when the push is exhausted and the cells
have occupied all the space genetically allocated to them.
• Fracture:
– Inflammatory process that is elicited leads to tissue
repair through an intramembranous ossification process
which terminates with the formation of new bone tissue.
97. • Osteotomy limited to the cortical bone, far from the nutritive
artery, and without stripping the bone.
• Continuous stretching force on the two bone segments
through the use of a device triggers the conditions for
growth.
• The undifferentiated cells in the bone marrow, not disturbed
by the corticotomy, evolve into osteoblasts and begin
formation of interlaced bone tissue
• As the separation progresses, the new bone lamellae are
orientated into parallel lines, and the regenerated tissue
becomes visible radiographically.
98. Only 6 mm of Alveolar bone existed above the inferior alveolar nerve
Horizontal and Vertical Osteotomies were completed before the device fixation
107. Transpositioning of Nerves
• Indications
–Replacing removable prosthetic appliances and
stabilizing the anterior residual dentition
–Stabilizing the temporomandibular joint and muscle
balance or tone overall, as there is reconstruction of the
total stomatognathic system
–Reducing alveolar ridge atrophy, as these procedures are
prophylactic or preventive in nature
108. • Limiting Factors
– Difficult surgical procedure…cautious and careful in
attempting it
– Risk of Nerve damage is real….Pt should be well
informed about the chance nerve deficit…or permanent
nerve damage.
– Risk of fracture of mandible …though minimal , is real
“Not Unlikely to have 3 to 4 rounds of consultations prior to
initiation of the treatment.”
110. • Safe distance of 6mm anterior to mental foramen be
maintained
• Regular radiographs
– OPG
– lat Cephalogram
– IOPA
– Occlusal
Will Not define Medial-
Lateral position of the IAN
Only the Sup- Inferior
position
116. Window created in the middle third
of the vertical residual height of
the mandible
Window too far superiorly …
Ant border :3-4mm distal to the
mental foramen
Should extend 4-6mm distal to
most distal implant position
117. • Boyne & James 1980
– Blade Implant ….Caldwell luc procdures
• 1996 Consensus Conference on Maxillary Sinus Bone
Grafting
Expose the Nerve with Hand instruments
118. • Boyne & James 1980
– Blade Implant ….Caldwell luc procdures
• 1996 Consensus Conference on Maxillary Sinus Bone
Grafting
Specially Designed
Nerve retractor or
nerve hook
Neuroelastic band
type of retractor
119. • While making the osteotomies…
– Apical end of the preparation is inferior to osteotomy site
– Implants are then placed
– Nerve is repositioned over the lateral aspect of the
implants
125. • Proper Implant position is mandatory for optimal function and
esthetics
– The “GUIDE” system
• Wax up models
• Radiographs
• Surgeon’s clinical experience
127. Computer Assisted Implant Surgery
• Most sophisticated and most promising
• Reduce surgical time
• Reduce surgical invasiveness
• More accurate transfer of treatment planning to actual
treatment procedure
128. Uses and Requirements
• Precision……avoid damage to important anatomical
structures
• Precise and continuous coordination of the patient
• Image Data-3D Imaging
• Surgical instrumentation
129. Sequence of Steps
1. Data Acquisition
2. Identification
3. Registration
4. Navigation
5. Accuracy
6. Feedback
130. Preoperative Data Acquisition
• Computed Tomography
– Accuracy
– Radiation
– CBCT & Spiral CT.....Dose reduction down to panoramic
radiography!!!
– Use of identifiable markers
• Anatomic markers: teeth
• Specific bony landmarks
• Artificial markers (Fiducial)
131. Identification & Registration
• Data interpreted by a software as anatomic geometric
element
– Touch pointer
– Ultrasound probe
• Accuracy is less but continuous data recording
• Registration:
– Matching between the geometry of the data and the
anatomical structures
132. 5 Registration methods:
1. Point-based
– Finding of triangles…equilateral tripods
– Hough transformation...intuitive algorithm
2. Line / Curve based
3. Surface based
4. Volume based
5. Projective methods
133. Navigation and Position Tracking
• Accuracy standards: 1mm per cubic meter
• GPS system
– Mechanical Tracking System
• Six axis coding robot with a passive arm
• Uses multiple markers
• Less desirable
134. • Magnetic Tracking System
– Uses a magnetic source and a field receiver
– Inaccuracies due to magnetic interferences
– Impractical
• Optical Tracking System
– Intersecting the vision plane between two and three
cameras to locate the markers with stereovision
– Passive arm: Absorbs & processes the light
– Active arm: Interprets the light
– Use of IRED…
– Operatory lighting is important
135.
136.
137. External Viewer & Augmented Reality
• Visualization of the instrument movement relative to image
data…….on the External Monitor
• Or….Image projection in the visual field of the surgeon
using a head mounted projection system
• Side Viewer Vs See-through viewer
138. • AUGMENTED REALITY VIEWER:
– Allows the surgeon to see the target data in 3
dimensions superimposed over the surgical site through
projected images in both eyes
• Allows the surgeon to adapt to the system more naturally
and rapidly
• Relative stability of the headset is critical to maintaining
accuracy
139.
140. – Benefits:
1. CAIS results in improved accuracy & Safety
2. Security features….stopping of drill rotation
3. Simulation before surgery
4. Implant position and planning
5. Real-time information
6. Surgical time reduced because of surgical guide
7. Non invasive or Flapless procedure.
Advantages and Disadvantages
141. • Limitations
– Initial Cost of the system
– Increased installation time for surgery
– Training is mandatory
– Accuracy subject to the system components
– Inaccurate data……
143. References
1. Carranza’s Clinical Periodontology 9th & 10th Edition
2. Clinical Periodontology and Implant Dentistry -Jan Lindhe
4th edition
3. Advanced Osseointegration Surgery: Application in the
Maxillofacial region- Branemark
4. Autogenous bone harvesting: A chin graft technique for
particulate and monocortical bone blocks-Dennis hunt &
Sascha Jovanovic
5. Anaomic aspects of Sinus floor Elevations - Johan P. A. van
den Bergh, Clin Oral Impl Res 2000: 11: 256–265
6. Sinus Lift Procedure of the Maxilla in Patients with
Inadequate Bone for Dental Implants: Radiographic
Appearance- James J. Abrahams, AJR:174, May 2000
144. 7. www.NYEE.edu -Caldwell-Luc Procedure: Operative
Technique –
8. www.norwalkradiology.com
9. www.bocaradiology.com
10. Iliac Crest Autogenous Bone Grafting: Donor Site
Complications - John Gray Seiler
11. Nkenke E. Morbidity of harvesting of retromolar bone grafts:
a prospective study Clin. Oral Impl. Res, 13, 2002; 514–521
12. Wagner A.Computer-aided placement of endosseous oral
implants in patients after ablative tumour surgery: assessment
of accuracy Clin. Oral Impl. Res. 14, 2003: 340–348
