Basic Surgical Techniques for Endosseous Implant Placement

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Basic Surgical Techniques for
Endosseous Implant Placement
Division of Oral and Maxillofacial Surgery
University of Minnesota
WHAT IS A DENTAL IMPLANT?
 Dental implant is
an artificial titanium
fixture
which is placed
surgically into the
jaw bone to
substitute for a missing
tooth and its root(s).
History of Dental Implants
In 1952, Professor Per-Ingvar Branemark,
a Swedish surgeon, while conducting research
into the healing patterns of bone tissue, accidentally
discovered that when pure titanium comes into
direct contact with the living bone tissue, the two
literally grow together to form a permanent
biological adhesion. He named this phenomenon
"osseointegration".
First Implant Design by Branemark
All current implant
designs are
modifications of this
initial design
Surgical Procedure
STEP 1: INITIAL SURGERY
STEP 2: OSSEOINTEGRATION PERIOD
STEP 3: ABUTMENT CONNECTION
STEP 4: FINAL PROSTHETIC
RESTORATION
Fibro-osseous integration
• Fibroosseous integration
– “tissue to implant contact with dense collagenous
tissue between the implant and bone”
• Seen in earlier implant systems.
• Initially good success rates but extremely
poor long term success.
• Considered a “failure” by todays standards
Osseointegration
•
•
Success Rates >90%
Histologic definition
– “direct connection between living bone and loadbearing endosseous implants at the light
microscopic level.”
•
4 factors that influence:
Biocompatible material
Implant adapted to prepared site
Atraumatic surgery
Undisturbed healing phase
Soft-tissue to implant interface
• Successful implants have an
– Unbroken, perimucosal seal between the soft
tissue and the implant abutment surface.
• Connect similarly to natural teeth-some
differences.
– Epithelium attaches to surface of titanium much
like a natural tooth through a basal lamina and the
formation of hemidesmosomes.
Soft-tissue to implant interface
• Connection differs at the connective tissue
level.
• Natural tooth Sharpies fibers extent from the
bundle bone of the lamina dura and insert into
the cementum of the tooth root surface
• Implant: No Cementum or Fiber insertion.
Hence the Epithelial surface attachment is
IMPORTANT
Subperiosteal
Transmandibular Implant
Blade Implant
Endosteal Implants
The “Parts”
• Implant body-fixture
• Abutment (gingival/temporary healing vs.
final)
• Prosthetics
Clinical Components
abutment
Team Approach
• A surgical – prosthodontic consultation is
done prior to implant placement to address:
–
–
–
–
soft-tissue management
surgical sequence
healing time
need for ridge and soft-tissue augmentation
Clinical Assessment
• Assess the CC and Expectations
• Review all restorative options:
– Risks and Benefits
• Select option that meets functional and
esthetic requirements
Patient Evaluation
• Medical history
–
–
–
–
–
vascular disease
immunodeficiency
diabetes mellitus
tobacco use
bisphosphonate use
History of Implant Site
•
Factors regarding loss of tooth being replaced
– When?
– How?
– Why?
•
Factors that may affect hard and soft tissues:
– Traumatic injuries
– Failed endodontic procedures
– Periodontal disease
•
Clinical exam may identify ridge deficiencies
Surgical Phase- Treatment Planning
• Evaluation of Implant Site
• Radiographic Evaluation
• Bone Height, Bone Width and Anatomic
considerations
Basic Principles
• Soft/ hard tissue graft bed
• Existing occlusion/ dentition
• Simultaneous vs. delayed reconstruction
Smile Line
• One of the most influencing factors of any
prosthodontic restoration
• If no gingival shows then the soft tissue
quality, quantity and contours are less
important
• Patient counseling on treatment
expectations is critical
Anatomic Considerations
•
•
•
•
•
•
Ridge relationship
Attached tissue
Interarch clearance
Inferior alveolar nerve
Maxillary sinus
Floor of nose
Radiological/Imaging Studies
•
•
•
•
Periapical radiographs
Panoramic radiograph
Site specific tomograms
CAT scan (Denta-scan, cone beam CT)
Width of Space and Diameter of Implant
Attention must be paid to both the coronal and
interradicular spaces
A case against routine CT
• Expense
• Time consuming process
• Use of radiographic template/proper fit
requires DDS present
• Contemporary panoramic units have
tomographic capabilities
• Usually adds no additional data over
standard database
Image Distortion
Anatomic Limitations
Buccal Plate
Lingual Plate
Maxillary Sinus
Nasal Cavity
Incisive canal
Interimplant distance
Inferior alveolar canal
Mental nerve
Inferior border
Adjacent to natural tooth
0.5mm
1.0 mm
1.0 mm
1.0mm
Avoid
1-1.5mm
2.0mm
5mm from foramen
1 mm
0.5mm
Dental Implant Surgery Phase I
• Aseptic technique
• Minimal heat generation
– slow sharp drills
– internal irrigation?
– external cooling
Dental Implant Surgery Phase I
• Adequate time for integration
• Adequate recipient site
– soft tissue
– bone
• Kind & Gentle technique
Disposition
1. Chlorhexidine
2. Analgesics
+/- antibiotics
Implant placement 3 months after menton bone
grafting
Exposure of Implant during
Placement
Summer’s Osteotomes
Limitations to Implant placement in the
Maxilla
• Ridge width
• Ridge height
• Bone quality
Surgical Solutions to Anatomical
Limitations
Onlay Bone Graft
Sinus Lift
Summers, RB. A New concept in Maxillary
Implant Surgery: The Osteotome technique.
Compendium. 15(2): 152, 154-6
• Ridge expansion technique
– 3-4 mm of crestal alveolar width
required
• Sinus floor elevation technique
– 8-9 mm of alveolar bone height
required in order to place a 13 mm
implant
(4-5 mm sinus floor elevation)
Introduction
Ridge expansion technique
• 1.6 mm pilot hole
• Summers osteotome # 1-4
– sequenced tapered osteotomes.
– ridge expansion (displacement) versus
bone removal.
• Final drill coincident with the final
implant size (sometimes not
necessary)
Introduction
Sinus floor elevation technique
• 1.6 mm pilot hole
• Summers osteotome # 1-4
– Sinus floor microfractured superiorly
– Sinus floor can be elevated 4-5 mm
– May backfill with bone allograft/alloplast
• Final drill coincident with final
implant size
Surgical Technique
A. Rake, K. Andreasen, S. Rake, J. Swift A Retrospective
Analysis of Osteointegration in the Maxilla Utilizing an
Osteotome Technique versus a Sequential Drilling
Technique, 1999 AAOMS Abstract
• 155 maxillary implants in 84 patients restored
for at least 6 months
– 57 were placed utilizing the osteotome technique
– 98 were placed utilizing the drilling technique
• One implant failed of the 98 in the drill group
• None of the implants had failed of the 57 in the
osteotome group
Stage II Surgery Preoperative
Considerations
• 3-6 months after stage I
Stage II Surgery Preoperative
Considerations
• Done under local anesthesia
• Pre-op medications
– Chlorhexidine rinse
Placement of
healing abutment
conclusions
• The failing implant is very difficult to treat
• Traumatic surgical manipulation with
initial instability of implant increases risk
of failure
• Implant success is only as good as the
prosthodontic reconstruction
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