1. IMPLANT PROTOTYPES
DESIGNS AND SYSTEMS
(How to select an implant system)
Objectives
Participants will understand the rationale behind the design of the root form implant. They will
be given an over view of the other types of Implant systems. Nobel Replace® and Nobel Active ®
designs will be discussed in some detail. At the end of the course they will be in a position to
select an implant and a system on a scientific basis.
DEFINITION :
A Dental Implant is defined as “ A substance that is placed into the jaw to support a
crown or fixed or removable denture.”
History
ANCIENT IMPLANTS :-
Ú 16 th Dark stone
( Egyptian-South American)
Ú 17 th Carved ivory teeth
EARLY IMPLANTS :-
Ú 1809 Gold implant
Ú e.20th Lead, iridium, tantalum,
stainless steel, & cobalt alloy
Ú 1913 hollow basket, iridium + gold wires
EARLY IMPLANTS
Ú 1937 Adams’s submergible threaded
cylindrical implant with round bottom
Ú 1938 Strock’s (long term) threaded vitallium
implant (cobalt+chrome+molybdenum)
Ú The modern implants appear to be variants or composites of some of the designs of early
implants
2. DENTAL IMPLANT DESIGNS
Endosteal Implants Root/Blade
Subperiosteal Implants
Transosteal Implants
Intramucosal implants
Dental Implant Designs
Endosteal Implants Root /Blade
Subperiosteal Implants
Transosteal Implants
Intramucosal implants
AN ENDOSTEAL IMPLANT
IS PLACED DIRECTLY INTO THE BONE, LIKE NATURAL TOOTH ROOTS AND CAN BE USED FOR
MANY PURPOSES. A SINGLE PIN CAN BE INSERTED THROUGH AN EXISTING TOOTH TO
STRENGTHEN AND STABILIZE IT. OTHER STYLES CAN PROVIDE AN ANCHOR FOR ONE OR MORE
ARTIFICIAL TEETH.
Root Form Dental Implants
Solid Tapering types
Solid cylinder
Pin types
Screw shaped implant type
Hollow cylinder design
Basket design
Solid Tapering types
Solid cylinder
Pin types
Screw shaped implant type
Basket design/BOI
4. BLADE IMPLANT
IT IS A BLADE PLACED DIRECTLY INTO BONE AND MAY BE SOLID OR VENTED. IT MAY BE USED TO
SUPPORT SINGLE OR MULTIPLE TEETH. IT USES THE CONCE
SUBPERIOSTEAL IMPLANT:
IS USED WHEN THE BONE HAS ATROPHIED AND JAW STRUCTURE IS LIMITED. THE
LIGHTWEIGHT, INDIVIDUALLY
BONE, PROVIDING THE EQUIVALENT OF MULTIPLE TOOTH ROOTS. IT MAY BE USED I
AREA OR, IF ALL THE TEETH ARE MISSING IN THE ENTIRE MOUTH
Subperiosteal Implants
IT IS A BLADE PLACED DIRECTLY INTO BONE AND MAY BE SOLID OR VENTED. IT MAY BE USED TO
MULTIPLE TEETH. IT USES THE CONCEPT OF ‘FIBROOSSEOUS’ INTEGRATION
SUBPERIOSTEAL IMPLANT:
IS USED WHEN THE BONE HAS ATROPHIED AND JAW STRUCTURE IS LIMITED. THE
LIGHTWEIGHT, INDIVIDUALLY-DESIGNED, METAL FRAMEWORK FITS OVER THE REMAINING
BONE, PROVIDING THE EQUIVALENT OF MULTIPLE TOOTH ROOTS. IT MAY BE USED I
AREA OR, IF ALL THE TEETH ARE MISSING IN THE ENTIRE MOUTH.
IT IS A BLADE PLACED DIRECTLY INTO BONE AND MAY BE SOLID OR VENTED. IT MAY BE USED TO
PT OF ‘FIBROOSSEOUS’ INTEGRATION
IS USED WHEN THE BONE HAS ATROPHIED AND JAW STRUCTURE IS LIMITED. THE
DESIGNED, METAL FRAMEWORK FITS OVER THE REMAINING
BONE, PROVIDING THE EQUIVALENT OF MULTIPLE TOOTH ROOTS. IT MAY BE USED IN A LIMITED
5. A Letter to the editor BDJ
Sir,
A 74-year-old patient was referred to the oral surgery department by her general dental
practitioner. On consultation, the patient complained of a loose lower complete denture. She
reported that she had undergone implant placement some 20 years previously in South Africa
and that she had not attended for dental examination since.
Clinical and radiographic examination revealed a subperiosteal mandibular implant (Figs 1,2).
The bar was firm and the patient reported that she was experiencing no pain. There were
multiple mucosal dehiscences anteriorly and posteriorly, with the exposure of necrotic bone.
There appeared to be some deposits of calculus associated with the abutments.
.
Note dehiscences with bone exposure posteriorly, exposure of a screw in the lower left anterior
region and calculus deposits around the posts
Note radiolucencies adjacent to the anterior screws. The generalised lack of close fit to bony
surface is likely related to continued ridge resorption
Radiographic examination showed a metal framework spanning the entire edentulous mandible.
It sat approximately 2-2.5 mm above the alveolar ridge. Due to the smooth bony border and the
even loss across the mandible, this is most likely to be due to continued resorption over time
rather than pathological bone loss due to infection. The framework was secured to the bone by
four retaining screws: two anteriorly and two posteriorly. The mandible itself was atrophic, with
radiolucencies evident around the two anterior retaining screws.
6. Complete subperiosteal implant placement was first described as a treatment for the atrophic
mandible in the 1940s. A mucoperiosteal flap would be raised to allow an impression to be
made of the surface of the mandible. CT scans were also used to allow CAD/CAM fabrication of
the framework, negating the need for impressions. The framework usually rests on the
mandible, with no penetration into the bone.
Due to the high success rates in atrophic mandibles of osseointegrated implants facilitated by
the placement of autogenous grafts, subperiosteal implants are no longer used. However, as this
case highlights, there may still be some in situwhich could present to the general dental
practitioner.
Manchester
TRANSOSSTEAL IMPLANTS
Transosteal or transosseous dental implants are implants composed of a metal plate and
transosteal pins or posts. The metal plate is held with retentive pins or screws fixed to the
inferior border of the mandible. This metal plate supports the transosteal pins/posts that
penetrate the full thickness of the mandible and project into the mouth in the inter-foraminal
area.
The transosseous dental implants used in humans are the ‘staple bone implant’ system and the
‘transmandibular implant’ system (TMI).
Transosteal Implants
7. INTRAMUCOSAL INSERTS
REPRESENT A FOURTH TYPE OF IMPLANT USED WITH REMOVABLE DENTURES. THE
MUSHROOM-SHAPED INSERTS ATTACH TO THE GUM-SIDE OF THE DENTURE AND FIT INTO
SPECIALLY PREPARED INDENTIONS IN THE ROOF OF THE MOUTH. THEY PROVIDE GREATLY
INCREASED STABILITY AND HOLDING POWER.
Intramucosal implants
8. Implant BioMaterials
A. Metals and Alloys
B. Inert ceramics
C. Ca phosphate ceramics
D. Bioactive and biodegradable ceramics
E. Polymers
Metals and alloys
Titanium (Pure) 100% Cp Titanium
Titanium alloy Titanium 90%
Chromium 2%
Molybedenium 7%
Zirconium
Chromium cobalt Cobalt 66%
alloy Chromium 37%
Molybedenium 7%
Stainless Steel Iron 70%
Chromium 18%
Nickel12%
Tantalum / Gold/ Platinium
Inert Ceramics
Aluminium oxide Al2O3
i. Polycrystalline
ii. Single crystal
Zirconium oxide ZrO2
Zircona
9. Titanium Oxide TiO2
ENGINEERING PROPERTIES OF METALS AND ALLOYS USED FOR SURGICAL IMPLANTS
Material Nominal Modulus of Ultimate Elongation Surface
Analysis(w/o) Elasticity Tensile to Fracture(%)
GN/m(psi x 10) MN/m(ksi)
Titanium 99+Ti 97(14) 240-550(25-70) >15 Ti oxide
Ti Al 90Ti-6Al-4V 117(17) 869-896(125-130) >12 Ti oxide
vanadium
Co CrMo- 66Co-27Cr-7Mo 235(34) 655(95) >8 Cr oxide
(casting)
Stainless steel 70Fe-18Cr-12Ni 193(28) 480-1000 >30 Cr oxide
(316L) (70-145)
Zirconium 99+Zr 97(14) 552(80) 20 Zr oxide
Tantalum 99+Ta - 690(100) 11 Ta oxide
Gold 99+Au 97(14) 207-310(30-45) >30 Au
Platinum 99+Pt 166(24) 131(19) 40 Pt
IMPLANT DESIGN
11. Smooth vs Rough/Threaded
Cylinder vs Flare
Platform switch vs Platform shift
Smooth vs Rough/Threaded
Platform switch vs Platform shift
12. Crestal Module design
INTERNAL vs EXTERNAL HEX vs TRI LOBE
Precision fit
Crestal Module design
Smooth vs. Rough/Threaded
INTERNAL vs EXTERNAL HEX vs TRI LOBE
Smooth vs. Rough/Threaded
13. Crestal Module design
Cylinder vs. Flare
Crestal Module design
Platform switch vs shift
When platform switching, a narrower abutment diameter for a given implant platform diameter
is used; for example, placing a 3.8
However when the implant system provides for a NEP abutment then a
Astra, Ankylos, or Bicon.
1) Esthetics. .
2) Implant Placement Flexibility
Platform switch/shift
, a narrower abutment diameter for a given implant platform diameter
is used; for example, placing a 3.8 mm-wide abutment on a 4.8 mm-wide implant. Osstem
plant system provides for a NEP abutment then a platform shift
2) Implant Placement Flexibility.
, a narrower abutment diameter for a given implant platform diameter
wide implant. Osstem
platform shift is done.
14. Implant Body Design
Cylinder vs tapered threaded
Thread shapes-V thread/buttress/r
Thread geometry shape/pitch/depth
Surface preparation-Ti plasma spray coating, sand blasting surface etching, acid etching, laser
induced etching, HA coating , Ti Unite™, SLA® surface
Flat /grooved areas
Implant Body Design
Implant Body design
Thread Geometry Pitch/Shapes/Depth
IMPLANT SURFACE
Ti Plasma Spray Coating
Implant Body Design
Cylinder vs tapered threaded
V thread/buttress/reverse buttress/square thread.
Thread geometry shape/pitch/depth
Ti plasma spray coating, sand blasting surface etching, acid etching, laser
induced etching, HA coating , Ti Unite™, SLA® surface
Thread Geometry Pitch/Shapes/Depth
Ti plasma spray coating, sand blasting surface etching, acid etching, laser
15. Sand blasting surface etching
Implant Body Surface Modification
ACID ETCHING
The acid etched dental implants were immersed in a mixture of HNO
surface treatment, the samples were rinsed with distilled water, dried in an air furnace at 70 ºC
for 2 h, packed and sterilized with gamma radiation (25 kgray).
IMPLANT SURFACE MODIFICATIONS
Laser induced etching/sintering
SEM image of ablated holes formed on a titanium surface with 0.5 ps pulses of a KrF excimer
laser. The laser fluence was 2.4 J/cm2 and 1000 shots were applied (Bereznai et al., 2003).
Implant Body Surface
H A COATING
Sand blasting surface etching
Implant Body Surface Modification
The acid etched dental implants were immersed in a mixture of HNO3, HCl and H
surface treatment, the samples were rinsed with distilled water, dried in an air furnace at 70 ºC
for 2 h, packed and sterilized with gamma radiation (25 kgray).
LANT SURFACE MODIFICATIONS
Laser induced etching/sintering
SEM image of ablated holes formed on a titanium surface with 0.5 ps pulses of a KrF excimer
laser. The laser fluence was 2.4 J/cm2 and 1000 shots were applied (Bereznai et al., 2003).
, HCl and H2SO4 After
surface treatment, the samples were rinsed with distilled water, dried in an air furnace at 70 ºC
SEM image of ablated holes formed on a titanium surface with 0.5 ps pulses of a KrF excimer
laser. The laser fluence was 2.4 J/cm2 and 1000 shots were applied (Bereznai et al., 2003).
16. HA coatings on dental implants have been shown to accelerate surface bone apposition,
shortening the waiting period for dental implant restoration.
HA surface known to degrade and in some instances separates
Implant Body Surface
Ti Unite™
TiUnite is titanium oxide rendered into an osseoconductive ceramic biomaterial through spark
anodization. Unlike implants with machined surfaces, TiUnite has clinically demonstrated the
ability to increase the predictability and speed at which dental implants osseointegrate through
osseoconductivity.
Implant Body Surface
SLA® surface
Surface roughening is achieved through large grit sand-blasting with corundum particles
followed by acid etching, commonly referred to as SLA® surface.
The SLActive® surface has less surface tension and increases hydrophilic properties (wetability)
intended to attract blood cells. SLActive® treated implants are stored and shipped in a vial filled
with an isotonic liquid (salt water) to preserve the reduced surface tension qualities of the
implant.
Implant Body Design
Cylinder vs tapered threaded
18. Prosthetic connection design for ease of use and to stabilise prosthetic
Standardized tapered drilling protocol
Groovy to enable faster bone formation
Coronal design to improve soft tissue support
Tapered body design for optimal initial stability
Triunite oxidised surface to enhance osseointegration
NobelReplace™ – Strong user benefits
Tri-channel internal connection
Color-coding
The implant of choice for Advanced Users
Prosthetic connection design for ease of use and to stabilise prosthetic restorations
Standardized tapered drilling protocol
Groovy to enable faster bone formation
Coronal design to improve soft tissue support
Tapered body design for optimal initial stability
Triunite oxidised surface to enhance osseointegration
Strong user benefits
channel internal connection
The implant of choice for Advanced Users: Treatment predictability/Safety
restorations
19. Ease-of-use, simplified drilling protocols, consistent restorative ou
stability allows the use of NobelReplace also in more demanding indications.
Clinical flexibility
Satisfies broad range of indication: from single tooth to fully edentulous restorations as well as
temporary solutions. Due to its
placement in extraction sites.
Suitable for NobelGuide
Prosthetic versatility
Tri-channel connection supports all types of restorative solutions including individualized
NobelProcera prosthetic sol
long term esthetics and functionality.
NobelReplace™ Tapered Groovy
TiUnite “all the way up”
• Strong and faster osseointegration than machined surface implants
Grooves on Threads
• Bone is formed more rapidly inside the groove
High stability
Grooves on Collar
• Intended for hard and soft tissue stabilization and improved long term esthetics
use, simplified drilling protocols, consistent restorative outcomes and optimal initial
stability allows the use of NobelReplace also in more demanding indications.
Satisfies broad range of indication: from single tooth to fully edentulous restorations as well as
temporary solutions. Due to its tapered design NobelReplace is also ideal for immediate
placement in extraction sites.
channel connection supports all types of restorative solutions including individualized
NobelProcera prosthetic solutions. It also secures accurate prosthetic positioning and provides
long term esthetics and functionality.
NobelReplace™ Tapered Groovy
osseointegration than machined surface implants
Bone is formed more rapidly inside the groove
for hard and soft tissue stabilization and improved long term esthetics
tcomes and optimal initial
Satisfies broad range of indication: from single tooth to fully edentulous restorations as well as
tapered design NobelReplace is also ideal for immediate
channel connection supports all types of restorative solutions including individualized
utions. It also secures accurate prosthetic positioning and provides
for hard and soft tissue stabilization and improved long term esthetics
20. Differences between
Replace™ Select Tapered and NobelReplace™ Tapered
Implant surface and grooves
Bone forms faster within the grooves, compared to implant surfaces without grooves
Resulting in higher implant stability2
Grooves on collar:designed
esthetics
1.Zechner et al. Clin Oral Implants Res 2003
SINGLE TOOTH RESTORATION
Young female, non-smoker, no parafunctional habit, persistent deciduous lateral incisor
Diagnosis
Extraction of persistent deciduous lateral incisor. Orthodontic treatment finalized. Missing lateral central
incisor, limited space to adjacent teeth.
Treatment
Insertion of a NobelReplace Tapered Groovy NP/13 mm implant,
intraoperative X-rays shows narrow space conditions, immediate loading with a temporary resin crown.
Replace™ Select Tapered and NobelReplace™ Tapered
surface and grooves – Osseointegration1
Bone forms faster within the grooves, compared to implant surfaces without grooves
Resulting in higher implant stability2
for hard and soft tissue stabilization and improved long term
Zechner et al. Clin Oral Implants Res 2003
SINGLE TOOTH RESTORATION
smoker, no parafunctional habit, persistent deciduous lateral incisor
Extraction of persistent deciduous lateral incisor. Orthodontic treatment finalized. Missing lateral central
incisor, limited space to adjacent teeth.
Insertion of a NobelReplace Tapered Groovy NP/13 mm implant,
shows narrow space conditions, immediate loading with a temporary resin crown.
Bone forms faster within the grooves, compared to implant surfaces without grooves
for hard and soft tissue stabilization and improved long term
smoker, no parafunctional habit, persistent deciduous lateral incisor
Extraction of persistent deciduous lateral incisor. Orthodontic treatment finalized. Missing lateral central
shows narrow space conditions, immediate loading with a temporary resin crown.
21. Treatment
Insertion of a NobelReplace Tapered Groovy NP/13 mm implant,
intraoperative X-rays shows narrow space conditions, immediate loading with a temporary resin crown.
Results
Excellent esthetics and soft tissue response shortly after final esthetic installed and after three years
Multiple teeth restoration
Young female, came to clinic because of trauma against central incisors
Treatment
Atraumatic extraction of central incisors. Flapless immediate implant placement 2 NobelReplace
Tapered Groovy, WP Platform Shifting.
Products used
2 NobelReplace Tapered WP
2 NobelProcera Zirconia Abutments
2 NobelProcera Alumina Crowns
Results
2 NobelProcera Alumina Crowns (Graft for soft tissue thickness).
NobelActive™ design
Insertion of a NobelReplace Tapered Groovy NP/13 mm implant,
rays shows narrow space conditions, immediate loading with a temporary resin crown.
Excellent esthetics and soft tissue response shortly after final esthetic installed and after three years
Young female, came to clinic because of trauma against central incisors
extraction of central incisors. Flapless immediate implant placement 2 NobelReplace
Tapered Groovy, WP Platform Shifting.
2 NobelReplace Tapered WP
2 NobelProcera Zirconia Abutments
2 NobelProcera Alumina Crowns
a Crowns (Graft for soft tissue thickness).
rays shows narrow space conditions, immediate loading with a temporary resin crown.
Excellent esthetics and soft tissue response shortly after final esthetic installed and after three years
extraction of central incisors. Flapless immediate implant placement 2 NobelReplace
22. • Expanding tapered body with double variable thread design and apical drilling blades.
• Manual insertion protocol
Benefits
• Gradual bone condensing and high initial
• Enables ”active” directional changes for optimal restorative position
NobelActive™ design
Features:
Triunite
groovy
Features
Expanding tapered body with double variable thread design and apical drilling blades.
Gradual bone condensing and high initial stability
Enables ”active” directional changes for optimal restorative position
Expanding tapered body with double variable thread design and apical drilling blades.
23. Benefits
• Documented to enhance osseointegration and increase of the predictability of implant
treatment1
• Bone forms faster within the grooves, compared to implant without grooves2
NobelActive™ design
Benefits
• Allows for maximum alveolar bone volume around implant for improved soft tissue support
Animation: Bone condensing
NobelActive™ design
Features:
APICAL:Drilling blades on apex.
BENEFITS:
24. Enable smaller osteotomy.
NobelActive™ design
Features
• Conical connection
• Built-in Platform Shifting
Benefits
• Sealed connection
• Increased mechanical strength
• Designed to enhance Soft Tissue Integration
• NOBEL ACTIVE DESIGN
• FEATURES:Hexagonal interlocking
• Benefits
25. • Secure reposition of prosthetic components
• Allows for prosthetic flexibility and implant level bridges
Dual-function prosthetic connection
NobelActive™
Macro Design Features
1. Coronal portion back taper (except 3,5)
• Maximizes the volume of alveolar bone around the implant
2. Constantly expanding central core
• Acts like a threaded osteotome
• Compacts the bone outward
• Provides excellent primary stability
3. Sharp blades, deep widely spaced 35º double lead threads
• Allows implant to condense through bone
• Actively changes direction
Titanium Abutment Fit Into Implant
26. Insertion Torque Discussion
Insertion torque requirements for different implant designs are not comparable.
The NobelActive implant requires higher insertion torque due to the large helix angle of the
thread
For each rotation, the implant advances 2.4 mm
Occlusal Forces and Implant Design
Stress and strain cause crestal bone loss and decrease long term survival of implant.
Force applied to dental implants may be characterised as
Force Magnitude
Force duration
Force Type
Force Direction
OCCLUSAL FORCES AND IMPLANT DESIGNS
Insertion Torque Discussion
e requirements for different implant designs are not comparable.
The NobelActive implant requires higher insertion torque due to the large helix angle of the
For each rotation, the implant advances 2.4 mm
Occlusal Forces and Implant Design
and strain cause crestal bone loss and decrease long term survival of implant.
Force applied to dental implants may be characterised as
OCCLUSAL FORCES AND IMPLANT DESIGNS
e requirements for different implant designs are not comparable.
The NobelActive implant requires higher insertion torque due to the large helix angle of the
and strain cause crestal bone loss and decrease long term survival of implant.
27. Force magnitude
Average forces of mastication vary from 10lb to 350lb
Molars 200lb Canine100lb Incisors 25-35lb
Parafunction as high as 1000lb
Occlusal Forces and Implant Design
Force Duration
Normally teeth are loaded during swallowing and eating which is less than 30 min /day
Bruxism increases duration to several hrs a day
Occlusal Forces and Implant Design
Force Type
Compression, tension and shear
Bone is strongest under compression ,35% weaker under tension and 65% weaker when loaded
in shear
Occlusal Forces and Implant Design
Force Direction
Implant that is angled receives increased amount of shear loads especially in the crestal region.
Angled implant will also receives more stress on the overall implant system with increased risk
of abutment screw loosening and and fatigue fractures of the implant or its components.
Occlusal Forces and Implant Design
Force Magnification
Occurs when the stress is increased beyond the usual conditions of load.
Cantilevered prosthesis
Crown height ratio greater than normal
Parafunction
IMPLANT SIZE AND DIAMETER
Short vs long implants: To obtain predictable success in situations with most patient force
factors or bone densities, there is minimum implant length, depending on the implant body
28. width and the implant design. After the ideal treatment plan determines the key implant
positions and implant number, the implant length selected for most treatment plan options is at
least 12 mm long.
Wide vs narrow implants :The logical method to increase functional surface area is to increase
the implant diameter , because the opposing landmarks limit the implant length. Wider root
form designs exhibit a greater area of bone contact than narrow implants of similar design, in
part from an increase in circumferential bone contact.
SHORT VS LONG IMPLANTS
DISADVANTAGES
Studies show success with implant lengths of at least 10-15mm in lengths
Implants 10mm and smaller had increased failure rates.( 10% vs 3%)
Failures of short implants occurred after prosthetic loading and especially in the posterior region
ADVANTAGES
Bone grafting not required to restore alveolar ht
Less risk of damage to adjacent structures and thermal insult during osteotomy
Surgical ease
IMPLANT SIZE:SHORT VS LONG
GUIDELINES
Increase diameter
Splint together
Decrease crown ht
Decrease cantilever
Increase surface area design
OD vs FPD
Minimise lateral forces
Improve bone density
29. WIDE VS NARROW IMPLANTS
ADVANTAGES
Surgical Rescue implant
Failed implant/immediate implant
Tooth extraction/immediate
Increased surface area
Compensate unfavourable patient force factors
Enhance surface for short implants
Compensate for poor bone density
Minimise loads for angled implants/cantilevers
DISADVANTAGES
Bone trauma because of extended drill sequence
Decreased facial thickness may lead to recession
Stress shielding
Increased surgical failure rate
Too close to adjacent tooth ,PDL encroachment
Selecting an Implant System
Training
Budget
Established company
Versatility of System
Mentorship
Warranty
30. THANK YOU
Suggested references:
Branemark PI,Hansson BO,Adell R, Briene U,Lindstorm J,Hallen O,et al.(1997).Osseoitegrated
implants in the treatment of the edentulous jaw,experience from a 10yr period.Scand J
Plast.Reconstr Surg 16:1-132
Goldberg NI,Gershkoff A (1949),The implant lower denture.Dental digest 55 :490-494
Subperiosteal implants,H Beddis,S Lello,J Cunliffe &P Coulthard BDJ 212,4(2012)Published
online:13jan 2012,doi;10.1038/sj;bdj:2012:6
Small IA, Misiek D(1986),Asixteen year evaluation of the mandibular staple bone plate.J. Oral
Maxillofac. Surg. 44:60-66
Dahl G,History of intramuscular inserts.J Oral Implantol 1991;17(4):440
Becker J, Ferrari D, Herten M, Kirsch A, Schaer A, Schwartz F, Influence of platform switching on
crestal bone changes at non submerged titanium implants :A histomorphometrical study in
dogs.J Clin Periodontal 2007;34:1089-1096.
Vigolo P, Givani A, Platform switched restorations on wide diameter implants;a 5yr clinical
prospective study.Int J Oral Maxillof Implants 2009;24:103-109.
Fickl S, Zuhr O, Stein JM, Hurzeler MB.Periimplant bone level around implants with platform
switched abutments .Int J Oral Maxillofac.implants 2010;25:577-581
Berenznai et al,2003, Glauser R , Zembic A, Rahstaller P,Windisch S.Five year results of implants
with an oxidized surface placed predominantly in soft quality bone and subjected to immediate
occlusal loading.J Prosthet.Dent.2007;97(suppl):559-568.
