SECTION 2 – THE EVOLUTION
OF IMPLANT DENTISTRY
DR.
NIZNICK SPEAKS OUT… on Selective Surfaces and Early Loading |
Q:
Somebody said awhile ago something about implant surfaces and tissue
responses. Basically the comment was, "rough is good for bone but bad
for soft tissues." Smooth is good for soft tissues but bad for bone.
I've seen that this may be true. Can somebody provide a physiological
explanation for that?
A:
When hard tissue grows into the irregularities of a rough surface, it
provides greater attachment strength, as measured by torque tests. This
may also be attributed to the greater surface area created by the rough
surface. Greater attachment strength means a greater ability of the
implant to carry load and withstand micro-movements during initial healing
that could interfere with osseointegration. A rough surface also provides
greater attachment area for soft tissue, which improves attachment.
Since the soft tissue is exposed to the oral environment through the
gingival sulcus, the rough surface can contribute to plaque accumulation.
This could cause soft tissue inflammation that is deleterious to the
attachment and healing of the soft tissue. A smooth surface encourages
undesirable bone loss. Since we can not predict exactly how much the
bone will recede, we cannot know what portion of the implant will be
exposed to either the soft or hard tissue. This is why Paragon created
Dual Transition Selective Surface with a smooth 1 mm collar, a 2 mm
medium-rough (SBM) blasted zone (good for hard or soft tissue) and below
this, HA or TPS. We also have implants with SBM surface only that provide
greater bone attachment than a machined or acid-etched surface. SBM
will not be a problem if it becomes exposed to the soft tissue and it
provides more surface area for soft and hard tissue attachment.
Q:
When HA is exposed to soft tissue, the results can be catastrophic failure,
at least on the dental level. When other relatively rough surfaces become
exposed to soft tissue, we really do not know what problems, if any,
we will have...Wouldn’t you agree that the part about rough surfaces
being good for bone adaptation and smooth surfaces being poor is bunk?
A:
I suggest that this doctor read the literature before dismissing as
"bunk" facts that are well documented, such as rougher surfaces increasing
bone attachment (Wennerberg, Buser, Bowers, Block, etc.). As for HA
being disastrous if exposed, I suggest that he read the VA Study results
published in JOMS (1998;56:1302–1311) documenting a 97% success with
1700 HA coated implants with 3-5 year follow-up. All of these Paragon
implants had the HA exposed because they were older designs that only
had a 0.5 mm metal collar, and the average bone loss was over 1.5 mm.
Only 4% of these implants had soft tissue complications compared to
2% for non-coated implants. This doctor further stated: "The manufacturers
think they have all of the answers, but they are just trying to sell
their products...What is the point of manufacturers doing research if
people like this doctor are not influenced by facts?
Q:
You have to separate here what the research is really saying at this
point in time from what the manufacturers are claiming. Isn’t it really
apples and oranges?
A:
I have to agree with this one. Straumann switched from TPS to SLA and
are claiming earlier loading. In fact, the animal studies they cite,
Cochran and Buser, do not show any significant difference in osseointegration
between the two surfaces. Straumann changed to the SLA surface to avoid
the rough TPS becoming exposed and causing soft tissue problems, since
they extended the TPS to the crest of the ridge. Straumann couldn't
admit this was a mistake, so they switched to a blasted/etched surface
without interconnecting pores of TPS and used the excuse of faster healing
to justify the change. 3i just used the acid etching process, which
actually makes the machined surface smoother, and then cites a number
of studies of rough, blasted surfaces to justify their claims of increased
bone attachment. Now they claim earlier loading, which they attribute
to their Osseotite surface without any comparison studies of machined
surfaces side-by-side to support this claim.
Q:
I am slowly getting to use as many different implants as I can to satisfy
my own curiosity as to what is out there. My experience to date is that
they all work and that they work equally well. Can anyone explain why?
A:
While that may be true in the hands of an experienced clinician in good
quality bone, the VA study shows definite differences between acid-etched
and HA-coated implants, with implants of the same design placed side-by-side
in the same patient. SO, THEY DO NOT ALL WORK THE SAME! For example,
in the maxillary edentulous jaw, HA Screw-Vents had a 94%, 3- to 5-year
survival rate compared to only 72% for acid-etched Screw-Vents. HA coated
press-fit implants in the maxillary posterior had a 97% success rate
after 3-5 years, while Brånemark’s machined implants had only
87% in the maxilla, according to an article by Friberg.
DR.
NIZNICK SPEAKS OUT…on The Advantages of Ongoing Product Innovation |
Q:
As far as the development process of the implants, you must still understand
that, while innovation is great, one of the most compelling critiques
of the Core-Vent/Dentsply/ Paragon systems is that they have changed
and changed and changed. Dentists do not want so much change so fast,
even if the innovations are great! For instance, what are you going
to tell those dentists who invested in the now-obsolete COMPLETE IMPLANT
parts and components? The other companies have not changed so many parts
and pieces so rapidly that they obsolete their product line or make
them so cumbersome that they appear confusing to many dentists. And
what was wrong with the healing collar packaging? It had so many parts
it confused many, but it was and is still an excellent way to deliver
either one- or two-stage implants. I guess you will always be able to
justify everything you do.
A:
Thanks for taking the time to direct my focus on the rationale behind
my marketing and product design strategy. I know it may not look like
there is a method to my madness. If it were easy to develop a product
line, make sure it remains current with the changing times and successfully
run an implant business, I guess more dentists and entrepreneurs would
be doing it. Certainly some companies like ITI and Nobel Biocare have
been more successful than I have been by focusing on professional endorsements
and creating a specific culture. 3i has done it through buying opinion
leaders and through misinformation. Neither of these companies is in
a good place as far as their product lines go, with no patent protection,
and now by infringing my patents. 3i can only go so far with its phony
claims on its surface. I think, long-term, the best product will win
out — at least that is where I have to be for my own peace of mind and
professional pride.
I am reading a book entitled,
The Discipline of Market Leaders. Its thesis is that there are three
types of business strategies:
1. Customer intimacy - cultivate
relationships through customer service (e.g. Nobel Biocare)
2. Low prices - (e.g. Lifecore
— started with low prices, but now has a high list price while making
whatever deals it takes to get the sales)
3. Product leadership: "an
offer of the best products, period. Moreover, product leaders don't
build their positions with just one innovation; they continue to innovate
year after year, product cycle after product cycle." (i.e. Paragon)
The book also states that
a "company must first decide where it will stake its claim in the marketplace
and what kind of value it will offer its customers. Then it can identify
core competencies and reengineer the processes that make up the operating
model required to get the job done."
As far as customer intimacy
is concerned, it takes too much money and time to stroke the opinion
leaders. Many are looking for the prestige that comes with being a spokesperson
for a large foreign company, and the money they offer in exchange for
their expressed "opinions" that make up for their products’ shortcomings.
Paragon is focusing on offering
the best customer service through investing in knowledgeable staff,
state-of-the-art on-line ordering, good manuals and organized, simplified
products. At $121-$143 an implant with many additional product advantages,
the Taper-Lock implant allows me to maintain a premium-priced product
line without having to negotiate discounts as other companies do.
I am clearly the market leader
in product innovation because I am not afraid to obsolete my own products,
rather than wait for the competition to do so. Paragon's "core competencies"
include state-of-the-art manufacturing, engineering and an understanding
of how design impacts performance. No other company has a single owner
that is knowledgeable in material sciences, clinical dentistry and has
the total authority to redirect the manufacturing resources as changes
in technology or industry demands dictate.
A perfect example of this
is Paragon's response to the introduction of the double lead, tapered
Mk IV implant from Nobel Biocare. Once they articulated the advantages
of this implant, thereby creating a market for it, I jumped in and did
an end-run around them with triple lead threads on a tapered implant
for insertion into a straight hole. Both of these features where already
covered by Paragon patents and Nobel Biocare has been put on notice
of infringement. Furthermore, I then combined the advantages of both
the Healing Collar Packaging and the Complete Implant by inventing an
Implant Extender, packaged with the AdVent implant. Its large internal
hex will better compete with the ITI implant that requires two neck
lengths and five different heights of cap screws to do what the one
prepackaged AdVent implant can do. The added advantage of the AdVent
is that it will allow Paragon to eliminate more than twice as many parts
as it adds, which will reduce backorder problems, as well as our manufacturing
costs.
As for the Complete System
being obsolete, all the same drills and tools work with the AdVent implant.
A new, stronger hex tool will be made, but the one for the Complete
Implant and Healing Collar Packaging works. The AdVent offers many advantages
that warrant the change. The Complete Implant, while interesting enough
to open some doors and get some interest, did not light the fire I thought
it would. Furthermore, its applications were limited to the non-esthetic
zone and a one-stage protocol. The Healing Collar System was good but
not much better than attaching a healing collar at time of placement.
With the one-piece healing collars, the restorative dentists could detach
them without special tools.
The industry is moving towards
one-stage surgery. The AdVent once again says to the profession that
Paragon continues to take a leadership role in innovation and to that
extent, reaffirms our position as the industry leader in innovation.
To the vast majority of "late
adopters" still stuck on Nobel Biocare or other external hex implants,
hopefully the pricing and features of the Taper-Lock will get them interested.
Our CD-ROM program attempts to educate dentists to be more discerning
and aware that not all systems are equal. The fact that Paragon is the
only company providing this competitive information should say to dentists
that we understand their concerns, we have the answers and we are not
afraid to compare our products to those of the competitors. Our case
registration program gives the surgeon an easy way to provide the information
my staff needs to contact the restorative dentists and guide them through
the abutment selection process. This one-on-one level of customer service,
unprecedented in the industry, eliminates the need for my salespeople
to run around holding the hand of every GP. The Paradigm Shift concept
also eliminates the need of the referring dentist to know what implant
the surgeon used prior to selecting/attaching abutments. If the surgeon
attaches the abutments, there are no new parts or procedures for the
referring dentists to be concerned about with our system. Surgeons no
longer have to spend time hand-holding their restorative dentists—Paragon
will do it for them with the case registration program.
DR.
NIZNICK SPEAKS OUT… on The Complete Implant vs. The AdVent Implant
|
Q:
Please explain the difference between the AdVent and the Complete implants.
I noted that the AdVent requires different drills than the Complete.
Please explain the various drills. Also, the abutment connection platform
for the AdVent appears to be different from the Micro-Vent. Does that
mean that the AdVent is a totally different implant and, consequently,
requires different surgical and prosthetic armamentaria?
A:
I began development of the one-stage implant in 1993. My first effort
was a two-piece, two-stage, Screw-Vent implant with Healing Collar Packaging
rather than Fixture Mount/Transfer Packaging. The 4mmL healing collar
was internally hexed and designed for easy implant insertion. After
osseointegration, the healing collar could be converted into an abutment
by attaching a ball or tapered abutment screw. The healing collar could
also be removed and replaced with a standard preparable abutment for
esthetic, subgingival margins.
In 1997, I introduced the
Complete implant, adding 3.5 mm to the top of the implant and duplicating
the platform of the standard Brånemark abutment. The idea was
that in areas where esthetics did not demand the ability to remove the
collar, why not make it a permanent part of the implant to serve as
an abutment? The shortcoming of this implant was that, in duplicating
the Brånemark abutment platform, I had to use a small fixation
screw. I prefer over-engineering a system, so I was looking for a better
way to accomplish my objectives.
In 1999, I introduced the
AdVent, which combines the best features of the two-piece, two-stage,
implant with Healing Collar Packaging and the Complete implant into
one design. The AdVent has a 3mmL extended collar with a 1mmL tapered
top, allowing the margin of the restoration can be further extended
below the soft tissue. The AdVent platform has a large, 3mmD internal
hex with a lead-in bevel. Although the wide Micro-Vent implant also
has a 3mmD internal hex, its platform is different from the AdVent’s.
This internal hex allows attachment of a much stronger screw than was
possible with the Complete implant. Furthermore, the AdVent’s platform
was designed so that a ZAAG female titanium housing can be screwed in,
providing a low-profile overdenture attachment.
The Complete implant’s cover
screw added another 1.5mm to its 3.5mm attached collar. The AdVent implant,
with its internal hex, uses a low profile cover screw that adds nothing
to its overall height. The AdVent’s low profile cover screw allows the
implant to be countersunk 2mm for a two-stage surgical protocol, if
that is what is desired. The AdVent is also packaged with a 2mmL Implant
Extender that can be placed at the time of stage-one surgery. Once the
implant extender has been attached, it projects up though the tissue
to allow for a one-stage surgical protocol. This works like the one-stage
protocol of Healing Collar Packaging, but with an esthetic, subgingival
margin to the restoration.
Another advantage of the
AdVent implant over the Complete implant is its tapered body. Designed
for insertion into a straight and slightly undersized osteotomy, its
tapered body provides increased stability in soft bone through bone
compression. This unique feature also allows for the elimination of
a narrow 3.3mmD implant, which leaves only the 3.7 and 4.7mmD implants
— both with the same 4.1mmD platform. The AdVent implant also features
triple lead threads for faster insertion. Despite their differences,
however, both the Complete and AdVent implants require the same drills
and insertion tools.
In January 2000, Paragon
will introduce the new Tapered Screw-Vent two-stage implant with triple
lead threads, just like the AdVent implant. It will be available in
3.7mmD, 4.7mmD and 6.0mmD with the same three available platforms as
the current Micro-Vent2 implant. Its tapered body eliminates the need
for a 3.3mmD Tapered Screw-Vent, since the 3.7mmD Tapered Screw-Vent
can be inserted into a socket prepared in a narrow ridge for a 3.3mmD
implant by expanding the bone as it’s diameter widens from 2.7mmD to
3.7mmD during the insertion process.
The new Tapered Screw-Vent,
like the AdVent, will feature Paragon’s patented dual transition surfacing.
The HA-coated implant includes a 2mm blasted (SBM) zone at the crest
of the ridge. The Tapered Screw-Vent will also be available with just
the SBM surface. New step-down drills will be available for inserting
the implant into dense bone, assuring bone engagement by the narrow
apical threads during final seating. When drilling in soft bone, surgical
protocol requires the preparation of an undersized osteotomy. This is
achieved by simply using what has traditionally been the intermediate
drill (2.8mm for 3.7mmD implant; 3.8mm for 4.7mmD implant) as the final
drill. Ideal for use in soft bone and narrow ridges, good bone contact
is achieved throughout the length of the tapered implant, even when
inserted into a socket prepared with a straight drill. This can also
be accomplished with the current straight drills by penetrating to the
score line that corresponds with the implant length with the intermediate
drill, then stopping one score line shorter with the final drill to
create a stepped-down osteotomy.
DR.
NIZNICK SPEAKS OUT… on Implants in the Year 2000 |
Q:
Given the wide variety of implant options from Paragon, what do you
see as Paragon’s main implants in 2000 and beyond.
A:
On rare occasions, new technology will provide a wake-up call to an
entire industry. The need to achieve immediate fixation in soft bone,
the dilemma of inserting an implant into narrow ridges, components that
provide adequate strength, and the solution to repeated screw loosening
have long challenged implant manufacturers. The desire for simplified
surgical protocols, including self-tapping insertion and a one-stage
surgical protocol that provides the esthetics of a two-stage implant,
can be added to these clinical requirements. For implant dentistry to
be a viable alternative to conventional dentistry, implant systems must
provide versatile prosthetic applications with a minimum of components,
complexity and cost. Paragon's AdVent and Tapered Screw-Vent implants
provide viable solutions to these needs, and thus herald a new era in
dental implant technology and innovation.
AdVent and Tapered Screw-Vent
implants share several patented features that transform the quality,
ease and long-term predictability of implant restorations:
- 300% FASTER INSERTION
WITH LESS TORQUE: Three independent, external lead threads spiral
up the AdVent and Tapered Screw-Vent bodies parallel to each other,
as depicted in the tri-colored AdVent implant used in our advertisements.
This patented new triple lead thread pattern enables the implant to
seat three times faster than screw-type implants with the traditional
single-thread pattern. Triple lead threads also reduce torque in dense
bone by 12% (Study: Taper-Lock™ ; implant with triple lead threads
vs. single-thread Branemark clone implant), which lessens surgical
trauma. Paragon holds the industry patent on implants with multiple
lead threads.
- ENHANCED STABILITY &
WARRANTY PROTECTION: AdVent and Tapered Screw-Vent implants feature
a tapered body designed for insertion into a straight socket. This
technique increases mechanical stability at the crest of the ridge,
which improves stability in soft bone and provides a simple technique
for expansion of narrow ridges. This patented insertion protocol assures
initial stability, even in soft bone, allowing Paragon to extend a
guarantee against failure to osseointegrate that includes a replacement
implant.
- MAXIMUM MATERIAL STRENGTH:
Dental implants must be strong enough to resist deformation, metal
fatigue and breakage during long-term functional loading. AdVent and
Tapered Screw-Vent implants are made from surgical grade titanium
alloy, which has been selected to have a tensile strength of 150 ksi.
In comparison, Grade 1 CP Ti and Grade 3 CP Ti implants have minimum
tensile strengths of 35 ksi and 65 ksi, respectively.
- Under 30-degree compressive
force, the AdVent's 4.7mmD implant with an 8mm-long titanium alloy
abutment can withstand 639 lbs. The smallest diameter Tapered Screw-Vent
(3.7mmD) can withstand 378 lbs of compressive force at 30-degrees.
- In torque-to-failure tests,
the AdVent withstood 32.2 in-lbs of force, versus 10.7 in-lbs for
external hex implants made of Grade 3 CP Ti. The smallest diameter
Tapered Screw-Vent (3.7mmD) can withstand 19 in-lbs of force of torque,
far exceeding the amount needed for self-tapping insertion into dense
bone
- INCREASED BONE ATTACHMENT:
The dental literature widely documents the ability to increase bone
attachment by roughening the implant surface. (Ericksson et al.: Clin
Oral Impl Res 1994, Wennerberg et al.: J Biomed Mat Res 1996, Carlsson
et al.: Int J Oral Maxillofac Implants 1988, Buser et al.: J Biomed
Mat Res 1991) However, the procedures generally used to roughen implant
surfaces, such as grit-blasting and coating with TPS or HA, raise
several concerns that have been addressed by Paragon’s SBM™ ; surface
treatment and patented Dual Transition™ ; HA coating.
- TPS-coated surfaces result
in interconnecting pores that can be problematic in soft tissue, if
exposed by crestal bone loss. HA-coated surfaces, when exposed to
the soft tissue crevice, can attract plaque that can cause soft tissue
irritation.
- Grit-blasting with Al2O3
or TiO3 leaves grit imbedded particles on the implant surface.
- HA and TPS coatings, and
grit-blasting with large grit particles of Al2O3
or TiO3 round the threads of the implant and thereby reduce
self-tapping efficiency. Acid etching to remove the grit-blasted particles
further rounds the threads of the implant.
- Paragon's SBM surface
treatment uses a Soluble Blasting Medium
of tricalcium phosphate that produces a medium-rough, non-contaminated
surface, because SBM is soluble and therefore easily removed without
further rounding of the threads.
- Paragon’s HA-coated surface
provides an SBM transition zone approximately 2mm wide near the crest
of the ridge to slow bone loss, and a 3mm SBM apical surface to promote
self-tapping insertion with a coated implant. The HA-coated midsection
increases both the speed (Block MS et al.: J Oral Maxillofac Surg
1987;45:601.), attachment strength (Carr AB et al.: Int J Oral Maxillofac
Implants 1995;10:167–174), percentage of bone contact (Buser D et
al.: J Biomed Mat Res 1991;25:889–902) and clinical success (Morris
HF, Ochi S: J Oral Maxillofac Surg 1998;56:1303–1311) in trabecular
bone.
- APICAL VENTS FOR INCREASED
SURFACE WITH SELF-TAPPING DESIGN: Multiple deep grooves on the apical
ends of implants to accommodate for bone chips generated during self-tapping
insertion reduce surface area. Because the AdVent and Tapered Screw-Vent
are made from medical grade titanium alloy, they have sufficient strength
to allow the addition of a vent at the apical end of the implant,
which varies in size according to the length of the implant. Initially
this vent functions as a reservoir for the deposition of bone chips,
which maintains the cutting efficiency of the implant's self-tapping
threads. The bone chips act as a graft, promoting regeneration of
bone in the vent for additional implant stability.
- 5-YEAR "NO LOOSE SCREWS"
GUARANTEE: AdVent and Tapered Screw-Vent implants feature Paragon's
exclusive, patented internal hex connection and a variety of friction-fit
restorative components that address a full range of restorative options.
When fully assembled, the restorative component forms a "virtual cold
weld" with the implant, which eliminates the leading causes of abutment
screw loosening. In fact, if a cemented restoration must be remade
within five years of attachment because the fixation screw of its
supporting abutment loosens, Paragon Implant Company will replace
the abutment and reimburse reasonable laboratory fees. In North America,
Paragon will also reimburse an additional $100 per abutment.
ADVENT OFFERS ONE- OR
TWO-STAGE SURGERY
Esthetic dental implant restorations
require the ability to provide subgingival margins for a natural-looking
emergence profile. This generally necessitates placement of a two-stage
implant. When esthetics is not a primary concern, a one-stage protocol
eliminates the uncovering surgery and shortens treatment time. Corresponding
surgical trauma is greatly reduced, which can make implant therapy more
acceptable to some patients. AdVent implants include a patented Implant
Extender, which can be used as a transmucosal extension for one-stage
surgery, or as a healing collar for a two-stage procedure. Surgical
specialists can select the protocol of choice at the time of surgery.
The AdVent's Implant Extender packaging thus reduces costs by eliminating
the need to purchase a healing collar or to maintain a large inventory
of both submerged and nonsubmerged implants.
THE TAPERED SCREW-VENT’S
FIXTURE MOUNT/TRANSFER PACKAGING
With three diameters of 3.7mm,
4.7mm and 6mm, the Tapered Screw-Vent offers the versatility needed
to optimize use of available bone. Each diameter option has its own
platform diameter, 3.5mm, 4.5mm and 5.7mm, respectively, which provides
the dimensional options for esthetics and immediate tooth replacement
throughout the entire arch.
All of Paragon's implant
products are made in the U.S.A
|